Case 1
Nulliparous patient in Labor & Delivery triage
Introduction
Our goal is to consider a range of common and don’t-miss conditions encountered in Labor & Delivery triage.
We present your first triage patient, and ask you to walk through progressive diagnostic and management decisions. Go through the various options in the order indicated! Sidenotes are on orange slides.
Skills
By the end of this case, you will have the following skillset:
-Interpretation of fetal heart tracings & tocometry in clinical context
-Generation of differential diagnosis and management plan for patient in triage and in various stages of labor
-Writing generic labor admission orders
Topics covered
-Basic history & exam of patient presenting to triage
-Electronic fetal monitoring
-GBS screening and prophylaxis
-Term and preterm labor
-Spontaneous vs. premature rupture of membranes
-Variations of fetal presentation
-External cephalic version
-Regional pain control during labor
-Normal and abnormal labor progress
-Vaginal delivery (spontaneous vs. operative)
-Cesarean delivery
-Shoulder dystocia
-Obstetric lacerations
-Postpartum hemorrhage
Meet your patient!
A 27 year-old G1P0 at 39+2 weeks gestation presents to triage. She reports feeling a gush of fluid down her legs a few hours ago. Since this morning she has timed her contractions at about 10 minutes apart, and says they’re progressively intensifying. She also reports somewhat decreased fetal movement since last night.
What is your differential diagnosis?
List at least 3 before you click ahead!
A differential:
1) Membrane rupture ?
2) Vaginal discharge?
-physiologic vs. infectious
3) Urination?
4) Labor?
-True vs. false
5) Fetal distress? Normal decrease in perceived fetal motion?
→ Admission for labor
→ Reassurrance vs. antimicrobial treatment
→ Reassurrance (or antibiotics, if UTI)
→ Admission (regardless of membrane status) vs. discharge home
→ Tests of fetal well-being
What are your first steps?
Think of at least 2 before clicking ahead!
First steps
Assess for amniotic fluid in vagina
Assess fetal status
Assess uterine contractions
→ Digital vs. sterile speculum exam
→ Ultrasound vs. heart tracing
→ History; tocometry
Assessing for membrane rupture
Can do digital exam:
→ Obtain sample of vaginal fluid with gloved finger; place on nitrazine paper (can also place on glass slide to check ferning)
Can’t do digital exam:
- <34wks
- Bleeding
→ Insert speculum without gel. Look for clear fluid or blood pooling in vagina or flowing from cervix; visualize cervical dilation and any lesions
1st reading assignment
Go to www.ob-efm.com
→ Read all 5 subsections of “EFM basics,” from History to Interventions
→ Review all 4 self-guided tutorials
Problem 1: Fix this table!
Reorganize the middle column (I-V) so it matches correctly with the first column (a-e). Then do the same for the far right column (α-ε).
a-e: EFM pattern | I-V: Fetal CNS process attributed | α-ε: Clinical explanations |
a. Early deceleration | I. Vagal stimulation, can’t compensate in hypoxia | α. Head compressed by contraction (mild hypoxemia) |
b. Moderate variability | II. Vagal stimulation, compensating in hypoxia | β. Head compressed by contraction (well-oxygenated) |
c. Reflex late deceleration | III. Vagal stimulation, well-oxygenated | γ. Fetal movement |
d. Nonreflex late deceleration | IV. Balanced sympathetic- parasympathetic interaction | δ. Intact CNS; highly indicative of well-being |
e. Acceleration | V. Transiently increased sympathetic tone | ε. Head compressed by contraction (uteroplacental insufficiency) |
Problem 2: Variable decels
Fill in the blanks!
Problem 3: In your own words…
Please summarize in your own words, to the best of your understanding, the known and theoretical benefits of EFM over intermittent auscultation and over no monitoring.
Problem 4: Initial tracing
Nurses placed external doppler belts on the patient upon her arrival. Now you have the following tracing from the electronic fetal monitor:
(reactive strip - at least 2 accels, mod. var, no decels - with ~q2-5min ctx)
Choose your adventure: cervical exam
Her cervical exam was 5cm/50/0.
Clear fluid from vagina, turns blue on nitrazine paper
Minimal clear fluid from vagina; nitrazine paper stayed yellow
Problem 5: Spontaneous rupture of membranes at term
She denied recent intercourse, abnormal discharge or vaginal irritation; you believe this is likely a true positive.
You decide to admit her. Write the admission note!
-Refer to template included in course materials
-Assume inadequate prenatal care; you only have what is provided in the H&P. List what other tests you need to order during this admission, and why!
When done, you can continue this scenario or go back to cervical exam
Membranes intact, not bleeding
Admit for spontaneous labor at term, or send her home?
-Remember our patient’s history: contractions ~q10min, progressively intense. What else do you want to know?
-Remember differentials for membrane rupture
→ Physiologic discharge, urinary incontinence: reassure
→ Ask about symptoms suggesting reproductive or urinary tract infection (which may prompt you to collect urine culture or vaginal swabs)
True vs. false labor
True labor
-Progressive cervical change
→ progressive pain
-Contractions
→ regular, frequent (q2-4min)
→ long (~1 min)
-Felt in fundus & back (> groin)
-Can’t stop
False labor
-Little to no change in dilation or pain level
-Contractions
→ Irregular, infrequent, shorter
-Felt in lower abdomen
-Stops spontaneously or with hydration/tocolysis
Third trimester bleeding
Third trimester bleeding differential
Placenta previa
Placental abruption
Vasa previa
Cervical bleeding (benign, traumatic, infectious)
Before you click ahead, list your next steps
Third trimester bleeding: initial management
-Assess maternal vitals; resuscitate her if unstable
-Assess fetal status
-Mother’s blood type & coagulation studies
→ To help answer whether she needs Rhogam and if so, how much
→ To help guide transfusion therapy, if necessary
-Look for bleeding source (ultrasound)
→ Abruption not reliably detected by U/S or visual inspection
→ Examine for abdominal tenderness (Next slide)
Rhogam
Placenta previa
0.4% of term pregnancies
-Risk factors include uterine scarring, tobacco use, multiparity, multiple gestation, chronic hypertension
-Bleeding episodes usually minor and seen before term, and often self-resolve
Placental edge 2cm or closer to internal os
-Safe & accurate diagnosis by transvaginal U/S
-Placenta tends to cause fetal malpresentation
Delivery options
-May attempt vaginal delivery if placental edge 1+ cm from internal os (most succeed)
-May schedule cesarean (after 37 wks or documentation of fetal lung maturity)
-Emergent cesarean if brisk, persistent vaginal bleed (Next slide)
Placental abruption
Up to 3.8% of pregnancies, per pathology
-Varying degrees of hemorrhage; most cases not clinically apparent or significant
-Risk factors: hypertension, pre-eclampsia, trauma, stimulant abuse, oligohydramnios
Placenta separates from myometrium before delivery
-Usual signs: uterine tenderness, vaginal bleeding, possibly recurrent decels on FHT
-Normal U/S only has 53% negative predictive value :(
Delivery options
-May manage expectantly with plan for vaginal delivery as long as fetal status reassuring
-Emergent cesarean if maternal or fetal condition deteriorates
Vasa previa
1 in 2,000 - 5,000 deliveries
-When cord with velamentous insertion (~1% of singleton pregnancies) courses near os
-Risk factors: in-vitro fertilization, multifetal gestation, succenturiate placentation
Diagnosis & management
-If detected on antenatal U/S & cesarean delivery is planned, neonatal survival ~97%
-If undetected before labor (=hemorrhage?), neonatal survival ~44%
-Hemorrhage from cord causes rapid fetal decline; urgent cesarean indicated
(Go back to cervical exam, or continue to gestational age determination on next slide)
How to confirm gestational age?
-Ultrasound margin of error is +/- 8% (?) Reliable menstrual period more precise
→ Even if periods are REGULAR, they may not be 28 days cycles - so ask and account for that! (most automated apps assume 28 days)
→ 1st trim. U/S agreeing with LMP within 1 week = close enough (use LMP)
→ 2nd trim. U/S agreeing with LMP within 10 days = close enough (use LMP)
-If menses were irregular, go with ultrasound dates
-If you could only go by 3rd-trimester ultrasound, estimates would be +/- roughly 3 weeks!
Choose your adventure: term or not?
Preterm labor (20-37 weeks)
MOST cases do not result in imminent delivery
-30% resolve with expectant management
-50% of patients admitted for PTL still delivered at term
-12% of all live births are preterm; half are preceded by preterm labor (rather than premature rupture of membranes or indicated delivery)
PTL management
Suggested scheme, broken down by gestational age into “zones:”
A for Awesome (37-41 weeks): Term
B for Borderline (34-37 weeks): Preterm, won’t benefit from corticosteroids but may benefit from expectant management if labor resolves
C for Corticosteroids (24-34 weeks): Preterm, 48h of tocolysis to allow maximal fetal steroid benefit
D (under 24 weeks): Preterm, won’t benefit from steroids or tocolysis; expectant management anticipating poor prognosis if delivered
Tocolysis (only purpose is for 48h of steroids!)
Firstline tocolytics | Maternal risks | Fetal/neonatal risks | Contraindications |
PO or PR indomethacin, 50-100mg x1 + 25-50mg q6h (inhibits PG synthase) | Reflux, nausea/ vomiting | Necrotizing enterocolitis (after ~30 wks); premature ductus arteriosus closure; oligohydramnios | GI ulcers, bleeding disorder, hepatic or renal dysfunction, ASA hypersensitivity |
PO nifedipine, 30mg x1 + 10-20mg q4-6h (CCB) | Hypotension, bradycardia, flushing/dizziness | (none known) | Hypotension, CHF, aortic stenosis |
SubQ terbutaline, 0.25mg q20min-3h (β-mimetic) | Hypotension, tachycardia, cardiac ischemia, pulm. edema, hypokalemia, hyperglycemia | Tachycardia | Maternal tachycardia, cardiac disease, or DM |
Magnesium sulfate NOT a firstline tocolytic (Ca antagonist) | Loss of DTR’s; flushing; N/V | Fetal cardiac/CNS depression | Myasthenia gravis |
A note on magnesium sulfate use for fetal “neuroprotection”
MgSO4 given when labor <30 weeks gestation → nonsignificant mortality benefit.
Among the survivors, NO LONG-TERM NEUROLOGICAL BENEFIT
Which laboring patients get GBS prophylaxis?
-If GBS+ vaginal/rectal swab in the past 5 weeks
→ Routine screening from office visit (35-37 weeks), results in 48h
→ Inpatient NAAT test if available, results in ~30min?
-If she had GBS+ urine anytime in this pregnancy
-If she previously had a baby with GBS sepsis
-If she’s preterm AND GBS-unknown
-If ROM > 18h AND GBS-unknown
-If she’s febrile?
Group B Strep prophylaxis: why?
~30% women transiently colonized right now (tests valid 5 weeks at a time)
→ 50% transmission rate from colonized mother during vaginal delivery
→ 2% incidence of neonatal GBS sepsis within 1 week among those infected
→ 2% death rate in term infants; 22% death rate in preterm infants
→ less than non-GBS causes of sepsis that are not screened/prophylaxed
GBS prophylaxis regimens
2 first-line options:
- IV penicillin G, 5 million U x 1 dose + 2.5 million U q4h → delivery
- IV ampicillin, 2g x 1 dose + 1g q4h → delivery
PCN allergic:
-Low risk of anaphylaxis: IV cefazolin 2g x 1 dose + 1g q8h → delivery
-High risk of anaphylaxis: IV clindamycin 900mg q8h → delivery
(or if potential for clinda resistance, give vancomycin)
Choose your adventure: cephalic or not?
Vaginal breech delivery possible in some cases, but often riskier than cephalic deliveries. Transverse presentation must be delivered by cesarean.
On bedside ultrasound assessment of fetal position, you find a singleton fetus…
Baby is cephalic
(= by far, most common fetal presentation)
You anticipate vaginal delivery. She now has IV fluids and is being seen by anesthesia for epidural analgesia
How often do you need to check in on her? What things are you checking, and why?
Continue, or consider the non-cephalic scenarios
Tried External Cephalic Version?
>36 weeks but before active labor, attempt ECV of breech or transverse -presenting fetus to decrease risks of cesarean (or vaginal breech delivery)
→ Before 36 weeks, fetus can easily change position
Perform in OR with regional anesthesia & fetal monitoring (in case manipulations cause placental/cord accidents necessitating emergent cesarean delivery)
Vaginal breech extraction
Acceptable conditions for planned vaginal breech delivery:
-fetal weight 10th-90th %-ile for gestational age, per U/S
-fetal head flexed, per U/S
-no prior uterine scar
-adequate maternal pelvis, evidenced by CT and/or normally progressing labor
-complete or frank breech presentation (i.e. not footling!)
-experienced & readily available obstetrician
-1:1 nursing
Incomplete breech should be considered dangerous to deliver vaginally
Vaginal breech delivery: method
(Back to cephalic scenario, or skip to analgesia)
Neuraxial analgesia
-Bupivacaine or similar local anesthetic, +/- opioid
-Spinal (single injection), epidural (continuous), or combo.
-Used in ~ ⅔ of all births in America; more effective for pain than systemic opioids
-Laboring patient’s request is sufficient indication
-Absolute contraindications:
-Refractory hypotension
-Bleeding risk: coagulopathy, thrombocytopenia, or LMWH <12h ago
-Infection risk: untreated bacteremia, or skin infection at needle placement site
-Mass lesion causing increased intracranial pressure
-Relative contraindications: aortic stenosis, pulmonary HTN, neurological disorders
-Relieves labor pain from uterine contraction & cervical dilation; anesthetizes for cesarean or operative vaginal delivery, up to T4 or T10 levels respectively
-Risks:
-Hypotension (up to 31% w/epidural or 67% w/spinal)
-Pruritus from opioid (up to 26% w/epidural or 85% w/spinal)
-Inadequate pain relief from epidural (up to 15%)
-Fever (up to 19% of nulliparas)
-Fetal heart decelerations (8%; transient)
Problem 6: Interpret this tracing!
It’s about 2h after admission. She now has her epidural. You see this tracing:
(decel > 2min, minimal variability)
Read the handout (category II FHT mgmt), then describe your management with a brief explanation of your reasoning. Include resuscitative measures and reassessment in the order you or an assistant would perform them.
After 10 minutes...
Her cervix is still at 5cm.
What do you do if you see this tracing?
(moderate variability, rate back in normal range near baseline)
What do you do if you see this tracing?
(persistently brady with minimal variability)
Baby can tolerate more labor
… but is this normal progress?
Read ACOG’s Obstetric Care Consensus Statement #1, then fill in the blanks:
You should not diagnose active-phase arrest unless patient is already beyond 6 cm dilated when cervical change ceases. By the older definition, the cutoff used to be a lack of change after 4 cm.
(Continue to our labor management protocol, or go back to consider the other tracing)
Category III fetal heart tracing
You have already attempted resuscitative measures
This is ominous and an indication for emergent delivery
→ Which delivery route is quickest? Since she is 5cm dilated, vaginal delivery would take much longer than cesarean - so cesarean is the correct choice in this case
(Proceed to cesarean delivery, or skip to labor management protocol)
Cesarean delivery
Recap of indications
Absolute: placenta previa, vasa previa, uterine rupture, any previous active segment scar, 3+ lower segment incisions
Relative: Fetal distress, malpresentation, macrosomia, dystocia, triplets or more
Recommended techniques
Antibiotics <1h before skin incision
Transverse skin incision; blunt subQ & rectus dissection
Transverse incision of lower uterine segment, blunt cephalocaudal expansion
Spontaneous placental delivery, uterine exteriorization, 1-layer running locked closure
Non-closure of peritoneum, mass closure of abdominal wall, suture for skin, no drains!
Early postop diet
Our suggested labor management protocol
Problem 7: Interpret this indeterminate tracing!
You decide to start high- dose pitocin. After about 2 hours of augmentation you see the following tracing:
(moderate variability; accels; significant variable decels with >50% of ctx; ~5 ctx/10min)
Please describe what you see.
Her cervix is dilated to 6cm (+1cm/2h). Please explain briefly in writing what you want to do.
What do you do 15min later…
(good variability, accels, much fewer decels, ~5ctx/10min)
(same pattern of good variability but recurrent variable decels)
(minimal/absent variability, recurrent variable decels)
Continue augmentation
2 hours later, she is 8cm/80/+1.
1 hour after that, she reports feeling the urge to push; you re-examine to find her cervix completely dilated and effaced.
You are able to palpate the fontanelles, and determine baby to be LOA, still at +1 station.
(Continue, or consider the other tracings)
Problem 8: Recurrent variable decels
Variable decels accompanied by moderate baseline variability are not concerning for hypoxia, but may eventually lead to decreased variability (which is concerning for hypoxia) depending on the cause.
Fill in the blanks! Recall that these are thought to be caused by _________, or _________. Thus, __________ is an intervention that may target the cause of variable decels in particular, reducing the chance of fetal hypoxia later.
Alternatively, during descent, variable decels may be caused by nuchal cords that are being stretched.
(Continue, or go back to the other possible tracings in this scenario)
Cephalic fetal positions
Most commonly vertex (chin to chest) and OA
Other presentations (head extended → brow or face first; facing OT or OP) from failed cardinal movements of labor (e.g. flexion, rotation)
→ If baby not OA, try correcting with manual rotation to ease subsequent labor & reduce chance of cesarean or operative delivery. Higher station = easier to rotate.
→ Skull sutures can be difficult to differentiate if significant scalp swelling
→ Brow/face presentation: do not try to flex head! However, may manually rotate chin anteriorly - vaginal delivery impossible if face presentation with chin posterior (head diameter at that angle is usually too wide to fit through pelvis)
-Make sure you know it’s not breech! It’s possible to feel an orifice and think it’s the mouth when it’s actually the anus :(
Second stage
You encourage her to push with each contraction.
How long should she continue before you intervene?
→ Per ACOG Obstetric Consensus #1: allow up to 4h for delivery once completely dilated before diagnosing protraction/arrest and intervening
→ Unless superceding issues, i.e. fetal distress
→ For nulliparous w/epidural. Subtract 1 hour each for multiparity & lack of epidural
Choose your adventure: 2nd stage
You help her by pushing downward and laterally in posterior vagina with 2 fingers from each hand.
After nearly 4h of complete dilation…
Spontaneous vaginal delivery: Protect the perineum!
Watch this excellent simulation (in Danish)! https://youtu.be/X9_FP3fG8XM
→ this guards against explosive delivery, reducing perineal trauma
(Continue, or go back to consider prolonged second-stage labor)
Abnormal second stage
Our patient is nulliparous, with an epidural, and completely dilated cervix for over 4h. Fetus has progressed in station during that time.
Before you click ahead, please consider: What is your diagnosis? When will you intervene? What will your intervention(s) be? Why do you choose those interventions over others?
Interventions
If baby is not OA, you can attempt to manually rotate head (this is more difficult at lower station)
→ success may permit spontaneous vaginal delivery
→ success will also increase chance of successful operative vaginal delivery
Forceps or vacuum may help avoid Cesarean
→ For either instrument, must meet prereqs:
-Cesarean readily available if necessary (i.e. traction does not produce descent)
-Cervix is fully dilated, membranes ruptured, head engaged
-Mother in proper position, adequately anesthetized, with bladder and rectum emptied
-Most experienced physician has confirmed fetal position & station as well as its relationship to adequate maternal pelvis
Forceps or vacuum?
Forceps
-May allow rotation of fetal head to OA (at risk of causing spinal cord injury)
-Higher risk of soft-tissue injury to mother
-Higher risk of facial injury or skull fracture
Vacuum
-Favored 4:1 over forceps in the U.S.
-Harder to position correctly if baby head asynclitic or scalp swollen
-More likely to fail (= 3 pop-offs), especially if poor descent & mother is exhausted
-Higher risk subgaleal hemorrhage & shock, esp. if traction applied without descent
-If you’re only skilled using one instrument, pick that one!
-Once either instrument is properly applied and fails to produce descent, do not switch to the other instrument! That confers higher risks to fetus. Just go to cesarean!
-Low-level evidence finds no difference between vacuum vs. forceps in outcomes of fetal intracranial hemorrhage, or long-term maternal bowel/bladder dysfunction
Operative vaginal delivery
We will not go further into forceps or vacuum technique with this elective. You will likely be trained by obstetricians with a stronger preference for one instrument vs the other, and develop your own preferences as well. We encourage you to become proficient in both, so that you can always choose the most suitable instrument based on the situation and use it safely.
Back to our case: you have chosen one of the instruments and applied it properly to the fetal head. Thankfully, the baby descends with traction, so you proceed to deliver the head.
Choose your adventure: shoulders
After head is delivered & restitutes, you pull downwards…
… the anterior shoulder emerges easily, followed by posterior shoulder when you pull up & out
Problem 9: Shoulder dystocia
= 60+ sec between head & body delivery
→ emergency; extra obstetrical maneuvers required
Incidence 0.3-3%; most occur in women with no risk factors
→ Please list at least 5 risk factors for shoulder dystocia
Managing dystocia: HELPERR
Call for HELP
ELEVATE LEGS (McRoberts)
Suprapubic PRESSURE
ENTER with entire hand
-Rotation (Rubin II/Wood’s)
-Posterior arm
REPEAT once
For more complete review, see http://www.obsimulation.com
What about episiotomies?
Abdominal rescue of shoulder dystocia
When maneuvers for vaginal delivery have been repeated twice (90 seconds total!) and failed, you will proceed to the OR.
→ Zavanelli requires manually replacing fetal head inside vagina (after mother is anesthetized), to perform cesarean delivery
→ Abdominal rescue requires hysterotomy to allow direct manipulation of fetal shoulders for vaginal delivery
Postpartum
Baby is vigorous. You hand her to mother, and prepare cut the cord and deliver the placenta.
Equivocal recommendations on delayed cord clamping in term infants (see ACOG Committee Opinion #543)
Active management shortens 3rd stage of labor & helps prevent postpartum hemorrhage
-Controlled traction on cord with one hand
-Push up against uterus through abdomen with other hand (Brandt maneuver)
-IV pitocin after anterior shoulder delivered
Check for lacerations!
May allow 1st degree tear to heal without sutures if skin edges close enough
Continuous suture to reapproximate muscle in 2nd degree tear
Surgical repair with follow-up at 6-12 weeks for 3rd and 4th degree tears
Choose your adventure: “4th stage” of labor
This refers to the first 1-2 hours postpartum, during which the uterus involutes and expels any remaining contents. This is hastened by oxytocin (stimulated endogenously by breastfeeding or administered synthetically).
You have cleaned up and are ready to leave the room…
… your patient is resting comfortably, holding her infant.
… your patient begins bleeding briskly from the vagina.
Postpartum hemorrhage
Recently, redefined as >1L blood loss after delivery (vaginal or cesarean)
~1% of deliveries result in severe hemorrhage (= causing hemodynamic instability)
Top causes: Atony (~70%), trauma (~20%), retained tissue (~10%), coagulopathy (~1%)
PPH management
-Call for help!
-Start at uterus: massage; compress
-Lie her flat, give O2 (intubate if needed)
-Large bore IV x2 with crystalloids; check blood counts, clotting, cross-match 4-6U rbc’s
-Empty bladder
-Pitocin + misoprostol PR or methergine
-Reassess for uterine/vaginal/perineal trauma
-Explore uterus for retained tissue
-Surgery if bleeding persists (Next slide)
When is she ready to go home?
Discharge criteria include
-Maternal vitals stable
-Mother can independently ambulate, void and eat
-Pain sufficiently controlled without IV analgesics
-No signs of infection (endomyometrial, perineal, breast)
-Issues with breastfeeding have been addressed
-Plan for contraception established
-Necessary vaccinations administered
Usually 48h after vaginal delivery, or 72h after cesarean in uncomplicated cases
Sources
ACOG Obstetric Care Consensus #1…
Neonatal Encephalopathy and Neurologic Outcome, 2nd ed.
JAMA. 2014;312(11):1105-1113. doi:10.1001/jama.2014.11189
Verani JR, McGee L, Schrag SJ, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC). Prevention of perinatal group B streptococcal disease--revised guidelines from CDC, 2010. MMWR Recomm Rep. 2010 Nov 19;59(RR-10):1-36