Multi-center Validation of a Hypothermia Prediction Mobile Application (APP)

A Clinical Multicenter, Prospective, Observational Cohort Study to Validate a Prediction Mobile APP for Perioperative Hypothermia

There have been no fully validated tools for rapid screen of surgical patients at risk of intraoperative hypothermia. The aim of this study is to validate the performance of a previously established prediction model in estimating risk of intraoperative hypothermia using a prospective cohort before further implementation of the model. We hypothesize that the prediction model has helpful discrimination and adequate calibration [1] for clinical use.

This is a multicenter, prospective, observational cohort study to validate the property of a previously established mobile application (APP) [2] for estimating risk of intraoperative hypothermia. Patients scheduled for elective surgery under general anesthesia will be enrolled consecutively at 30 hospitals, which are randomly selected across China, between June, 2021 and December 2022. The total planned sample size is 3000 cases. Eligible participants will be identified, informed to sign the consent, and flagged at preoperative interview the day prior to the operation. Anesthetics and perioperative temperature management will be chosen at the discretion of the anesthesiologists without intervention. Intraoperative hypothermia risk score of each participant will be calculated by a mobile application of the predictor model [2] before surgery. A wireless axillary thermometer [3] will be used to continuously measure and record perioperative core temperature as the reference standard. All participants will be followed up until 30 days after the operation.

Inclusion Criteria:

• aged 18 years or older
• undergoing elective operation with general anesthesia or combined with other anesthesia
• operation is expected to last more than 40 minutes

Exclusion Criteria:

• central hyperthermia (e.g., cerebrovascular disease, traumatic brain injury, cerebral operation, epilepsy or acute hydrocephalus)
• impaired thermoregulation (e.g., neuroleptic malignant syndrome, malignant hyperthermia, or known hyperthyroidism/hypothyroidism with current thyroid dysfunction
• infectious fever
• core temperature ≥38.5 ℃ attributable to other causes within 3 days before surgery
• operation with induced hypothermia (e.g. cardiopulmonary bypass)
• unsuited for infrared tympanic thermometry or axillary temperature monitoring
• unwilling to give signed consent