Prevention of maternal death: amniotic fluid embolism must be spotted early.(Obstetrics)

NEW YORK -- Early and aggressive management of amniotic fluid embolism is vital in preventing maternal death, Dr. George R. Saade said at an obstetrics symposium sponsored by Columbia University and New York Presbyterian Hospital.

Although rare, amniotic fluid embolism remains a major cause of maternal mortality when it does occur, said Dr. Saade, professor of obstetrics and gynecology at the University of Texas, Galveston.

The true incidence of amniotic fluid embolism is unknown. In published data, the proportion ranges from 1 in 8,000 to 1 in 83,000 deliveries. Although still high, maternal mortality for this condition appears to be declining: A recent study found a maternal death rate of 26.4%, compared with the previously reported 60%-80% (Obstet. Gynecol. 93[6]:973-77, 1999).

The cause is still being debated, but the prevailing theory is that the condition results from an anaphylactoid reaction rather than a direct vascular effect of the amniotic fluid, Dr. Saade said.

The classic presence of fetal squamous cells in the maternal circulation can occur even in the absence of amniotic fluid embolism and is therefore not sensitive or specific enough to establish a diagnosis.

The diagnosis of amniotic fluid embolism must be made clinically, based on recognition of its rapid and dramatic evolution from respiratory distress and cyanosis to hypotension/shock to cardiac collapse, disseminated intravascular coagulation, and hemorrhage. Fetal distress is often the first apparent manifestation.

However, there have also been cases in which coagulopathy was the initial manifestation, while the other signs remained subclinical until later.