Special features of general materno-foetal anaesthesia during foetoscopic spina bifida repair

BACKGROUND General anaesthesia during pregnancy requires close monitoring of both mother and foetus and therefore represents a special challenge. Little is known about its impact or its correct management for pregnant women and their foetuses. Therefore, foetoscopic spina bifida repair employing general materno-foetal anaesthesia offers a great opportunity to investigate and further characterise its effects on mother and foetus that would otherwise remain undetermined. OBJECTIVES To evaluate our standard protocol for the anaesthetic management of foetal spina bifida repair with respect to maternal and foetal haemodynamics. DESIGN A retrospective cohort study. SETTING Single-centre study, University Medical Centre Mannheim, University of Heidelberg. PATIENTS We analysed 70 patients in this study. All interventions for foetal spina bifida repair between June 2018 and December 2022 were eligible for this study. MAIN OUTCOME MEASURES During foetoscopic spina bifida surgery, we evaluated materno-foetal haemodynamics and characteristics and safety of our anaesthetic standard protocol. Blood gas analyses (BGAs) and pulse contour cardiac output (PiCCO) analyses were performed regularly. Transabdominal sonography including Doppler analyses of the umbilical artery as a proxy for foetoplacental haemodynamics were performed at predefined time points throughout the procedure. RESULTS During the course of anaesthesia, a significant drop of both median [IQR] maternal base excess and pH were observed: -3.6 [-2.6 to -4.6] vs. -7.1 [-5.3 to -8.25] and 7.35 [7.33 to 7.37] vs. 7.32 [7.29 to 7.35], respectively. PiCCO analyses suggested an increasing need for fluid therapy resulting in a significant increase in the median [IQR] extravascular lung water index, 7 [7 to 8] vs. 8 [7 to 9]. The pulsatility index of the umbilical artery increased during the course of surgery. Despite their significance, these changes did not represent clinically meaningful differences. CONCLUSIONS General materno-foetal anaesthesia could be performed without meaningful effects on materno-foetal haemodynamics and maternal blood gases with the appropriate materno-foetal monitoring in a large number of foetoscopic surgical procedures. There is growing need to enable closer foetal monitoring with respect to depth of anaesthesia, vital signs and pain perception.