Amniotic fluid embolism: update and review

This article reviews our current understanding of amniotic fluid embolism (AFE), specifically the pathogenesis, treatment strategies, potential diagnostic tests and future therapeutic interventions for AFE.

The incidence and case mortality of AFE varies widely because of heterogeneous diagnostic criteria and varying reporting mechanisms across the world. Amniotic fluid embolism is thought to be caused by abnormal activation of immunologic mechanisms following entry of fetal antigens into maternal circulation. Mast cell degranulation and complement activation may play a role in this anaphylactoid or systemic inflammatory response syndrome. Development of serum biomarkers and immune-histochemical staining techniques to aid diagnosis and develop treatments are under development and evaluation. Treatment of AFE is supportive and directed at treating cardiovascular, pulmonary, and coagulation derangements. Treatment for coagulopathy (fresh frozen plasma, cryoprecipitate/fibrinogen concentrate, and antifibrinolytics) should be initiated promptly. Recombinant factor VIIa may lead to increased mortality and should not routinely be used. C1 esterase inhibitors may be a potential therapeutic option.

AFE is a devastating obstetric complication that requires early and aggressive intervention with optimal cardiopulmonary resuscitation, as well as hemorrhage and coagulopathy management. Biomarkers offer promise to aid the diagnosis of AFE, and immunomodulation may provide future therapeutic interventions to treat this lethal condition.