Effect of Thermal Softening of Endotracheal Tubes on Perioperative Respiratory Adverse Events in Children Undergoing Adenotonsillectomy: A Randomized Controlled Trial

BACKGROUND: Perioperative respiratory adverse events (PRAEs) are a major source of morbidity in children undergoing adenotonsillectomy (AT). Thermal softening of polyvinyl chloride endotracheal tubes (ETTs) has been proposed to reduce airway irritation, yet its effect on PRAE incidence in the pediatric setting remains unclear. We sought to determine whether the use of thermally softened ETTs reduces PRAE incidence in children undergoing elective AT. METHODS: This prospective, randomized controlled trial enrolled 254 children aged 3-9 years scheduled for elective AT. Participants were randomly assigned to intubation with either a room-temperature ETT (Group T1) or a thermally softened ETT pre-warmed to 37°C (Group T2). The primary outcome was the occurrence of any PRAE-including coughing, oxygen desaturation, laryngospasm, or bronchospasm-from extubation through the second postoperative hour. Secondary outcomes included the incidence of individual PRAE components and perioperative hemodynamic and ventilatory parameters. Independent predictors of PRAEs were evaluated using multivariable logistic regression. RESULTS: Baseline characteristics were comparable between groups. The overall PRAE incidence was significantly lower in Group T2 than in Group T1 (14.1% vs. 24.6%; p = 0.039). Both laryngospasm (2.3% vs. 8.7%; p = 0.029) and postoperative coughing (11.7% vs. 21.4%; p = 0.043) occurred significantly less often in Group T2. No significant differences were detected in oxygen desaturation, bronchospasm, intraoperative hemodynamic parameters, or ventilatory variables. Multivariable analysis identified room-temperature ETT use (adjusted OR: 2.29; 95% CI: 1.16-4.54) and higher Obstructive Sleep Apnea-18 score (adjusted OR: 1.04; 95% CI: 1.01-1.07) as independent PRAE predictors. CONCLUSIONS: Warming ETTs to body temperature before intubation was associated with a meaningful reduction in PRAEs-particularly laryngospasm and postoperative coughing-in children undergoing AT. This straightforward, low-cost approach that requires no additional equipment or pharmacological agents may serve as a practical strategy to improve pediatric airway safety. Multicenter studies are needed to confirm these findings and clarify the underlying mechanisms. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06838260.