Chapter 219 Pre-Eclampsia and Eclampsia (Toxemia of Pregnancy)
INTRODUCTION
Description: Pre-eclampsia is a pregnancy-specific syndrome (occurring after 20 weeks of gestation) of reduced organ perfusion, vasospasm, and endothelial activation characterized by hypertension, proteinuria, and other symptoms. Pregnancy can induce hypertension or aggravate existing hypertension. Edema and proteinuria (one or both) are characteristic pregnancy-induced changes. If pre-eclampsia is untreated, convulsions (eclampsia) may occur. Chronic hypertension may be worsened by or superimposed on pregnancy-induced changes. Severe cases may include hemolysis, elevated liver enzymes, and low platelet counts (HELLP syndrome; occurs in up to 20% of severe pre-eclampsia cases).
Prevalence: Five to eight percent of all births, 250,000 cases per year, result in 150 maternal deaths (18%) and 3000 fetal deaths per year. (Overall, hypertensive disease of some type occurs in approximately 12% to 22% of pregnancies, and it is directly responsible for 17.6% of maternal deaths in the United States.)
ETIOLOGY AND PATHOGENESIS
Causes: Unknown, genetic, endocrine/metabolic (including altered prostaglandin production), uteroplacental ischemia, immunologic all proposed.
CLINICAL CHARACTERISTICS
DIAGNOSTIC APPROACH
Workup and Evaluation
Laboratory: Liver and renal function studies (enzymes, renal clearance, 24-hour urinary protein measurement).
Special Tests: Assessment of fetal lung maturation may be performed, but if maternal disease is severe, management is based on maternal factors and not fetal maturation. Invasive hemodynamic monitoring may be required for patients with the most severe cases.
