122 Obstetrics and Gynecology Board Review •••
❍ What is the optimal mode of delivery for mild preeclampsia?
Vaginal delivery.
❍ What is the optimal mode of delivery for severe preeclampsia?
Mode of delivery should be individualized with some recommending a scheduled cesarean delivery for pregnancies
at <30 weeks with a low Bishop score.
❍ What is the preferred method of anesthesia?
For preeclampsia and eclampsia the preferred method is regional anesthesia. This is contraindicated in the presence
of coagulopathy or severe thrombocytopenia (platelet count <50,000/mm^3 ).
❍ When does the blood pressure usually normalize?
Within the first week postpartum for gestational hypertension and within 2 weeks for preeclampsia
❍ Describe the classic eclamptic seizure.
Generalized tonic-clonic. Usually begins with facial twitching, followed after a few seconds by a phase of
generalized muscular contraction for 15 to 20 seconds. During the clonic phase, which may last about a minute,
all the muscles contract and relax alternately, usually starting at the jaws and the eyelids. The movements then
gradually subside, becoming smaller and less frequent until the woman eventually lies motionless.
❍ How should eclampsia be managed?
The first steps will include supportive care, maintaining an open airway and maternal oxygenation (supply oxygen
at 8 to 10 L/min). Magnesium sulfate (IV or IM) should be used to control convulsions and prevent recurrence.
Antihypertensive medications should be used for diastolic blood pressure of 105 to 110 mmHg or higher. Delivery
should be done in a timely fashion.
❍ What is the regimen of magnesium IV?
Loading dose of 4 to 6 g over 15 to 20 minutes, followed by maintenance of 2 g/h. The magnesium level
is measured every 4 to 6 h to adjust the level to 4.8 to 8.4 mg/dL.
❍ When should magnesium sulfate be discontinued?
Usually 24 hours after delivery or after the onset of convulsions. A randomized controlled trial published in 2006
(Ehrenberg & Mercer, 2006) concluded that for mild preeclampsia discontinuation of magnesium 12 hours after
delivery was associated with infrequent disease progression and a clinical course similar to that with 24-hour
therapy.
❍ How is magnesium cleared?
Renal excretion.
❍ What is the main side effect of magnesium?
Flushing.
❍ At what level, do the patellar reflexes disappear?
9.6 to 12 mg/dL.