Research on Intraoperative Hypothermia Risk Prediction Model and Temperature Management Strategy for Elderly Patients During Surgery Based on Dynamic Incremental Training

NCT ID: NCT06676735

Last Updated: 2026-01-16

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 1323 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-03-11
• Study Completion Date: 2026-01-14

Brief Summary

With the support of partial dual temperature monitoring (comparing the specific difference between standardized axillary temperature monitoring and esophageal temperature), this trial is divided into the following three parts:

1. Multi center observational study: Establish and validate a dynamic incremental training intraoperative hypothermia prediction model - Intelligent Care for the Elderly (ICE) - Intraoperative hypothermia warning system, and provide ICE Offline for use by healthcare professionals and ICE Online for further model updates when needed for clinical or research purposes.

2. Multi center non randomized controlled clinical trial: Conduct a multi center stratified temperature management clinical trial based on ICE Offline after dynamic incremental training to verify the clinical and economic benefits of the model and active warming.

3. Pre and post comparative study: Collect data before ICE application and compare it with data after ICE promotion.

Conditions

Intraoperative Hypothermia

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: DOUBLE

Study Groups

Intraoperative hypothermia low risk group

Patients included this group are determined by prediction model. Operating room environment temperature was set at not less than 21°C, with a relative humidity of 50% to 60%. Patients are covered from neck to feet with a cotton blanket and the area to be disinfected and operated on is uncovered after induction of anesthesia. All patients will be administered intravenous fluid warmers and irrigation fluid prewarming (37℃\~43℃).

Group Type: EXPERIMENTAL

Prediction of intraoperative hypothermia risk

Intervention Type: DIAGNOSTIC_TEST

According to the Intelligent Care For The Elderly (ICE, an optimized model based on the existing prediction model of our research group after dynamic incremental training), patients are divided into intraoperative hypothermia lowrisk group and intraoperative hypothermia high risk group.

Measurement of tympanic membrane temperature

Intervention Type: OTHER

As a intraoperative core temperature reference (measure every 15 minutes) for patients without esophageal temperature or nasopharyngeal temperature monitoring.

Intraoperative hypothermia high risk group

Patients included this group are determined by prediction model. In addition to the measures taken in intraoperative hypothermia low risk group, an inflatable warming system, including a forced air warming system and forced air warming blanket, is employed for prewarming before anesthesia initiation and for maintaining body temperature throughout the operation. During the surgery, the insulation blanket will be applied to non surgical areas, and the host temperature will be adjusted to 38 ℃ for warming. If the temperature of the patient is lower than 36 ℃, the temperature of the system can be adjusted to 43 ℃; if the temperature of the patient is higher than 37 ℃, the temperature of the system can be adjusted to 32 ℃. After the patient's temperature is normal, it can be adjusted back to 38 ℃.

Group Type: EXPERIMENTAL

Inflatable warming system

Intervention Type: DEVICE

Inflatable warming system, including a forced air warming system (IOB, WU505) and forced air warming blanket (IOB-001, IOB-006, IOB-011), is employed for prewarming before anesthesia initiation and for maintaining body temperature throughout the operation. During the surgery, the insulation blanket will be applied to non surgical areas, and the host temperature will be adjusted to 38 ℃ for warming. If the temperature of the patient is lower than 36 ℃, the temperature of the system can be adjusted to 43 ℃; if the temperature of the patient is higher than 37 ℃, the temperature of the system can be adjusted to 32 ℃. After the patient\'s temperature is normal, it can be adjusted back to 38 ℃.

Prediction of intraoperative hypothermia risk

Intervention Type: DIAGNOSTIC_TEST

According to the Intelligent Care For The Elderly (ICE, an optimized model based on the existing prediction model of our research group after dynamic incremental training), patients are divided into intraoperative hypothermia lowrisk group and intraoperative hypothermia high risk group.

Measurement of tympanic membrane temperature

Intervention Type: OTHER

As a intraoperative core temperature reference (measure every 15 minutes) for patients without esophageal temperature or nasopharyngeal temperature monitoring.

Model optimization group

Only observe the patient's baseline, intraoperative hypothermia, postoperative complications, and other indicators, and collect data through the electronic Data Capture System to optimize existing intraoperative hypothermia prediction model. The estimated sample size is 600 cases by the incremental learning curve calculating.

Group Type: OTHER

The difference between axillary temperatature and core temperature in elderly patients

Intervention Type: OTHER

Previous studies have shown that the difference and standard deviation between esophageal temperature and axillary temperature are core 0.05 ℃ and 0.26 ℃, respectively. In light of 10% dropout rate, a integer sample size of 400 achieves 95% power to detect a mean of paired differences of 0.05 with an estimated standard deviation of paired differences of 0.26 and with a significance level (alpha) of 0.05 using a two-sided paired t-test. So 400 patients in the Model optimization group need to undergo core temperature (esophageal temperature or nasopharyngeal temperature).

Measurement of tympanic membrane temperature

Intervention Type: OTHER

As a intraoperative core temperature reference (measure every 15 minutes) for patients without esophageal temperature or nasopharyngeal temperature monitoring.

Group of model benefit evaluation

Data of this group is medical records before the application of the intraoperative hypothermia prediction model, which will be collected from the electronic medical record system.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Inflatable warming system

Inflatable warming system, including a forced air warming system (IOB, WU505) and forced air warming blanket (IOB-001, IOB-006, IOB-011), is employed for prewarming before anesthesia initiation and for maintaining body temperature throughout the operation. During the surgery, the insulation blanket will be applied to non surgical areas, and the host temperature will be adjusted to 38 ℃ for warming. If the temperature of the patient is lower than 36 ℃, the temperature of the system can be adjusted to 43 ℃; if the temperature of the patient is higher than 37 ℃, the temperature of the system can be adjusted to 32 ℃. After the patient\'s temperature is normal, it can be adjusted back to 38 ℃.

Intervention Type: DEVICE

Prediction of intraoperative hypothermia risk

According to the Intelligent Care For The Elderly (ICE, an optimized model based on the existing prediction model of our research group after dynamic incremental training), patients are divided into intraoperative hypothermia lowrisk group and intraoperative hypothermia high risk group.

Intervention Type: DIAGNOSTIC_TEST

The difference between axillary temperatature and core temperature in elderly patients

Previous studies have shown that the difference and standard deviation between esophageal temperature and axillary temperature are core 0.05 ℃ and 0.26 ℃, respectively. In light of 10% dropout rate, a integer sample size of 400 achieves 95% power to detect a mean of paired differences of 0.05 with an estimated standard deviation of paired differences of 0.26 and with a significance level (alpha) of 0.05 using a two-sided paired t-test. So 400 patients in the Model optimization group need to undergo core temperature (esophageal temperature or nasopharyngeal temperature).

Intervention Type: OTHER

Measurement of tympanic membrane temperature

As a intraoperative core temperature reference (measure every 15 minutes) for patients without esophageal temperature or nasopharyngeal temperature monitoring.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Elderly patients (aged 60 and above) undergoing non cardiac elective surgery under general anesthesia;
• 30 minutes ≤ Estimated surgical duration ≤ 240 minutes ;
• Normal preoperative bleeding and clotting time
• American society of Aneshesiologists physical status classification system:Ⅰ～Ⅳ

Exclusion Criteria

• Mental illness
• Cirrhosis
• Existence or potential central hyperthermia
• Metabolic thermoregulatory abnormalities
• History of malignant hyperthermia or family history
• Extensive skin burns or injuries
• Seriously infect
• Long term use of nonsteroidal anti-inflammatory drugs
• Expected difficult airway
• Researchers believe that individuals who are not suitable to participate in clinical trial
• Refusal to sign informed consent form
• Withdraw informed consent form
• Severe bleeding or shock during perioperative period.

• Minimum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

First Affiliated Hospital of Chongqing Medical University

OTHER

Sponsor Role: lead

Responsible Party

Min Su

Director

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

First Affiliated Hospital of Chongqing Medical University

Chongqing, Chongqing Municipality, China

Countries

China

Other Identifiers

ZZ2024-173-01

Identifier Type: -

Identifier Source: org_study_id