Background: Intraoperative hypothermia is common during spine surgery despite routine warming measures. Because conventional temperature outcomes do not fully reflect cumulative thermal stress, we aimed to quantify the real-world burden of intraoperative hypothermia using burden-based metrics. Materials and Methods: This retrospective observational study included adult patients who underwent spine surgery in a single operating unit between June and December 2023. Patients without a warming device, those managed with more than one warming device, and those with incomplete temperature data were excluded from this study. Perioperative warming was initiated on arrival in the operating room and maintained intraoperatively using a single active warming device. The primary outcome was hypothermic burden, assessed by the proportion of intraoperative time spent below 36.0°C and the area under the temperature threshold (AUTT). Hypothermia incidence and other temperature-related variables were also described. Results: Of 158 screened patients, 128 were included in the final analysis. Median anesthesia duration was 220 (160–275) min. Despite routine perioperative warming, patients experienced a substantial burden of intraoperative hypothermia: the median proportion of intraoperative time spent below 36.0°C was 77.8 (55.8–88.3)%, corresponding to 139 (95.3–200) min, and the median AUTT was 57.4 (14.3–123)°C min. The median lowest intraoperative temperature was 35.3 (35.1–35.7)°C, and 91.4% of patients experienced at least one intraoperative temperature below 36.0°C. Conclusion: Routine warming initiated on operating room arrival did not adequately prevent substantial intraoperative hypothermic burden during spine surgery. More proactive perioperative thermal management may be required.
Kwon et al. (Sat,) studied this question.