Risk factors for fatality in amniotic fluid embolism: a systematic review and analysis of a data pool

Purpose: Investigating risk factors for amniotic fluid embolism (AFE)-induced fatality. Methods: A systematic review of cases of AFE available on PubMed, Scielo, Scopus and AJOL databases that occurred from 1990 to 2015 was carried out. After careful reading of titles, abstracts and full texts, case reports of AFE were reviewed. Risk factors for AFE were considered as independent variables in logistic regression models. The first model was built on the whole data pool. The second model was built on typical cases of AFE, according to the classical triad of symptoms (heart, lungs, coagulopathy). The dependent variable was fatality in both models. Results: 177 cases of AFE were assessed in the first model, while 121 typical cases of AFE were assessed in the second model. Among typical cases of AFE, only oxytocin infusion during labour increases the likelihood of death (odds ratio 2.890, 95% confidence interval 1.166–7.164, p = 0.022). No risk factors for fatality were found in the whole data pool. Conclusions: Further research on national registries should focus on the behaviour of oxytocin infusion during labour in AFE cases.