Mode of anaesthetic for category 1 caesarean sections and neonatal outcomes

Birth by emergency caesarean section (CS) is common and often considered urgent (category 1). In the UK, over half of all category 1 CS are performed under general anaesthesia (GA). In this setting, little is known about the effect of the mode of anaesthesia on the neonate.

A retrospective cohort study was performed using routinely collected de-identified data from Mater Health Services, Brisbane, Australia. The data set included 533 term babies born by category 1 CS for presumed fetal compromise between 2008 and 2011. Bivariate and multivariate analyses were undertaken.

The outcomes of 81 babies born by GA CS were compared with 452 by CS under regional anaesthesia (RA). Compared with a category 1 CS under RA, the decision-to-delivery interval for a GA CS was almost eight minutes faster (24.7 vs 32.6 minutes; P < 0.001). When adjusted for confounders, babies born by category 1 GA CS were significantly more likely to have an Apgar score < 7 at five minutes (aOR 6.89; 95%CI 1.79-26.55; P = 0.005), to require Neopuff or bag/mask ventilation for > 60 seconds (aOR 2.34; 95%CI 1.13-4.84; P = 0.022) and to be admitted to a neonatal intensive care nursery (aOR 2.24; 95%CI 1.16-4.31; P = 0.016).

General anaesthesia was associated with short-term neonatal morbidity of term babies born by category 1 CS for presumed fetal compromise, despite enabling a more rapid delivery of the baby. These data should help inform the discussion between anaesthetist and obstetrician, in balancing the risks and benefits of the mode of anaesthesia.