Anaesthesia-related maternal mortality in low-income and middle-income countries: a systematic review and meta-analysis

Background: The risk factors contributing to maternal mortality from anaesthesia in low-income and middle-income countries and the burden of the problem have not been comprehensively studied up to now. We aimed to obtain precise estimates of anaesthesia-attributed deaths in pregnant women exposed to anaesthesia and to identify the factors linked to adverse outcomes in pregnant women exposed to anaesthesia in low-income and middle-income countries.

Methods: In this systematic review and meta-analysis, we searched major electronic databases from inception until Oct 1, 2015, for studies reporting risks of maternal death from anaesthesia in low-income and middle-income countries. Studies were included if they assessed maternal and perinatal outcomes in pregnant women exposed to anaesthesia for an obstetric procedure in countries categorised as low-income or middle-income by the World Bank. We excluded studies in high-income countries, those involving non-pregnant women, case reports, and studies published before 1990 to ensure that the estimates reflect the current burden of the condition. Two independent reviewers undertook quality assessment and data extraction. We computed odds ratios for risk factors and anaesthesia-related complications, and pooled them using a random effects model. This study is registered with PROSPERO, number CRD42015015805.

Findings: 44 studies (632,556 pregnancies) reported risks of death from anaesthesia in women who had an obstetric surgical procedure; 95 (32,149,636 pregnancies and 36,144 deaths) provided rates of anaesthesia-attributed deaths as a proportion of maternal deaths. The risk of death from anaesthesia in women undergoing obstetric procedures was 1·2 per 1000 women undergoing obstetric procedures (95% CI 0·8-1·7, I(2)=83%). Anaesthesia accounted for 2·8% (2·4-3·4, I(2)=75%) of all maternal deaths, 3·5% (2·9-4·3, I(2)=79%) of direct maternal deaths (ie, those that resulted from obstetric complications), and 13·8% (9·0-20·7, I(2)=84%) of deaths after caesarean section. Exposure to general anaesthesia increased the odds of maternal (odds ratio [OR] 3·3, 95% CI 1·2-9·0, I(2)=58%), and perinatal deaths (2·3, 1·2-4·1, I(2)=73%) compared with neuraxial anaesthesia. The rate of any maternal death was 9·8 per 1000 anaesthetics (5·2-15·7, I(2)=92%) when managed by non-physician anaesthetists compared with 5·2 per 1000 (0·9-12·6, I(2)=95%) when managed by physician anaesthetists.

Interpretation: The current international priority on strengthening health systems should address the risk factors such as general anaesthesia and rural setting for improving anaesthetic care in pregnant women.

Funding: Ammalife Charity and ELLY Appeal, Bart's Charity.