Head-up lateral positioning during emergence from anaesthesia after ambulatory adenotonsillectomy in children: protocol for a multicentre randomised controlled trial

Tonsillectomy and adenoidectomy are common paediatric surgeries, with > 50% of children experiencing postoperative respiratory adverse events (PRAEs). Existing mitigation strategies have limitations, and evidence on positional interventions (e.g. lateral/semi-reclined) specifically for paediatric tonsillectomy/adenoidectomy remains scarce. This study aims to evaluate the effect of head-up 30° lateral positioning during anaesthesia emergence on PRAEs. This is a multicentre, prospective, parallel-group, superiority randomised controlled trial conducted at four tertiary hospitals in China. A total of 350 children will be randomly allocated 1:1 to the head-up 30° lateral-position group or the supine flat-lying group using centre-stratified block randomisation. Because the allocated position is directly visible, PACU primary-outcome assessors will not be blinded; postoperative follow-up assessors and data analysts will remain blinded to treatment allocation. The primary outcome is the proportion of participants experiencing at least one postoperative respiratory adverse event (PRAE) from removal of the endotracheal tube until discharge from the PACU. Secondary outcomes include the frequency of PRAEs, emergency airway interventions, tracheal extubation time, PACU stay duration, length of hospital stay, and postoperative respiratory outcomes at 24 h and 7 days. This is the first prospective, multicentre, randomised controlled trial to evaluate the effect of head-up 30° lateral positioning during anaesthesia emergence on postoperative respiratory adverse events (PRAEs) in paediatric patients undergoing tonsillectomy and adenoidectomy. The findings from this study will contribute valuable information to the management of PRAEs in children, a common and significant complication after these surgeries. Clinicaltrials.gov NCT07108218. Registered on 31 July 2025. https://clinicaltrials.gov/ .