Obstetrics and Gynecology: Pregnancy Physiology, Hypertension, and Emergencies
OB/GYN: pregnancy changes the baseline
Pregnancy alters normal physiology: plasma volume rises, blood pressure often falls early and rises later, and heart rate increases. High-yield concepts include prenatal care, ectopic pregnancy, hypertensive disorders, gestational and preexisting diabetes, labor assessment, postpartum hemorrhage, contraception, STI management, and menopause. In early pregnancy with pain or bleeding, obtain blood type and Rh, quantitative hCG, and ultrasound; ectopic pregnancy is the diagnosis not to miss. In preeclampsia, hypertension after 20 weeks plus proteinuria or end-organ dysfunction defines disease; severe features include severe-range blood pressure, headache, visual changes, RUQ pain, thrombocytopenia, renal insufficiency, and pulmonary edema.
Traps
Do not diagnose gestational hypertension if severe features or proteinuria are present. Do not give ACE inhibitors or warfarin in pregnancy. Magnesium sulfate prevents and treats eclampsia; monitor reflexes, respiratory rate, and urine output, and use calcium gluconate for toxicity. Postpartum hemorrhage is often uterine atony; start uterotonics and massage while evaluating for retained placenta, laceration, and coagulopathy.
Worked rule
At ≥34 weeks with severe preeclampsia, delivery is generally indicated after stabilization with magnesium sulfate and antihypertensives. Before 34 weeks, steroids and magnesium are given, and delivery is delayed if maternal and fetal status allow.