The optimal warming strategy to reduce low body temperature during surgery
| ISRCTN | ISRCTN23065394 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN23065394 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | Nil known |
| Sponsor | Cooper University HealthCare, Department of Anesthesiology |
| Funder | Augustine Medical Inc., Eden Prairie, MN, USA |
- Submission date
- 08/03/2024
- Registration date
- 11/03/2024
- Last edited
- 16/06/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Surgery
Plain English summary of protocol
Background and study aims
Patients having surgery with anesthesia often lose body heat and become cold during the surgery. This can be associated with discomfort and, if significant, with medical side effects such as abnormal heart rhythm. A variety of methods and devices exist to warm patients up and/or prevent loss of body heat. While these are used routinely and are approved by regulatory agencies around the world, and are safe and (mostly) external to the body, the optimal combination and timing of their use is not entirely clear. The purpose of this study is to find out which of four combinations of warming strategies is optimal for these patients.
Who can participate?
Men and women at least 18 years of age, who are having elective abdominal, gynecologic, breast surgery, plastic/reconstructive or urological surgery under general anesthesia, where the operation is projected to last longer than 1.5 hours but less than 4 hours.
What does the study involve?
The patients will be randomly assigned to four groups that represent combinations of warming strategies. Group 1 will have an electrical warming blanket (conductive warming, or CW) used before their surgery and during their surgery. Group 2 will have a forced air blanket (FAW) used before and during their surgery. Group 3 will have no active warming before surgery and CW during surgery, but warm cotton blankets before the surgery will be allowed if patient wants to use them. And 4) will have no active warming before surgery and FAW during the surgery. Again in group 4 warm cotton blankets before the surgery will be allowed. All of these warming methods (CW and FAW) are well-established in practice and are achieved with common equipment. No method in and of itself is novel or lacking regulatory approval. All these methods are non-invasive.
What are the possible benefits and risks of participating?
The possible benefits are that if one of these groups turns out to be a superior strategy for keeping the patients warm, then those who have been assigned to that group will be more comfortable and/or will lose less body heat during their surgery. The risks are that the patient may have been assigned in a group where they will lose more body heat during the surgery.
Where is the study run from?
Cooper University HealthCare, New Jersey, USA.
When is the study starting and how long is it expected to run for?
February 2018 to August 2022
Who is funding the study?
Augustine Medical Inc., Eden Prairie, MN, USA
Who is the main contact?
Dr. Ronak Desai, D.O., Desai-ronak@cooperhealth.edu
Contact information
Public, Scientific, Principal investigator
One Cooper Plaza, Department of Anesthesiology
Camden
08103
United States of America
 ORCID ID |
0000-0001-7831-6492 |
|---|---|
| Phone | +1 856-342-2425 |
| Desai-ronak@cooperhealth.edu |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Prospective randomized non-blinded investigator-initiated clinical trial |
| Secondary study design | Randomised controlled trial |
| Participant information sheet | 45155 PIS 18-148 ICF.pdf |
| Scientific title | The optimal warming strategy to reduce perioperative hypothermia: a prospective randomized non-blinded clinical trial |
| Study objectives | 1. Active warming with a conductive warming system (CW) will be non-inferior in preventing hypothermia when compared to active warming with a forced air warming system (FAW). 2. Active preoperative warming with CW or FAW will lead to a reduction in intraoperative hypothermia when compared with only intraoperative warming with CW or FAW. 3. Active preoperative warming combined with intraoperative warming using CW is a superior strategy compared to only intra-operative warming with the CW, intraoperative warming with FAW only, or pre-operative and intra-operative warming with FAW. |
| Ethics approval(s) |
Approved 30/09/2019, Cooper University HealthCare IRB (One Cooper Plaza, Camden, NJ, 08103, United States of America; +1 (856) 757-7832; IRBOnlineHelp@cooperhealth.edu), ref: 18-148 |
| Health condition(s) or problem(s) studied | Patients having surgery with general anesthesia |
| Intervention | Participants are randomized to four groups, each representing a different preoperative warming approach: 1. Conductive prewarming (CW) and conductive intraoperative warming i.e. CW+CW; 2. Forced air (FAW) prewarming with forced air intraoperative warming i.e. FAW+FAW; 3. No active prewarming (NAPW) with conductive intraoperative warming i.e. NAPW+CW; and 4. No active prewarming (NAPW) with forced air intraoperative warming i.e. NAPW+FAW. Of note, all of these warming methods are well-established in practice and are achieved with commonly available methods/equipment. No method in and of itself is novel or lacking regulatory approval. All these methods are non-invasive. Duration of intervention: from signing of informed consent form and/or arrival to pre-operative surgical area (if form was signed ahead of time), to end of surgery. Duration of follow-up: 30 days post-surgery. Randomisation: we used a computer generated randomization list (Excel) to allocate subjects to one of four warming strategies in a 1:1:1:1 ratio. We used block randomization for scheduled surgical strata (1.5 h – 2.5 h and 2.5 – 4 h) and type of surgery (abdominal, gynecologic, breast surgery, plastic/reconstructive, urologic surgery) to ensure equal distribution of likely confounding variables. |
| Intervention type | Procedure/Surgery |
| Primary outcome measure(s) |
Intraoperative hypothermia magnitude will be the primary outcome. Hypothermia will be defined as a core temperature <36 °C and quantified as the intraoperative area under the curve (AUC) < 36 °C (units °C*hr) detected with an esophageal temperature probe. |
| Key secondary outcome measure(s) |
1. Lowest temperature measured intraoperatively: degrees C, measured via esophageal temperature probe. Recorded in the electronic anesthesia record. |
| Completion date | 08/08/2022 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 100 Years |
| Sex | All |
| Target sample size at registration | 184 |
| Total final enrolment | 184 |
| Key inclusion criteria | 1. Subjects undergoing elective abdominal, gynecologic, breast surgery, plastic/reconstructive or urological surgery under general anesthesia 2. Surgery projected to last longer than 1.5 hours, but no longer than 4 hours |
| Key exclusion criteria | 1. Cardiac surgery 2. Vascular surgery 3. Pregnancy 4. Age < 18 years 5. Imprisonment 6. Inability to provide written informed consent 7. Inability to speak and/or read English |
| Date of first enrolment | 04/12/2019 |
| Date of final enrolment | 08/08/2022 |
Locations
Countries of recruitment
- United States of America
Study participating centre
Camden, NJ
08103
United States of America
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Stored in publicly available repository |
| IPD sharing plan | The full dataset will be uploaded into https://datadryad.org/stash before submission to a journal for peer review. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | 12/06/2025 | 16/06/2025 | Yes | No | |
| Participant information sheet | 11/03/2024 | No | Yes | ||
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
| Protocol file | 22/05/2019 | 11/03/2024 | No | No |
Additional files
- 45155 18-148 PROTOCOL_22May2019.pdf
- Protocol file
- 45155 PIS 18-148 ICF.pdf
- Participant information sheet
Editorial Notes
16/06/2025: Publication reference added.
12/08/2024: The intention to publish date was changed from 31/08/2024 to 31/12/2024.
04/04/2024: The intention to publish date was changed from 01/04/2024 to 31/08/2024.
11/03/2024: Trial's existence confirmed by Cooper University Hospital.
