A 32-year-old woman in her 40th week of pregnancy suddenly collapses. She is hypotensive and tachycardic, but afebrile. Pulse oximetry reading is 91% on room air, and she bleeds profusely whenever the nurses stick her with a needle.
Amniotic fluid embolus-amniotic fluid embolus (afe) is the release of amniotic fluid into the maternal circulation during intense uterine contractions or uterine manipulation, or at areas of placental separation from the uterine deciduas basalis (abruptio placentae), triggering a rapidly fatal anaphylactoid-type maternal response. although afe most commonly occurs during labor, it can also occur after induced abortions and miscarriage and spontaneously during the second and third trimesters. afe should be suspected during the second or third trimester of pregnancy when a patient experiences sudden hypotension, hypoxia, and coagulopathy.
Half of the mortality occurs during the first 2 hours when vasospasm, release of vasoactive substances, and mechanical plugging of vessels, trigger abrupt cardiopulmonary collapse. acute respiratory distress syndrome (ards), disseminated intravascular coagulation, and left ventricular dysfunction can also develop. an initial seizure is seen in about 10% of patients. bleeding diathesis may be the initial sign in 10% to 15% of women.