Efficacy of a lung recruitment manoeuvre in children undergoing general anaesthesia with a supraglottic airway.

Abstract

Lung atelectasis is a well-recognised consequence of general anaesthesia in children and can cause poor oxygenation. Lung recruitment manoeuvre has been proposed as a strategy to counteract atelectasis. In this feasibility study, we evaluated whether a recruitment manoeuvre in children with a supraglottic airway restores end-expiratory lung volume (EELV) to baseline using electrical impedance tomography. After ethics committee approval (BASEC 2022-01833), we included children (ASA physical status 1-2, 10-20 kg) scheduled for anaesthesia with a supraglottic airway. We performed a recruitment manoeuvre by setting an anaesthesia machine to spontaneous breathing with a 3 L min^-1 fresh gas flow (fraction of inspired oxygen [Fio₂] 1.0) and the adjustable pressure-limiting (APL) valve set to 30 cmH₂O, until a pressure plateau was reached or a leak occurred. Data were collected at three time points: after induction of anaesthesia (baseline), after placement of a supraglottic airway, and after recruitment manoeuvre. The primary endpoint was the normalised change in end-expiratory lung impedance after the recruitment manoeuvre. The global inhomogeneity index was a secondary outcome. Equivalence was assumed if the 95% confidence interval for estimated ΔEELV remained within ±35% (±2 ml kg^-1). Of the 95 eligible children, we analysed 74 datasets. The median (95% confidence interval) estimated difference in EELV after recruitment manoeuvre vs baseline was -0.9 ml kg^-1 (-1.6 to -0.1), within the equivalence margin. No significant changes in global inhomogeneity index (0.0 [0.03-0.04]) were observed. In children undergoing general anaesthesia with the use of a supraglottic airway, a recruitment manoeuvre effectively restores EELV to baseline. NCT05672329.