The effect of multimodal temperature management on the incidence of perioperative hypothermia in patients undergoing general anesthesia: a randomized controlled trial

Inadvertent Perioperative Hypothermia (IPH) remains a common clinical problem. This study aimed to evaluate the efficacy of a multimodal temperature management strategy versus passive insulation in reducing the incidence of IPH among patients undergoing general anesthesia. This was a single-center, randomized, assessor-blinded randomized trial conducted at our hospital from November to December 2025. This study enrolled 206 patients scheduled for 4–8 h surgeries. They were randomly assigned to either a multimodal group (preoperative warming, forced-air warming blanket, fluid warming, increased ambient temperature, pharmacological intervention) or a control group (passive insulation with cotton quilts). Core body temperature was monitored at multiple perioperative time points. The primary outcome was the incidence of intraoperative hypothermia (core temperature < 36 °C). Secondary outcomes included inflammatory markers, blood gas parameters, fluid balance, pain scores, postoperative complications, and hospital length of stay. Compared with the control group, the multimodal group had a significantly lower incidence of intraoperative hypothermia starting at 90 min after surgery initiation (T5: control 60.6% vs. multimodal 48.0%; adjusted OR 0.37, 95% CI 0.15–0.93) and continuing to the end of surgery (T11: control 69.2% vs. multimodal 27.5%; adjusted OR 0.08, 95% CI 0.03–0.23). The multimodal intervention also reduced the incidence of hypothermia at operating room discharge (28% vs. 72%; adjusted OR 0.12, 95% CI 0.06–0.24) and suggest a potential reduction in the risk of postoperative cardiac adverse events (0% vs. 3.85%; P = 0.045). The multimodal group showed a greater increase in inflammatory markers (TNF-α, NLR, PLR), less pain at 48 h postoperatively, and a smaller reduction in pH. This multimodal temperature management bundle significantly lowers the incidence of perioperative hypothermia in patients undergoing prolonged surgery under general anesthesia, with benefits starting at 90 min and strengthening over time. It stabilizes metabolic parameters and may reduce cardiac complications and pain at 48 h postoperatively. https://www.chictr.org.cnChiCTR2500112554.Registered17/11/2025, first recruitment 20/11/2025.