Headache, Hypertension, and Crackles at 34 Weeks
A 33-year-old woman, gravida 2 para 1, at 34 weeks and 2 days gestation presents with a severe frontal headache and right upper quadrant pain for six hours. Blood pressure is 178/112 mmHg, and repeats at 176/110 mmHg. Respiratory rate 28, SpO2 88% on room air, with crackles to the mid-scapular line bilaterally. Platelets 82,000/microliter, AST 210 U/L, creatinine 1.3 mg/dL, urine output 20 mL/hour, urine protein 3+. Deep tendon reflexes are brisk with two beats of clonus. The fetal heart tracing shows a baseline of 150 beats per minute with minimal variability. She has received no medications yet.
1. Set your priorities for the first 30 minutes. What goes first, magnesium or antihypertensive, and to what target?
Read the worked answer
Both, started simultaneously by two people - but understand that they do different jobs.
Magnesium sulfate is seizure prophylaxis, not a blood pressure drug. Load 4–6 g IV over 15–20 minutes, then infuse 1–2 g/hour. This is the intervention that prevents eclampsia, and it should not be delayed while blood pressure is being negotiated. Give it slowly and watch the pressure - magnesium causes vasodilation and can drop her further.
Antihypertensive therapy treats the pressure, and the pressure is what causes her headache and her stroke risk. Options: labetalol 20 mg IV, repeated every 10 minutes and escalated to 40–80 mg; hydralazine 5–10 mg IV repeated every 20 minutes; or nifedipine 10 mg orally. Target systolic below 160 and diastolic below 110, and many would aim for 130–150 over 80–100. Do not normalize the pressure aggressively - a precipitous drop compromises uteroplacental perfusion in a patient who is already chronically vasoconstricted.
Also in the first 30 minutes: oxygen to keep her saturation up, continuous fetal monitoring, large-bore access, a Foley catheter to measure output, and notification of obstetrics and anesthesia. Type and screen, coagulation studies, and a hemolysis panel.
The order in practice: magnesium hanging and the first antihypertensive dose given within minutes of each other, with delivery as the definitive therapy that follows. Do not let the magnesium infusion delay the blood pressure treatment, and do not let the blood pressure treatment delay magnesium.
2. She is oliguric with 20 mL/hour and has bilateral crackles. Is she volume depleted? How much fluid do you give, and is there a role for diuresis?
Read the worked answer
She is not simply dry, and the reflex to give boluses is the error to avoid here.
Preeclampsia is a disease of endothelial injury with increased capillary permeability, low oncotic pressure from proteinuria, and vasoconstriction. Fluid moves out of the intravascular space into the interstitium - which is why she has pulmonary crackles and edema while at the same time having a contracted intravascular volume and oliguria. That combination is exactly why indiscriminate crystalloid makes preeclamptic pulmonary edema worse rather than better.
Practical approach:
- Restrict maintenance fluids to roughly 80 mL/hour, or about 1 mL/kg/hour. No boluses unless there is a specific indication such as hemorrhage or pre-load-dependent hypotension.
- If she is genuinely hypoperfused, 250 mL of crystalloid over 20–30 minutes with reassessment of the lungs, not 2 L on autopilot.
- Diuresis has a role once the blood pressure is controlled and magnesium is running. Furosemide 20–40 mg IV is appropriate for pulmonary edema with oliguria, particularly postpartum, and it often produces a brisk response. Give it with the understanding that over-diuresis can worsen placental perfusion - monitor the fetus and the urine output together.
- Remember that magnesium is renally cleared. With a creatinine of 1.3 and 20 mL/hour of urine, reduce the infusion rate, check magnesium levels, and monitor reflexes, respiratory rate, and urine output hourly. Calcium gluconate 1 g IV is the antidote for toxicity.
- Consider bedside echocardiography or central monitoring if the picture stays ambiguous; the clinical exam alone is unreliable in this population.
3. When do you deliver, by what route, and how do the platelet count of 82,000 and the gestational age of 34 weeks and 2 days change your planning?
Read the worked answer
Delivery is the definitive treatment, and with severe features plus pulmonary edema at 34 weeks and 2 days, it should happen now - not after a steroid course and not after a trial of medical therapy.
Timing: severe preeclampsia at or beyond 34 weeks is delivered. Antenatal corticosteroids have a modest evidence base between 34 and 37 weeks for fetal lung maturity, but they must never delay delivery for a mother with pulmonary edema, a pressure of 178/112, and a falling platelet count. If she stabilizes quickly and delivery can be arranged within 48 hours, steroids can be given concurrently; the obstetric team owns that decision, and the emergency physician should not be the one delaying for it.
Route: cesarean delivery is likely given the fetal tracing with minimal variability and an unfavorable cervix, but the decision belongs to obstetrics. Vaginal delivery is not contraindicated in severe preeclampsia. What matters from the emergency department is that she gets to the operating room or labor room with a controlled blood pressure and magnesium running.
The platelet count of 82,000 matters most for anesthesia. Neuraxial anesthesia is generally avoided below 70,000–80,000 because of epidural hematoma risk; at 82,000 she is borderline, and most anesthesiologists would want a repeat count and a documented trend before placing an epidural. The count can fall quickly in HELLP syndrome. She may need general anesthesia, which carries its own risks in a hypertensive pregnant patient.
Also: type and crossmatch, notify blood bank for possible platelet transfusion, and have the obstetric and anesthesia teams at the bedside before she leaves the emergency department.
What not to do: do not wait for the platelets to recover, do not treat the hypertension to a normal blood pressure, and do not let the fetal tracing be the only reason for urgency - the mother is the sicker patient.