The effect of aggressive management of intraoperative body temperature on postoperative APACHE II score and prognosis in high-risk patients undergoing thoracoscopic surgery

Abstract

Background: Intraoperative hypothermia is related with postoperative complication, longer length of stay (LoS) and mortality. Acute Physiology and Chronic Health Evaluation II (APACHE II) it the most commonly used evaluation system for assessing the severity and clinical prognosis of patients. This study sought to examine the effect of intraoperative body temperature on postoperative APACHE II scores and the prognosis of high-risk patients undergoing thoracoscopic surgery.

Methods: This study used the clinical data of patients from a multicenter randomized controlled trial who had undergone thoracoscopic surgery at our center (NCT03111875). In our center were randomly assigned (1:1) to receive either aggressive warming to a target core temperature of 37 ℃ or routine thermal management to a target of 35.5 ℃ during non-cardiac surgery. Randomisation was computer-generated. Eligible patients (aged ≥45 years) had at least one cardiovascular risk factor, were scheduled for inpatient noncardiac surgery expected to last 2-6 h with general anaesthesia. We retrieved medical information through the electronic medical record system. The primary outcome was the postoperative APACHE II scores, APACHE II score variation. The secondary outcome was Quality of Recovery-15 (QoR-15) scores, LoS in hospital, postoperative complications, infections, and deaths of the patients were recorded, and a logistic regression analysis was conducted to stratify the risk factors for the APACHE II score.

Results: Group R comprised 121 patients and Group A comprised 84 patients. Group A had lower postoperative APACHE II scores (P=0.046) and a lower probability of a grade increase than Group R (P=0.005). However, no significant differences were found in terms of the QoR-15 scores, LoS, postoperative complications, infections, and deaths between the 2 groups. The logistic regression showed that aggressive warming, age, and the American Society of Anesthesiologists (ASA) grade were risk factors for the deterioration of postoperative APACHE II scores.

Conclusions: The active adoption of various passive and aggressive warming strategies to keep the core body temperature ≥37 ℃ during thoracoscopic surgery significantly reduced increases in APACHE II scores, which is different from age and ASA grade, and was the only intervention factor.

Keywords: APACHE II; Body temperature; core body temperature; prognosis; thoracoscopy.