Perioperative Risk Factors for Intraoperative Hypothermia in Adult Patients Undergoing Elective Surgery at a National Referral Hospital in Bhutan: A Prospective Observational Study

Abstract

Objective: Intraoperative hypothermia is commonly encountered in anesthetic practice. It is related to several risk factors and can lead to various adverse events. It is important to detect it early and prevent the complications related to it. This study was done to identify incidence and perioperative risk factors of intraoperative hypothermia at a national referral hospital in Bhutan.Material and Methods: A prospective observational study was conducted in adult patients who underwent elective surgery lasting more than 30 minutes. Patient characteristics, incidence of hypothermia, and any interventions for treatment of hypothermia during the operation were recorded. Intraoperative hypothermia was defined as a core body temperature less than 36 °C measured with an esophageal probe.Results: Data were obtained from 91 patients with a mean (±standard deviation; S.D.) age of 42.3 (17.2) and American Society of Anesthesiologists (ASA) scores of 1 and 2 in 62.6% and 37.4% of the patients, respectively The patients underwent elective surgery with a mean (S.D.) duration of 73.24 (48.1) minutes and a mean (S.D.) duration of anaesthesia of 80.9 (49.2) minutes. The incidence of intraoperative hypothermia was 61.5% (56/91). Preoperative heart rate more than 80 beats per minute [hazard ratio (HR) 0.45, 95% confidence interval (CI), 0.26-0.77] was a protective factor and duration of anesthesia more than 60 minutes (HR 1.82, 95% CI, 0.98–3.38) was a risk factor for intraoperative hypothermia.Conclusion: Patients with a preoperative heart rate less than 80 beats per minute and undergoing duration of anesthesia more than 60 minutes should be assessed from the preoperative period and continuously monitored throughout the intraoperative period.