THROMBOEMBOLIC DISEASE OF PREGNANCY
Deep vein thrombosis (DVT) and pulmonary embolism (PE) are the leading causes of maternal morbidity and mortality in industrialized nations. Symptoms are similar to those seen in nonpregnant women. Evaluation for DVT should begin with ultrasound of the lower extremities. If there is a concern for PE initiate the evaluation with a chest radiograph. d-dimer may not be helpful to diagnose or exclude thromboembolic disease as levels increase throughout pregnancy. Consensus guidelines recommend obtaining a V/Q scan or CT pulmonary angiography next if the chest radiograph is nondiagnostic. DVT and PE are treated with unfractionated heparin or low-molecular-weight heparin. Do not use warfarin in pregnancy as it crosses the placenta, potentially causing fetal CNS abnormalities and embryopathies such as bone and cartilage abnormalities as well as nasal and limb hypoplasia.
The underlying causes of chest pain in pregnancy are similar to those of nonpregnant women. Some disorders, such as aortic dissection and cardiomyopathy, may be associated with pregnancy. Treat pregnant women with acute myocardial infarction with aspirin, heparin, and percutaneous intervention rather than thrombolytics. Treat congestive heart failure and pulmonary edema with standard modalities except for sodium nitroprusside. It should be avoided as it can cause thiocyanate and cyanide accumulation in the fetus.
Chronic hypertension is defined as blood pressure at or above 140/90 mmHg prior to pregnancy, prior to 20 weeks’ gestation or lasting more than 12 weeks after delivery. These patients are at risk for abruption, preeclampsia, low birth weight, cesarean delivery, premature birth, and fetal demise.
Gestational hypertension is defined as blood pressure at or above 140/90 mmHg after 20 weeks or in the immediate postpartum period but without proteinuria.
Hypertension in pregnancy is defined as a systolic blood pressure ≥140 mmHg or diastolic ≥90 mmHg on two occasions at least 4 hours apart in a woman who was normotensive prior to 20 weeks’ gestation.
Preeclampsia is characterized by hypertension, greater than 140/90 mmHg, on two occasions at least 4 hours apart and proteinuria ≥300 mg in 24 hours in patients at 20 weeks’ gestation until 4 to 6 weeks after delivery. In the absence of proteinuria, thrombocytopenia with platelet count less than 100,000, elevation of liver enzymes twice normal, new renal insufficiency with a creatinine of 1.1 or a doubling of serum creatinine, pulmonary edema, or new-onset mental status disturbances or visual disturbances can be used to make the diagnosis of preeclampsia. Edema may or may not be present. Symptoms of severe preeclampsia reflect end-organ involvement and may include headache, visual disturbances, mental status changes, edema, oliguria, dyspnea due to pulmonary edema, and abdominal pain. Blood pressure in severe preeclampsia is typically elevated to 160/110 mmHg or more.