Effect of different mechanical ventilation modes on cerebral blood flow during thoracoscopic surgery in neonates: A randomised controlled trial

Abstract

Infants exposed to major surgery are at risk of injuries to the immature brain because of reduced arterial oxygen saturation. This study compared the effect of volume-controlled ventilation (VCV) versus pressure-controlled ventilation (PCV) on cerebral oxygenation in neonates subjected to repair of tracheoesophageal fistula (TEF) under video-assisted thoracoscopic surgery (VATS). This randomised controlled study included 30 full-term neonates scheduled for VATS for managing TEF under general anaesthesia. They were randomised to either VC group (n = 15), who received VCV, or PC group (n = 15), who received PCV. Cerebral oxygenation (rScO2) was monitored throughout the surgery with documentation of episodes of cerebral desaturation. Peripheral oxygen saturation, partial pressure of carbon dioxide (PaCO2), and end-tidal carbon dioxide were recorded at baseline, after induction of anaesthesia, and every 30 min till the end of the surgery. rScO2 was significantly higher in the PC group than the VC group at baseline and was significantly higher in the VC group after 15 min (P = 0.041). Later, it was comparable in both the groups up to 60 min after starting the surgery. Cerebral desaturation was significantly more common in the PC group (80%) compared to VC group (33.3%) (P = 0.010). PC group required higher fraction of inspired oxygen and positive end-expiratory pressure to prevent cerebral desaturation. PaCO2 was significantly higher in the PC group than the VC group at 30 and 60 min (P = 0.005 and 0.029). VCV is safer than PCV for cerebral oxygenation during VATS in neonates.