Amniotic fluid embolism: 10-year retrospective study in a level III maternity hospital

Abstract

Objective: To provide updated data on amniotic fluid embolism (AFE) based on our population over a 10 year period, and to propose steps for improving current practice.

Study design: Retrospective study carried out in the Department of Gynaecology and Obstetrics at the Strasbourg University Teaching Hospital between 1 January 2000 and 31 December 2010. Dossiers of patients with AFE were identified using medical information system programme (MISP) coding and cross-checked with the pathology reports (hysterectomy, post-mortem examination).

Results: Eleven dossiers were found (0.28/1000). Eight cases (73%) of AFE occurred during labour, two (18%) in the post-partum period and one (9%) outside of parturition. Induction was initiated in four patients (45%) and labour sustained with oxytocin in 9 patients (90%). Acute circulatory collapse with cardio-respiratory arrest (CRA) was the herald symptom of AFE in 2 patients, and secondary cardio-respiratory arrest occurred rapidly in 6 patients (55%) following a relatively non-indicative prodromal phase. Disseminated intravascular coagulopathy (DIC) was observed in 10 cases (91%) and massive transfusion was necessary in all patients. Seven haemostatic hysterectomies (63%) were performed, with secondary arterial embolisation in 2 cases (22%). Although all patients presented a clinical picture of AFE, confirmation through histology or laboratory test results was forthcoming in only 7 cases (63%). Three patients died (27%). When AFE occurred during labour, 8 fetuses (75%) received intensive care support. In all, 11 newborns survived (85%). Their pH was less than 7.00 in 3 cases (27%) and 4 fetuses (36%) had an Apgar score of less than 5 at 5 minutes of life.

Conclusion: AFE is a rare but extremely serious disease. Some risk factors for AFE have been identified but they do not allow its occurrence to be predicted. The diagnosis may be supported by specific laboratory test results but only a post-mortem examination provides a pathognomonic diagnosis: unfortunately it is always retrospective. Obstetrical and intensive care management is complex and must be adapted to the situation bearing in mind the significant risk of haemorrhage and DIC. Hysterectomy must be performed if there is the least doubt.

Keywords: Amniotic fluid embolism; Delivery haemorrhage; Fetal morbidity and mortality; Maternal morbidity and mortality.