Shock in Pediatric Patients

Senor Resident Didactics September 2024

Michael J. Auth, DO

Pediatric Critical Care

Dell Children’s Medical Center

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Disclosures

• None

Objectives: Shock

• Define Shock
• Etiology of Shock
• Stages of Shock
• Recognition / Signs and Symptoms
• Review Diagnostic Approach
• Case Studies with Management Strategies

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Definition: Shock

• Inadequate supply of blood and oxygen to the body's organs and tissues

Blood Pressure

Definition: Shock - Supply vs Demand

Oxygen Delivery

= DO2

Oxygen Consumption

= VO2

DO2 less than VO2

Definition (Final Answer) : Shock

does NOT meet

O2 Delivery (DO2)

O2 Demand (VO2)

Etiology of Shock

• Hypovolemic - bleeding, dehydration, burns, GI losses

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.
• Obstructive - pulmonary embolism/HTN, cardiac tamponade - constrictive pericarditis, tension pneumothorax, coarctation, aortic dissection
• Dissociative - mitochondrial toxicity (cyanide, and salicylate poisoning)

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.
• Obstructive - pulmonary embolism/HTN, cardiac tamponade - constrictive pericarditis, tension pneumothorax, coarctation, aortic dissection

Stages of Shock

1. Redistribution of blood flow
1. Activation of sympathetic nervous system
2. Release epinephrine / norepinephrine
3. Mild tachycardia acceptable
4. Vascular bed vasoconstriction (prioritizing brain, heart, kidneys)
2. Stress Response
• Cortisol
3. Fluid retention
• Aldosterone
• ADH

1. Profound tachycardia
2. Hypotension with weak pulses
3. Tachypnea
4. Altered mental status
5. Cold and pale skin
6. AKI
7. …

1. Severe Hypotension
2. Multi-Organ Failure
1. Heart
2. Brain
3. Liver
4. Kidney
3. Profound lactic acidosis

Compensated Shock (Early)

Uncompensated Shock (Late)

Irreversible Shock (Dead)

Recognition of Shock

Signs:

Heart rate (i.e. tachycardia)

Blood pressure (i.e. hypotension)

Cold, clammy skin (poor capillary refill)

Altered mental status → unconscious

Symptoms:

Dizziness, Weakness

Thirst

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Vital

Signs

Adults

Peds

More to come

Monitoring for Signs of Shock…

• Heart rate (ecg)
• Blood pressure (invasive)
• Respiratory rate (mechanical ventilation)
• Pulse Oximetry (Oxygen saturations)
• Temperature
• Central venous pressure (CVP)
• Near infrared spectroscopy (NIRS)
• Pulmonary artery pressure (i.e. Swan-Ganz catheter )

Vital

Signs

Physical Exam

Neurologic

Gallop

Pulses and perfusion

Edema

Laboratory

Metabolic acidosis

Lactic acidosis

BUN / Creatinine

Urine

Oliguria (low output)

Dark urine

Diagnostic Approach

Case Study 1:

A 7 year old girl is admitted to the floor with a presumed diagnosis of influenza. She is previously healthy with no PMHx, and immunizations are up to date. Her old brother tested positive for influenza a few days prior to her becoming ill. She now has 2-3 days of fever and cough, with decreased PO intake. After being seein in the ED, she was admitted to the floor for IV Fluids and observation.

At 6:30 AM a CRT is called for her room. Parents are hysterical, stating that she will not wake up.

A

Airway

B

Breathing

C

Circulation

Case Study 1:

Initial Assessment

A 7 year old girl is admitted to the floor with a diagnosis of influenza. She is previously healthy with no PMHx, and immunizations are up to date. Her old brother tested positive for influenza a few days prior to her becoming ill. She now has 2-3 days of fever and cough, with decreased PO intake. After being seein in the ED, she was admitted to the floor for IV Fluids and observation.

At 6:30 AM a CRT is called for her room. Parents are hysterical, yelling that she is hard to wake up.

A

Airway

B

Breathing

C

Circulation

Vitals

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Heart Rate: 165

Blood Pressure: 95/33

Respiratory Rate: 33

Pulse Ox: 96%

Temperature: 39.2C

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Physical Exam

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Neuro: Lethargic

Resp: Tachypneic, clear

CV: Bounding pulses

Skin: Rapid cap refill

Labs

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Bicarbonate

pH

Lactate

Hgb

Sodium

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Case Study 2:

Anaphylactic Shock (Distributive)

A 4 year old girl is brought to the ED by parents after accidentally ingesting a peanut butter snack at a friend’s birthday party. Within 10 minutes she started having symptoms so parents brought to ED.

IM Epinephrine

IV Fluid Bolus

Benadryl

A

Airway

B

Breathing

C

Circulation

Vitals

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Heart Rate: 165

Blood Pressure: 95/33

Respiratory Rate: 33

Pulse Ox: 96%

Temperature: 39.2C

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Physical Exam

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Skin: Urticaria, itching

Resp: Cough, wheezing

CV: Tachy, ↑ pulses

GI: Vomiting, abd pain

Labs

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Bicarbonate

pH

Lactate

Hgb

Sodium

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Observed for 6 hours - no rebound - DC Home

Rx for auto-injector

Refer allergist

Case Study 3:

Cardiogenic Shock

A 15 year old male presents with complaint of abdominal pain, shortness of breath and cough. He was sick with flu-like symptoms about a week prior, but now has progressively worse shortness of breath.

A

Airway

B

Breathing

C

Circulation

Vitals

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Heart Rate: 165

Blood Pressure: 88/65

Respiratory Rate: 33

Pulse Ox: 93%

Temperature: 38.3C

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Physical Exam

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Neuro: Awake, ill-appearing

Resp: Tachypneic

CV: Weak pulses

Skin: Cool extremities

Labs

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Bicarbonate

pH

Lactate

Hgb

Sodium

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Labs: PENDING

Treatment for Tachycardia, Hypotension, Poor Perfusion?

Chest X-Ray

Oxygen Delivery: Big Picture

Sats = 100%

Sats = 80%

AVO2 = 20%

Delivery

Consumption

Venous

Oxygen Delivery (DO2) = Cardiac Output * Oxygen Content

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

Heart Rate * Stroke Volume

1.34 * Hgb * Sats/100 + (0.003 * PaO2)

Preload

Contractility

Afterload

Oxygen binding capacity of hemoglobin (ml per gram)

Oxygen Content: Summary

• Hemoglobin (Hgb = g/dL)
• Iron (Fe) protein to carry oxygen
• Each Hgb molecule holds 4 oxygen
• Hgb is INSIDE of RBC (270 million per red blood cell)
• HCT = % blood volume of RBCs

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• Oxygen Content of Blood
• O2 Content = (1.34 * Hgb * Sats) + (PaO2 * 0.003) = ml O2/dL
• MOST of the O2 is bound to Hgb
• There is very little oxygen dissolved in the plasma
• Dropping the Hgb in half will decrease the O2 Content by 50%
• Sats of 50% will DECREASE the O2 Content by 50%

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Final Pearl: O2 Content mostly depends upon Hgb and Sats

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

• Chronotropy
• Sinus
• Atrial kick (5-30%)
• Bradycardia
• Pacing
• Isoproteronol, epinephrine

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

• Fluid is given into veins
• Veins contain 70% blood volume
• Veins 30x more compliant arteries
• Goal = increased Cardiac Output

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67%

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26%

7%

Blood Volume

Interstitial

Intracellular

Where’s the water?

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

Muscle Contractility

• Actin
• Myosin
• Calcium

Starling’s Curve: Optimal Preload

Starling’s Curve: Fluid Responsive?

Preload

Fluid Responsive

Fluid Unresponsive

Stroke Volume

Cardiac Output

Systemic Vascular Resistance

1. Preload

3. Afterload

2. Contractility (inotropy)

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

Cardiac Output

Oxygen Content

O2 Delivery: Summary

2. Preload

4. Afterload

3. Contractility

Heart_Rate PreLoad Contractility Afterload Hgb Sats PaO2

1. Heart Rate

5. Hgb

6. Sats

7. PaO2

Heart Rate * Stroke Volume

1.34 * Hgb * Sats/100 + (0.003 * PaO2)

Case Study 4

• You are shadowing EMS and dispatched to the rodeo
• Previously healthy 6 year old
• Just out looking to have some ‘Texas fun’

Mutton

Bustin’

What starts out as ‘fun’...

Gets a little out of control…

Followed by a little ‘revenge’...

Patient arrives to the Emergency Department

• Groaning
• Tachycardic with frequent PVCs
• Hypotensive
• Difficulty Breathing with low O2 saturations
• Lower extremity deformity
• Distended abdomen (+ FAST exam for fluid in the abdomen)

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• Exam: altered-lethargic, weak pulses, clammy skin

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Initial Treatment

• C-spine precautions maintained
• Airway supported
• Oxygen provided
• Monitors placed
• IV Access obtained

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Patient candidate for volume resuscitation?

Is the timing appropriate?

Volume of choice?

Repeat bolus?

Case Study 4: Hypovolemic Shock

• Volume
• Volume
• Volume

Mutton

Bustin’

Hypovolemic Shock: Pathophysiology

Why is a patient hypotensive due to hypovolemia?

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1. Decreased Preload
2. Decreased Afterload
3. Decreased Contractility
4. Decreased Metabolic Demand

Decreased PRELOAD

Case Study 5:

A 16 year old female brought to the ED with fever, chills, rapid breathing, and confusion. Her symptoms started 2 days ago with generalized malaise, nausea, and abdominal pain. She reports poor oral intake last 2 days and dark urine.

A

Airway

B

Breathing

C

Circulation

Vitals

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Heart Rate: 165

Blood Pressure: 88/35

Respiratory Rate: 33

Pulse Ox: 93%

Temperature: 39.2C

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Physical Exam

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Neuro: Awake, ill-appearing

Resp: Tachypneic

CV: Bounding pulses

Skin: Rapid Cap Refill

Labs

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Bicarbonate

pH

Lactate

Hgb

Sodium

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Labs: PENDING

Treatment for Tachycardia, Hypotension, Poor Perfusion?

Chest X-Ray

Low C.O.

Normal C.O.

High C.O.

Cold, clamped down

Slow Cap Refill

Narrow pulse pressure

Warm, vasodilated

Rapid Cap Refill

Wide pulse pressure

Vasoactive receptors (adrenergic + V1)

Beta 1: Heart

Beta 2: Lungs

Alpha 1, V1*: Vasoconstriction

Alpha 2: Vasodilation

Beta 1: Inotropy

Alpha 1, V1*: Vasoconstriction

Epinephrine (inotropy >> vasoconstriction)

Beta 1: Heart

Beta 2: Lungs

Alpha 1: Vasoconstriction

Alpha 2: Vasodilation

Norepinephrine (vasoconstriction >> inotropy)

Beta 1: Heart

Alpha 1: Vasoconstriction

Vasopressin (V1 - vasoconstriction)

V1: Vasoconstriction

Case Study 5:

Septic Shock

A 16 year old female brought to the ED with fever, chills, rapid breathing, and confusion. Her symptoms started 2 days ago with generalized malaise, nausea, and abdominal pain. She reports poor PO last 2 days and dark urine.

A

Airway

B

Breathing

C

Circulation

Vitals

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Heart Rate: 165

Blood Pressure: 88/35

Respiratory Rate: 33

Pulse Ox: 93%

Temperature: 39.2C

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Physical Exam

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Neuro: Awake, ill-appearing

Resp: Tachypneic

CV: Bounding pulses

Skin: Rapid Cap Refill

Labs

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Bicarbonate

pH

Lactate

Hgb

Sodium

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Treatment:

Treatment: Volume… the correct amount... then… Vasoactive meds

Rapid Review…

Hypovolemic Shock

• Etiology - bleeding, dehydration, burns, GI losses
• Pathophysiology: Inadequate cardiac filling
• Signs: Tachycardia, Hypotension, Delayed CR, cool extremities
• Compensated vs Hypotensive
• Symptoms: Thirst, oliguria, altered mental status

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• Treatment: Volume
• Rationale: Restore CARDIAC OUTPUT

Cardiogenic Shock

• Etiology - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Pathophysiology: Heart Failure leading to decreased cardiac output
• Signs: Tachycardia, Hypotension, Delayed CR, cool extremities
• narrow pulse pressure
• Symptoms: Abdominal pain, thirst, oliguria, altered mental status
• Treatment:
• NOT NOT NOT Volume
• Inotropic meds
• Diuresis (?)
• Afterload reduction (?)

Distributive Shock

• Etiology - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.
• Pathophysiology: Maldistribution of blood flow due to vasodilation
• Signs: tachycardia, hypotension
• Early: warm with bounding pulses and rapid capillary refill
• Late: cold with weak pulses
• Symptoms: Thirst, oliguria, altered mental status

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• Treatment:
• Volume… the correct amount
• Vasoactive medications to increase afterload

Obstructive Shock

• Etiology - pulmonary embolism/HTN, cardiac tamponade - constrictive pericarditis, tension pneumothorax, coarctation, aortic dissection
• Mechanism: Mechanical obstruction of blood flow leading to reduced cardiac output
• Signs: Tachycardia, Hypotension, Delayed CR, cool extremities
• Signs: Jugular venous distention, muffled heart sounds, tracheal deviation
• Symptoms: Thirst, oliguria, altered mental status
• Symptoms: Rapid onset of severe symptoms? Chest Pain? SOB?

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• Treatment:
• Volume… ???
• Inotropic meds… ???
• DIAGNOSE (chest xray, ECHO, POCUS)
• FIX the PROBLEM

Review: Etiology of Shock

• Hypovolemic - bleeding, dehydration, burns, GI losses

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.
• Obstructive - pulmonary embolism/HTN, cardiac tamponade - constrictive pericarditis, tension pneumothorax, coarctation, aortic dissection
• Dissociative - mitochondrial toxicity (cyanide, and salicylate poisoning)

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.

• Hypovolemic - bleeding, dehydration, burns, GI losses
• Cardiogenic - cardiomyopathy, heart Sx, arrhythmia, trauma, drugs, MI
• Distributive - sepsis, anaphylaxis, neurogenic, drugs, adrenal insuff.
• Obstructive - pulmonary embolism/HTN, cardiac tamponade - constrictive pericarditis, tension pneumothorax, coarctation, aortic dissection

Shock: Uncompensated (Late Shock)

Shock: Compensated (Early Shock)

• Body activates compensatory mechanisms to maintain blood pressure and organ perfusion

• Body’s compensatory mechanisms are no longer able to maintain adequate tissue perfusion and oxygenation.

Note: Intervene at this time!

Note: Requires URGENT intervention

Peds

Conclusion

mjauth@ascension.org

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• Early recognition and intervention are crucial.

• Understand the type of shock to guide management.

• Continuous reassessment is vital.