Emergency Medicine Intraining Exam Review Notes
John Haughey
Revision 2.
2008-2009.

ABEM/ACEP publishes the Model for the Clinical Practice of Emergency Medicine which serves as a content guide. The organization is based on what's useful, common, critical, and testable, which are not always the same. The idea is to make this a memorizable index of those things you should just know.

General_factoids_and_pearls  Meds   Tox Prescriptions   Drug_side_effects

Major Trauma Canadian C spine, NEXUS C spine, c spine fractures, head injury, pelvic fracture, thoracic trauma, neck trauma, open fracture, fracture dislocation, vascular injury, pneumothorax, hemothorax, hemoperitoneum, flail chest, major procedures

Airway  stridor, asthma, COPD, anaphylaxis, the difficult airway

Cardio and Circulation. ekg's, tachycardia, bradycardia, acute MI, CHF, tamponade, aortic dissection, pulmonary embolism, DVT, aortic aneurysm , vasculitis , shock

Blood
peripheral smear, hemophilia, anticoagulants, coagulation profile, transfusion, platelet disorders, anemias, sickle cell, leukemia

Neuro   GCS neurolocalization    uppermotorneuron_vs_lower  cranial_nerves

EYE
pupils  extraocular_muscles  anopias

ENT
epistaxis, epiglottitis, vocal_cord_paralysis,   speech   bulbar_vs_pseudobulbar_palsy

MOUTH

Abdomen  cholecystitis, pancreatitis, appendicitis, diverticulitis, upper gi bleed, lower gi bleed, obstruction, aorto-enteric fistula,

endocrine

Renal hyperkalemia anion_gap hyponatremia hypokalemia hypernatremia hematuria

ortho_and_rheumatology
eponyms, monteggia/galeazzi, bones of the hand, shoulder dislocation, supracondylar, colles, hip, scfe, tibial plateau, ankle, foot.
 
Tox

infectious_disease
immunization schedule,tetanus, sepsis neutropenic patient HIV pneumonia
tuberculosis  influenza meningitis herpes zoster strep pharyngitis otitis media endocarditis
rheumatic vs scarlet fever dysentery-infectious diarrhea
pyelonephritis PID urinary tract infection prostatitis biliary infections cellulitis osteomyelitis
septic joint zoonoses lyme disease
unusual pathogens bioterrorism

minor cases-fast track
paronychia felon chalazion hordeolum foreign body subungual hematoma abscess laceration

environmental
hypothermia, radiation, snakebite,

references
emedicine
NEJM image challenger
UHRAD.com


 
General Factoids and Pearls

PEARLS
- Gosmman, Plantz and Adler- EM Board Review 2000.
all problems exist until proven otherwise
all pills are somewhere
all joints are septic
all children with head injury have hemophilia
all cardiac patients get hypotense after morphine/nitro
all seizure pts dislocate something
all pain that goes away is replaced by something worse
all arhythmias eventually need to be shocked
all patients with the flu have CO, toxin ingestion or a bad infection
all patients who wake up with D50 need admission

FACTOIDS
parkland formula- weight kg times four times percent of burn, 1/2 of LR over first 8 hrs, 1/2 over next, from time of burn.
ett= 16 plus age over 4.
acceptable peds BP: less than 1 <90, >1 it is 80 plus twice the age

Medications (for ER use only, see Prescriptions for Outpatient Scripts)
"If it's worth giving, it's worth giving IV" -Dan Waxman
"You can always give more, you can never take it away"- Amy Wirtner
"that was(not) a genius idea giving that guy ativan and morphine (mortivan)" -shall remain nameless....



Prescriptions

MAJOR TRAUMA
major trauma is a high priority in the emergency department because the golden hour may present an opportunity to resuscitate and diagnose a salvageable traumatic injury.

The trauma team should be activated for the following.
MECHANISM
ejection from auto
death in compartment
pedestrian thrown or run over
speed > 40 mph
deformity >20 inches
intrusion > 12 inches
extrication >20 min
fall >20 ft
rollover
auto vs pedestrian >5 mph impact
motorcycle > 20 mph or separation of rider and bike.

INJURY
flail chest
two or more prox long bone fx
amputation proximal to wrist/ankle
pen trauma to head, neck, torso, extrem prox to elbow and knee
open and depressed skull fx
limb paralysis
pelvic fx
combo trauma plus burn

major burn

SENTINEL SIGNS

this injury or sign is a sentinel sign of another occult injury. 

seatbelt sign- perforating viscus

thoraco-abdominal wound- diaphragmatic injury

c spine fracture- another spinal fracture 

PEA and trauma- tamponade

visual stimulus- pneumopericardium nejm image challenge

AIRWAY/PULMONARY

visual stimulus- patient on BIPAP with anisocoria, cause? ipratropium leaking from mask (from nejm image challenge)

Hemoptysis

("Blood In The Pot: BITP" gives you the common causes: Brochiectasis, Infection, Tumor, Pneumonia)

"A Bit Above Par Golf Club".

A Alkaline (ensure not hematemesis which would be acid)

B Bronchiectasis

I Infection

T Tumor (r/o trauma eg seizure pt comes in coughing up blood- aspirated on his oral laceration)

AboVe : AV malfornations (Osler Weber Rendu/HHT Hereditary Hemorrhagic Telangectasia)

P: Pneumonia, pulmonary embolism

A: Abscess, allergic bronchopulmonary aspergillosis, aspergilloma.

R Renal (SLE, Wegeners, PAN, Goodpastures)

G Goodpastures

C Cardiovascular: mitral stenosis, pulm HTN, LVF

L Look at skin: pulmonary kaposi's sarcoma, vasculitis rash

U Uncommon causes: investigate for nickel carbonyl poisoning, endometriosis, idiopathic pulmonary hemosiderosis, polyarteritis nodosa, pulmonary sarcoid, tuberculosis, drugs

B Behcet.

 

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The following DO NOT cause hemoptysis for exam purposes: constrictive pericarditis, tricsupid stenosis, asbestosis, fibrosing alveolitis (uncommon), asthma, chronic bronchitis (although acute bronchitis may), asthma.

Investigation.

FBC looking for anemia, white cell count.

Chest x ray.

CT chest

ANCA, rheumatoid,

Culture and sensitivity sputum, acid fast bacillus

ABG

ECG- pulm htn, LVF.

TB: ppd. positive result. 5 mm for HIV, 15 mm for general public, ignore BCG after 10 years unless strongly positive with history of exposure less than ten years.

 

 

causes of hemoptysis- for 4 patients, one neoplastic, one nontubercular, one miscellaneous, etc, look in tintinallis

CARDIO and Circulation

Shock is defined as inadequate perfusion to meet the needs of tissue metabolism.

Shock can be compensated or decompensated.

Decompensated shock is defined as shock plus systolic hypotension, or
IF BP is unmeasurable, defined as absent distal pulses, prolonged capillary refill, cool extremities, tachycardia, altered mental status (decreased level of consciousness/responsiveness)

Maximum allowable heart rates.

newborn-to 3 months- 85-205.
3 months to 2 yrs- 100-190.
2 yrs to 10 yrs 60-140.
>10 yrs 60-100

MINIMUM acceptable blood pressures
below 12 hours of life and less than 1 kg of weight. 39 systolic.
12 hours of life, 3 kg neonate- 50 systolic
neonate- 96 hours of life- 60 systolic.
Infant- 1 month to 1 year- 70 systolic.
child from age 1-10 =[70 + (2x age in years)]
child age 10 plus= 90 systolic

Criteria for dehydration in children.
minimal (<5%)dry MM, plus or minus tachycardia plus or minus decreased UO.
there will be NO depressed fontanelle, sunken eyeballs, abnormal turgor, cap refill prolonged, weak pulses, hypotension, hyperpnea, altered mental status, or acidosis.

moderate (5-10)positive for dry mm, tachy, depressed fontanelle, sunken eyeballs, decreased uo, PLUS or MINUS turgor, altered, acidosis.
severe (>10) requires weak peripheral pulses, hypotensions, hyperpnea, altered mental status, acidosis, high urine sp grav.

class 1,2,3,4 hemorrhage
class 1-
up to 750 mL blood loss, pulse less than 100, normal BP, normal or increased pulse pressure, rr 14-20, UO >30 mL/hr (0.5 ml/kg), slightly anxious mental status, replace with 3:1 crystalloid:blood. (3 liters crystalloid for every unit of blood)

class 2-
up to 1500 mL blood loss, pulse >100, normal BP, decreased PP, RR 20-30,UO 20-30,mildly anxious. replace with 3:1 cystalloid:blood.

class 3-
up to 2000 mL blood, pulse >120, decreased BP, decreased PP, RR 30-40, UO 5-15, anxious/confused, replace with crystalloid and blood.

class 4
>2000 mL blood, pulse >140, decreased BP and PP, RR >35, negligible UO, confused/lethargic, replace crystalloid and blood.

Metabolism generates ATP which keeps biological membranes intact and functioning (brain and cardiac).

ATP can be generated through anaerobic and aerobic metabolism.

Although seemingly logical, ATP cannot be injected directly into a tissue to improve performance, for a variety of reasons. British Journal of Anaesthesia 94 (5): 556–62 (2005)
http://bja.oxfordjournals.org/cgi/reprint/94/5/556

Anaerobic glycolysis does not require oxygen or mitochondria, it occurs in the cytoplasm. It generates lactate and acid as a byproduct, leading to lactic acidemia.

Aerobic metabolism requires oxygen and the electron transport chain of the mitochondria, it takes longer than anaerobic glycolysis.

For perfusion to occur, cardiac output must be maintained, which requires heart rate and stroke volume. CO=HRxSV

AORTA.

the aorta if torturous can be a sign of osteoporosis. see nejm visual stimulus. http://content.nejm.org/cgi/content/full/358/22/2388 

VASCULITIS

visual stimulus- renal angiogram- polyarteritis nodosa-microaneurysms. nejm-angiogram

The apex beat, also known as the point of maximal impulse (PMI) is defined as the most lateral and inferior point at which the palpating fingers are raised during each systole.

The normal location is in the 5th ICS one centimeter medial to the MCL in adults. In children it is located in the 4th ICS and more laterally.

Normal timing is systolic. Normal area is less than a US quarter. Should be the size of a finger.

The actual mechanical cause of the apex beat is a little fuzzy in most people's minds. If you think of the heart as a cannon, and blood as the cannon ball, the apex beat is the movement of the heart backwards against the chest wall as the blood is expelled (recoil) according to Newton's Third Law of Motion. Some cardiologists say the heart doesn't actually move in the thorax. The apex beat doesn't actually mean that the apex of the heart is located at the palpable site. Supposedly the heart assumes a spherical shape due to ventricular contraction during systole, and thus the actual apex is twisting away from the chest wall, however the area ABOVE the apex moves closer to the chest wall and is palpable.

---

Eliciting the sign.

There are two ways of going about this. The traditional way is to search from the axilla, searching from the most lateral and inferior position until the beat is located. Then, try to determine the position once it is detected. This will prevent the temptation to simply look for where it is supposed to be and miss what could be a diffusely enlarged or double apex beat. Better to look for it from the axilla than to simply assume that if it is where it is supposed to be that that is only where it is.

Using your right hand, first locate the 2nd ICS by locating the manubrium sterni and counting down. Then move in the 5th ICS with your middle finger in the 5th ICS groove, with your index finger in the 4th and your ring finger in the 6th. Feel whether the PMI is in the 5th ICS medial to the MCL. If it is not, then it is displaced, however if it is present here, this does not mean it is not displaced... it could be diffuse or a double impulse, and simply feeling where it is SUPPOSED to be and finding it, does not confirm it is not displaced. Feel laterally and inferiorly. Once you find it, note its position, then use your left hand to palpate the carotid pulses. Use your thumb to press over the right carotid artery to time the pulse. The carotid pulse is located medial to the SCM in the angle between the mandible and the SCM. It may be convenient to remember the character of the carotid pulse at this time as some patients may not appreciate multiple palpations of their neck. The reason that you are doing this is to time the beats. Some examiners may prefer to use the brachial or radial pulses to do this.

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Differentials.

An impalpable apex beat suggests either the heart is not beating(death/cardiac arrest), is beating poorly (shock), is located on the right side of the chest (situs inversus, Kartagener syndrome), or there is some substance between the heart and the chest wall such as air (hyperinflation/COPD), fluid (tamponade or pericardial effusion), or fat (obesity).

A displaced apex must be considered wrt tracheal position. If the tracheal is not midline, then the cause is probably mediastinal shift. If the trachea is midline, then the causes include enlargement(with inferior and lateral displacement),thoracic deformity(pectus excavatum,scoliosis, straight back) pleural or pulmonary disease.

"Displacement of the apex beat lateral to the midclavicular line or more than 10 cm lateral to the midsternal line is a sensitive but not specific indicator of left ventricular enlargement. However, when the patient is in the left lateral decubitus position, a palpable apical impulse that has a diameter of more than 3 cm is an accurate sign of left ventricular enlargement." (Braunwald)

The character is important. The character is best assessed in the left lateral position (the location is not best assessed in this position). Remember that the key thing to visualize is the heart expelling blood and recoiling.

Pressure loaded. Heave. "high amplitude", "sustained", plus or minus "displaced", plus or minus "increased area" This means the heart is hyperdynamic or systolic overloaded. The beat is forceful and sustained. This occurs where the recoil of the heart is longer due to overcoming resistance of aortic stenosis or hypertension. If the heart is also hypertrophied (findings more common with concentric hypertrophy) the location will be displaced laterally and down into the 6th and 7th ICS, and the beat will be more diffuse over an approximate 3 cm area. This is known as a left ventricular heave or lift.

Hyperdynamic=thrusting. If beat is increased in force but not sustained in time, this may be due to a thin person, a person with mild LV enlargement, aortic or mitral regurgitation, a person with a normal LV size but who is excited or anxious or has a large stroke volume.

Dyskinetic. "increased area". Increased area is defined as larger than a US quarter. This beat is felt over a larger area (diffuse), and may be due to impaired LV function (eg due to anterior MI). The recoil is spread out because the heart is not beating in a coordinated fashion.

Double impulse. Timing (not position):: one presystolic, one in systole. "double/triple impulse", plus or minus "sustained", plus or minus "increased amplitude" Two beats are felt with each systole, this suggests hypertrophic cardiomyopathy. The impulse may be felt two or even three times in the same position and is said to be caused by two events. First, the presystolic expansion of the ventricle during atrial systole (late ventricular filling/ LV diastole), and secondly the recoil of the heart against the chest wall with LV systole. You would expect the second beat to be sustained if obstruction was present. This is essentially the same as a palpable S4.

Retraction. If the chest wall is observed to retract during systole this is a sign of constrictive pericarditis (retraction of ribs in left axilla=Broadbent sign), note this is not equivalent to Harrison's sulcus which is a linear depression of the lower ribs above the costal margins at the site of the diaphragm attachment(suggests rickets, severe asthma in childhood).

Tapping. There are a lot of explanations for this. Timed at beginning of systole. This, in contrast to the above, is either (depending who you read) 1. due to a palpable first heart sound M1T1 caused by closure of either the mitral or tricuspid valves when stenotic and is not due to recoil of the heart after blood expulsion. 2. Some cardiologists say the tapping beat of mitral stenosis is because the left atrium is massively dilated, this compresses the heart against the chest wall and makes the apex beat more prominent. 3. Caused by increased pliability of the anterior mitral valve leaflet.

Diastolic overload. "diastolic timing". can occur with mitral regurg, poor LV fxn, or with LV volume increase. It means that diastolic filling results in a palpable impulse, which is equivalent to a palpable S3. This is best heard in full exhalation in the left lateral position.

Ectopic impulse. Note that this is a cause of a double impulse in terms of position but may also be in terms of timing. Is a sustained systolic bulge several centimeters superior to the apex associated with an LV aneurysm. This can also produce a diffusion of the apex impulse over a larger area.

A note on the words hyperdynamic, heaving, thrusting, lifting...Heave means sustained and vigorous (high amplitude). Thrusting=hyperdynamic which means vigorous (high amplitude)but not sustained. It is probably better just to describe the type of impulse in terms of its duration, it's amplitude, it's area, it's location, and the timing.

For more information see the Clinical Exam Site., or See Talley and O'Connor 4th ed. pgs 49-50, 72, 112-113.

Zipes: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., Copyright © 2005 Saunders, An Imprint of Elsevier Page 87 accessed online at mdconsult.com

Kumar and Clark page 712 5th ed.

JVP

stands for jugular venous pressure, or jugular venous pulse.

The classical memorized pat phrase about the JVP is: the JVP is impalpable, fills from above, located between SCM heads, alters with changes in respiration and position, is a complex waveform with a double pulse for every arterial pulse, and can be elevated with abdominal pressure (hepatojugular reflux).

First, expose the neck, obtain adequate light source, have the patient turn the neck slightly to the left, locate the venous column, between the heads of SCM, move the patient from lying to sitting straight up to see the meniscus and differentiate it from carotid pulsation. Have the patient breathe in and out to see it move. Make sure it is the JVP by applying pressure to the abdomen and observing an increase in the level of the JVP (hepatojugular reflux). Then, have the patient lie back to 45 degrees.

With the patient lying between 30 and 60 degrees to the horizontal, measure the vertical distance from the manubriosternal angle to the top of the venous column.

Textbooks vary, however, the normal JVP is 3 cm above the manubrium sternal angle, corresponding to a right atrial pressure of 8 cm of water at a point halfway between the anterior and posterior chest.

Clinically, a raised JVP indicates heart failure, volume overload, renal disease with retention of salt and water, constrictive pericarditis/tamponade, SVC obstruction.

A low JVP cannot be measured clinically. Causes include hemorrhage, shock, and hypovolemia.

The characteristics of the pressure wave are considered here.

The waveform consists of a, x descent, c, v, and y descent.

a is for atria. a wave is atrial contraction, the last phase of ventricular diastole, it precedes ventricular systole.

c is for closure. c wave is closure of the tricuspid valve

x is for relaXXXXX of the atria. x descent is the fall in atrial pressure at the onset of ventricular systole

V is for valve and ventricular systole. v wave is atrial filling against a closed tricsupid valve in ventricular systole

y is for diYYYYastolic. y descent is the opening of the tricuspid and the first phase of ventricular diastolic filling preceding diastasis (the middle of ventricular diastole).

On gross inspection, the timing is as follows. The flicker you see before the transmitted pulse is an "a" wave. The flicker you see after the transmitted pulse is a "v" wave.

Feel the pulse. Look at the JVP. If the flicker BEFORE the pulse is big, these are A waves, and represent the atria contracting against a closed tricuspid valve in electromechanical dissociation, or they can represent pulmonary hypertension because the atrial contraction cannot force the last bit of blood into the right ventricle.

If the flicker AFTER or WITH the palpated pulse is big, these are V waves, which represent tricuspid regurgitation in ventricular systole.

tricuspid regurg: big v waves (after/with the palpated pulse), high pressure, separate c and v waves, big x and y descents. if accompanied by RV Failure, may be associated with big A waves.

pulmonary htn: big a waves

RV failure: CV waves (after or with the palpated pulse).

Electromechanical dissociation: Giant cannon A waves before pulse

The JVP is one of those traditional things that you have to know about. HOWEVER, if you find it is raised, it is quite good as a fairly specific sign, for example in the diagnosis of CHF .

An objective assessment of central venous pressure by a central line isn't a very good measure of volume status but people still do it.

The only really important thing you need to bother about is obstructive shock in the Weil-Shubin classification of shock, because there are basically three things that cause a deranged jvp.

In obstructive shock, the heart cannot get enough preload. This can be due to a massive pulmonary embolism blocking return from the right side of the circulation, a tamponade obstructing entry into the heart, or pericarditis.

In all of these situations, you must act quickly. For example, you should not wait for a CT scan or D dimers to exclude PE. You must act within minutes to empirically heparinise the patient. Likewise, with tamponade, you cannot wait for an echo, you must act within minutes to decompress the tamponade. It is in these emergency situations that the JVP is useful. HOWEVER, when was the last time you saw a patient with one of these conditions in extremis lying at 45 degrees? Yeah. Never. Most patients who are seriously ill are lying flat. SO, if you are going to assess the JVP in a patient with suspected PE or tamponade, you have to be able to sit them up. Not possible in a trauma patient on a backboard.

HEMATOLOGY

visual stimulus- peripheral smear.
malaria vs babesiosis. in babesiosis you can see intracellular organism ring forms in the rbc'swith tetrads in a maltese cross formation.
note that howell jolly bodies are dna in erythrocytes in asplenic patients.
babesiosis at NEJM.

NEUROLOGIC

associations:
AMS plus ________equals:
alcohol- subdural
young healthy-overdose
jaundice- hepatic failure
petechial hemorrhage- ITP/DIC/leukemia/meningitis/renal/hepatic failure
incontinence- seizure/cva
barrel chest-respiratory failure
pulmonary edema and otherwise well- heroin, cocaine, salicylate
tachypnea- resp failure/acidosis/high anion gap acidoses

Upper Motor Neuron vs. Lower Motor Neuron

UPPER	LOWER
weakness without wasting. LL: flexors, abductor. UL abductors/extensors	weakness with wasting. Distal>proximal. Flexor=extensor.
spasticity	hypotonia
increased reflexes	hyopreflexia
upgoing toe (extensor plantar), positive Babinski	normal plantar (down)
	fasciculation

Note: an important thing to look for is the combination of hypertonia with fasciculations. This mix of upper and lower motor neuron signs is suggestive of motor neuron disease aka ALS, or in front of the patient: "anterior horn cell disorder".

radicular pain-bilateral feet paresthesias-ascending sensory loss/weakness- ddx- transverse myelitis vs spinal abscess

weakness/atrophy/fasciculations followed by spastic paralysis- ALS- motor neuron dz (mixed signs) ddx- spinal cord disorders.

paraplegia:both legs

diplegia :legs more than arms.

hemiplegia: half of one side.

tetraplegia: all four limbs

spastic paraparesis: multiple sclerosis

carotid bruit

A carotid bruit is a noise heard over the carotid arteries. It does not always signify carotid stenosis, and must be distinguished from other noises in the neck.

Other noises in the neck confused with carotid stenosis include: venous hum, transmitted murmur, carotid aneurysm, goiter.

Carotid aneurysm is associated with htn, dm, smoking. It is a pulsatile, usually unilateral swelling, along course of carotids, may be at the base of neck, and may be firm. It is associated with horner's syndrome, as well as other pulse abnormalities. Although rare, most likely cause is atherosclerosis, post trauma, post endarterectomy, and most important complication is rupture. Diagnostic workup includes digital subtraction angiography, plus or minus MRA. Note that an aneurysm may be hidden behind an embolism (much like an enigma wrapped in a riddle), thus on angiography the vessel may appear normal. American Journal of Neuroradiology 21:546-548 (3 2000). Although it is usually unilateral, the other side of the neck should be investigated in case it is bilateral.

Internal Carotid artery stenosis (ICAS)can be present without a bruit, and this is the case __ percent of the time. In one series, 32% of patients with normal arteries had a bruit, whereas 43% of patients with severe disease did not have one. Postgrad Med J. 1994 Jun;70(824):433-5. While other studies also confirm that finding a bruit is useful, it's absence does not mean it is not there. Angiology. 1988 Nov;39(11):967-72.

The most common presenting complaint of symptomatic!!! carotid stenosis is amaurosis fugax 21% of the time (75 patients) in a series of 366 patients being evaluated for CEA with angiography. 10 of 41 patients with documented eye findings and greater than 50% stenosis had amaurosis fugax. Vasc Endovascular Surg. 2002 Nov-Dec;36(6):415-24. Ophthalmologic findings as predictors of carotid artery disease. Lawrence PF, Oderich GS.

Amaurosis fugax is a retinal artery TIA which is a painless unilateral loss of vision lasting minutes.

Approximately ______ percent of carotid stenosis is asymptomatic.

Approximately 4-8% of the population aged 50-79 has a carotid stenosis greater than 50% ...Mayo Clin Proc. 2004;79(7):937-944

For asymptomatic carotid artery stenosis, in the European Carotid Surgery Trial (ECST), the 3-year risk of ipsilateral stroke was 1.8%, 2.1%, and 5.7%, corresponding to degrees of stenosis of 0% to 29%, 30% to 69%, and 70% to 99% ...Randomised trial of endarterectomy for recently symptomatic carotid stenosis: final results of the MRC European Carotid Surgery Trial (ECST). Lancet. 1998;351:1379-1387.

In the North American Symptomatic Carotid Endarterectomy Trial (NASCET), the 5-year risks of ipsilateral stroke were 7.8%, 12.6%, 14.8%, and 18.5%, corresponding to initially asymptomatic stenoses of less than 50%, 50% to 59%, 60% to 74%, and 75% to 94%.3. ...Barnett HJ, Taylor DW, Eliasziw M, et al, North American Symptomatic Carotid Endarterectomy Trial Collaborators. Benefit of carotid endarterectomy in patients with symptomatic moderate or severe stenosis. N Engl J Med. 1998;339:1415-1425.

Each year, the risk of stroke with asymptomatic stenosis is between 1 and 3%, depending on the degree of stenosis.

First-ever stroke subtypes in patients with previously asymptomatic ICAS are commonly embolic (90%) and are seldom due to hemodynamic or perfusion failure....North American Symptomatic Carotid Endarterectomy Trial Collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325:445-453.

TIA occurs in 70% to 89% of patients with previously asymptomatic ICAS, which allows conservative management of asx carotid stenosis until TIA occurs, then aggressive management of TIA.

In asymptomatic ICAS, the risk of TIA is greater than the risk in patients without stenosis.

In asymptomatic ICAS, surgery is effective in reducing risk of stroke by approximately 30%, however the absolute risk reduction is only about 1% per year.

AAFP review of subject..Am Fam Physician 2000;61:400-6

See Decisionmaking for carotid stenosis.

Causes of a Peripheral Neuropathy  (see pg 419 Talley/O'Connor 4th ed)

A. Alcohol, amyloidosis

B. B vitamin. Excess of B6, deficiency B12, B1 deficiency with alcohol.

C. cancer, connective tissue(PAN/SLE), paraneoplastic

D. Diabetes, drugs (isoniazid, vincristine, amiodarone, cisplatin, phenytoin, nitrofurantoin,heavy metals)

E. SLE.

F. Familial

G Guillain Barre. G for genetic.

H HIV

I Idiopathic

J juveniles: hereditary motor and sensory

K Kidney

L Lymphoma/leukemia

Causes of Predominantly Motor Neuropathy

1. Guillain Barre, chronic inflammatory polyradiculoneuropathy

2. hereditary motor and sensory neuropathy

3. diabetes mellitus

4. acute intermittent porphyria, lead poisoning, diphtheria, multifocal conduction block neuropathy

Causes of painful peripheral neuropathy

1. Diabetes(painless?)

2. alcohol

3. B1 B12 deficiency

4. carcinoma

5. porphyria

6. arsenic or thallium poisoning.

GCS- proceed from eyes on top, to mouth below, to arms and legs below, in order, 4,5,6 as one works down the body. 3 is the lowest score.

to remember movement- extensor posturing has the hands by the sides- which is fewer points (2)than flexor posturing which has the hands flexed (3)- higher hands-higher points.

typical trauma patient-  with eyes open to pain (2/4), a moaning patient (2/5), pulls away when nail pinched- (4/6)= 8= intubation

typical alcohol intoxicated patient- eyes open to speech (3/4), confused (4/5), and localizes (5/6)(pushes examiner's hand away from face when pressing on orbits by crossing midline). = 12.
Best eye response (E)

There are 4 grades starting with the most severe:

1. No eye opening
2. Eye opening in response to pain. (Patient responds to pressure on the patient’s fingernail bed; if this does not elicit a response, supraorbital and sternal pressure or rub may be used.)
3. Eye opening to speech. (Not to be confused with an awaking of a sleeping person; such patients receive a score of 4, not 3.)
4. Eyes opening spontaneously

Best verbal response (V)

There are 5 grades starting with the most severe:

1. No verbal response
2. Incomprehensible sounds. (Moaning but no words.)
3. Inappropriate words. (Random or exclamatory articulated speech, but no conversational exchange)
4. Confused. (The patient responds to questions coherently but there is some disorientation and confusion.)
5. Oriented. (Patient responds coherently and appropriately to questions such as the patient’s name and age, where they are and why, the year, month, etc.)

Best motor response (M)

There are 6 grades starting with the most severe:

1. No motor response
2. Extension to pain (adduction of arm, internal rotation of shoulder, pronation of forearm, extension of wrist, decerebrate response)
3. Abnormal flexion to pain (adduction of arm, internal rotation of shoulder, pronation of forearm, flexion of wrist, decorticate response)
4. Flexion/Withdrawal to pain (flexion of elbow, supination of forearm, flexion of wrist when supra-orbital pressure applied ; pulls part of body away when nailbed pinched)
5. Localizes to pain. (Purposeful movements towards painful stimuli; e.g., hand crosses mid-line and gets above clavicle when supra-orbital pressure applied.)
6. Obeys commands. (The patient does simple things as asked.)

DERMATOMES

Key dermatomes points for testing.

C3: Clavicle.

C4: Over shoulder tip.

C5: Lateral arm above elbow.

C6: Lateral forearm down to thumb. Both palmar and dorsal thumb.

C7: Tip of index finger, palmar surface.

C8: Dorsal surface of pinkie.

T1: Medial anterior forearm in cubital fossa.

T2: Medial armpit.

Ulnar nerve: C8 T1.

Lower limb.

L1: groin, hands in pockets. Inguinal Ligament IL LI.

L2: groin, at sapheno femoral junction, 4 cm below and lateral to pubic tubercle

L3: Medial thigh.

L4: Medial lower leg.

L5: Cleft between first digit and second. Lateral lower leg.

S1: Lateral malleolus. Sole.

S2: Medial back of leg, medial behind knee.

S3,4,5: Saddle.

NEURO-LOCALIZATION

Anterior Cerebral Artery: Generally supplies the legs due to the mapping of the motor cortex. Upper motor neuron signs in legs more than arms. cortical sensory loss in legs, urinary incontinence.

 

Middle Cerebral Artery: Supplies the face, upper limbs, trunk, and proximal lower extremities. gaze preference. homonymous hemianopia.

If the middle third of the hemisphere main branch is infarcted the signs include UMN face, arm>leg, homonymous hemianopia, aphasia or non dominant hemisphere signs, cortical sensory loss.

Middle cerebral artery: internal capsule: UMN faceUMN arm>leg

Post cerebral artery: contralateral homonymous hemianopia, ipsilateral cn3, hemiparesis, memory loss,

vertebrobasilar- ipsilateral CN, cerebellar, contraleteral hemiplegia, hemisensory loss,  N/V/nystagmus/vertigo/tinnitus/hearing loss.

basilar artery- quadriplegia, upward gaze/locked in.

lacunar- internal capsule-  midpons=clumsy hand/dysartria, pons/internal capsule=ataxia/leg paresis/motor hemiplegia, thalamus- sensory.

Funiculus gracilis: sensory tract, fine touch, proprioception, from legs, is medial in the spinal cord below T6.

Funiculus cuneatus: sensory tract, fine touch, proprioception, from the upper body: is lateral in the spinal cord above T6

Posterior columns: sensory tracts: legs located medially, arms lateral in the spinal cord. Mapping in the medulla is the same. In the pons, midbrain and the thalamus, the arms become medial and the legs lateral.

Pyramidal tract: motor tract: lateral pyramidal controls distal and fine movements, medial controls proximal and axial movements, postural tone.

Spinothalamic tract: sensory tract: lower regions are lateral, upper regions are medial in spinal cord, explains "sacral sparing" with medial lesion to spinal cord.

Speech

DDX: speech/changes in voice : (see dysphonic vs dysphasic vs dysarthric below)

DYSPHONIC

1.Hypothyroid : changes in voice. husky, hoarse, low pitched, croaking, catarrhal, variegated dysarthria.

2. Hoarseness less than three weeks: acute laryngitis, voice abuse, status post neck surgery (thyroidectomy), status post intubation/bronchoscopy, trauma, cough/strain, tobacco, anaphylaxis.

2. Hoarseness: greater than three weeks: consider laryngitis, reflux, smoking, voice abuse, carcinoma of lung w/ left recurrent laryngeal nerve palsy, laryngeal carcinoma, mediastinal compression (retrosternal goiter, lymphoma, aortic aneurysm), vocal cord nodule/polyp, hypothyroid, rheumatoid arthritis,

3. Myasthenia: poor volume and fatigue

4. Spasmodic dysphonia: strangled strained voice, hyperadduction of cords

5. non-organic causes: misuse/abuse, muskuloskeletal tension, ventricular dysphonia, conversion disorder, mutational falsetto (a drop in pitch with coughing or laughter rules out hypogonadism, presence of mature larynx).

DYSPHASIC/APHASIC

1. Stroke.

2. Wernickes: receptive aphasia

3. Brocas: expressive aphasia

Gerstmanns(not speech per se but language): alexia, agraphia, acalculia

DYSARTHRIC

1. Stroke.

2. Cerebellar pathology: dysarthria

3. Motor neuron dz: progressive bulbar palsy. nasal speech, fasciculating tongue, palatal paralysis.:

4. Multiple Sclerosis: slurred speech.

5. Parkinsons: slurred low volume monotonous speech : spastic dysarthria , swallowing difficulty, slow tongue, dysarthria

6. Huntingtons: spastic dysarthria: slurred monotonous speech

other dysarthric:

Bulbar palsy : flaccid dysarthria

Pseudo bulbar palsy : spastic dsyarthria

Myotonic Dystrophy: slurred speech. /spastic dysarthria.

Friedrichs Ataxia

Clumsy Hands syndrome: pons: dysarthric

DEFORMITY RELATED.

MACROGLOSSIA.

Cleft palate

Eliciting Changes in Speech.

HISTORY

First introduce yourself, obtain consent to examine the patient.

Ask the patient his/her name, where they live/are from, and why they are in hospital today.

At this stage a deficit may be evident in understanding which may suggest a receptive aphasia.

Ask patient to talk freely- to describe their job, lifestyle, the room, clothes, etc as a means of assessing propositional speech. This can reveal difficulties in expression, as well as articulation.

Even better, ask the patient to describe what it is they had for lunch in detail.

Then ask about difficulty swallowing, if there is any pain, or any nasal reurgitation.

Ask the patient if they have had any symptoms suggestive of hypothyroidism: changes in voice, cold intolerance, fatigue, coarse hair, weight gain.

Ask the patient if they have had any neurological symptoms: double vision, blacking out, falls, tingling, tremor, clumsiness, weakness, difficulty walking, dressing, going to toilet, balancing check book, using transport.

EXAMINATION

Inspection: Look for Parkinsons facies, pes cavus in freidrichs ataxia, nystagmus or intention tremor, signs of stroke such as hemiplegia and or facial droop.

Tell the patient you are going to ask them a few questions and ask them to do a few things and do not be frustrated if you cannot answer them.

Assess comprehension/receptive aphasia.

-Without gesturing, tell patient to stick out tongue, shut eyes, touch nose.

-Show the patient a card which says “close your eyes”, and ask the patient to do what it says.

-Give the patient a three stage command. Place a piece of paper in front of them, tell the patient to please “pick up the paper with your right hand, fold it in half, and give it to me”

Assess naming and expression.

Ask patient to name a pencil and a watch.

If the patient cannot name them, hold up some keys and ask: is this a spoon? Is it a pen? is it keys? to which they may be able to answer.

Ask the patient to repeat the phrases “west register street”, british constitution, hippopotamus, constantinople is the capital of turkey. artillery.

If naming is intact, assess sentence forming ability and ask them to describe as many objects in the room as they can. Ask them to tell you where they live and how they get there.

If the patient cannot express themselves, consider whether this is due to a focal lesion or an orofacial dyspraxia.

Tell the patient to perform movements of the face, without gesturing to them, such as: “show me your teeth”, and “move your tongue from side to side”.

Then, ask the patient to perform the movements while you gesture: to assess whether the problem is purely of a motor nature (ideomotor) or whether it is ideational (eg difficulty with the complexity of the command).

Assess articulation:

lips: me me me me

tongue: la la la la

Pharynx: Kuh, gut,

Palatal Paralysis: say ahhhh, speech worsens when head bent forwards.

"betty bought a bit of butter"

loss of tongue: beey bah a bi o bu-er

loss of lips: tty tout a tit of tuter

Assess writing.

Ask the patient to write a short sentence.

Assess hemispheric neglect (visual attention)

Ask the patient to copy a drawing of a clock. 1 point.

Assess attention and calculation.

Ask the patient to count backwards by 7’s from 100.

If there are deficits, consider performing either a mini-mental state exam or an abbreviated mental state exam.

MMSE: orientation, registration, recall, attention and calculation, parietal skills.

"ORARP"

Orientation (10): date, day, day, month, year, holiday, town, streets, address, head of state, popular person

Registration (3): ball flag tree, repeat (score first trial, repeat until achieve repetition up to 6x)

Attention/Calculation(5): Serial sevens or world backwards

Recall (3): recall three objects

Parietal (9): naming, repetition, reading, writing, 3 stage command, copying.

MMSE total:: /30. Concern if value less than 24.

Assess the cranial nerves involved in vision, speech and hearing.

2nd cranial nerve: assess visual fields in each eye by confrontation, assess acuity, pupillary reflexes and funduscopy.

3,4,6: quickly assess the cardinal positions of gaze.

5th cranial nerve: assess sensation on the face.

7th cranial nerve: tell the patient to show you their teeth, puff their cheeks, raise their eyebrow. Palpate the muscles of the face as they do so bilaterally.

8th cranial nerve: whisper the numbers 68 and 100 in each ear while distracting the other ear with rubbing of fingers. With a 512 hz tuning fork, perform weber and rinne tests.

9, 10: gag reflex. assess palatal elevation. Say aaaahhhhhh. Elevation of the uvula. Deviates away from side of lesion. Remember: Say Ahhh Away..

12th: hypoglossal: ask the patient to stick out their tongue. Deviates to side of lesion.

Remember: Twelfth is Towards and its the Tongue.

Summarize.

This patient, Mr Blog, on general inspection shows no facies of hemiplegia or neurodegenerative processes. No signs of dysphonic, dysarthric or dysphasic speech are evident. Articulation, repetition, comprehension, naming, propositional speech, visual attention, writing, reading, attention, and calculation are intact. Cranial nerves 2-12 are intact. I would like to formally assess the patients orientation, registration, and recall, and refer for formal audiometry.

Dysphonia	Dysarthria	Dysphasia, Expressive	Dysphasia, Receptive
Inability to produce a voice of normal volume/character.	Disorder of articulation	Disorder of expression, speech repetition, naming, reading aloud	Disorder of comprehension
Abnormal volume, whispering, Husky, inability to maintain a note such as “eeeeee” in myasthenia gravis., hoarseness	Slurring, difficult pronunciation, worse with complicated phrases such as “west register street”.	Difficulty naming with intact ability to recognize objects (pen, tie, watch) correctly when presented with options(is it a pen? Watch? Tie? Lapel?)	Difficulty understanding commands. (Open your mouth,, touch your nose) Speech is fluent but meaningless.
Damage to nerves involved in voice production, laryngeal nerves, laryngeal/vocal cord pathology Also, myasthenia gravis	Cerebellar lesions , basal pontine clumsy hands syndrome, muscular lesions, neuromuscular junction, mechanical defects, cleft palate, impaired hearing	Broca’s aphasia.	Wernicke;s aphasia.

neurolocalization

Wernicke’s Area: Parieto-temporal cortex. Superior temporal gyrus, area 22. Patients with Wernicke's aphasia cannot comprehend spoken commands but may be able to understand written language because written language is coded in a separate area of association cortex in which information from the occipital cortex is associated with meaning (angular gyrus, area 39, Gerstmann syndrome). Mnemonic: Wordy aphasia… “Wernicke’s speech is Wordy but Without meaning… “

Broca’s area: left posterior frontal lobe, third left frontal gyrus, areas 44.45. It is a motor association cortex for face, tongue, lips and palate. The left posterior frontal lobe is near the motor cortex (precentral gyrus) and is a cortical area concerned with the mechanical elements of speaking known as Broca's area. Patients with lesions to this area can understand words, but may have difficulty vocalizing. A patient with Broca's aphasia may not be able to write either because the middle cerebral artery affects the motor cortex controlling the face and upper limbs (eg hands).

Mnemonic: The speech is broken, Broca’s Broken aphasia.

Arcuate fasciculus. This is a tract in the parietal cortex which connects Broca's area with Wernicke's area. Lesions to this tract result in the inability to select the correct words to convey a thought while retaining complete understanding and ability to speak. Thus circumlocution is present.

Angular gyrus Area 39. Lesion of the angular gyrus results in Gerstmann syndrome, loss of ability to read (alexia),write(agraphia), calculate(acalculia). The angular gyrus is an association cortex where visual and somatosensory stimuli can be encoded into auditory information.. This can be restricted remarkably while retaining the ability to converse normally, even to the extent that individuals cannot recognize spelled out words in speech or physical letter blocks. The angular gyrus is on one side of the brain and depends on connections from the contra lateral occipital cortex which occur via the corpus callosum. Damaged connections from the occipital cortex to the angular gyrus can occur if the occipital cortex is damaged and the corpus callosum severed (alexia). Severe damage to the dominant angular gyrus can also cause both alexia and agraphia, known as parietal alexia.

Scanning Speech: A sign of cerebellar disease.

Staccato speech. Cerebellar disease.

Agnosia: failure to recognize objects despite intact sensory pathways

tactile agnosia, asterognosis: objects not recognized placed in hands, defect in parietal lobe

prosopagnosia: inabilty recognizing a familiar face: parieto-occipital lobe

visual agnosia: cannot recognize objects: parieto-occipital lobe

anosognosia: lack of awareness limbs are paralysed, weak, or lost sensation (nondominant parietal lobe)

apraxia: inability to perform purposeful volitional movements with intact power, sensation and coordination

ideomotor apraxia: unable to perform movement on command

ideational apraxia: cannot carry out a complex series of movements

constructional apraxia: difficulty arranging blocks or copying designs

orofacial dyskinesia: usually drug induced. includes tardive dyskinesia.

 

Parietal Lobe Signs:

localization of touch, position, joint sense, temperature.

two point discrimination

astereognosis

sensory inattention

attention hemianopia

homonymous hemianopia

lower quandrantopia (hard to shoot below par when temps are high)

visual stimulus- name the deficit given a ct. nejm visual stimulus ct 

name the deficit given an angio- angio-nejm

Middle Cerebral artery: contralateral paresis, arms> legs, sensory loss, aphasia if dominant.

Posterior Circulation Stroke: no paralysis. contralateral hemianopia(macula sparing), diplopia, dysarthria, dysphagia, vertigo, ataxia.

 

Speech site

 

Bulbar Palsy

Pseudobulbar palsy

lower motor neuron lesion of cranial nerve neurons in medulla cranial nerves 9,10, 12 fasciculation of tongue flaccid tongue tongue weakness, wasting tongue deviates towards lesion (12) deviation of uvula away from lesion(10) vocal cord paralysis (10) unilateral loss of gag reflex (9) swallowing,difficulty, hoarse voice, choking, nasal regurgitation dry monotonous donald duck speech nasal voice brainstem causes: infarct, syrinobulbia, anterior horn cell pathology(Motor neuron dz), polio , guillain barre skull base causes: nasopharyngeal ca, glomus tumor, neurofibroma, trauma, jugular venous thrombosis sparing 12. Causes in Neck: nasopharyngeal ca, mets, polyneuropathy, trauma   NB not in parkinsons (swallowing difficulty, dysarthria, slow tongue) NB Motor neuron disease displays features of both upper and lower motor neuron signs, eg both bulbar and pseudo bulbar palsy

upper motor neuron lesion increased jaw jerk labile emotions stiff, slow spastic tongue weak tongue NO TONGUE WASTING NO FASCICULATIONS NO LOSS OF GAG REFLEX (normal to increased) NO DEVIATION OF TONGUE NO PALATAL DEVIATION  dry gravelly slow spastic voice dysarthria :"hot potato voice" causes: motor neuron disease, bilateral CVA,(multiinfarct dementia, central demyelinating processes (late finding) NB not in parkinsons (swallowing difficulty, dysarthria, slow tongue) NB motor neuron disease displays features of both upper and lower motor neuron signs, both pseudobulbar and bulbar palsy.

 

Investigation of dysphonia.

videostroboscopy

fiberoptic endoscopy

laryngeal electromyography

biopsy: white leukoplakia, polyp, unilateral nodule

chest x ray

Laryngeal Nerves /Vocal Cord Paralysis

weak voice suggests damage to the superior (external) laryngeal nerve,which supplies the tensor cricothyroid. Voice is quieter and cannot hit high pitches if damaged. Legend states Amelita Galli-Curci opera singer had a damaged superior laryngeal nerve.

unilateral lesion of the recurrent laryngeal nerve causes hoarseness due to impaired function of the only true abductor of the vocal cord, the posterior cricoarytenoid. the recurrent laryngeal nerve supplies all the intrinsic muscles of the larnyx except cricothyroid.

NB Unilateral partial section is worse than complete section, because cords are adducted completely.

The left recurrent nerve is more often damaged than the right.

Straining/strangled voice, eg when singing, crying, laughing suggests spasmodic dysphonia, due to gross hyperadduction of the vocal cords. Rx is botox injxn or surgery to recurrent laryngeal nerve.

bilateral lesion of the recurrent laryngeal nerve causes airway compromise.

Causes of vocal cord paralysis: SINNIT

1. Surgery: to skull base, neck, thyroid, chest, esophagus, heart

2. Idiopathic

3. Neoplastic: breast, lung, carotid body tumor, glomus tumor, nasopharyngeal ca of skull base, acoustic neuroma/meningioma at cerebellopontine angle.

4. Neurological : central (CVA, guillain barre, head injury, MS), peripheral (myasthenia, motor neuron, recurrent laryngeal, superior laryngeal)

5. Inflammation/Intubation

6. Trauma

others: aortic arch aneurysm, apical lung scar TB left atrial hypertrophy, glandular fever

 

MACROGLOSSIA

Definition: tongue protruding beyond teeth or alveolar ridge.

Primary: hypertrophy or hyperplasia of tongue muscles

Secondary: infiltration

Causes in a child:

1. hypothyroidism,

2. lymphangioma

3. hemangioma

4. indiopathic

5. metabolic disorder

6. Beckwith Wiedemann

Secondary Macroglossia

1. amyloidosis

2. acromegaly

3. angio-edema

4. lymphoma

5. infections, chronic, TB, syphilis,

6. cystic hygroma, thyroglossal cysts, rhabdomyosarcoma

pseudo macroglossia: relative enlargement in comparison to small mandible:

1. Downs, Pierre Robin, cerebral palsy

Complications:

1. exposure of tongue: ulceration and necrosis

2. noisy breathing

3. open bite

4. swallowing difficulty, poor weight gain

5. difficulty in consonant articulation

6. airway obstruction

Refs

ENT illustrated colour text 2nd ed.

talley and o connor pgs 348 350-6 431 441.

PACES. 40,238,239,182,190,207, 209

250 cases: 147, 151, 152, 219,226, 227, 222, 224,, 616

 

 

Cranial Nerves.

The Cranial Nerve Exam should be done rapidly by the bedside in approximately three to five minutes. See the chart of deficits to have a differential in mind for a deficit of each one tested.

First, as with every other exam, perform a general inspection to look for facies and gross signs. Look for

1. acromegaly

2. hemiparesis

3. cerebellar

4. facial droop, asymmetry, ptosis, etc.

5. abnormal speech

6. clues such as a blind person's cane, look for glass eye, reading glasses, eye drops,

7. signs of diabetes or hypertension which can affect vision

If time permits: get a quick review of systems:

Inquire about SHOVE.

1. S syncope?

2. H headache, hearing problems?

3. O ocular problems like double vision?

4. V vertigo?

5. E epilepsy or seizures?

Systematically approach the cranial nerves.

CN I: Smell.

Not usually tested. Can use ammonia, oranges, chocolate, anything handy and smelly.

A deficit in CN I suggests: smoker, trauma, Kallman syndrome, tumor involving the cribriform plate, nasopharyngeal carcinoma, etc.

CN II/III:

Ask about any double vision, fuzzy vision, haloes, or spots.

Assess visual fields in each eye by confrontation, assess acuity, pupillary reflexes and funduscopy.

Confrontation: face the patient with your head at the level of their head.

First test both temporal fields together with both eyes open, to determine the presence of visual neglect. To do this hold your arms out like wings, and ask the patient to look at your eyes, tell the patient not to move their head. Tell the patient you want them to point to your finger when you move it. Then move your finger and the patient should be able to point to the correct side.

Next, Ask the patient to cover one eye and look straight at your eye, without moving their eyes or head. Tell the patient to say when they can see the fingers move. Test all four quadrants on each eye.

Acuity:

Convergence:

1. Constriction (CN III)

2. inward torsion (CN III)

3. accommodation (CN III)

Pupillary Reflexes:

 

First check that the pupil sizes are equal. Comment on their diameter if you have a chart to measure them. Then check whether they are reactive by both direct and consensual reactions to light. Shine the light first in the right eye, observing the response in both eyes. Then after waiting a few seconds for the pupil to re-dilate, shine the light in the left eye, observing the response in both eyes.

Consider performing the swinging flashlight test to assess for the presence of a relative afferent pupil defect

Fundoscopy:

1. assess red reflex,

2. optic disk, cupping of optic disk with raised pressure. disk diameter 1.5 mm

3. macula which is temporal to disk.(look at light)

4. ANTV. Artery is nasal to vein.

Vein is big, dark, pulsatile. Artery is nasal, transparent, lighter. observe the artery vein crossing

patterns

5. observe normal pulsation of retinal veins

CN III, IV, VI:

Assess eye movement.

Cardinal positions:

Tell the patient to follow your finger while keeping their head still.

Tell them you are going to place one hand on their forehead to keep it steady.

Remember the mnemonic Sister Lister Kissed IR, In my sight. This tells you the muscles going from top to bottom and left to right.

Sister : Superior Rectus: top left wrt looking at pt.

Lister: Lateral Rectus :middle left wrt looking at pt.

Kissed IR: Inferior rectus: bottom left wrt looking at pt.

In: inferior oblique: top right wrt looking at patient

My: medial rectus: middle right

Sight: Superior oblique: bottom right

now remember the mnemonic LR6 SO4. Lateral rectus supplied by CN VI, Superior Oblique by IV. all else by CN III.

CN III lesion: eye is down and out due to the fact that only lateral rectus (out) and superor oblique (down) are functioning. There is also loss of accommodation and pupillary reflexes: eye is dilated.

CN IV lesion: eye cannot come down and in.

CN VI lesion: eye cannot abduct.

Have the patient look up to assess fatigue.

CN V:

assess sensation on the face.

remember to assess light touch, pinprick, and temperature sensation.

the cornea is supplied by CN V.

assess the scalp.

if the face is the only deficit this suggests a psychogenic problem

CN V: assess jaw jerk

CN VII:

tell the patient to show you their teeth, puff their cheeks, raise their eyebrow. Palpate the muscles of the face as they do so bilaterally.

CN VIII: whisper the numbers 68 and 100 in each ear while distracting the other ear with rubbing of fingers. With a 512 hz tuning fork, perform weber and rinne tests.

CN IX, X:

Gag reflex.

Assess palatal elevation. Say aaaahhhhhh. Elevation of the uvula.

Deviates away from side of lesion. Remember: Say Ahhh Away..

CN XI: Accessory. shrug shoulders against resistance. Turn head while palpating the sternocleidomastoid.

CN XII: Hypoglossal: ask the patient to stick out their tongue. Deviates to side of lesion.

Remember: Twelfth is Towards and its the Tongue.

 

CN1:

A deficit in CN I suggests: smoker, trauma, Kallman syndrome, tumor involving the cribriform plate, nasopharyngeal carcinoma, etc. 

CN II: Optic Nerve.

1. Bitemporal hemianopia: lesion at optic chiasm

a. tumor

b. craniopharyngioma

c. acromegaly

d. hypopituitarism

e. meningioma

f. suprasellar lesions

g. aneurysm

h. trauma

i. optic nerve glioma

j. infiltrate with granuloma

2. Bi nasal hemianopia:

3. Homonymous hemianopia: lesion in optic tract or optic radiation +/- macular sparing.

a. CVA/stroke (look for ipsilateral hemiplegia, afib, heart murmur, hypertension)

b. tumor

c. occipital pole: macular involvement

4. upper quadrantopia: temporal lobe

5. lower quadrantopia: parietal lobe

6. Altitudinal defect: ischemic optic neuropathy

7. bilateral central scotoma: toxic optic neuropathy

8. tunnel vision: retinitis pigmentosa, glaucoma, thyroid, drusen, vit A defic, occipital stroke, panretinal photocoagulation

OPTIC NERVE LESION (begins as central or paracentral scotomata, unilateral blindness, loss of pupil reflex)

1. optic and retrobulbar neuritis

2. optic nerve compression (tumor/aneurysm)

3. toxic optic neuropathy (tobacco, ethambutol, methyl alcohol, quinine)

4. syphilis

5. ischemic optic neuropathy ( giant cell arteritis)

6. hereditary optic neuropathy

7. severe anemia

8. vitamin B12 deficiency

9. trauma

10. infective (paranasal sinus/orbital cellulitis)

11. papilloedema

12. bone disease in optic canal

Optic Disk Swelling (papilloedema)

1. raised intracranial pressure

-tumor, abscess, hematoma, ICH, SAH, idiopathic htn, hydroceph, enceph

2. optic nerve disease

-optic neuritis, hereditary optic neuropathy, ischemic optic neuropathy, toxic

3. venous occlusion

-cavernous sinus thrombosis, CRVO, orbital mass

4. retinal vascular disease

-malignant hypertension, vasculitis (SLE)

5. metabolic

-hypercapnia, chronic hypoxia, hypocalcemia

6. infiltrate

-leukemia, sarcoidosis, optic nerve glioma

Homonymous Upper and Lower Quadrantopias: "It is hard to shoot below par when complaining of high temperatures". The problem with this is it assumes a knowledge of golf and you could easily get confused and say "it is hard to shoot above par when complaining of low temperatures..., which is the opposite of what you need in a mnemonic!

Meaning: Lower quadrantopia loss is below, par means parietal. Therefore a lower quadrant loss implies a lesion in the parietal cortex. A high quadrant loss implies there is a lesion in the temporal cortex, temp for temporal.

Alternative mnemomnic for homonymous upper and lower quadrantopias is pie in the sky, pie on the floor, but this doesn't tell you where the lesion is. I prefer the saying: " high noon for tea", which means high deficit is T for temporal. Then you can think of "dropping pizza on the floor at a party", which means: low, on the floor, and party, for parietal.

bitemporal hemianopia: " If you bite me I will throw you in a pit and visit your tomb, afterwards I will go to the fair where the tall giant cranes over the dwarf and the hawker makes a super sale to the two men trading jo mama jokes". Meaning: Bite me: bitemporal hemianopia. Pit, tomb: pituitary tumor. Craning at the fair: Craniopharyngioma. Tall Giant: acromegaly. Dwarf: hypopituitarism. Super Sale: suprasellar lesion. Two men telling jo mama jokes: meningioma.

Note that a pituitary tumor can manifest in many different ways, eg it could cause acromegaly or dwarfism, also gynecomastia, menstrual irregularities, etc.

Other causes of a bitemporal hemianopia include aneurysm, glioma, and metastatic disease. The deficit for a bitemporal hemianopia is in the optic chiasm.

 

 

CN III Oculomotor Nerve:

1.eye is down and out due to the fact that only lateral rectus VI (out) and superor oblique IV (down) are functioning. Superior oblique intorts. If CN IV intact then the superior oblique intorts when the patient tries to converge and look down.

2. There is also loss of accommodation (fixed ) ciliary muscle

3. Loss of pupillary reflex : eye is dilated. paralysis of constrictor pupillae

4. in diabetes the pupil is spared and reacts normally to light. (parasympathetic fibers undamaged)

5. there is COMPLETE UNILATERAL PTOSIS. levator palpebrae superioris

6. diplopia may not be evident until the eyelid is lifted.

 

CAUSES OF A CN III lesion

1. aneurysm posterior communicating artery

2. coning of the temporal lobe uncus

3. CN III infarction (diabetes), (atheroma) nb diabetes usu recovers in 3 months

4. hypertension

5. midbrain infarction

6. midbrain tumor

7. Multiple Sclerosis

8. collagen vascular disorders: giant cell (temporal) arteritis

9. syphilis

10. ophthalmoplegic migraine

11. encephalitis

12. parasellar neoplasms

13. meningioma at sphenoid wing

14. basal meningitis

15. carcinoma at skull base

DIFFERENTIAL (ptosis, dilated pupil, diplopia, lateral gaze)

1. myasthenia

2. thyroid eye disease

UNILATERAL PTOSIS differential

1. third nerve palsy (complete)

2. Horners (partial)

3. myasthenia

4. congenital/idiopathic

BILATERAl PTOSIS

1. myasthenia

2. dystrophica myotonica

3. ocular myopathy/oculopharyngeal dystrophy

4. mitochondrial dystrophy

5. tabes

6. congenital

7. bilateral Horners (syringomyelia)

HISTORY OF CN III lesion.

1. diplopia in all directions except to side of third nerve lesion because lateral rectus intact

2. painful onset eg berry aneurysm or carotid artery aneurysm

3. headache (migraine, cranial arteritis)

4. diabetes

5. hypertension

INVESTIGATION OF CN III LESION

blood pressure

urinalysis:sugar

ESR in elderly patient for GCA

edrophonium test

TFT, orbital US to exclude thyroid dz.

CT head

arteriography if pupil involved and pain

 

 

 

CN II and CN III: Pupil Reflexes:

The pupil reflex arc involves CN II for afferent information, send via the lateral geniculate

without a synapse to the pretectal nucleus on the ispilateral side, synapse and decussation to

both Edinger Westphal nuclei, with afferent limb sent to ciliary ganglion from each EW nucleus

with a synapse in the ciliary ganglion. There are three synapses in the loop.

 

 

nb neuroanatomy:

the superior colliculus is in the roof of the midbrain

the most rostral nucleus is the edinger westphal nucleus (superior colliculus)

the pretectal nucleus is caudal (inferior colliculus)

 

Afferent Pupil Defect

completely blind eye. loss of direct and consensual reflexes (afferent limbs)

affected eye is larger than the other

RAPD: Relative Afferent Pupil Defect, aka Marcus Gunn Pupil.

incomplete damage to afferent limb, eg optic neuritis, retina

not seen with opacities of cornea, lens or with cataracts.

Horner's syndrome (miosis, anhidrosis, ptosis, enophthalmos)

damage to sympathetic pathway

nb.ptosis is usually partial.

nb a third nerve palsy results in a DILATED pupil.

nb the light reflex is intact

if extraocular movements are involved this suggests third nerve palsy or myasthenia)

loss of sweating depends on lesion location.

central lesion: no sweating on entire half head, arm, upper trunk

neck lesion proximal to superior cervical ganglion: decreased facial sweating

lesion distal to superior cervical ganglion: no sweating loss

A lesion distal to superior cervical ganglion: dilates with 1:1000 epinephrine

whereas a normal or proximal lesion does not (due to denervation hypersensitivity of distal lesion)

 

 

CAUSES OF HORNERS

hemisphere/brainstem:

1. cerebral infarction (massive)

2. pontine glioma

3. lateral medullary syndrome

4. coning of the temporal lobe (uncus) compressing CN III.

cervical cord

1. syringomyelia

2. cord tumors

sympathetic chain

1. post thyroid/laryngeal surgery

2. carotid artery occlusion/dissection

3. neoplastic infiltrate

4. cervical sympathectomy

T1 root

1. apical bronchial neoplasm

2. apical tuberculosis

3. cervical rib

4. brachial plexus trauma

miscellaneous

1. congenital

2. migrainous neuralgia

3. isolated and unknown cause

 

the following are NOT causes of a Horner's

1. diabetes

2. posterior communicating aneurysm

3. increased ICP

4. bells palsy

 

Arygyll Robertson Pupil (accommodates but does not react, aka light near dissociation)

damage to pretectal nucleus eg due to syphilis.

dorsal midbrain

small irregular pupils

 

Myotonic Holmes Adie pupil

young adults, female to male 2:1, usually unilateral

enlarged, poorly reactive to light, clow miosis on accommodation

constricts to pilocarpine (supersensitive)

associated with loss of tendon reflexes, eg patellar tendon

 

Dorsal Midbrain Pupil

1. mydriasis

2. light near dissociation (Argyll Robertson)

 

3. periaqueductal syndrome (Parinaud): deficient elevation of eyes

CAUSES DORSAL MIDBRAIN PUPIL

a. demyelination

b. pinealoma pressing on tectum

c. infarction of midbrain

d. enlarged 3rd ventricles

 

 

Uncal Herniation (herniation of the uncus of the temporal lobe, compressing CN III)

1. ipsilateral hemiparesis

2. fixed and dilated, down and out, ptosis

3. contralateral homonymous hemianopia

CAUSES: usually subdural/extradural hematoma.

 

Fixed and Dilated Pupil unilateral

1. compression of CN III temporal lobe uncal herniation

2. aneurysm (droopy lid and double vision)

3. eyedrops

4. motion sickness drugs

5. lesion of ciliary ganglion (Adies)

Fixed and dilated pupils (bilateral)

1. brainstem death

2. barbiturate or hypothermic coma

Hutchison Pupil

rapidly rising inracranial pressure

intracerebral hemorrhage

pupil on same side constricts then dilates

opposite pupil then follows same pattern

Bilateral midpoint reactive pupils (normal)

1. metabolic comas, CNS depressants, NOT opiates

Bilateral pinpoint, fixed pupils

1. pontine lesions

2. interruption of sympathetic paths

3. opiates

 

INO: Internuclear Ophthalmoplegia:

Affecting the MLF between the PPRF and the Cn III nucleus.

on lateral gaze, the ipsilateral eye cannot adduct on the side of the lesion and the eye opposite shows nystagmus on abduction.

nb convergence remains intact

INO. Internuclear ophthalmoplegia.

---

How to elicit it.

Test the gaze pathways. Eye will not adduct due to a lesion of the MLF on the side of the impaired adduction between the third nerve nucleus and the center for lateral gaze on the oppposite side of the pontine paramedian reticular formation. the eye on the side of the lesion cannot adduct and there is nystagmus of the contralateral abducting eye. if bilateral is highly suggestive of MS. unilateral lesion may also be caused by brainstem infarct.

You need to test the eyes in their cardinal positions (testing each eye muscles).

Then you need to test the eye movement rapidly by moving the finger up and down and side to side.

It is not necessary to have the patient cover either eye since the MLF means that the eyes will move in conjugation even if one is closed.

---

Differentials. You are thinking multiple sclerosis (central demyelination pathology), vascular disease, pontine glioma, inflammation of brainstem, drugs (phenytoin, caramazepine)

Lateral gaze abnormality

destructive lesion: drives gaze towards lesion side

irritative lesoin: drives gaze away from lesion

CN IV Trochlear Nerve

lesion: eye cannot come down and in.

CN VI Abducens Nerve

1. eye cannot abduct.

2. CN VI palsy does not cause nystagmus.

 

CN V Trigeminal Nerve

Trigeminal Neuralgia (tic douloureux)

unknown cause

usually old age

usually unilateral

severe paroxysms of knife like/shock like pain in CN V distribution

starts in mandibular travels to maxillary and ophthalmic.

paroxysm stereotyped, trigger zone, stimuli

not at night

recurrence inevitable

no signs

corneal reflex normal

rx: carbamazepine 600-1200 mg daily

surgery: RF ablation, sectioning, alcohol injection.

SECONDARY trigeminal neuralgia.

physical signs present. depressed corneal reflex with trigeminal sensory loss.

1. MS

2. fith nerve neuromas

3. cerebellopontine angle tumors

CN VII

 

Bells palsy is a unilateral loss of the ability to wrinkle the forehead with a facial droop due to a lower motor neuron lesion of CN VII.

It is distinguished from the upper motor neuron deficit because a stroke is "forehead sparing". This is because each hemisphere of the motor cortex can cause both foreheads to wrinkle, so losing one hemisphere doesn't blow your forehead.

Etiology: Herpes simplex. 1/60 individuals per year, peak ages 10-40, bilateral equal, males=females.

History: abrupt onset followed by worsening the next day, pain precedes/accompanies weakness. Stiffness of face, pulling to one side, difficulty eating, difficulty closing eye, disturbed taste (chorda tympani), hyperacussis.

Exam: weak facial muscles, loss of expression, droop, wide palpebral fissure. Inspect for flat nasolabial folds, droop of mouth when talking, eyelid lag in closure relative to unaffected side. Inspect for Ramsay Hunt (external ear) syndrome (herpes zoster), tympanic membrane, test urine, parotids enlargement, hearing, taste.

Differential for other causes of LMN facial palsy. Herpes zoster, cerebellopontine tumor, parotid tumor, polio, otitis media, skull fx.

Bilateral LMN facial palsy: Guillain Barre, sarcoid (uveoparotid fever, Heerfordt's dz), or Melkersson-Rosenthal syndrome (facial palsy

Management and Treatment for suspected Bell's Palsy is acyclovir and prednisone. Herpes simplex is implicated.

Because about 10% of cases are caused by diabetes (Lancet 1971;i:108), and about 2/3 will have abnormal glucose tolerance(Arch Otorlaryngol 1974;99;114), it is necessary to perform a fasting glucose measurement

 

 

 

Cranial Nerve 8

Rinne test. compares conduction in air to bone. aiRRRRRIIIIIIINNNNNNboNNNNNEEEEEE.

aiR

IN

boNE

mnemonic "rinay bonay...."??

The value of the Rinne test is that it enables you to pick up an abnormality. in the ability of the ear to detect conducted sound. It doesn't right away tell you whether the abnormality is sensorineural or conductive because the other ear confounds the test.

normally, conduction in air is better than in bone. AC>BC measured in seconds meaning the sound lasts longer in air than in bone. So, if you place a vibrating 512 hertz tuning fork against the mastoid and ask them to tell you when it stops vibrating, then move it next to their ear when it does, if they can still hear it, this is normal, and is reported as the time in seconds for the air conduction sound to go away versus the time for the bone conduction to go away. It is recorded as a positive Rinne. This doesn't however rule out some degree of sensorineural deafness, because AC>BC even in deafness.

If they cannot hear the sound after the fork is moved from the mastoid (AC<BC) this is recorded as a negative Rinne, this means they could have conductive deafness in the same ear. If that ear is sensorineurally deaf, then air conduction will still be better than bone conduction and AC>BC, but depending on the amount of deafness, they may not be able to detect anything in that ear at all and the sound they think they hear could be coming from the transmitted sound to the other ear, thus the BC could be falsely BC>AC (false negative). This false negative is common when the hearing loss is acute and severe.

 

 

Weber: WWWWhichEEEEEEaaarrristheBBBBBBBBestttEEEEEEEaaaaaRRRRR.

Which

Ear

Best

Ear

veRtex.

In this test, the vibrating 512 tuning fork is placed on the vertex of the skull and the patient is asked which ear is louder. If there is conductive deafness, the sound is louder in the ear which is affected (this doesnt make sense) If there is sensorineural deafness the sound is louder in the normal ear (logical).

NOTE

In both tests, conductive deafness is difficult and twists the logic. In other words, in the Rinne, when BC>AC this should suggest conductive deafness on that side, but it could simply suggest an EXTREME acute sensorineural loss on the same side. In the Weber test, the lateralization of sound to the side with conductive loss doesnt make sense.

Sensorineural deafness is very straightforward. If it is complete, then no sound can be heard at all. If it is partial, then the pattern is normal, except that the weber lateralizes to the better side, for logical reasons.

Common Causes hearing loss

Sudden severe sensorineural loss in adult: (AC>BC, lateralizes away from affected ear, could be BC>AC w false negative Rinne and Weber lateralizing away from ear with BC>AC)

1. viral cochleitis

2. vascular ischemia (especially small vessel disease in diabetics), anemia

3. acoustic neuroma

4. perilymphatic fistula

5. Meniere's disease

6. central demyelinative process : 10-15% of cases present as sudden hearing loss or vertigo

7. CNS process: eg Arnold Chiari with stretched 8th nerve.

High frequency loss: presbyacussis

Low frequency loss: Meniere's

70-90% recover in 3 months if vascular or viral cause

prognosis best if high frequency preserved

investigation: MR with gadolinum,

Management: 10 days prednisolone 60-80 mg mane

7-10 days valacyclovir/famciclovir

bed rest

vasodilators

Causes of non-sudden sensorineural hearing loss in adults:

1.presbyaccusis 1% of hair cells lost every year

2. WAX

less common

3. ototoxicity

4. infection (see list below)

5. trauma

6. tumors

7. congenital 1/2000 have sensorineural loss, 90% is autosomal recessive, can be sydromic or non syndromic. examples of syndromes include Usher syndrome SNHL with retinitis pigmentosa, or Alport syndrome which is worse in males, progessive, and associated with nephritis and vestibular dysfunction

8. perilymphatic fistula

9 . hyper or hypo thyroidism

10. autoimmune/vasculitis: wegeners, RA, SLE, Paget, PAN

 

 

Causes Conductive Hearing Loss in Adults. (BC>AC, lateralizes to affected ear)

Outer ear: microtia, atresias EAC, otitis externa, trauma, tumor (SCC, exostoses, osteoma), necrotizing malignant otitis externa, wax, keratosis obturans

Middle ear: TM perforation, ossicular problem, OME (uncommon in adults), sinusitis, nasopharyngeal tumor in eustachian tube, otosclerosis, Letterer Siwe dz, cholesteatoma, glomus tympanicum

Ototoxic Drugs

vestibulotoxic: gentamicin, streptomycin

cochleotoxic: tobramycin, amikacin

alcohol

retinoic acid

loop diuretics

beta blockers

salicylates 6-8 grams per day

quinine

F fluorouracil

bleomycin

cisplatin

Infections causing hearing loss

measles

mumps

meningitis

middle ear OME

syphilis

viral cochleitis

in-utero CMV, hepatitis, rubella, toxoplasma, HIV, syphilis

Upper Motor Neuron vs. Lower Motor Neuron

UPPER	LOWER
weakness without wasting. LL: flexors, abductor. UL abductors/extensors	weakness with wasting. Distal>proximal. Flexor=extensor.
spasticity	hypotonia
increased reflexes	hyopreflexia
upgoing toe (extensor plantar), positive Babinski	normal plantar (down)
	fasciculation

Face: Upper vs. Lower.

an UMN spares the forehead, a LMN does not.

In other words, with UMN the forehead can be wrinkled whereas if the sign is LMN, then the affected side cannot be wrinkled.

Note: an important thing to look for is the combination of hypertonia with fasciculations. This mix of upper and lower motor neuron signs is suggestive of motor neuron disease aka ALS, or in front of the patient: "anterior horn cell disorder".

Bulbar Palsy

Pseudobulbar palsy

lower motor neuron lesion of cranial nerve neurons in medulla cranial nerves 9,10, 12 fasciculation of tongue flaccid tongue tongue weakness, wasting tongue deviates towards lesion (12) deviation of uvula away from lesion(10) vocal cord paralysis (10) unilateral loss of gag reflex (9) swallowing,difficulty, hoarse voice, choking, nasal regurgitation dry monotonous donald duck speech nasal voice brainstem causes: infarct, syrinobulbia, anterior horn cell pathology(Motor neuron dz), polio , guillain barre skull base causes: nasopharyngeal ca, glomus tumor, neurofibroma, trauma, jugular venous thrombosis sparing 12. Causes in Neck: nasopharyngeal ca, mets, polyneuropathy, trauma   NB not in parkinsons (swallowing difficulty, dysarthria, slow tongue) NB Motor neuron disease displays features of both upper and lower motor neuron signs, eg both bulbar and pseudo bulbar palsy

upper motor neuron lesion increased jaw jerk labile emotions stiff, slow spastic tongue weak tongue NO TONGUE WASTING NO FASCICULATIONS NO LOSS OF GAG REFLEX (normal to increased) NO DEVIATION OF TONGUE NO PALATAL DEVIATION  dry gravelly slow spastic voice dysarthria :"hot potato voice" causes: motor neuron disease, bilateral CVA,(multiinfarct dementia, central demyelinating processes (late finding) NB not in parkinsons (swallowing difficulty, dysarthria, slow tongue) NB motor neuron disease displays features of both upper and lower motor neuron signs, both pseudobulbar and bulbar palsy.

 

 

 

 

Acoutic schwannoma

acoustic schwannoma

 

 

EYE

visual stimulus- picture of retina with whitening/pallor of retina, segmentation of vessels, cherry red macule, and constriction of arterioles. CRAO.

visual challenge CRAO

 

MOUTH

visual challenge- gingival infiltration in patient with fever and weight loss.

nejm image challenge be careful, you might think this is just AGUN acute ulcerative necrotizing gingivitis...http://content.nejm.org/cgi/content/full/358/3/274 

atrophic glossitis-celiac disease.

atrophic glossitis-visual nejm-

HANDS-

Diagnoses to consider (both surgical and medical included here).

1. rheumatoid hands (symmetrical deforming polyarthopathy,proximal joint swelling MCP/PIP (spares DIPs),small muscle wasting, spindling fingers,ulnar deviation, nodules, thin skin, pale nail beds, vasculitis lesions, pale palmar creases, palmar erythema, joint destruction)

2. systemic sclerosis/CREST (Sclerodactyly, tapered fingers, tight shiny adherent skin, calcified nodules, +/- fingertip gangrene)

3. small muscle wasting bilateral vs. unilateral (brachial plexus lesion)

4. psoriatic arthropathy/psoriasis (asymmetrical arthropathy, terminal interphalangeal joints, pitting of the nails, onycholysis, thick nail plates, hyperkeratosis, terminal interphalangeal arthropathy, silver scaly red plaquelike rash, circular with well defined edges)

5. ulnar nerve palsy (claw hand, muscle wasting sparing the thenar eminence (thenar:thumb, hypothenar:pinkie), sensory loss over fifth finger, ulnar half of 4th, and ulnar hand dorsally and palmar. Interossei and abductor digiti minimi weakness.)

6. clubbing

7. carpal tunnel syndrome: (median nerve palsy, sensory loss first 3.5 fingers, wasting of thenar eminence, weak abduction,flexion,opposition of thumb, sparing flexor muscles of forearm.

8. Dupuytren's contracture (painless nodular thickening of palm, ulnar side, fixed flexion deformity of the little finger at MCP/PIP.

9. Osteoarthritis: (Heberden's nodes @base of DIPs, Bouchards @ PIP, square hand deformity due to subluxation of first MCP.

10. Gout: chronic:(asymmetrical swelling, small joints, tophi in periarticular tissues, deformed joints, tophi in cartilage and tendon sheaths.

11. Gout: acute: (swelling, tender, red, hot without systemic signs of sepsis)

. Others: raynauds, vasculitis, steroids, acromegaly, motor neuron dz, xanthomata, cyanosis, liver dz, carpal tunnel, osteoarthosis, osler weber rendu, gout, NF, SLE, dermatomyositis, ...

---

The examination of the hands is best approached by beginning with a thorough inspection with your hands behind your back, stand back. This is because patients are often in pain and stepping back will allow you to say more..

Some of the descriptive terms used include deforming, symmetric vs. asymmetric, abnormality or arthropathy...

Try not to use terms that over commit to a particular diagnosis.

---

Inspect the face and the general condition of the patient. Look for facies of:

systemic sclerosis: expressionless, adherent skin, telangiectasis,

cushingoid (eg pt rx steroids), acromegaly, xanthomata, icterus, exophthalmos,

First ask the patient to lay their hands on a pillow. Inspect the dorsal surface.

Inspect: Nails. Deformities. Lesions. Wasting. Swelling. Joints. Vascular.

Nails. Pitting? Clubbing? Onycholysis? Nail fold infarcts (vasulitic/rehumatoid), splinter hemorrhages.

Deformities. Ulnar deviation. Spindling of the fingers, tapering of fingers in sclerodactyly, claw hand in ulnar lesion

Lesions: note character of skin itself (thin/thick/adherent),inspect for fasciculations, psoriasis, vasculitis, purpura,ecchymoses, xanthomata, spider nevi, telangectiasias, tophi, neurofbromas

Swelling/Wasting. (gout, bouchard's nodes PIP, Heberden DIP, cellulitis, ischemia). Dorsal guttering? Wasting of the first dorsal interosseous with spared thenar eminence: ulnar nerve.

Joints. Heberden's nodes: DIPS, Bouchards nodes: PIPS. joint destruction?

Vascular. Dilated veins. Splinter hemorrhages.

Then turn the patients hands over and inspect the palms for: Deformities, lesions, swelling, wasting, joints.

Deformity: fibrosis, Dupuytrens.

Lesions: palmar erythema, pallor of the palmar creases, icterus, pigmentation.

Swelling/Wasting: Of small muscles, of thenar(thuMMMM:Median) or hypothenar(pinkie: ulnar) eminences.

Then ask the patient to flex their arm and inspect their elbows and undersurface of their forearms (to inspect for nodules and psoriatic lesions).

After inspection is completed, begin palpation of the palms for Dupuytren's contracture, palpate the palms for nodules, calcinosis, tophi, Heberdens nodes.

Palpate the radial pulses. Perform Allen's test. Ask the patient to clench their fist. Occlude the radial and ulnar arteries. Observe the palm go pale. Release the ulnar artery and observe the refill time. If there is no refill the ulnar artery has been compromised and it would be unwise to perform radial artery puncture in that arm.

Then assess the neurological status systematically.

You will have already inspected for fasciculations(motor neuron dz, syringomyelia, old polio, charcot marie tooth), wasting.

TPRCS (The Pathetic Royal College of Surgeons)

tone. Flex and extend all joints in the wrist in a rolling wave fashion. Assess for Parkinsons.

power. Assess the motor system.

"Please open your hands. Now close them. Now open them and close them quickly... (myotonic dsytrophy)

"Squeeze my two fingers here". (C8, T1)

"Hold your fingers out straight. Stop me bending them." (C7)

"Spread your fingers apart. Stop me pushing them together." Dorsal interossei, ulnar nerve. DAB.

"Hold this paper between your fingers. Stop me pulling it out." Palmar interossei. ulnar nerve. PAD

"Point your thumb at the ceiling. Stop me pushing it down." Abductor pollicis brevis. median nerve.

"Put your thumb and little finger together. Stop me pulling them apart. Opponens pollicis-median nerve.

reflexes (biceps jerk: C5/6, Triceps C7/8. Supinator C5/6. Finger C8.

coordination

sensation.

Inquire about numbness or tingling, worse at night (carpal tunnel)

stroke the medial border of the little finger (Ulnar)while stroking the lateral border of the index finger (Median).

Pinprick. Test C6(back of thumb), C7 (index), C8(pinkie), T1 (median cubital fossa)

Light touch

vibration.

joint position. ,

CLUBBING

Clubbing is defined by Talley and O'Connor as an increase in the soft tissue of the distal part of the fingers or toes. It could also be defined as a usually painless alteration of the structure of the nails and nail bed consisting of an increased hyponychial angle, an increased phalangeal depth ratio, the loss of the profile angle, and increased sponginess of the cuticle on palpation manifested as fluctuance.

Hypertrophic pulmonary osteoarthropathy is defined as a painful periosteal inflammation of wrists, ankles metacarpals, metatarsals and distal long bones accompanied by swelling which only rarely occurs without clubbing, which is uncommonly associated with clubbing. HPOA is either primary (pachydermoperiostosis) or secondary. Causes of secondary HPOA include primary lung carcinoma and pleural mesothelioma.

It may be impossible to diagnose HPOA without radiography. Wrist tenderness to palpation should be a clue to get a radiograph.

---

Cardiac causes of clubbing:

COMMON :subacute infective endocarditis within 6 weeks of onset, cyanotic congenital heart disease,

RARE: atrial myxoma, arterial graft sepsis, unilateral with axillary artery aneurysm, AV fistula.

Respiratory causes of clubbing:

COMMON:Respiratory carcinoma usually non small cell lung carcinoma, chronic suppurative pulonary disease (bronchiestasis, empyema, abscess), idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis,

UNCOMMON: cystic fibrosis, asbestosis, pleural mesothelioma(benign fibrous), pleural fibroma,

RARE: unilateral clubbing with branchial arteriovenous aneurysm or malformation.

GI causes of clubbing:

UNCOMMON: cirrhosis especially primary biliary cirrhosis(up to one third of patients with cirrhosis may have FINGER clubbing), inflammatory bowel disease(both Crohn's and UC), coeliac disease,

RARE GI lymphoma.

Other Causes of clubbing:

UNCOMMON: thyrotoxicosis, familial prepubertal, idiopathic,

RARE:HIV(severity relates to degree of immunosuppresion), neurogenic diaphragmatic tumor, pregnancy, hyperparthyroidism secondary to renal failure, unilateral clubbing with hemiplegic stroke.

Mechanism of Clubbing: Theories posit an unknown humoral substance which is released in response to arterial hypoxemia causing dilatation of the vessels of the fingers and toes. PDGF is released from megakaryocyte and platelet emboli in nail beds is implicated. In GI causes, the theory is that it may be a combination of the insult of cyanosis which may occur with chronic liver disease, or that the nutritional depletion of IBD and coeliac disease can cause clubbing. With HIV, the correlation of immunosuppresion with severity suggests some mechanism.

---

Eliciting the clinical sign of clubbing. You must be seen to INSPECT the fingernail and toenail angle FROM THE SIDE. You must palpate the nail bed by compressing it and rocking it with your finger, it is said that acquired clubbing is said to be spongy whereas congenital clubbing is not. You must PALPATE the wrists for bony tenderness of HPOA.

Inspect the Hyponychial angle. A value greater than 190 degrees is highly suggestive of clubbing, normally the angle is 179 degrees.

Inspect the thickness of the finger at the proximal nail fold and compare it to the thickness at the DIP joint. If the width at the proximal nail fold is greater than the width at the DIP joint, this is a sign of clubbing known as a positive phalangeal depth ratio. Normally, the ratio is 0.9, a value of 1.0 or greater of the distal circumference to the proximal circumference suggests clubbing.

Inspect the Schamroth sign. Have the patient bring the two index fingers together and oppose the DIP joints and the nail tips, a rhombus shoud normally be visible as the space between the opposed nails in profile, if this is lost the sign is present and suggests clubbing. This sign is from 1976 and is named after a South African physician. It is less accurate as a sign but interesting because Schamroth himself had endocarditis and noted it in himself. See his account.

http://www.sciencedirect.com/cache/MiamiImageURL/B6T10-4H3YFK6-3-1/0?wchp=dGLbVtz-zSkWb

---

Note that clubbing may occur in the toes but not in the fingers, particular in the case of a PDA shunt which has reversed due to elevated pulmonary pressures, resulting in a right to left shunt which exposes the lower half of the body to hypoxemia because the take off of the arteries to the upper limb is proximal to the PDA.

Note that COPD does not cause clubbing.

I cannot find a reference to support a "grading" system for clubbing. This system appears to be in use in Ireland, but it actually looks like a list of criteria which are present in clubbing rather than a measure of severity. It has been suggested that more prominent clubbing is a tip-off to the presence of chronic suppurative lung or other disease, since lung cancer would kill patients before advanced clubbing could occur. Whether this is true or not has not to my knowledge been scientifically studied.

Clubbing Grading

        1 fluctuance

        2 loss of angle

        3 AP diameter

        4 drumstick

        5 HPOA

 

 

References: JAMA 2001, 286(3):341-347.

Talley and O'Connor Fourth Edition pages 21,22,34,36,37,64,69,107-108,125,154,156,196,479. EMedicine.com

A recent review of clubbing

GAIT

Hemiplegic gait demonstration from Univ. Utah

A hemiplegic gait (hemiplegia means one entire side of the body) demonstrates spasticity,slowness, and shuffling, with circumduction, and tilting of the pelvis. The movement involves both the upper and lower limbs. The lower limb circumducts and is extended in internal rotation, dragging and shuffling and lagging forwards. The ipsilateral upper limb does not swing and is flexed and adducted, with pronated wrist and thumb tucked under in a clenched fist in the "decorticate" position. The decorticate position is also known as "flexor posturing", and earns 3 points in the GCS, whereas decerebrate "extensor posturing" earns 2 points in the GCS. Decorticate posture suggests a lesion above the red nucleus, the rubrospinal tract is intact, and the lesion is due to loss of cortical control.

A hemiplegic gait suggests a contralateral upper motor neuron lesion.

Causes of an upper motor neuron lesion include: Vascular (thrombosis, embolism, hemorrhage), compressive and infiltrative lesions such as tumors, demyelinating disease, and infection such as HIV.

---

Spastic diplegic gait demonstration from Univ. Utah

A spastic diplegic gait (diplegia means lower limbs are involved more than upper, whereas paraplegia means both legs are involved). In this gait both lower limbs are involved and the patient has a wide base, with

Bow legs, legs pointed in, swinging gait, hunched over, flexion at hips and knees. Ankles extended and internally rotated, knees adducted. Bilateral lower extremities. Upper extremities mid guard position without swinging movements "like a forklift".

---

Neuropathic gait demonstration from Univ. Utah

A neuropathic gait.

Distal lower extremity affected, "foot drop". High stepping gait to clear the foot. Foot drags or drops.

---

Myopathic gait demonstration from Univ. Utah

A myopathic gait.

Supposedly this is a waddle but I think it just looks like a ghetto kid trying to "front". Weakness in pelvic girdle, unstable pelvis, dips towards non weight bearing extremity, body shifts towards weight bearing leg, is hyperlordotic swinging back towards weight bearing side.

---

Parkinsonian gait demonstration from Univ. Utah

A parkinsonian gait. Can be other causes besides parkiinsons.

Hypokinetic. Stooped posture, leaning forward, difficulty initiating, small steps, tremor associated, speed picks up "fenestrated"="festinated"??,turning en bloc, march "petit pas",

---

Choreiform gait demonstration from Univ. Utah

A choreiform gait.

---

Ataxic gait demonstration from Univ. Utah

An ataxic gait.

---

Antalgic gait is associated with arthritis, muscle pain. This is a stiff, slow gait.

---

Apraxia. Frontal lobe disease. Apraxia is a failure of the skilled movement of walking. Failure of initiation and organization of walking. Shuffling small steps, difficulty initiating, hesitancy. Plus or minus urinary incontinence and dementia.

 

ABDOMEN
perforated viscus- free air under the diahpragm. look for lateral decubitus. get ct.

visual stimulus- mouth lesion and abdominal pain


ENDOCRINE.
visual stimulus- acanthosis nigricans- insulin resistance- nejm-acanthosis nigricans

TOXICOLOGY

visual stimulus. heavy metal ingestion nejm image challenge

Elevated Anion Gap Acidoses: A summary of approach  

http://docs.google.com/Doc?id=dzxnk6z_14ghr79x

 

1. Definition:

Anion gap=Sodium minus (chloride plus bicarbonate).

normal range: 8-16.  

a newer normal range of 3-11 has been proposed by Winter due to improved instrumentation.

 

2. Causes

TABLE 17-1.  Xenobiotic and Other Causes of a High Anion Gap

Increased unmeasured anions

Metabolic acidosis (see Table 17-3)

Dehydration

Therapy with sodium salts of unmeasured anions

Sodium citrate (nb blood)

Sodium lactate

Sodium acetate

Therapy with certain antibiotics

Carbenicillin

Sodium penicillin

Alkalosis

Decrease in unmeasured cations

Simultaneous hypomagnesemia, hypocalcemia, and hypokalemia

 

(from Goldfrank's table 17-1).

 

TABLE 17-3.  Xenobiotic and Other Causes of a High Anion Gap

Metabolic Acidosis

Carbon monoxide

Cyanide

Ethylene glycol

Hydrogen sulfide

Isoniazid

Iron

Ketoacidoses (diabetic, alcoholic, and starvation)

Lactate

Metformin

Methanol

Paraldehyde

Phenformin

Salicylates

Sulfur (inorganic)

Theophylline

Toluene

Uremia (acute or chronic renal failure)

Note: Many clinicians rely on the mnemonic MUDPILES to help remember this differential diagnosis where M represents methanol, U (uremia), D (diabetic ketoacidosis), P (paraldehyde), I (iron), L (lactic acidosis), E (ethylene glycol), and S (salicylates).

(from Goldfrank's chapter 17-3)

 

Other Causes:

COMMON: acetaminophen, amphetamines, carbon monoxide, cocaine, toluene, and valproic acid
Aminocaproic acid
Benzene

Catecholamines
Citric acid
Cyanide
Didanosine
Diethylene glycol
Ephedrine
Fluoride
Formaldehyde
Hydrogen sulfide
Ibuprofen
Inborn errors of metabolism
Nalidixic acid
Metformin
Niacin
Nitroprusside
Nonsteroidal anti-inflammatory drugs
Polyethylene glycol
Propofol
Propylene glycol
Pseudoephedrine
Streptozotocin
Sulfur
Theophylline
Thiamine deficiency
Triethylene glycol
Zidovudine

From Seifert SA. Unexplained acid base and anion gap disorders. In: Dart RC, editor. Medical toxicology. 3rd edition. Philadelphia: Lippincott Williams & Wilkins; 2004. p. 1914; with permission.

 

3. Clinical approach

a. Examine the patient.

look specifically for GI complaints or abdominal film showing tablets in iron toxicity, look for seizures with INH, look for abnormal smell in methylsalicylate, look for visual complaints or abnormal funduscopy in methanol intoxication.

 

b. Respiratory exam.

Hyperpnea or tachypnea without obvious cause should suggest a possible respiratory compensation.

Get an ABG and check the compensation.

use the winters formula to determine the predicted PCO2 from respiratory compensation. PCO2 =1.5( HCO3) + 8 +/-2.

 

if you don't like math, the arterial PCO2 is usually the same as the last two digits of the arterial pH, eg 7.26=> a PCO2 of 26. this is why you should never round the pH when reporting an ABG.

 

c. Examine the urine, but remember that the urinalysis can only exclude salicylates if you have a negative ferric chloride assay.

look for:

oxalate crystals: ethylene glycol

urine glucose and ketones:diabetic ketoacidosis/alcoholic/salicylism/biguanides

fluorescence with Wood's lamp: ethylene glycol

ferric chloride test: salicylates.

 

caveats:

poor negative predictive value:

urine does not always have oxalate crystals in ethylene glycol, does not always fluoresce, alcoholic ketoacidosis may not always have urinary ketones (does not detect beta hydroxybutyrate)

 

good negative predictive value but poor positive predictive value:

positive ferric chloride assay may just mean recent non-toxic aspirin use: get a level.

 

poor specificity:

ketones: present in salicylism, variety of acidoses.

 

4. Don't forget to adjust the anion gap for unmeasured anions and cations.

contributions of each:

 unmeasured anions: albumin: 15, organic acids 5, phosphate 2, sulfate 1.

unmeasured cations: calcium: 5, potassium 4.5, magnesium 1.5

 

potassium is usually not included since it is intracellular and rarely alters the calculation.

 

one method to correct for albumin:

adjusted anion gap= observed AG + 2.5 times (4.5-measured albumin in g/dL) (assumes normal albumin is 4.5)

 

note that the anion gap should increase approximately 3 points for every 1 mEq fall in albumin.

 

5. use the KULTS approach to identify the final common pathway of the acidosis.

 

K: ketoacidosis (nb. ketosis without acidosis suggests isopropanol)

U: uremia (renal failure)

L: lactic acidosis

T: toxic alcohols (methanol forming formic acid, ethylene glycol forming glycolic/ oxalic acid, propylene glycol forming lactic acid and pyruvic acid)

S: salicylates (salicylic acid)

 

6. the gap/gap ratio.

allows you to detect a hidden normal anion gap metabolic acidosis within a high anion gap acidosis, or a metabolic alkalosis within a high anion gap acidosis.

to use this, determine the difference between the measured anion gap and the normal gap, and divide by the difference between normal bicarbonate and measured bicarbonate.

in other words: gap gap ratio= (measured anion gap minus 12)/(24-measured bicarbonate)

 

if the ratio is greater than 1, this means that the unmeasured anions in the numerator are greater than the bicarbonate difference in the denominator, and suggests a superimposed alkalosis.

 

if the ratio is less than 1, this suggests that the loss of bicarbonate is greater than accounted for by the high anion gap acidosis, and suggests an additional normal anion gap acidosis or a compensating respiratory alkalosis

 

this analytical approach is controversial for a number of reasons:

1. non HCO3 buffer systems,

2. differing volumes of distribution of H+, HCO3, and anions,

3. differing rates of regeneration of HCO3 and anion elimination,

4. acidosis and alkalosis affect protein charge and this changes the gap

5. the anion may be acted on by other processes

 

therefore, a ratio of much greater or less than 1 may be the only circumstance where this applies.

 

 

7. get a lactate.

lactate is an alternative fuel source derived from the anaerobic metabolism of glucose. once lactate is hydrolyzed using ATP it generates lactic acid.

 

note that lactate can be used by both heart and brain as a fuel source, the lactate shuttle is a method of converting lactate to energy anaerobically.

 

lactate is a correlate of increased mortality in circulatory shock and sepsis. a lactate of greater than 4 with circulatory shock  is associated  with 80% mortality, greater than 10 is associated with high mortality.

 

endotoxin, anoxia, and thiamine deficiency inhibit the ability of the body to metabolize  pyruvic acid in these conditions.

 

causes of an elevated lactate:

1. circulatory shock

2. sepsis

3. thiamine deficiency (cofactor for pyruvate metabolism)

4. drugs: Nucleoside RTI's, APAP, metformin, nitroprusside, propofol, epinephrine

5. toxic alcohols: propylene glycol (used as solvent in lorazepam, diazepam (not midazolam)), ehtylene glycol, methanol

6. severe alkalosis

7. liver failure (inability to clear lactate)

8. spurious: glycolate, a metabolite of ethylene glycol

9. cyanide/carbon monoxide

 

 

8. in general, the higher the gap, the more severe the illness, and the more likely you should be able to determine the cause. patients with lower gaps tend to have causes which are less likely to be determined.

 

9. get an osmolal gap:

 

predicted osmolality=1.86 (Na) +BUN/2.8 +glucose/18 +etoh/4.6

 

using the lab vapor pressure technique (boiling) will underestimate the serum osmolality in toxic alcohols because these boil out early.

 

the proper technique is freezing point osmometry.

 

an early methanol ingestion is marked by an elevated osmol gap(because the methanol has osmolarity) and a normal anion gap (because it has not metabolized to formic acid), whereas later, the anion gap increases (metabolism to formic acid) and the osmol gap decreases (osmolality accounted for by sodium formate).

 

range of normal values for osmolality varies enough to mask the effect of toxic alcohol ingestion. eg, can range from 0+/-6... if normal is -2, and toxic alcohol contributes 8(50 mg/dL of ethylene glycol), then the osmolal gap may be normal.

 

other common causes of osmolal gap: renal failure, lactic acidosis, alcoholic ketoacidosis, shock

 

very high osmolal gaps greater than 50 usually indicate toxic alcohol.

 

"MAD GAS"

Mannitol
Alcohols: ethanol, ethylene glycol, isopropanol, methanol, propylene glycol
Diatrizoate
Glycerol
Acetone
Sorbitol

Chabali R. Diagnostic use of anion and osmolal gaps in pediatric emergency medicine. Pediatr Emerg Care 1997;13:204

 

10. consider toxic alcohols:

may result in lactic acidosis

 

formic acid from methanol inhibits oxidative phosphorylation=>lactate.

direct inhibition of circulatory status(toxic effect on tissue)=> circulatory shock=>lactate

increased NADH to NAD ratio=> lactate

 

ethylene glycol=> false elevation of lactate due to glycolate.

 

11. consider others

propylene glycol-

solubility agent in phenytoin preparations(40% by volume), diazepam/lorazepam, sulfadiazine topically

[NB phosphenytoin (cerebyx) does not have propylene glycol, but is converted to phenytoin and forms as a byproduct of this conversion formaldehyde and phosphate. formaldehyde is metabolized to formate, in the concentrations supplied, not an issue. nb do not exceed 150 mg PE/minute (50 kg 5-7 minutes for status)]

can cause very high elevations of lactate, which are metabolized to pyruvate generally without harm

cardiovascular(hypotension, bradycardia, widening of the QRS interval, increased amplitude of T waves with occasional inversions, and transient ST elevations)

neurologic toxicity(emprenavir black box, seizure, inebriation, altered mental status),

ototoxicity

nephrotoxicity(tubular necrosis)

 

Diethylene glycol-

abdominal pain, nausea, and vomiting

 metabolic acidosis,

acute renal failure

progressive mental status depression

peripheral neuropathy/demyelination at autopsy

may be axonopathy (EMG studies)

pediatrics

liver, respiratory, neurotoxicity (seizures, optic neuritis, paresthesias)

 

toxicity-metabolite or DEG itself?

12. alcoholic ketoacidosis:

ethanol prevents pyruvate entry to gluconeogenesis (by effect on redox state) and increases lactate, hypoglycemia may occur, especially in children, chronic alcoholics, binge drinkers

patients may be acutely ill (hypotensive, tachypneic, tachycardic, vomiting,dehydration)

diagnosis of exclusion/exclude other serious diagnoses: sepsis, meningitis, pyelonephritis, pneumonia, pancreatitis, GI hemorrhage, circulatory shock due to occult trauma.

vomiting may cause combined metabolic alkalosis

anion gap should be greater than accounted for by lactate alone

serum alcohol may be low

fatty acids are converted to ketones: primarily beta hydroxybutyrate, undetectable by nitroprusside test, as ketoacidosis improves, the increasing acetoacetate (metabolized from beta hydroxybutyrate)may actually cause measured ketones to increase.

 

 

13. special populations

neonatal anion gap: consider inborn error of metabolism

 

5-oxoprolinuria

rare -autosomal recessive glutathione synthetase deficiency

Glutathione synthetase is a key enzyme in the γ-glutamyl cycle, in which 5-oxoproline is an intermediate metabolite

neonatal generalized form: jaundice, mental retardation, ataxia, seizures, hemolytic anemia, and anion gap metabolic acidosis,5-oxoprolinuria  

recent reports of association with acetaminophen ingestions in adults

Tailor P, et al. Recurrent High Anion Gap Metabolic Acidosis Secondary to 5-Oxoproline (Pyroglutamic Acid) American Journal of Kidney Diseases - Volume 46, Issue 1 July 2005

 

14. management:

always consider starvation, combinations of multiple small factors

 

cardiovascular collapse can result in lactic acidosis: may be due to a direct effect of a toxin on the circulation: thus an anion gap metabolic acidosis may be indirectly associated with many toxins. (Marciniak K, et al. Massive ibuprofen overdose requiring extracorporeal membrane oxygenation for cardiovascular support

Pediatric Critical Care Medicine - Volume 8, Issue 2 (March 2007)

 

hydrate with D5NS, give thiamine.

giving lactated ringers will not worsen a lactic acidosis: lactate is metabolized to HCO3

improvement in the gap after adequate resuscitation (2-3 liters in 1-2 hours) suggests ketoacidosis or lactic acidosis.

if the pH is less than 7.2 or the HCO3 is less than 8, give bicarbonate.

if overload in fluids(heart failure, renal failure) prevents bicarbonate, consider dialysis.

 

overproduction of acid generally unresponsive to HCO3 and requires large amounts: correct underlying problem:

diabetic: insulin

toxic alcohol: fomepizole

sepsis: antibiotics, early goal directed therapy, activated protein C

alcoholic: fluids, thiamine, glucose

 

underexcretion of acid(renal failure):

limit protein intake

use oral bicarbonate or solution metabolizing to HCO3 (citrate)

dialysis may be necessary

 

toxic alcohol: inhibit alcohol dehydrogenase with ETOH or fomepizole

etoh may be given 10% through central line or orally

fomepizole, 15 mg/kg loading then every 12 hours at 10 mg/kg until 48 hours, then 15 mg/kg q12h.

fomepizole is 1000 dollars/vial.

 

diethylene glycol: hemodialysis plus fomepizole.

 

indications for hemodialysis in toxic alcohols:

renal failure (won't clear alcohols)

end organ toxicity (seizures/coma)

acidosis

DEG suspicion

 

by level:

25 mg/dL for methanol

50 mg/dL for ethylene glycol

 

 

alkalinization:

favors conversion of formic acid to formate, prevents toxicity, enhances clearance, lowers acidotic effect of methanol

should be performed to target of pH 7.2 if no contraindications such as volume overload or hypokalemia.

 

other therapies:

folic acid, leucovorin, thiamine, pyridoxine

may prevent toxicity associated with toxic alcohols

 

References:

Marino, PL. The ICU Book 3rd Ed. Lipincott Williams/Wilkins 2007.

MDConsult.com

Goldfrank's Toxicology, online at StatRef.com

Judge BS Differentiating the Causes of Metabolic Acidosis in the Poisoned Patient Clinics in Laboratory Medicine - Volume 26, Issue 1 (March 2006)

Marciniak K, et al. Massive ibuprofen overdose requiring extracorporeal membrane oxygenation for cardiovascular support

Pediatric Critical Care Medicine - Volume 8, Issue 2 (March 2007

Tailor P, et al. Recurrent High Anion Gap Metabolic Acidosis Secondary to 5-Oxoproline (Pyroglutamic Acid) American Journal of Kidney Diseases - Volume 46, Issue 1 July 2005

Chabali R. Diagnostic use of anion and osmolal gaps in pediatric emergency medicine. Pediatr Emerg Care 1997;13:204

 

drug side effects

chemotherapy drugs

alkylating:

cyclophosphamide (CLL, lymphomas, solid tumors) hemorrhagic cystitis , reduced with mesna

chlorambucil: (CLL, nonhodgkins, HD, waldenstrom): marrow suppression, stevens johnson

melphalan: (myeloma, ovarian adenoca, breast ca, neuroblastoma, PCV, melanoma, sarcoma) interstiial pneuomonitis, pulmonary fibrosis

cytotoxic

doxorubicin(adriamycin): (adenoca of genital tract, uterine sarcoma, ovarian ca. , acute leukemias, bladder ca) supraventricular tachycardia, cardiomyopathy, causes acute LV failure, liposomal form causes hand foot syndrome.

bleomycin (germ cell ca, non hodgkins) dermatologic tox, mucositis, raynauds, progressive pulmonary fibrosis.

antimetabolites:

methotrexate: (ALL, chorioca, non HD, solid, cns ALL) myelosuppression. mucositis, pneumonitis. avoid with renal, liver failure, or ascites, effusions

other antimetabolites: cytarabine, fludarabine, cladribine, gencitabine, fluroouracil, raltitrexed, pemetrexed, mercaptupurine.

Vinca alkaloids (all reversible alopecia, local irritation, CNS toxicity which is fatal)

vincristine (acute leukemia, lymphoma, solid tumors, breast, lung) dose limiting neurotoxicity. (remember crist, cns) paresthesia, loos of DTR, abdo pain, constip, motor weakness (withdraw) less myelosuppression with vincristine

vinblastine: less neuro. limiting effect is myelosuppression (remember blasts)

etoposide: (SCC of lung, lymphomas, testicular) alopecia, myelosuppression, nausea, vomiting

platinums

carboplatin: (ovarian, lung SCC). myelosuppressive. given as OPD, fewer other S/E than cisplatin.

cisplatin: (testes, lung, cervix, bladder, head, neck ovarian) IV hydration, nephrotoxic, ototoxic, peripheral neuropathy, hypomagnesemia, myelosuppression.

 

 

immunosuppressives

azathioprine: marrow suppression, liver toxicity, viral infection. metabolized to mercaptopurine, dose reduction if given with allopurinol.

increased risk of myelosuppression with low TPMT enzyme. thiopruine methyltransferase

mycophenolate mofetil: high rates of infection and leucopenia than with azathiprine, fewere rejections

cyclosporine (calcineurin inhib): nephrotoxic, not myelotoxic. used for prevention of graft rejection post marrow, kidney, pancreas, heart, lung, and GVH. also causes hirsutism

tacrolimus: more neurotoxicity and nephrotoxic than cyclosporine, cardiomyopathy, less hypertrichosis

sirolimus: hyperlipidemia

thalidomide: (myeloma) drowsiness, cosntipation, peripheral neuropathy, teratogen.

 

morphine

nausea, vomiting, cosntipation, drowsiness, impaired respiration, itch, miosis

ace inhibitors

hypotension, esp with diuretics , aortic stenosis

not with renal vascular disease

not with unstable heart failure

not in pregnancy

amiodarone

corneal microdeposits

UV sunscreen /photoxicity

thyroid abnormalities

pneumonitis

peripheral neuropathy

hepatoxic

TB drugs

avoid streptomycin in pregnancy

liver toxicity with isoniazid, rifampicin, pyrazinamide

renal toxicity with streptomycin, ethambutol

visual toxicity with ethambutol (loos of acuity, color blindness)

peripheral neuropathy with isonizid (give with pyridoxine)

rifampicin: 20-30% with intermittent use experience toxicity syndrome

including: influenza lie, abdomonial , respiratory, shock, renal failure, thrombocytoneic purprua,

rifampicin is an inducer, reduces contraceptive efficacy

drugs reducing contraceptive efficacy

rifampicin

agranulocytosis

clozapine

carbamazepine

colchicine

etoposide

ticlid

aplastic anemia

dry tap, hypocellular marrow, no splenomegaly, no reticulocytes,

ddx from other causes of panyctopenia

nb pure red cell aplasia=thymoma

causes:

65% idiopathic

dose related

alkylating

antimetab

benzene

chloramphenicol

inorganic arsenic

idiosyncratic

chloramphenicol

phenylbutazone

organic arsenicals

streptomycin

DDT

parathion

chlorpromazine

methylphenylethylhydantoin

viral

CMV, EBV, herpes , parvovirus B19

irradiation

fanconi syndrome

 

 

erythropoietin

rise in BP in 30%

rise in peripheral resistance

encephaolpathy, seizures, cortical blindness

not during pregnancy

NB teratogenesis not an issue until 4 postmenstrual weeks (2 postconceptual)

resistant to tertogens one week post implantation

vulnerable from about 4 postmonstrual to about 12 post menstrual

live viral vaccines(measles, mumps, rubella, polio, yellow fever)

lithium

ergot

warfarin: warfarin taken at time of conception unlikely to cause defects.

most common sx are nasal hypoplasia, stippled epiphyses.

also microcephaly, hydrocephaly, eyes, grwoth restrict, dev delay

risk greatest 6-9 postmenstrual week, 15-25%

phenytoin/trimethadione:

craniofacial, digital abn. in up to 30%. cleft lip, palate, hypertelorism, broad nasal bridge, epicanthal folds. hypoplasia of phalanges/nails

valproate: 1-2% spina bifida

amantadine

vidarabnine

methotrexate

abacavir

efavirenz

delavirdine

MARGINAL DURING PRGNANCY

gentamicin

TMP SMZ

AZT

OK DURING PREGNANCY

beta lactam

tegretol-carbamazepine-SIADH.

ABNORMAL FLUID, ELECTROLYTE, RENAL SCENARIOS

1. Low Urine Output/Acute renal failure

2. Addisonian crisis

3. Hyponatremia

4. SIADH

5. Hypo/Hyperkalemia

6. Edema

7. Hyper/hypocalcemia

8. Diabetes insipidus

9. diuretics

10. ACE inhibitors

11. renovascular disease

12. hypertension

13. complications of hemodialysis

14. renal transplant

15. nephritic syndrome

16. nephrotic syndrome

17. renal tubule acidoses

18. acid base

19. hematuria

20. hypoglycemia

urea and creatinine

urea: ( 7-18 mg/dL) (1.2-3.0 mmol/L)

rises in catabolism, after protein meal, steroids, tetracycline, GI bleed.

falls in liver failure, low protein intake, valproate

creatinine: (0.6-1.2 mg/dL) (53-106 micromole/L)

rises with muscle protein turnover, rhabdo, large muscle mass, red meat, cimetidine or trimethoprim

falls with low muscle mass

you can lose up to half your GFR and your creatinine may only rise slightly.

normal creatinine clearance in a male: 97-137 mL/min

normal creatinine clearance in a female: 88-128 mL/min

BUN/creatinine.

>20:1 prerenal,

>10:1 postrenal.

10:1 renal,

serum albumin

3.5-5.5 g/dL

 

PLASMA OSMOLARITY (275-295 mOsm/kg)

predicted osmolarity= [2(Na+)] + [(glucose)/(18)] + [(BUN)/(2.8)] + [(ETOH)/(4.6)]

 nb this is in American units.

Calcium: (8.4-10.2 mg/dL) 2.1-2.8 mmol/L

K+ (3.5-5.0 mEq/L)

Mg. (1.5-2.0 mEq/L)

PO4 (3.0-4.5 mg/dL)

uric acid (3.0-8.2 mg/dL)

chloride 95-105 mEq/L

bicarbonate 22-28 mEq/L

ACID BASE

winters formula

expected correction in metabolic acidosis

PCO2= 1.5[HCO3]+ 8 (+/- 2).

expected correction in metabolic alkalosis

PCO2= 0.7[HCO3]+20 (+/-1.5)

URINE ANALYSIS

normal FE Na. <1% suggests prerenal. greater than 1% suggests renal or post.

urine sodium < 20 suggests prerenal, >40 suggests renal/post

urine:serum creatinine: >40:1 suggests prerenal, renal or postrenal suggests <20:1

URINE SEDIMENT

normal 24 hour urine protein: less than 150 mg/24 hours

pyuria in a man: >1-2 WBC/hpf with bacteriuria

pyuria in a woman: 2-5 WBC/hpf with bacteriuria

asymptomatic bacteruria: 10 to the 5th per mL of one organism.

granular casts: ATN.

ALSO IN ATN:

renal tubule cells,

renal tubule cell casts

muddy brown casts

albumin/RBC cast : glomerulonephritis, malignant hypertension

WBC cast: interstitial nephritis, pyelonephritis (look for eosinophils in interstitial nephritis, special stain)

clumped leukocytes with bacteria in fresh void clean specimen suggest UTI

crystals: calculi, sulfas, ethylene glycol, radiocontrast

ACUTE RENAL FAILURE

 

ACUTE ON CHRONIC RENAL FAILURE

look for reversible causes such as

1. volume contraction

2. volume overload

3. worsening hypertension or hypotension

4. nephrotoxic drugs

5 .infection

6. obstruction

combination of ACE inhibitor and diuretic

 

MANAGEMENT OF CHRONIC RENAL FAILURE

progession of renal failure likely with

1. UTI

2. PNA

3. dehydration

4.medications

5. poor BP control

Prevention of progression:

all patients should be on ACE I or ARB to combat hyperfiltration

a marker of progression is proteinuria

 

control the following

1. hypertension

2. hyperkalemia

3. bone disease

use phosphate binders.

4. anemia

need to correct so that LVH does not develop. use EPO 50 U/kg 3times per week

5. uremic symptoms, eg nausea not eating, pericarditis, pruritus, volume overload

Targets:

BP 130/80

salt restriction of <100 mmol/day

protein < 0.8g/kg/day

calories 35 kcal/kg/day

K+ restrict

 

 

 

HYPERKALEMIA

DECREASED EXCRETION

1. renal failure (commonest cause)

also renal causes include

a. sickle cell

b. SLE

c. postrenal transplant

d. obstructive uropathy

2. drugs:

a. ACE inhibitor plus K+sparing diuretic(amiloride, triamterene, spironolactone)

b. NSAIDS

c. cyclosporin

d. heparin

3. acidosis

4. aldosterone deficiency

5. Addisons

6. Gordon's syndrome(opposite of Bartters, renal retention of sodium, HTN, low renin/aldosterone, hyperkalemia, met acidosis)

INCREASED RELEASE FROM CELLS

1. acidosis

2. diabetic ketoacidosis

3. rhabdomyolysis/tissues/burns/acute vigorous exercise (alpha adrenergic)

4. tumor lysis

5. succinylcholine (worse w/denervation)

6. digoxin poisoning (nb digoxin poisoning is made worse by hypokalemia, but digoxin can cause hyperkalemia) If there is hyperkalemia and digoxin poisoning it means you need to use immune fab rx.

INCREASED LOAD

1. transfusion

2. potassium chloride

3. salt substitutes

SPURIOUS

1. leukemia

2. infectious mono

3. thrmobocytosis

4. familial pseudo hyperkalemia

5. hemolysis

6. fist clenching during phlebotomy

RARE CAUSES

1. type 4 renal tubule acidosis: hyporenic hypoaldosteronism

2. pseudohypoaldosteronism (AD,AR)

3. hyperkalemic periodic paralysis

MANAGEMENT OF HYPERKALEMIA

nb may be asymptomatic or

weakness

paralysis

diarrhea

colic

vomiting

 

hyperkalemia is defined as anything greater than 5.5

treat anything greater than 7.0 immediately

ecg shows

at 6.5-7.5 peaked t, short qt, prolonged pr

at 7.5-8.0 wide qrs, flat p

greater than 8.0 sine wave, v fib, heart block

it is as if someone pulls the trace as if pulling a string

cells hyperpolarize, cardiac muscle is less excitable, results in hypotension and bradycardia, eventually asystole

take these measures immediately:

put the patient on a monitor. especially if on digoxin bc these measures can cause hypokalemia which worsens digoxin.

-give calcium 10 mL 10% calcium gluconate to protect heart in presence of ecg changes , calcium stabilizes cells

in children give 0.5 mL/kg of 10% solution

DO NOT GIVE CALCIUM IF ON DIGOXIN.

-drive potassium into cells with 10 units of fast acting insulin and 50 mL of 50% glucose,

be sure to check the K and glucose regularly after

-correct acidosis less than 6.9 with NaHCO3 1.26%.

nb do not use 8.4 % as it causes volume expansion

-if necessary give salbutamol 0.5 mg in 100 mL of 5% glucose (nb may cause tremor)

-maintain diuresis with furosemide 20-40 mg push

obtain the following:

ECG, U/E, Ca mg, po4, ABG, urine,

later deplete K with polystyrene sulphonate resin (kayexelate) 15 g orally three times daily with laxative

one gram binds 1 mEq of K+ , use w sorbitol b/c constipating, can exacerbate CHF

resins may cause either volume expansion if they contain sodium or hypercalcemia if they have calcium.

nb gastric aspiration removes potassium and leads to alkalosis

hemodialysis or peritoneal dialysis

 

HYPONATREMIA

causes

basically hyponatremia is due to either

1. too much water

2. too little salt

it may be factitious due to too much glucose, protein, or lipids in this case it does not need correction.

MANAGEMENT

you need to assess the volume status.

if it is low then it is probably due to some loss of salt from the gut or kidney

if it is high then it is probably because there is too much water

if it is normal then it gets tricky and you have to investigate to exclude:

1. Addisons

2. hypothyroid

3. SIADH

4. drug induced

5. K+ and Mg 2+ depletion causing ADH release

in a hyponatremic patient, look at the urine sodium, whether there is volume depletion, then look at the plasma osmolarity.

if the urine sodium is high, eg greater than 20 mmol with volume depletion this suggests salt wasting.

if the urine sodium is high, and there is no volume depletion this suggests that there is too much ADH. if the plasma osmolarity is lower than it should be, this suggests SIADH. if the plasma osmolarity is high this suggests that the ADH is appropriate and aldosterone is not working normally or there is a problem with the kidney.

if the urine sodium is low, eg, less than 10 then the patient is either conserving salt but there is a loss somewhere, or there is a diuresis, or the kidney is banjaxed.

assess volume status

1. JVP: can detect raised volume but not low volume . if the volume is low the JVP is less than 5 cm H2) and is seen only with patient flat or head down.

2. CVP after fluid challenge

3. serial weights

4. postural change in BP nb normally BP RISES when you stand up due to venoconstriction to maintain cerebral perfusion.

5. chest x ray

 

take the following measures:

1. restrict fluids

2. correct sodium slowly, never more than 70 mmol/hr, beware central pontine myelinolysis

3. avoid hypertonic saline in patients with heart failure use mannitol instead

4. review diuretics

5. only use hypertonic saline if seizure or coma

6. correct magnesium or potassium

if the patient is hypovolemic:

give oral rehydration

increase salt intake with slow sodium 60-80 mmol

if the patient is vomiting or has severe volume depletion give NS with potassium

THE TRICKY ONE: a NORMAL ECV (EUVOLEMIC HYPONATREMIA)

ADH.

too much release of ADH

1. SIADH

2. deficiency of ACTH

3. deficiency of gluoccorticoid (addison)

4. hypothyroidism

5. K+ depletion , magnesium depletion: can be causes of diuretic associated hyponatremia

6. unmeasured osmotic substances stimulating release

a. glucose

b. chronic alcohol abuse lowers set point for ADH release.

c. mannitol

d. sick cell syndrome (intracellular stuff)

e. increased ADH in response to stress like surgery

increased sensitivity

1. chlorpropamide

2. tollbutamide

something that acts like ADH

1. oxytocin

2. AVP

psychiatric

1. psychogenic polydipsia

2. antidepressants

HYPONATREMIA WITH DECREASED ECV (HYPOVOLEMIC HYPONATREMIA)

loss of sodium from either

gut

vomiting

diarrhea

hemorrhage

kidney

DIABETES!!!!!!

osmotic diuresis with glucose or uremia

excessive diuresis

ACTH deficiency

tubulo-interstitial renal dz

unilateral renal artery stenosis

recovery of ATN

HYPONATREMIA WITH INCREASED ECV (HYPERVOLEMIC HYPONATREMIA)

failures

1. heart failure

2. liver failure

3. oliguric renal failure

4. hypoalbuminemia (nephrotic syndrome)

nb these can all be made worse with loop diuretics or thiazides

given too much fluid

1. post surgical

2. pushing fluids in chronic renal failure

HYPOKALEMIA

defined as K+ less than 3.5

actively intervene at K+ of 2.9 especially if at risk of afib or cardiomyopathy due to risk of arrhythmias

if less than 2.5 replace iv

never more than 40/Liter

always monitor for dysrhythmias

replace at 20 mEq per hour raises 0.25 mEq/L

up to 10 mEq per hour peripheral line, up to 20 mEq per hour central line

oral replacement safer than iv

take the following measures:

-withdraw diuretics and laxatives

-oral supplements of potassium

-replace iv only if arrhythmia risk, DKA, muscle weakness

-correct hypomagnesemia

SYMPTOMS and COMPLICATIONS

weakness, cramps, hyporeflexia

ileus

dysrhythmia

hypotension, hypertension

worse digoxin

metabolic alkalosis

worse hepatic enceph

glucose intolerance

ECG: ST depression, prologned QT, U waves

worsen hyponatremia

atrial and ventricular ectopics

associated with interstitial renal disease

CAUSES

COMMONEST: Diuretics, hyperaldosteronism

1. INCREASED RENAL LOSS

a. due to loop diuretics, thiazides

b. renal tubule acidosis

c. renal tubule damage

d. acute leukemia

e. cytotoxic treatment

f. amphotericin

g. aminoglycosides

h. release of urinary tract obstruction

i. Bartters, Liddles, Gitelmans

Bartters: like loop diuretic, treat with amiloride or NSAID , raised renin, prostaglandin E, high urine K hypercalciuria, Mg wasting, normal bp, high aldosterone.

Gitelmans: like thiazide . no raised PGE, hypercalcemia. treat with K supplement, K sparing diuretic,

Liddles: low potassium, alkalosis, hypertension, low aldosterone. constitutive acitvation of amiloride sensitive sodium channel. cannot be treated with aldosterone antagonist. rx with amiloride.

 

2. EXOGENOUS:

Steroids (mineralocorticoid effect), licorice

3. HYPERALDOSTERONISM

a. liver failure

b. heart failure

c. nephrotic syndrome

d. Cushings

e. Conn’s

f. ACTH tumor

4. REDISTRIBUTION

a. nebulizers (Beta adrenergic stim)

b. acute MI

c. alkalosis

d. insulin treatment eg rx of DKA

e. B12 deficiency correction

f. hypokalemic periodic paralysis

5. GI LOSS

a. vomiting

b. diarrhea

c. laxatives

d. villous adenoma

e. ileostomy

f. fistula

g. ileus/intestinal obstruction

 

 

HYPERNATREMIA

usually means there is a water deficit

causes:

1. impaired thirst or consciousness

2. diabetes insipidus (nephrogenic or central), lack of response to AVP if nephrogenic

3. osmotic diuresis DKA

4. insensible losses

5. excessive use of Na fluids.

treatment:

withdraw nephrogenic drugs.

avoid over-rapid correction resulting in cerebral edema

use NS only if Na is greater than 170

correct over 48 hours

use 0.45% NS in HONK

large volumes required in DI

if volume depleted sodium deficit may exist.

HYPOMAGNESEMIA

normal range 0.7-1.1.

hypocalcemia usually accompanies

makes hypokalemia refractory

treatment: withdraw diuretics, laxatives, give 50 mmol in 1 liter 5% dextrose 12-24 hours.

causes:

deficient intake

malabsorption: NG suction, laxatives, fistulae, diarrhea

acute pancreatitis

diuretics

laxatives

alcohol

DKA

hyperaldosteronism

hypercalciuria

vit D 3 defic

nephrotoxins

HYPERMAGNESEMIA

causes:

acute or chronic renal failure given mg2+

adrenal insufficiency

antacids

dialysis with high Mg2+ dialysate

 

treatment:

same as for hyperkalemia:

calcium gluconate 10mL of 10% with dextrose 50% 50 mL and insulin 10 units.

may require dialysis

 

POSTURAL CHANGES....

normally BP rises with standing to maintain cerebral perfusion due to venoconstriction

a fall in BP with standing is abnormal , eg greater than 20 mm Hg fall is abnormal

a pulse difference of more than 30 beats per minute from lying to standing is significant

postural testing is used to distinguish between two types of hyperaldosteronism due to hyperplasia or adenoma

if hyperadlosteronism is due to adenoma, the blood pressure RISES between 0900 supine and 1300 erect)

if hyperaldosteronism is due to hyperplasia, the blood pressure FALLS between 0900 supine and 1300 erect.

CAUSES of POSTURAL HYPOTENSION

1. hypovolemia

2. autonomic failure

a. diabetes

b. systemic amyloidosis

c. ShyDrager

3. Drugs: loss of vasoconstriction

a. nitrates

b. calcium channel blockade

c. alpha blockers

4. Drugs: autonomic blockade

ganglion block

tricyclics

5. cardiovascular deconditioning with bed rest.

DIURETICS

diuresis can cause volume depletion and prerenal failure

diuretics can cause allergic tubulinterstital nephritis

thiazides

thiazides can increase urea

thiazides can directly cause a GFR drop

thiazides may be ineffective with a low GFR, except for metoloazone

thiazides reduce calcium excretion and raise CA2+, this is useful in hypercalciuria

loop diuretics

Furosemide causes

1. hypocalcemia

2. urate retention (gout)

3. hypokalemia

4. hypomagnesemia

5. impaired glucose tolerance

6. allergic tubulointerstitial nephritis

7. myalgia

8. ototoxicity

9. interference with lithium excretion

spironolactone

treatment of choice for cirrhosis/edema/ascites

long term use assoc with tumors

treatment of primary hyperaldosteronism due to hyperplasia

for use in renal artery stenosis

used in heart failure 25 mg/day

for use in treatment of hirsutism

gynecomastia

potassium sparing therefore avoid potassium

ACE INHIBITORS

problems:

avoid in unilateral renal artery stenosis as well as bilateral

avoid in unidagnosed or clinically silent peripheral vascular disease/atherosclerosis for this reason.

first dose hypotension

cough

angioedema

indications:

heart failure.

diabetic nephropathy

 

EDEMA

abnormal sodium chloride retention

expansion of ECV by 2 liters (15%)

Causes:

1. heart failure

2. hypoalbuminemia

3. hepatic cirrhosis

4. sodium retention

a. mineralocorticoids

b. licorice

c. estrogens (eg PMS weight gain)

d. decreased GFR with renal failure

e. NSAIDS combined with heart failure, cirrhosis, renal artery stenosis

5. initiation of insulin treatment

6. refeeding after malnutrition

7. calcium channel blockers nifedipine

8. increased capillary permeability

a. complement deficiency

b. interleukin 2 in chemorx

c. ovarian hyperstimulation

9. idiopathic edema of women

10. local edema:

a. post thrombosis

b. immobility

c. SVC obstruction

LYMPHEDEMA

 

LOW URINE OUTPUT

INVESTIGATIONS WITH LOW URINE OUTPUT:

screen with renal ultrasound for obstruction

U/E

urine sodium and osmolarity

plasma osmolarity

 

ACUTE URINARY RETENTION

distressed patient

abdominal pain

palpable bladder

risks:

immobility, supine, lack of privacy, anesthesia resulting in bladder dysfunction, pelvic operations, abdominal wounds preventing voiding due to pain., male pt, prostatic hypertrophy

diagnosis:

abdominial mass dull to percussion

confirm with ultrasound

confirm with urinary catheter

management:

analgesia

privacy/commode/bottle

catheterisation

 

 

SIADH (hyponatremia)

patient is conserving water inappropiately for the plasma osmolarity

the plasma osmolarity is too LOW

the urine osmolarity is too HIGH

patient may have a LOW sodium or LOW chloride

urea is NOT increased

treatment

1. water restriction

2. determination of cause of ADH secretion eg neoplasm, etc.

if prolonged: demeclocycline to promote DI

if emergency (seizures): hypertonic saline with loop diuretic, slow correction of Na.

 

CAUSES of SIADH

1. LUNG

a. oat cell lung cancer

b. pneumonia/lungabscess

c. increased PEEP

2. CNS

a. CNS trauma

b. stroke

3. other

a. pancreatic cancer

b. duodenal cancer

c. general anesthesia

d. idiopathic

e. postoperative

f. morphine

ADDISONIAN CRISIS

acute adrenal insufficiency

signs:

tachycardia, hypotension, abdominal pain

fever

diarrhea

nausea

vomiting

lethargy

REFRACTORY TO IV FLUIDS AND PRESSORS

LOW sodium

HIGH K+

treatment:

IV Fluid

D5 NS

hydrocortisone IV

fludrocortisone PO

causes:

postoperative

inadequate steroids in a patient given chronic steroids

DIABETES INSIPIDUS

large urine outputs

large intake of fluid

either impaired ADH release (central):

a. head trauma

b. intracranial problem

or kidney unresponsive to ADH (nephrogenic)

a. renal disease

b. lithium

c. U/E problem

treatment:

vasopressin.

fluids

CONN’S

Primary hyperaldosteronism

less than 1% of all HTN

hypokalemia

hypertension

20-40% have K+ of 3.5-4.2

features:

weakness, nocturia, tetany

severe effects of hypertension.

labs:

urine potassium greater than 30 in face of low serum potassium

raised aldosterone:renin ratio

plasma aldosterone not suppressed with 0.9% saline or fludrocortisone

low plasma renin activity

 

 

Adenoma vs. hyperplasia

ADENOMA: very small, common in young females, postural changes rise, raised 18-OH cortisol

remove surgically, 70% respond with BP drop,

HYPERPLASIA: rarely before 40, males. postural changes fall, treated medically with spironolactone (risk of nausea, rashes, gynecomastia, tumor development), or with amioloride, or with calcium channel blockade for hypertension.

 

SECONDARY HYPERALDOSTERONISM

excess renin stimulation of adrenal cortex zona glomerulosa

causes:

1. renal artery stenosis

2. accelerated hypertension

3. congestive heart failure

4. cirrhosis

treatment:

ACE inhibitors

spironolactone

RENAL VASCULAR DISEASE

unilateral renal artery stenosis

a. fibromuscular hypoplasia in young women

b. elderly due to atheroma

ischemic kidney shows

1. concentrated urine

2. low sodium

3. decreased clearance of inulin, PAH, creatinine

investigations

radionuclide: fall in isotope uptake post dose of captopril

arteriography

treatment:

1. angioplasty,

2. stent

3. vascular reconstruction

4. nephrectomy

AVOID ACE inhibitors as can cause acute renal failure

AVOID NSAIDS

unilateral atrophic pyelonpehritis (AKA unilateral reflux nephropathy)

indication for nephrectomy if kidney inadequate fxn and young pt.

ACUTE INTERSTITIAL NEPHRITIS

acute tubulointerstitial nephritis

causes:

hypersensitivity reaction to drugs.

penicillin

NSAIDS

cimetidine

furosemide

thiazides

allopurinol

treatment: removal of drug, prednisolone

CHRONIC INTERSTITIAL NEPHRITIS

common:

1. reflux nephropathy

2. NSAIDS

3. sickle cell

4. DM

5. cadmium/lead

Rare:

1. Alport syndrome

2. Balkan nephropathy

3. irradiation

4. Sjogren

5. hyperuricemic nephropathy

Papillary necrosis vs. reflux nephropathy

papillary necrosis

1. bilateral

2. no loss of cortex

reflux nephropathy

1. can be unilateral

2. loss of cortex over clubbed calyces

REFLUX NEPHROPATHY

chronic pyelonephritis/atrophic pyelonephritis

 

 

HEMODIALYSIS

 

Continuous Renal Replacement Therapy (CRRT)

Continuous Veno-Venous Hemodialysis (CVVHD)

Continuous Veno-Venous Hemofiltration (CVVHF)

Continuous Ambulatory Peritoneal Dialysis (CAPD)

ABSOLUTE INDICATIONS: AEIOU

A: Acidosis (especially if severe (pH < 7.2 and refractory to HCO₃ or unable to give HCO₃ due to volume overload). bicarbonate less than 12. acidosis of chronic renal failure is usually 12-15, not severe because it is failure of excretion of daily load, not overproduction.

E : Electrolytes especially potassium > 6.5-7 mmol/L or with ECG changes. Temporize with calcium, D₅₀ + insulin, HCO₃, beta-agonist nebulizers, and kayexalate.

I: Intoxication: lithium or ethylene glycol.

O: Overload: volume overload causing pulmonary edema. Temporize with nitrates and large doses of furosemide (160–200 mg IV). Unresponsiveness to diuretics indicates that dialysis should be started emergently in pt w ESRD.

U: Uremia confusion, pericarditis, seizures, platelet dysfunction with severe bleeding, and intractable nausea/vomiting.

uremia: deterioration of renal function, GFR <20% with symptoms

chronic renal insufficiency: serum creatinine 1.5-3.0 mg/dL (133-265 micromolar)

chronic renal failure: serum creatinine >3.0 mg/dL

dialysis if (7,12,20,500) KHUC

K>7 mmol

HCO3<12 mmol

Urea>20 mmol (greater than 100 mg/dL)

Creatinine> 500 micromol (greater than 10 mg/dL)

 

 

 

RENAL DISEASE WITH PROTEINURIA

NEPHROTIC SYNDROME

components:

1. low albumin,

2. high lipid,

3. edema,

4. high urine protein

complications:

1. hypercoag

2. infection

3. calcium, bone disease

4. progressive renal disease

 

nb selective protein leak: minimal change, diabetes, amyloidosis

non selective: cresecentic diffuse proliferative

nb no renal bx in young child with selective leak, no hematuria, and no htn, not in DM, and not in penicillamine

DVT especially common in membranous glomerulonephritis

causes

primary nephrotic syndrome (all glomerular diz can cause)

1. minimal change

2. focal segmental glomerulosclerosis

3. membranous nephropathy

4. membranous progressive glomerulonephritis

5. Ig A nephropathy (macroscopic hematuria, also a cause of nephritic syndrome)

secondary nephrotic syndrome

1. diabetes mellitus

2. SLE

3. amyloid

4. light chain nephropathy

5. NSAIDS

6. drugs

7. HIV

8. lymphoma

treatment

1. ACE I

2. BP control

3. diuretics

4. salt restriction

5. Steroids in SLE, minimal change

6. plus or minue thromboembolism prophylaxis

GLOMERULAR DISEASES

granular pattern on IF (45%)suggests immune complexes : this indicates:

a. IgA,

b. post strep

c. lupus

d. membranoproliferative (mesangiocapillary)

linear pattern on IF suggests anti-basement membrane (goodpastures) (5%)

pauci-immune: suggests ANCA, wegeners, PAN.

 

NEPHRITIC SYNDROME

acute hematuria, acute renal failure, hypertension, edema, oliguria with an active urine sediment.

rapidly progressive glomerulonephritis is SUBACUTE, not acute. it occurs over weeks to months

 

 

 

 

 

MYELOMA KIDNEY DISEASE

urine light chains not detected by dispticks, only accounted for in 24 hour urine collection.

anemia severe for renal insufficiency: marrow suppression and plasma cell infiltrate

low anion gap

RENAL TRANSPLANT

while waiting: blood transfusions from donor good, as opposed to while waiting for marrow transplant

avoid other transfusions as it causes HLA sensitization

best survivial:

living HLA DR>B>A matched

ABO matched

cadaveric

drug side effects:

hyperkalemia, RTA, HUS, tremor, hirsutism, gum hypertrophy, hypercholesterolemia

drugs:

steroids

cyclosporine

FK506(tacrolimus)

azathioprine

mycofenolate mofetil

complications:

opportunistic infxn. CMV PCP

CAD

HTN

lymphoma

skin cancer

steroid complications

 

 

RENAL TUBULE ACIDOSES

Renal tubule acidosis is a normal anion gap condition caused by a failure of acid secretion (distal)or a failure of bicarbonate reabsorption(proximal). It can also be caused by aldosterone deficiency, type IV.

 

Proximal renal tubule acidosis is a consequence of impaired reabsorption of bicarbonate in the presence of intact acid excretion mechanisms and an ability to excrete normal amounts of NH4+ (intact ammonium trap). If plasma bicarbonate is increased, the urine will temporarily become alkaline due to the increased excretion of bicarbonate. Proximal tubule acidosis is associated with the Fanconi syndrome, in which proximal solute absorption is impaired for a range of solutes. A distinctive feature is hypokalemia. Note that hypokalemia is normally associated with alkalosis. The essential diagnostic feature of PTA is the diminished renal threshold for bicarbonate. Proximal renal tubule acidosis (type2) is a failure of the proximal tubule to reabsorb bicarbonate. The increase in urinary bicarbonate indicates that bicarbonate reabsorption is limited. In normal individuals, the Tm for bicarbonate occurs at 26 mEq/L if NaHCO3 infusion is used to increase HCO3. the calculation of the fractional excretion of bicarbonate allows discrimination of this disorder from distal tubule acidosis. The fractional excretion is calculated by comparing the excretion of HCO3 to the filtration of HCO3, with knowledge of the creatinine clearance as a marker for the GFR

It should be clear that in a normal individual, the urinary bicarbonate concentration is very low, so relative to the quantity filtered, fractional excretion of bicarbonate is miniscule. However, if an individual has proximal tubule acidosis, the fractional excretion of HCO3 can increase to 15%.Many factors may result in impaired proximal reabsorption of bicarbonate, such as the metabolic acidosis associated with hyperparathyroidism, the metabolic acidosis associated with acetazolamide use, and the deficiency of proximal tubule function in Fanconi anemia. The most common cause in adults is probably multiple myeloma, resulting from toxicity of filtered light chains. The diagnosis is based on the observation of a normal anion gap acidosis with slightly reduced bicarbonate levels, and the presence of hypokalemia (acidosis with hypokalemia is unusual and occurs because bicarbonate results in negative lumen in collecting duct favoring K+ excretion, with normal acidification). Paradoxically, bicarbonate levels are higher with this disorder than with distal tubule acidosis. The treatment is bicarbonate infusion, which may need to be quite high to restore bicarbonate levels because of the defect in reabsorption. Oral bicarbonate therapy may create sufficient CO2 gas in the stomach through the combination with stomach H+ to cause significant gastrointestinal distress.

Distal tubule acidosis is characterized by an inability to excrete acid in the distal tubule in the presence of acidemia, thus urinary pH is not usually less than 5.5. Sjogren's syndrome may be associated with distal renal tubule acidosis (type1) in some patients. Because the onset of renal tubule acidosis in these patients precedes the onset of other features of the disease, patients with renal tubule acidosis type 1 should be monitored for the development of other symptoms

. Aldosterone deficiency, or renal tubule acidosis type 4, is a metabolic acidosis that develops as a consequence of failure of aldosterone to stimulate potassium excretion and H+ excretion. Because the disorder does not substantially interfere with bicarbonate reabsorption proximally, the level of bicarbonate in the urine would not be expected to rise. This is because serum bicarbonate buffers the excess H+, which reduces serum bicarbonate and hence reduces the filtered load of HCO3, which is why the deficiency in distal bicarbonate reabsorption has little effect. The disorder is an anion gap metabolic acidosis, characterized by hyperkalemia and lack of NH4+ excretion. Correction of hypokalemia is essential.

HEMATURIA

(renal cell ca)

(transitional cell ca)

(stone) (see page on renal/loin pain)

(nephritic syndrome) (see page on nephritic syndrome)

(UTI)

painless hematuria suggests tumor

flank pain can occur with renal tumor

bladder tumor may result in UTI, strangury, or urine retention

painful hematuria suggests stone or infection

clots may cause ureteric obstruction

renal infarct due to embolus can cause hematuria: ask about rheumatic haert disease, anticoagulants, and afib

blood in the entire stream suggests an upper tract source

blood at the beginning or end suggests lower source eg urethra

malignancy is a prime concern

risks: males over 50, smoking, rubber, cable, dye, printing industries

exam:

signs of anemia

hypertension

polycythemia (EPO due to renal cell ca)

mass in abdomen/loin

inspect urethra

examine testicles: right sided varicocele, right renal vein

prostate, vaginal exams

investigations:

MSU,

microscopy

cytology

ultrasound

cystourethroscopy

RENAL CELL CA.

primarily a tumor of adults

aka hypernephroma, Grawitz tumor

"obliteration /distortion of the calyceal system"

Ultrasound distinguishes cyst(usu benign) from solid

CT scan to determine extent of invasion

invasion is to:

1. renal vein

2. IVC

3. perinephric

4. lymph nodes

5. liver mets

arteriography only if partial nephrectomy an option to determine anatomy

FBC for anemia

LFTS if abnormal suggests poorer prognosis even if no mets

CXR for pulm mets

Tumor Staging

T1: less than 7 cm limited to kidney

T2 greater than 7 cm limited to kidney

T3 veins, adrenal, perinpehric not beyond Gerota fascia

T3a adrenal perinephric not beyond Gerotas

T3b grossly into IVC or renal vein

T4 beyond Gerotas

Treatment:

radical nephrectomy: removal of kidney, ureter, adrenal, Gerota's fascia

transperitoneal, transthoracic, or loin.

removal of pulm mets at same time

40% 5 year survival

metastatic dz/adjuvant: interferons/interleukins being evaluated

 

 

 

 

TRANSITIONAL CELL CA

four times as common as renal cell ca

in the bladder, calyx, pelvis of kidney, ureters

92% of bladder tumors are transitional cell

the rest are squamous (7%) or adenoca (1%) from remnants of the embroyological urachus

accounts for only 7% of renal tumors

tumors of ureter and renal pelvis account for only 2-4% of TCCa

if TCC of pelvis or ureter then 30-50% chance of tumor of bladder in future

if TCC of bladder then only 2-3% chance of upper tract tumor in future

"filling defect in collecting system"

IVU, ultrasound, uretoscopy, urine cytology

nephroureterectomy, partial cystectomy

annual cystoscopic followup

Superficial Tumors

Ta non invasive papillary

Tis carcinoma in situ

T1 subepithelial connective tissue

treated with transurethral resection, flex cystoscopy every 3/12 then 6/12 then annual

higher risk with smoker, large tumor, dysplasia or CIS on bx, high grade superficial tumors

intravesical chemorx. : BCG, adriamycin, mitomycin C etc

5 yr survival 75%

Invasive Tumors

T2: muscle

T3: perivesical

treated with radical radiotherapy or radical cystectomy

5 yr survival is 35-40%

radiation risks;

cystitis,

proctitis

salvage cystectomy difficult

Radical cystectomy:

requires ileal conduit or bladder reconstruction or catherizable diversion

metastatic tumors

palliative chemotherapy, palliative radiotherapy, both

survival median 1 yr.

SQUAMOUS CELL CA

complicates bladder schistosomiasis

risk of long term cathetierization

treated as for TCC except if distal urethra: treated as penile carcinoma and amputation of penis and dissection of inguinal lymph nodes.

NEPHROBLASTOMA

infancy/childhood.

embryonal renal tissue

abdominal mass

before age 3

resection, radio, chemo even when mets excellent chances of cure

Hypoglycemia

EXPLAIN: Causes

Ex Exogenous Insulin, drugs, aminoglutethemide, 4-quinolones, pentamidine, quinine sulfate

P Pituitary insufficiency

L Liver failure

A Addison's

I Insulinoma (c peptide present, does not diminish or suppress with exogenous insulin administration)

N Neoplasia: retroperitoneal fibrosarcomas, hemangiopericytomas

 

RX: give 50 mL 50% dextrose iv fast, followed by saline flush (vein injury)

if fails try glucagon 1-2 mg im

give sugary drinks

glucose <2.5 mmol/L

autonomic: sweating hunger tremor

neuroglycopenic: drowsy personality change, seizures , loss of consciousness

Investigations:

fingerprick glucose

exclude liver failure

exclude malaria

perform 72 hour fast

measure insulin, c peptide, ketones, glucose

 

Patterns:

hypoglycemia with high insulin and no ketones=> insulinoma, exogenous insulin,

hypoglycemia, with low insulin and no ketones=> non pancreatic neoplasm, anti insulin antibodies

hypoglycemia with low insulin and high ketones=> alcohol, pituitary, adrenal failure

CALCIUM

hypocalcemia/hypercalcemia

hyperparathyroidism/hypo

osteoporosis

Paget's

HYPERPARATHYROIDISM

(parathyroid adenoma)

(parathyroid carcinoma)

(MEN syndrome)

(Secondary hyperparathyroidism/renal failure)

(tertiary hyperparathyroidism)

HYPERCALCEMIA

P(parathyroid hormone)

A(addisons)

M(milk alkali)

P(Pagets disease)

S (sarcoidosis)

C (Cancer /bony metastases)

H (hyperthyroidism)

M(multiple myeloma)

I (immobilization)

D(hypervitamin D

T(thiazides)

mnemonics:

CHIMPANZEES

PAM P SCHMIDT

HORMONES

PTH puts PO4 in the urine, increases Ca 2+

Vit D absorbs Calcium

LAB VALUES

Calcium: (8.4-10.2 mg/dL) 2.25-2.6 mmol/L2.1-2.8 mmol/L

correct for plasma proteins

if hypoalbuminemic:

[[4-(albumin)]*0.8], add this to the calcium level.

or add or subtract 0.02 mmol/Liter for every gram per liter of albumin above or below 40 gram per liter.

e.g if albumin falls then calcium also falls,but not the ionized part.

alkalosis causes a fall in ionized calcium. A rise in pH by 0.1 causes a fall in ionized calcium by 3-8%.

Mg. (1.5-2.0 mEq/L)

PO4 (3.0-4.5 mg/dL)

uric acid (3.0-8.2 mg/dL)

PTH level 230-630 pg/mL

VIT D

ALKALINE PHOSPHATASE

raised in osteomalacia and Pagets, normal in osteoporosis and hypo/hyperparathyroid

SERUM PHOSPHATE

high in hypoparathyroidism, low in primary hyperparathyroid, may be low in osteomalacia, normal otherwise

SERUM CALCIUM

low in hypoparathyroidism, low or normal in secondary hyperparathyroid and osteomalacia

high in primary hyperparathyroid

chloride 95-105 mEq/L

bicarbonate 22-28 mEq/L

nb calcium can cause tissue necrosis if the IV tissues.

EMERGENCY MANAGEMENTof HYPERCALCEMIA

treat the following.

1. calcium above 12 mg/dL(or above 3.5 mmol/L)

2. symptomatic pt.

3. renal failure

4. pt who is NPO

take the following measures:

1. correct dehydration with NS, many liters may be required eg 4-6 liters

2. correct concurrent hypkalemia or hypomagnesemia

3. furosemide 40 mg but may worsen dehydration

4. if refractory, consider

a. pamidronate 15-60 mg ivi in NS or D5W over 2-8 hours

b. hydrocortisone 25-100 mg iv q6h

c. calcitonin 0.5-4 Units/kg iv over 24 hours (short action)

NB

a. avoid thiazides as they raise Calcium

b. oral phosphate causes diarrhea

c. IV phosphate rapidly lowers Ca but is dangerous and is avoided.

 

 

 HYPERCALCEMIA

P(parathyroid hormone)

A(addisons)

M(milk alkali)

P(Pagets disease)

S (sarcoidosis)

C (Cancer /bony metastases)

H (hyperthyroidism)

M(multiple myeloma)

I (immobilization)

D(hypervitamin D

T(thiazides)

 

other causes of hypercalcemia:

TB, lymphoma, chronic lithium, PTH related protein (paraneoplastic)

familial hypocalciuric hypercalcemia: autosomal dominant: increased reabsorption despite hypercalcemia.

see aafp review at http://www.aafp.org/afp/20030501/1959.html

presentation of hyperparathyroidism /hypercalcemia

(Stones, bones, abdominal groans, psychic moans)

stones

ureteric calculi (2-5%)

renal calcification

corneal calcification

bones

bone pain

deformity

only 5-10% have bony lesions when sought eg brown tumor

pathological fractures

muscular weakness

abdominal groans

anorexia

intestinal atony

polyuria

constipation

peptic ulcer

acute and chronic pancreatitis

psychic moans

psychiatric disorders

other important findings.

nb. one third of patients with hypercalcemia develop hypokalemia

ecg: ST depression, widened T waves, short QT, heart blocks

levels above 20 mg/dL: cardiac arrest.

 

mild asx hypercalcemia 1/1000 of popn

commonest cause primary hyperparathyroidism

second most common neoplasia resulting in hypercalcemia:

metastatic. then primary tumors.

bronchus, breast, myeloma, esophagus, thyroid, prostate, lymphoma, renal cell

severe hypercalcemia> 3 mmol/L

malignant disease, hyperparathyroid, vit D, renal failure

investigation

fasting calcium and phosphate

PTH

mild hyperchloremic acidosis.

U/E to assess GFR/creatinine

If PTH is low, then get:

thyroid function

cortisol/synacthen

ACE for sarcoid

hydrocortisone 40 mg tid 10 days to suppress sarcoid, vit D related, some neoplasia

parathyroid imaging if prior surgery: ultrasound, CT.MRI, radiisotope

 

 

 

 

 

PRIMARY HYPERPARATHYROIDISM

excess PTH, high serum calcium, high urine calcium, low PO4, alk phos is normal, 33 to 1 ratio of chloride to phosphate.

commonest cause of hypecalcemia (90%)

80% parathyroid adenoma

15-20% hyperplasia

1% carcinoma (NB, usually palpable, other causes not usually palpable parathyroid). HCG tumor marker.

MEN syndromes (I and IIa)

 

Management

Medical: take fluids, exercise, avoid calcium and vit D

Surgical:

indications for surgery

1. renal stones/impaired renal function

2. bony involvement or changes in cortical density

3. marked hypercalcemia greater than 3 mmol

4. young patient less than 50

5. previous episode of severe acute hypercalcemia

controversial
young patients with mild hypercalcemia, reduced bone density, or hypercalciuria

surgical complications:

bleeding

recurrent laryngeal nerve

postoperative complications:

hypocalcemia. “hungry bone syndrome” esp with severe bone dz

manage: alfacalcidiol. (vit D), monitor calcium, replete if necessary.

surgical management of HYPERPTH

hyperplasia: remove from neck, 30 mg in forearm

adenoma: remove, bx

carcinoma: remove, ipsi thyroid, all enlarged lymph nodes

 

SECONDARY HYPERPARATHYROIDISM

either due to renal failure or vit D deficiency, response to hypocalcemia

calcium wasting, elevated PTH secondary to this, low/normal calcium levels, alk phos is normal

management renal transplant

TERTIARY:

unresponsive PTH to negative feedback of elevated calcium

 

MILK ALKALI SYNDROME

triad:

1. metabolic alkalosis (Ingestion of oral alkali)

2. hypercalcemia

3. renal failure

 OSTEOPOROSIS

calcium, phosphate and alk phos are normal

fractures are only cause of symptoms

only 1/3 vertebral fx symptomatic

low bone mass

bone density below 2.5 stddev

at age 80 30% women, 15% men hip fx

vertebral crush fx: severe pain resolving over 6 weeks, requires bed rest with strong analgesia

colles fx

hip fx

DXA scan fx risk

treatment and prevention

risk factors

bisphosphonates

vit d

calcium

serms

PAGET DZ

bone remodelling

alkphos is raised, calcium raised if FX, phos normal

dx w. asx elev of alk phos, may be greater than 1000 U/L can be normal with nonostotic, may reduce with treatment, are a marker of relapse

xray: lytic lesions to sclerotic, dedifferentiation, mixed

bone scans cannot dx paget from sclerotic metastatic ca (breast/prostate)

bone pain, joint pain, deformity, nerve compression, path fx, hemodynamic derangement, osteogenic sarcoma 30 x risk

treatment: bisphosphonates. treat symptomatic minority and asx if risk of fx, surgery, nerve entrap, deafness.

eg tiludronate, risedronate

bisphosphonate resistance responds to changing drugs.

surgery may be required for deformity, pain, or neoplasia

RICKETS (children) OSTEOMALACIA (adults)

defects in vitamin D availability or metabolism

alk phos is raised,

calcium low or normal,

phosphate normal or reduced

Seconday hyperparthyroidism, elevated PTH

calcification and mineralization impaired

causes:

malabsorption due to celiac, cholestasis, resection, low intake

lack of sun

renal disease due to impaired hydroxylation, dialysis, tubular disorders loss of phosphate,

multiple myeloma, congenital deficiencies in 1 alpha hydroxylase, receptor.

neoplasms

anticonvulsant drugs

symptoms:

bone, muscle pain, weakness,

proximal myopathy

craniotabes thin skull

groove in rib cage, harrisons sulcus

investigations:

alk phos (elevated also during growth)

iliac crest bx w/tetracycline label

treatment:

nutritional replacement 400-800 IU vit D

pharm doses 40000-10000 IU/day in cases of gastrectomy, liver dz, hypoparathyroid, malabsorption

 

 

 

HYPOCALCEMIA

symptoms:

paresthesias, DTRS, cramps, troussea, chvostek, tetany

worse with alkalosis

refractory CHF can cause calcium to fall

ECG shows prolonged QT

differential of tetany.

alkalosis:

hyperventilation

excess antacid

persistent vomiting

hypochloremic alkalosis (primary hyperaldosteronism)

hypocalcemia

EMERGENCY MANAGEMENT

with tetany: give 10 mL of 10% calcium gluconate over 10 minutes

then give 0.25-2 micrograms of alphacalcifidiol, (1 alpha)

if asx, then PO calcium gluconate 1 g q6h

monitor levels frequently

INVESTIGATION

U/E for renal disease

PTH levels (low if hypoparathyroid, high otherwise)

parathyroid antibodies (idiopathic hypoarathyroid)

25 hydroxy vit D level (vit D defic)

X ray: short 4th metacarpal

COMMON CAUSES:

renal failure,

postoperative after thyroid, parathyroid

acute pancreatitis

low plasma albumin, malnutrition, liver disease.

blood transfusion w/citrated blood.

causes:

1. shock

2. sepsis

3. renal failure

4. pancreatitis

5. cimetidine, calcitonin, bisphosphonates

6. hypoparathyroidism

a. surgical

b. DiGeorge: intellectual, cataracts, calcif. basal ganglia, absent thymus.

c. idiopathic hyperparthyroidism, autoimmune, vitiligo, moniliasis, other autoimmune

d. severe hypomagnesemia

e. pseudohypoparathyroidism (PTH resistance)

7. phosphate overload

8. vitamin D deficiency

9. fat embolism

10. strychnine poisioning

11. hypomagnesemia

12. tetanus toxin

13. short bowel syndrome

14. diuretics (furosemide)

15. rhabdomyolysis

16. aminoglycosides

17. osteoblast metastasis

 

 

 

HYPOPHOSPHATEMIA

<0.4 mmol/L

maximum correction 9 mmol/12 hours

can result in hypocalcemia if corrected too rapidly, esp w/alkalosis

complications:

muscle weakness

less contractile cardiac

rhabdomyolysis

diaphragmatic weakness

left shift hemoglobin curve, more avid binding

hemolysis

confusion

hallucination

convulsions

hypophosphatemic rickets

low phosphate

high urine phosphate excretion

rachitic bone

unresponsive to vit D

x linked dominant

treatment is phosphate supplement with calcitriol vit d3.

HYPERPHOSPHATEMIA

chronic renal failure

raised calcium phosphate product

itching

precipitates

hyperparathyoidism

periarticular and vascular calcification

rx- gut phosphate binders

dialysis

Orthopedics and Rheumatology

bone pain.

nejm visual challenge- bone pain with abnormal cxr

visual stimulus- bamboo spine in anklyosing spondylitis. ankylosing spondylitis nejm


Infectious Disease
immunization schedule
tetanus
sepsis
neutropenic patient
HIV
pneumonia
Community Acquired Pneumonia
typical-strep, H flu, moraxella.
atypical-mycoplasma, chlamydia, legionella
others-pseudomonas, staph.

keywords-
strep-always commonest
H flu- etoh, diabetes, COPD
moraxella-copd
staph- IVDU, small infiltrates, necrotizing
klebsiella-etoh, upper lobes, currant jelly, necrotizing

aspiration

CT showing "ground glass opacities"

The finding of ground glass opacities in the lung on HRCT carries a long differential diagnosis. This includes UIP,DIP, and LIP, as well as diagnoses such as sarcoidosis, PCP and hypersensitivity pneumonitis. Ground glass opacities were initially felt to represent an active alveolitis, and therefore be a marker for treatable disease. Further radiologic-pathologic correlation, however, has shown that it can represent fibrosis at the intralobular, or microscopic level.

Hypersensitivity pneumonitis can be incited by a number of factors. Though the most common inciting antigens are the thremophilic Actinomycetes species, avian proteins (bird fanciers lung), drugs and chemicals are also commonly cited agents.

Clinically, the patient generally complains of dyspnea and cough, chills and fever 4-8 hours after exposure. Symptoms typically last from 12-60 hours but will often recur with repeated exposure. With chronic exposure, chronic cough, fatigue and anorexia can develop. Age at diagnosis, duration of antigen exposure and number of repeated exposures are the most important predictive values for long term sequelae.

Pathologically, a lymphocytic infiltrate with ill defined, non-caseating granulomas are seen microscopically. BAL results show increased cell counts, which are predominantly lymphocytic. While the process is predominantly interstitial, an active alveolar component is often present. As the process becomes more chronic, interstitial fibrosis is more commonly seen.

The CT and HRCT findings in hypersensitivity pneumonitis have been described. In general, acute, subacute and chronic stages have been described. The acute phase is characterized by wide-spread air space consolidation. The sub-acute stage is characterized by centrilobular nodules, with the development of predominantly upper lobe fibrosis in the chronic stage. A recent review of 17 patients with the diagnosis of hypersensitivity pneumonitis was performed. the most common CT finding was ground glass opacities in 11 of 14 patients. Six of 14 had evidence of centrilobular nodules. Unlike the chest radiograph findings which often suggest a lower zone predominance, the lungs appear diffusely involved on CT scan. HRCT is both more sensitive and specific than the plain radiograph in the diagnosis of hypersensitivity pneumonitis.

References:
Webb, WR,Muller NL, Naidich, DP High Resolution CT of the Lung
Philadelphia, Lippincott Raven 1996.

Hasleton, PS, Hypersensitivity Pneumonitis, in Spencers Pathology of the Lung,
New York, Mc Graw-Hill 1996.

Hansell, DM and Moskovic, E. High ResolutionComputed Tomography in Extrinsic
Allergic Alveolitis. Clin. Rad. (1991) 43, 8-12.

CT with ground glass opacities, honeycombing, reticular-nodular pattern, with clubbing and crepitations.

UIP is the most common chronic interstitial pneumonia. It has a variety of names, and is often referred to as idiopathic pulmonary fibrosis (IPF) or in Britain, cryptogenic fibrosing alveolitis(CFA). Pathologically, UIP shows evidence of alveolitis and increased cellularity of the alveolar wall. With progression, fibrosis and honeycombing occur. It is felt the pathologic changes of UIP probably represent an immunologic response to an inhaled or environmental pathogen. Following the initial insult to the endothelial and alveolar epithelial cells, recruitment of alveolar macrophages stimulate neutrophils and fibroblasts, with the progression from an alveolitis to interstitial fibrosis and organization. Proliferation of Type II pneumocytes occur, with deposition of collagen.

UIP occurs in 30-50/100,000 people. It has a slight male predominance, and usually presents in the 5th or 6th decade of life. While it is often idiopathic, approximately 30% have an underlying cause, usually a collagen vascular disorder. A number of other associations have been made, including chronic active hepatitis, primary biliary cirrhosis, ulcerative colitis, and celiac disease.

Patients generally present with dyspnea on exertion and cough. Fine late inspiratory crackles are characteristic on physical exam, and many patients will develop clubbing.

Radiographically, the plain film will show reticulonodular opacities and 25-60% will show decreased volumes. HRCT will show evidence of intralobular and interlobular thickening. Irregular interfaces are seen between the lung and the pulmonary interstitium. Ground glass opacities may be present. While these ground glass opacities were initially felt to be predictive of reversible, active alveolitis, further studies have shown that ground glass opacities can also represent intralobular/alveolar wall fibrosis. Gallium67 activity can be used to assess activity of patients with UIP. CT scans of patients with UIP show a high incidence of lymphadenopathy, and these hyperplastic nodes can grow up to 4 centimeters in size. It is important to screen these people carefully for the development of malignancy, as 5-13% of patients will develop lung cancer.

References:
Armstrong P, Wilson AG, Dee P, Hansell DM. In Imaging of Diseases
of the Chest. Mosby, St. Louis 1995.

Webb WR, Muller NL, Naidich,DP, High Resolution CT of the Lung.
Lippincott-Raven Philadelphia 1996.

"interstitial infiltrate", lower lungs.

same as above. idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis.

nejm-cfa-ipf

"hilar adenopathy" with "right paratracheal adenopathy"

Sarcoidosis is a disease of unknown etiology characterized by granulomatous inflammation of multiple organ systems with a high predilection for the lungs. The first manifestations of the disease occur in the age group 20-40 with a definite female and black predominance.

Symptoms develop in approximately 50% of those afflicted with the disease. Of those with symptoms, the most common are weight loss, fatigue, and malaise. With progression of the disease to involve the pulmonary parenchyma, dry cough and shortness of breath may develop.

The earliest radiographic manifestations generally consist of bilateral hilar adenopathy with associated right paratracheal adenopathy - the so-called "1,2,3 sign" on chest x-ray. Approximately 80% of those with hilar adenopathy (with or without associated visible pulmonary abnormality) will eventually show complete radiographic resolution. It is generally agreed that approximately 20% of patients will go on to develop irreversible pulmonary fibrosis with associated bronchiectasis, bulla formation, and emphysema. When severe, pulmonary hypertension and cor pulmonale may ensue. The prognosis in patients with sarcoidosis varies considerably, but it is generally thought that the overall mortality rate ranges from 5-10% with most of these patients dying from cardiac decompensation secondary to pulmonary fibrosis.

"perihilar consolidation"

Allergic bronchopulmonary aspergillosis (ABPA) accounts for the majority of eosinophilic lung disease. The basis of ABPA is a hypersensitivity to the Aspergillus species that grows in the dilated proximal airways. Aspergillus fumigatus is the species present in nearly 90%. But other common species include A. flavus and A niger. ABPA commonly occurs in a patient with a long history of asthma. There are a number of criteria for ABPA. The major criteria include 1) asthma, 2) blood eosinophilia, 3) immediate skin reactivity to Aspergillus antigen, 4) precipitin antibodies to Aspergillus antigen, 5) raised serum IgE, 6) pulmonary opacities and 7) central bronchiectasis.

Radiographic findings include perihilar consolidations, which often recur in the same locations. Mucoid impaction in areas distal to the diseased central airways is the most characteristic finding in ABPA. The opacities of mucoid impaction correspond to the "toothpaste tube" sign commonly associated with ABPA.

CT scanning has replaced bronchography for the diagnosis of ABPA. Upper lobe central bronchiectasis is a characteristic finding on CT. Atelectasis, scarring and volume loss can occur in those areas most severely affected. Mycetomas will occur in a minority of patients.

References:
Armstrong P, Wilson, AG, Dee P, and Hansell, DM. Imaging of Diseases of the Chest,
2nd Ed., Mosby, 1995, 529-534.

Greenberger PA: Allergic Bronchopulmonary Aspergillosis and Fungoses.
Clin Chest Med 9:599-608, 1988.

parasite-induced bronchospasm: cough, wheeze, malaise, cxr-infiltrates, hypereosinophilia on peripheral smear
ascaris(mebendezole) or strongyloides(thiabendazole/albendazole).

Bilateral interstital and alveolar consolidation, c/w PCP.

Diagnosis: Pneumocystis Carinii Pneumonia (PCP) or PCP with more localized bacterial pneumonia.

Discussion: Pneumocystis carinii, a unicellular fungus, causative of most common AlDS-related opportunistic infection. Clinical presentation of cough, tachypnea and malaise.

• Hypoxemia with an increased alveolar-arterial oxygen gradient
• Respiratory alkalosis
• Impaired diffusing capacity
• Changes in total lung capacity and vital capacity

CD 4 less than 200. pentamidine aerosolized assoc with ptx.
IC Host -transplant, immunodeficiencies, HIV
ct can show.The typical appearance is patchy areas of ground-glass attenuation with a background of interlobular septal thickening

As in this patient, initial CXR can be normal, with a positive Gallium scan. CXR then progresses to a reticulonodular interstititial process, then to diffuse alveolar consolidation, predominantly affecting the hila and bases. Hilar adenopathy is uncommon.

Radionuclide lung studies provide higher sensitivity than CXR (sensitivity 90%/specificity 47%), and dete.ct PCP earlier (30-40% of CXR normal). Also of value to monitor treatment. Biopsy or bronchoscopy needed for diagnosis, but negative GA67 (can spare the biopsy because PCP unlikely).

Patchy or localized uptake can be seen early with diffuse bilateral uptake most common later in disease.

GA67 images areas of active inflammation and infection, with radioisotope transported bound to iron-binding proteins. Infection areas have increased capillary permeability and therefore localize Ga-67.

Patterns:

• Heterogeneous diffuse uptake
• Localized uptake: PCP or bacterial pneumonia
• Ill-defined, perihilar uptake: PCP or CMV
• Focal, lymph node uptake: TB or Iymphoma, MAI
• 
  

Obtain sputum sample by sputum-induction for histopathologic testing if PCP is strongly suspected. Pneumocystis organisms are frequently found in sputum induced by inhalation of a hypertonic saline solution.

• Expectorated sputum has a very low sensitivity and should not be submitted for diagnosis.
• Sputum induction is the quickest and least-invasive method for definitively diagnosing PCP.⁵
• Sensitivity varies widely (<50% to >90%) and depends on proficiency in using the technique and the experience of the laboratory.
• Specificity is high (99-100%).
• This study may be less sensitive in patients without HIV infection, as the immunodeficiency caused by HIV infection typically leads to a greater alveolar load of Pneumocystis organisms.
• It may also be less sensitive in patients receiving aerosolized pentamidine for prophylaxis.

BAL is the most common invasive procedure used to diagnose PCP.

• BAL has a diagnostic yield that exceeds 90% (may be increased if multiple lobes are sampled).⁶
• Obtain BAL if PCP is strongly suspected and the induced sputum sample findings are negative.
• BAL yields a lower sensitivity in patients receiving aerosolized pentamidine, in which case a transbronchial biopsy may be performed in conjunction with BAL.⁷
• BAL may be used in patients who are unable to cooperate with an induced sputum sample (eg, because of altered mental status).
• BAL may be less useful in cases of suspected PCP relapse
• 
  
• Treatment is based on the alveolar-arterial gradient, which may be mild (<35 mm Hg), moderate/severe (35-45 mm Hg), or severe (>45 mm Hg).

• Severe disease is also indicated by a room air pO₂ of less than 70 mm Hg.

PCP treatment-
bactrim. Intravenous: (TMP) 20 mg/kg/d, (SMX) 75-100 mg/kg/d IV divided tid/qid
Oral: 2 double-strength tab tid

pentamidine-blocking oxidative phosphorylation and inhibiting incorporation of nucleic acids into RNA and DNA, causing inhibition of protein and phospholipid synthesisAntibiotics are primarily recommended for treatment for mild, moderate, or severe PCP. Trimethoprim-sulfamethoxazole (TMP-SMX) has been shown to be as effective as intravenous pentamidine and more effective than other alternative treatment regimens.⁸ The parenteral route may be considered in patients who present with serious illness or in those with gastrointestinal side effects. TMP-SMX is the preferred initial therapy during pregnancy according to consensus guidelines. The patient's neonatologist should be informed if the medication is used near delivery because of potential for hyperbilirubinemia and kernicterus.

Prophylaxis may be discontinued in patients with HIV infection whose CD4 count exceeds 200/µL for 3 consecutive months while on HAART. Prophylaxis should be restarted if the CD4 count drops below 200/µL. Prophylaxis should be continued for life in patients who developed PCP while their CD4 level exceeded 200/µL.


 The combination of clindamycin and primaquine is likely to be more effective than intravenous pentamidine in the treatment of infections that are resistant to TMP-SMX



tuberculosis
tuberculosis mimics: 
lung flukes: paragonimus westermani- cough, bloody sputum, lgt, malaise, infiltrates- from raw/undercooked crab/crayfish: asia, africa, latin america, southern usa,

pseudomonas pseudomallei: melioidosis southeast asia, rice paddies.

influenza
meningitis
herpes
zoster
strep pharyngitis
otitis media
endocarditis
rheumatic vs scarlet fever

left atrial thrombus US image-nejm
 atrial myxoma vs left atrial thrombus
dysentery-infectious diarrhea
pyelonephritis
PID
urinary tract infection
prostatitis
biliary infections
cellulitis
visual stimulus- redness to skin following breast cancer radiation.
nejm-cellullitis


osteomyelitis
septic joint
zoonoses
leptospirosis: rats, spirochete, fever, weil's disease.

Lyme disease:

spirochete. borrelia burgdorferi. peak season may-august, fever, mental status changes,arthritis, heart block, rash.

lyme disease

rabies: commonest host: dog worldwide. in USA: skunks/raccoons/bats/foxes.  atlantic: raccoon: epizootic, less common: rodents (squirrels,hamsters, guinea pigs, chipmunks, rats, mice), (lagomorphs: rabbit/hare)
encephalomyelitis, rna virus, rhabdovirus, neurotropic. greatest risk: head/neck bite. 25-50% untreated develop.
inhalation airborne rabies: spelunking. corneal grafts. 60% no source identified.
incubation period 4-8 weeks. (days to a year). axoplasmic transport to cns. transport to salivary glands. shorter incubation with head and neck bite, child. presentation: classic(furious) 80%, paralytic (20%). phases. classic. prodrome: uri.gi pain/paresthesias, pruritus at dorsal root ganglion. acute neurologic:anxious,agitated,dysphagia.,hydrophobia,aggression/lucidity, hallucinations.. swallowinng-violent contractions of muscles inspiration. laryngeal/pharygneal spasm, facial grimace, opisthotonus, seizures.draft of air on face-aerophobia.

clinical phase- arrhythmias, autonomic dysfxn, coma.

paralytic--prodrome, pain,paralysis, with ascending symmetric or assymmeteric partalysis. mu;ltiple findings, mimics guillain barre/acute immune polyneuritis.  slower than classic rabies, survuval up to amonth. ddx:polio, simian herpes encephalitis, postvaccine paralysis, guillian barre.

early dx difficult. anderson reviewed 1960-1979 14% first dx correct. premortem dx more likely with exposure hx and hydrophobia

no successful rx. only three survivors.
dx: csf/saliva for virus, serum and csf for titers, biopsy of skin of neck covered by hair. serum antibodies day 6, csf after serum. if csf positive in vaccinated patient means infection. negri bodies absent in 20% of proved cases. eosinoophilic cytoplasmic inclusion bodies.

WEST NILE VIRUS
RNA virus, single strand, flavi viridae
spring to fall
msoquitoes, culex.
west nile district of uganda. 1937. -1990's infrequent in israel, africa
1999-62 cases USA, 2000-21 cases USA, 2001-66 cases USA, East Coast.
2002->4000 cases throughout USA.
incubation 2-14 days. most asx. mild illness fever in 20%, malaise, anorexia, nausea, vomiting, headache, myalgia, rash.
<1% encephalitis,. meningiits, accute flaccid paralysis.
acute flaccid paralysis: asymmetrical weakness, upper and lower limbs,  +/- encapholmyelitis, hyporeflexia, areflexia, acute bowel/bladder, no pain or sensory findings. : due to destruction of anterior horn motor neurons, with polio like syndrome. not equivalent to guillain barre

case fatality rates=4-18% among hospitalized.     2002 outbreak cfr 9%
diagnosis IgM, persists for 500 days. LP-pleocytosis with lymphocytes and high protein levels.
CT normal. rx supportive.

tranmission documented by CDC in 29 cases of blood tranfusions during 2002-2003 outbreak and organ transplants, screening of blood donors recommended.

unusual pathogens
-malaria vs babesiosis. in babesiosis you can see intracellular organism ring forms in the rbc'swith tetrads in a maltese cross formation. note that howell jolly bodies are dna in erythrocytes in asplenic patients.
-keratoderma blenorrhagica nejm
refers to psoriasiform and vesicular pustular lesions of the palms and soles seen in Reiter's syndrome, along with symptoms involving the joints, eyes, and urinary tract.
this should proompt a search for sexually transmitted diseases such as syphilis or gi pathogens.
-the differential diagnosis of a rash involving the palms or soles includes
rickettsia (RMSF), meningococcemia, syphilis, enterovirus, atypical scabies.

-differential for scabies-
bird mites.
-high fever, headache, petechiae, myalgia, anemia- dengue fever.

-furuncular miasis. furuncular miasis nejm visual stimulus, 
furuncular miasis vs. leishmaniasis, cutaneous larva migrans, tungiasis, epidermoid cyst.
leishmaniasis.
cutaneous leismaniasis: painless shallow skin ulcer rolled edge, enlarging over weeks, resists abx.


sandflies. papule-ulcer, secondary bacterial infection

hiking or backpacking in southeast asia: japanese encephalitis

walking barefoot: hookworm, strongoloidiasis

sandals or open toed shoes: rmsf, lyme dz,

beaches: cat/dog excrement hookworms-larval forms- -cutaneous larva migrans pruritic tracks

DEET: mosquitoes, ticks, sandflies, fleas, blackflies.. not stingers. <30%     seizures.
tuberculosis mimics: 
lung flukes: paragonimus westermani- cough, bloody sputum, lgt, malaise, infiltrates- from raw/undercooked crab/crayfish: asia, africa, latin america, southern usa,

pseudomonas pseudomallei: melioidosis southeast asia, rice paddies.

MINOR CASES

paronychia



felon
visual stimulus nejm keratocanthoma
chalazion
hordeolum


Muehrcke's lines

A 46-year-old woman with metastatic sarcoma who had been treated with five cycles of doxorubicin, ifosfamide, and mesna chemotherapy presented with two symmetrical, horizontal white lines on all of her fingernails but not on her toenails. A diagnosis of Muehrcke's lines was made. Muehrcke's lines are the two smooth white bands that run parallel to the lunula across the width of the nail. The lines are nonpalpable and, unlike Beau's lines, do not indent the nail itself. Normal-appearing pink nail-bed tissue is seen between the two white lines, and thumb involvement is rare. Muehrcke's lines are a nonspecific finding that may be associated with periods of metabolic stress, which transiently impairs the ability of the body (and particularly of the liver) to synthesize proteins. Although the use of chemotherapy is one potential cause of Muehrcke's lines, as illustrated in this patient, so are infections and trauma. Three months after presenting with Muehrcke's lines, the patient died from progressive metastatic disease.



Beau's lines
trauma, fever, kawasaki disease, hypocalcemia,


foreign body
subungual hematoma
abscess
laceration