Severe Preeclampsia at 34 Weeks with a Prior Classical Cesarean
A 31-year-old G2P1 at 34 weeks 1 day presents with a severe headache and visual scotomata. Her prior pregnancy ended in a classical cesarean at 27 weeks for a placenta previa with hemorrhage. Current vitals: BP 168/112 on two readings 15 minutes apart, HR 88, RR 16, SpO2 98%. She has 3+ proteinuria on dipstick. Labs: platelets 88,000, AST 92, ALT 78, creatinine 1.1, uric acid elevated. Fetal tracing shows a baseline of 150 with minimal variability and one late deceleration. Ultrasound shows a singleton, cephalic, estimated weight 2,100 g, normal fluid. She is at a hospital with a level III nursery and 24-hour anesthesia.
1. What is your immediate management, and what is the timing and route of delivery?
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This is severe preeclampsia with severe features (BP ≥160/110, platelets <100,000, elevated transaminases, headache and visual symptoms) at 34 weeks with a nonreassuring fetal tracing. Delivery is indicated - she is at or beyond 34 weeks with severe features, and the fetal tracing is concerning.
Immediate steps:
- Magnesium sulfate for seizure prophylaxis - 4–6 g loading dose then 1–2 g/hour, with monitoring of reflexes, respiratory rate, and urine output.
- Antihypertensive therapy - labetalol, hydralazine, or nifedipine to bring BP below 160/110, with a goal of gradual reduction.
- Antenatal corticosteroids - betamethasone, though at 34 weeks the benefit window is narrow; give if delivery can be delayed 24–48 hours, but do not delay delivery for steroids if the mother or fetus is deteriorating.
- Fetal monitoring and preparation for delivery.
Route: she has a prior classical cesarean, which is a contraindication to labor and vaginal delivery because of the risk of uterine rupture. She requires cesarean delivery. The classical scar also means the cesarean should be planned with the understanding that the scar may be thin or involved, and the surgeon should be prepared for possible accreta or scar dehiscence. Delivery should occur promptly given the severe features and nonreassuring tracing.
2. During cesarean, the lower uterine segment is thin and the placenta is anterior. What is your concern, and how do you proceed?
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An anterior placenta with a thin lower uterine segment in a patient with a prior classical cesarean raises concern for placenta accreta spectrum, especially if the placenta is low-lying or previa. The prior classical scar and the thin segment increase the risk of accreta and of hemorrhage at delivery.
Proceed with caution:
- If accreta is suspected, the safest approach is to deliver the fetus and leave the placenta in place, then proceed to cesarean hysterectomy with the placenta in situ, rather than attempting manual removal, which can cause massive hemorrhage.
- Have blood products available and the anesthesia team prepared for massive transfusion.
- If the placenta separates easily and there is no accreta, proceed with routine delivery and inspect the scar for dehiscence.
- If accreta is confirmed and the patient desires future fertility, conservative management is generally not recommended with a classical scar because of the high risk of hemorrhage and rupture; hysterectomy is the definitive treatment.
Postoperative: monitor for hemorrhage, and counsel about the implications for future pregnancies - she would be at high risk for recurrence and should be counseled against future pregnancy or managed by a high-risk team.
3. She has a cesarean hysterectomy for accreta. Two days later she develops shortness of breath and tachycardia. How do you evaluate her?
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Postoperative shortness of breath and tachycardia after cesarean hysterectomy for accreta has a broad differential: pulmonary embolism, hemorrhage/anemia, infection, pulmonary edema (from fluid resuscitation or preeclampsia), and, less commonly, amniotic fluid embolism or myocardial infarction.
Evaluation:
- Vital signs, oxygen saturation, and physical exam.
- CBC, coagulation studies, and type and screen.
- Chest radiograph and ECG.
- If PE is suspected, CT pulmonary angiography (or V/Q scan if contrast is contraindicated).
- Consider lower extremity ultrasound for DVT.
Management: if PE is confirmed, start therapeutic anticoagulation (low-molecular-weight heparin or unfractionated heparin) unless there is active hemorrhage. If pulmonary edema is the cause, manage with diuresis and oxygen. If hemorrhage is the cause, transfuse. She is at elevated risk for VTE given the surgery, preeclampsia, and immobility, so a high index of suspicion is warranted. Do not dismiss the symptoms as anxiety.