Eclampsia in the 21 ^st century

The reported incidence of eclampsia is 1.6-10 per 10,000 deliveries in developed countries, where as it is 50-151 per 10,000 deliveries in developing countries. In addition, low resource countries have substantially higher rates of maternal and perinatal mortalities and morbidities. This disparity in incidence and pregnancy outcomes maybe related to universal access to prenatal care, early detection of preeclampsia, timely delivery, and availability of health care resources in developed as compared to developing countries. Because of its infrequency in developed countries, many obstetric providers and maternity units have minimal to no experience in acute management of eclampsia and its complications. Therefore, clear protocols for prevention of eclampsia in those with severe preeclampsia and acute treatment of eclamptic seizures at all levels of health care are required for better maternal and neonatal outcomes. Eclamptic seizure will occur in 2% of women with preeclampsia with severe features who are not receiving magnesium sulfate, and in less than 0.6% in those receiving magnesium. The pathogenesis of an eclamptic seizure is not well understood, however blood brain barrier (BBB) disruption with passage of fluid, ions and plasma protein into the brain parenchyma remains the leading theory. New data suggest that BBB permeability may increase by circulating factors found in preeclamptic women plasma such as vascular endothelial growth factor and placental growth factor. The management of an eclamptic seizure will include supportive care to prevent serious maternal injury, magnesium sulfate for prevention of recurrent seizures and promoting delivery. While routine imagining following eclamptic seizure is not recommended, the classic finding is referred to as posterior reversible encephalopathy syndrome (PRES). The majority of patients with PRES will show complete resolution of the imaging finding within 1-2 weeks, but routine imaging follow up is unnecessary unless there are findings of intracranial hemorrhage, infraction or ongoing neurologic deficit. Eclampsia is associated with increased risk for maternal mortality and morbidity such as placental abruption, disseminated intravascular coagulation, pulmonary edema, aspiration pneumonia, cardiopulmonary arrest and acute renal failure. Furthermore, a history of eclamptic seizure is may be related to long-term cardiovascular risk and cognitive difficulties related to memory and concentration years after the index pregnancy. Finally, limited data suggest that placental growth factor levels in preeclamptic women are superior to clinical markers in prediction of adverse pregnancy outcomes. This data may be extrapolated to prediction of eclampsia in future studies. This summary of available evidence provides data and expert opinion on possible pathogenesis of eclampsia, imagining findings, differential diagnosis, and stepwise approach regarding management of eclampsia prior to delivery and during the postpartum, as well as current recommendations for prevention of eclamptic seizure in women with preeclampsia.

Keywords: abruption; angiogenic; cardiovascular; cerebral edema; convulsions; fetal death; fetal growth restriction; hypertensive disorder of pregnancy; including placental growth factor (PlGF); magnesium sulfate; maternal mortality; posterior reversible encephalopathy syndrome (PRES); seizures; severe maternal morbidity; soluble Endoglin; soluble fms-like tyrosine kinase-1 (sFlt-1); vascular endothelial growth factor (VEGF).