Pre-eclampsia and eclampsia

Abstract

LTHOUGH pre-eclampsia and eclampsia affect only a small proportion of all pregnancies, they account for substantial obstetric morbidity and mortality.l2 Pre-eclampsia affects approximately 6% to 8% of all pregnancies, whereas eclampsia has an incidence of 1/1,000 to 1/2,000 deliveries in the United States. However, hypertension during pregnancy is responsible for up to 19% of maternal deaths in the United States. Most maternal deaths in pre-eclamptic women occur from either cerebral hemorrhage or adult respiratory distress syndrome. These complications are usually related to substandard care, the most common factor being a delay in treating the disease aggressively. Other lapses in care include poorly controlled hypertension, delayed delivery to allow fetal maturity, neglect of worsening symptoms, and inadequate postpartum management. Inadequate control of hypertension with subsequent cerebral hemorrhage remains a common, preventable cause of maternal death. Inadequate prophylaxis and treatment of eclamptic seizures is also a common contributor to maternal death. Although the exact etiology of pre-eclampsia is unknown, several factors predispose to preeclampsia, including nulliparity (85% of cases), African-American race, history of previous preeclampsia, family history of pre-eclampsia, obesity, lupus erythematosus, protein S and protein C deficiency, chronic hypertension, renal disease, insulin-dependent diabetes, and conditions associated with rapid uterine growth (eg, macrosomia). Hypertension is commonly an isolated finding with no further complications. However, some women also develop renal, central nervous system, cardiovascular, and/or hematologic dysfunction. The American College of Obstetricians and Gynecologists (ACOG) categorize hypertensive disorders of pregnancy as follows: (1) pregnancy induced hypertension~women who develop hypertension during pregnancy; pre-eclampsia-hypertensive women who also develo p proteinuria; eclampsia--preeclamptic women who also experience seizures/or coma; HELLP syndrome--thrombocytopenia with evidence of hemolysis and increased liver enzymes in pre-eclamptic women; (2) chronic hypertension--hypertension that precedes pregnancy; and (3) chronic hypertension with superimposed pre-eclampsia/eclampsia. With regard to anesthetic management, improper selection of anesthesia and inadequate control of hypertension during anesthesia are the most common reasons for morbidity and mortality. To minimize the possibility of a poor outcome, anesthesiologists must understand pre-eclampsia and eclampsia with their complex pathophysiology and variable presentation and have an optimal plan for anesthetic management.