The Influence of Total Fat Mass and Skeletal Muscle Mass Index on the Occurrence of Perioperative Hypothermia in Patients Undergoing Open Gastrectomy.

Abstract

Background: Perioperative hypothermia, a common occurrence in patients undergoing general anesthesia, is defined as a core body temperature below 36°C. The relationship between patient body composition and the incidence of hypothermia remains underreported. This study aims to elucidate the association between body composition and perioperative hypothermia in patients undergoing open gastrectomy.

Methods: Patients undergoing open gastrectomy were enrolled in the study. Patients whose bladder temperature was lower than 36°C were allocated to the hypothermia group, and the other patients were allocated to the control group. The patient's body composition was evaluated by bioelectrical impedance analysis.

Results: A total of sixty-eight patients participated in this study. Among them, 34 experienced perioperative hypothermia (bladder temperature below 36°C) and were classified into the hypothermia group, while the remaining 34 were placed in the control group. The hypothermia group had a significantly higher body surface area per body weight. Additionally, the hypothermia group exhibited significantly lower total fat mass, skeletal muscle mass index, and basal metabolic rate (P < 0.05). However, body fat percentage and visceral fat mass did not differ significantly between the groups. Multivariate analysis identified total fat mass below 11.2 kg (HR 4.51, 95% CI: 1.35-15.03, P = 0.014) and skeletal muscle mass index below 10.06 kg/m² (HR 5.61, 95% CI: 1.86-16.93, P = 0.002) as independent risk factors for perioperative hypothermia.

Conclusions: Low total fat mass and a low skeletal muscle mass index are significant risk factors for perioperative hypothermia in patients undergoing open gastrectomy. These risk factors could improve the accuracy of identifying high-risk patients for perioperative hypothermia.