Incidence and Risk Factors of Intraoperative Hypothermia in Adult Patients After Protocol Implementation

Incidence and Risk Factors of Intraoperative Hypothermia in Adult Patients at Siriraj Hospital: An Evaluation After Implementation Management Protocol

Inadvertent intraoperative hypothermia is one of the most common complications in patients undergoing anesthesia. This condition is strongly associated with several adverse clinical. At Siriraj Hospital, a previous study revealed a high incidence rate of 74.4%, with only 16.3% of patients receiving intraoperative temperature monitoring. In response to these findings, Siriraj Hospital implemented a perioperative temperature management guideline in July 2024. However, it remains to be evaluated whether the implementation of this protocol has led to a meaningful change in clinical practice. The primary concern is whether the adherence to temperature monitoring for surgeries exceeding one hour has improved from the historical rate of 16.3%, and subsequently, whether this has resulted in a decreased incidence of hypothermia.

Study Overview

• Status: Active, not recruiting
• Conditions: Hypothermia Following Anesthesia

Detailed Description

Inadvertent intraoperative hypothermia, defined as a core body temperature below 36 C, is one of the most common complications in patients undergoing anesthesia. This condition is strongly associated with several adverse clinical outcomes, including increased risk for surgical site infections, delayed wound healing, prolonged recovery and hospitalization, coagulopathy, and increased requirements for blood transfusion. Many risk factors are associated with inadvertent intraoperative hypothermia including: high ASA physical status, age >65-year, general anesthesia combined with neuraxial anesthesia, longer anesthesia duration, emergency major surgery, intraoperative blood loss and intravenous fluid volume received.

Despite the existence of international recommendations from organizations like the American Society of Anesthesiologists (ASA) and the National Institute for Health and Care Excellence (NICE)-which recommend interventions including active warming, using warm irrigation fluid, and continuous temperature monitoring to minimize the risk of intraoperative hypothermia, hypothermia remains prevalent in many settings. At Siriraj Hospital, a previous study revealed a high incidence rate of 74.4%, with only 16.3% of patients receiving intraoperative temperature monitoring. In response to these findings, Siriraj Hospital implemented a standardized perioperative temperature management guideline (protocol) in July 2024. This protocol recommends pre-warming and active warming strategies to mitigate extrinsic risk factors, such as low operating room temperatures and the administration of cold intravenous fluids.

However, it remains to be evaluated whether the implementation of this protocol has led to a meaningful change in clinical practice. The primary concern is whether the adherence to temperature monitoring for surgeries exceeding one hour has improved from the historical rate of 16.3%, and subsequently, whether this has resulted in a decreased incidence of hypothermia. Furthermore, intrinsic patient factors-such as age, Body Mass Index (BMI), and surgical complexity-continue to be potential variables that the protocol alone may not fully address.

To date, the real-world impact of this specific protocol on reducing hypothermia has not been formally evaluated. Therefore, this study is essential to evaluate the effectiveness of the Siriraj temperature management protocol. The findings will not only determine the current intraoperative monitoring rate and the incidence of hypothermia but also identify significant intrinsic risk factors that persist despite standardized care. This information will be vital for further quality improvement and ensuring patient safety in the perioperative setting at Siriraj Hospital.

• Study Type: Observational
• Enrollment (Actual): 361

Contacts and Locations

Study Locations

• Thailand
  • Bangkok
    • Bangkok, Bangkok, Thailand, 10700
      • Siriraj Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Adult patients undergoing non-cardiac surgery under anesthetic care at Siriraj Hospital, a tertiary's care hospital in Bangkok, Thailand.

Description

Inclusion Criteria:

• Adult patients undergoing non-cardiac surgery under anesthesia service Patients undergoing surgery after the implementation of the temperature management protocol (from July 2024 onwards)

Exclusion Criteria:

• Procedures performed under local anesthesia or monitored anesthetic care Anesthesia duration of less than 60 minutes

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of intraoperative hypothermia	Presence of hypothermia defined as core temperature less than 36 C	November to December 2025

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The proportion of patients who received intraoperative temperature monitoring	Percentage of patients receiving intraoperative temperature monitoring	November to December 2025
Time to onset hypothermia, duration of hypothermia, lowest temperature		November to December 2025
Incidence of postoperative hypothermia	Percentage of patients having core temperature less than 36 C at the arrival of the recovery unit	November to December 2025
Recovery time	Time from finished operation to patient transfer recorded in minutes	November to December 2025
Blood loss	Amount of blood loss recorded in mL	November to December 2025
Length of post-anesthesia care unit stay	The amount of time the patient spent in the recovery unit was recorded in minutes.	November to December 2025
Length of hospital stay	The total admission days recorded in days	November to December 2025
Blood transfusion	Amount of blood transfusion given intraoperatively in mL	November to December 2025

Collaborators and Investigators

• Sponsor: Siriraj Hospital

Study record dates

Study Major Dates

• Study Start (Actual): February 27, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: March 6, 2026
• First Submitted That Met QC Criteria: March 10, 2026
• First Posted (Actual): March 13, 2026

Study Record Updates

• Last Update Posted (Actual): March 13, 2026
• Last Update Submitted That Met QC Criteria: March 10, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Hypothermia; Intraoperative hypothermia
• Additional Relevant MeSH Terms: Body Temperature Changes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hypothermia
• Other Study ID Numbers: 053/2569(IRB2)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED