Amniotic Fluid Embolism (AFE) Background
Amniotic fluid embolism (AFE) is a rare obstetric emergency in which it is postulated that amniotic fluid, fetal cells, hair, or other debris enter the maternal circulation, causing cardiorespiratory collapse.
In 1941, Steiner and Luschbaugh described AFE for the first time after they found fetal debris in the pulmonary circulation of women who died during labor.
Current data from the National Amniotic Fluid Embolus Registry suggest that the process is more similar to anaphylaxis than to embolism, and the term anaphylactoid syndrome of pregnancy has been suggested because fetal tissue or amniotic fluid components are not universally found in women who present with signs and symptoms attributable to AFE.
The diagnosis of AFE has traditionally been made at autopsy when fetal squamous cells are found in the maternal pulmonary circulation; however, fetal squamous cells are commonly found in the circulation of laboring patients who do not develop the syndrome. In a patient who is critically ill, a sample obtained by aspiration of the distal port of a pulmonary artery catheter that contains fetal squamous cells is considered suggestive of but not diagnostic of AFE syndrome. The diagnosis is essentially one of exclusion based on clinical presentation. Other causes of hemodynamic instability should not be neglected.
For related information on pregnancy, see Medscape’s Pregnancy Resource Center.
