Predictor of mortality in patients with amniotic fluid embolism

Abstract

The purpose of this study was to evaluate the possibility of establishing predictors of mortality in women with amniotic fluid embolism. Our previous report identified eight factors associated with amniotic fluid embolism (AFE) fatality: dyspnea, cardiac arrest, loss of consciousness, serum sialyl Tn greater than 47 U/mL, serum interleukin-8 greater than 100 pg/mL, vaginal delivery, multiparity and term delivery. The ratio of the number of positive fatal factors to the number of possible fatal factors in the same case was calculated as the abundance ratio, which was used because information regarding all eight factors was not retrievable for all the patients at the time of registration. The patient group was divided into four quartiles based on this abundance ratio, and the mortality rate in each quartile was compared with the overall mortality rate among the 130 patients with AFE enrolled between 1992 and 2006. The validity of this approach was confirmed in another dataset from a cohort of 38 patients with AFE in 2007. A statistically significant positive correlation was observed between the abundance ratio and the mortality in each quartile (P<0.01) for the patients with AFE enrolled between 1992 and 2006. This result was also found in the AFE patients enrolled in 2007 (P<0.05). Thus, an increased in the abundance ratio of the eight fatal factors resulted in an increased case fatality rate. These data suggested that the abundance ratio of fatal factors may be a useful predictor of mortality and therefore may be expected to improve prognostic accuracy in the future.