The Prevalence and Effect of Prewarming on Unintentional Perioperative Hypothermia in Patients Undergoing Major Abdominal Surgery Walking to the Operating Room: A Non-randomized Prospective Intervention Study.

Purpose: The purpose of the study was to determine the prevalence of unintentional perioperative hypothermia with and without preoperative warming and evaluate the effect of prewarming on core temperature in patients undergoing major abdominal surgery walking to the operating room (OR).

Design: A non-randomized prospective intervention study.

Methods: Participants were patients scheduled for major abdominal surgery and walking to the OR. The control group received a forced-air warming system during the surgery, whereas the intervention group received a forced-air warming system throughout the perioperative period. Core temperature was assessed on arrival to the OR and in 30-minute intervals after induction of anesthesia and during surgery and on arrival at the postanesthesia care unit (PACU).

Findings: Overall, 30 patients were included in the control group and 30 patients in the intervention group. Five patients (16.7%) in the intervention group and 19 patients (63.6%) in the control group were hypothermic at a given time in the perioperative period. The prevalence of hypothermia was significantly lower in the intervention group from 30 minutes after induction of anesthesia until arrival in the postanesthesia care unit. Prewarming reduced the drop in core temperature.

Conclusions: The prewarming method combined with peroperative active warming with forced-air warming in patients walking to the OR reduces the drop in core temperature and the prevalence of unintentional perioperative hypothermia throughout the perioperative period.