Poster Session I Thursday, February 1 • 10:30 AM - 12:00 PM • Trinity Exhibit Hall| Volume 218, ISSUE 1, SUPPLEMENT , S122, January 01, 2018

179: The misdiagnosis of amniotic fluid embolism


      Amniotic fluid embolism (AFE) remains a leading cause of maternal mortality. Historically, case definitions along with laboratory and pathologic analysis of suspected cases have been non-specific, leading to challenges in the diagnosis and management. Diagnostic criteria for the research reporting of AFE has recently been published to promote uniformity in data collection, refine the identification of clinical risk factors and improve treatment strategies (Clark, 2016). In collaboration with the AFE Foundation and Baylor College of Medicine, these criteria have been utilized to characterize and differentiate true AFE from non-AFE cases and to determine the diagnoses most commonly mistaken for AFE using this contemporary AFE registry.

      Study Design

      Charts of patients enrolled in the AFE registry between 2013 and 2017 were analyzed. Patients were categorized into having suffered an AFE using the current published diagnostic criteria recommended for the research reporting of AFE (Clark,2016). Indeterminate cases were defined as those whose records were incomplete or when reviewed, the diagnosis remained uncertain. The non-AFE group included those with hemodynamic collapse which, after careful record review, clearly was secondary to other defined causes.


      One hundred and forty-five patients were enrolled in the registry at the time of analysis, of which 115 charts were available for review. Of these, 68 (59%) were categorized as having suffered an AFE. Twenty-one (18%) were classified as indeterminate and 26 (23%) were non-AFE cases. Of the 26 women misclassified as having had an AFE, the most common diagnosis was hypovolemic shock secondary to postpartum hemorrhage (n=14, 53.8%), followed by anesthetic complications (n=4, 15.3%) and sepsis related cardiovascular collapse (n=2, 7.6%). Six women were misclassified as AFE but the exact etiology of morbidity and mortality remains unknown due to maternal deterioration remote from delivery or death occurred outside of a medical facility with limited records indicating other cause.


      Hypovolemic shock from uncontrolled postpartum hemorrhage was most commonly misclassified as AFE. Our data suggests that approximately 30% of patients diagnosed with AFE upon hospital discharge are misclassified when charts are critically reviewed and standardized criteria are used to define cases. (Moaddab,2017)