Amniotic Fluid Embolism

Abstract

Amniotic fluid embolism is one of the most devastating complications in obstetrics. Intensivists are often called upon to co-manage cases of suspected amniotic fluid embolism with our colleagues in obstetrics and anesthesia, so familiarity with this condition is essential. Amniotic fluid embolism is characterized by the sudden onset of hypotension, hypoxia, and coagulopathy during, or immediately after, delivery. Although rare in an absolute sense, amniotic fluid embolism is identified as the leading cause of maternal mortality in many developed countries. Amniotic fluid embolism is thought to occur when amniotic fluid enters into the maternal systemic circulation through a breach in the maternal–fetal interface, leading to the release of inflammatory mediators and endogenous catecholamines that cause acute cor pulmonale and severe disseminated intravascular coagulation (DIC). The diagnosis of amniotic fluid embolism is a clinical diagnosis of exclusion; there is no gold-standard test or biomarker. The treatment is largely supportive. Despite prior reports of mortality rates exceeding 80%, current evidence supports a mortality rate of approximately 20%.