An interventional study of Bair Hugger™ Temperature Management Unit Model 750 and 3M™ Bair Paws™ Flex Gown in Temperature Change, Body, sponsored by University of Missouri-Columbia. Terminated at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2023-10-02.
Sponsored by University of Missouri-Columbia · Not applicable, Interventional, and Treatment
This prospective randomized clinical trial will assess the effect of pre-operative convective warming on intra-operative thermoregulation in patients undergoing gastrointestinal or genitourinary surgical procedures with the Tiger anesthesia perioperative protocol.
By the year 2030 the geriatric presence in the United States, defined as any adult >65 years of age, is estimated to reach around 20% of the entire population. Thus, understanding medical concepts as they relate to the elderly is becoming increasingly important. One such concept is that of hypothermia - a core body temperature \< 36°C - for which age >65 has been found to be an independent risk factor. This complication is especially prevalent intra-operatively due to use of general anesthetics, cool ambient operating room (OR) temperatures, and impaired thermal regulation in the elderly.
The human body employs numerous mechanisms to maintain thermal homeostasis including: behavioral means of thermoregulation, sweating, pre-capillary vasodilation, non-shivering and shivering means of heat production, and arteriovenous shunt vasoconstriction. The first, and arguably most important, regulatory response to occur is that of vasoconstriction, which normally results in redistribution of blood from the relatively cool periphery to the warmer core compartment in order to confine metabolic heat to the central tissues. Patients undergoing general anesthesia experience reduced vasoconstriction due to decreased cold response thresholds while patients undergoing epidural anesthesia experience sympathetic blocks resulting in blunted vasoconstrictive responses. All patients experience the afore mentioned side effects of anesthetics, however it has been proven that the elderly are more susceptible to hypothermia due to lower vasoconstriction thresholds - determined by a temperature gradient of 4°C between the periphery and core.
First explored by Kurz et al. in 1993, it was found that use of nitrous oxide and isoflurane anesthesia lead to an approximately 1.2°C lower vasoconstriction threshold of 33.9±0.6 in the elderly versus 35.1±0.3 in the young (p \< .01). This subject was again looked at in a 1997 study wherein the vasoconstriction threshold during nitrous oxide and sevoflurane was observed to be decreased by approximately 0.8°C in the elderly at 35.0±0.8 versus 35.8±0.3 in the young (p \< .01). This is relevant because intraoperative hypothermia has long been known to lead to adverse outcomes such as increased incidence of myocardial ischemia, arrhythmias, coagulopathic states, and wound infections. In a 2014 retrospective cohort study by Billeter et al. patient's experiencing core temperatures \<35°C had a four times increase in mortality with complication rates increasing two fold and incidence of stroke increasing six fold. To counter this thermoregulatory failure in patients, numerous methods of warming have been practiced over time to augment the normal body response.
One method used to decrease intraoperative hypothermia is warming patients before surgery via skin surface warmers. Numerous studies have found that even brief periods of pre-warming can improve intraoperative temperatures significantly for as long as 75-90 minutes after induction. In procedures lasting less than 90 minutes, Horn et al. found that as little as 10 minutes of pre-warming decreased incidence of intraoperative hypothermia from 69% to just 13% while Torossian et al. decreased the incidence from 60% to 38% in his study using a self-warming blanket for 30 minutes pre-operatively. Studies have also shown that longer pre-warming, of 45-60 minutes, can prevent hypothermia for up to 2 hours after induction.
While significant research has been performed on the effects of warming patients before they undergo surgical procedures, scant evidence demonstrates the effect of pre-warming in the elderly. In one article specifically looking at pre-warming in the elderly (mean age \~72-73) it was found that, after pre-warming for 20 minutes, there was no significant change in incidence of hypothermia but there was a significant difference in severity of hypothermia when it did occur. This study focused only on men undergoing transurethral resection of the prostate however, and suffers from lack of generalizability. With the proportion of the geriatric population continuing to expand, and the potential adverse effects resulting from their increased susceptibility to intraoperative hypothermia, it is of the utmost importance to look into methods to counter this dilemma and expand the database on the topic.
97 studies on the registry are indexed under Body Temperature Changes; 20 are open to participants now.
This study's enrollment of 10 is below the median of 40 across 68 interventional studies indexed under Body Temperature Changes.
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Of its 43 completed or terminated interventional studies of FDA-regulated products, 29 (67%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Undergo convective warming during the preoperative preparations, completed for a minimum of 60 minutes prior to entering the operating room
Device: Bair Hugger™ Temperature Management Unit Model 750 · Device: 3M™ Bair Paws™ Flex Gown
Undergo standard of care, which includes providing each patient with blankets and sheets, as well as more blankets on patient request.
Forced-air temperature management unit used for preoperative and intraoperative participant warming
Bair Paws™ patient warming gown used for preoperative and intraoperative participant warming
Core Body Temperature
Change in core temperature between induction of anesthesia and end of skin preparation
Time frame: Day 1
Skin Temperature
Change in skin temperature between arrival to the holding area and departure to the operating room, and arrival to the PACU
Time frame: Day 1
Intraoperative Temperatures
Core body temperature measured intraoperatively
Time frame: Day 1
Temperature Differences Between Different Age Groups
Differences in temperature changes between elderly (≥ 65 years) and younger patients (\< 65 years).
Time frame: Day 1
| Milestone | Convective Pre-warming | Standard of Care |
|---|---|---|
| Started | 6 | 4 |
| Completed | 6 | 4 |
| Not completed | 0 | 0 |
Change in core temperature between induction of anesthesia and end of skin preparation
| Degrees Celsius | Convective Pre-warming | Standard of Care |
|---|---|---|
| Core Body Temperature | -0.95 ± 0.69 | -0.53 ± 0.85 |
Change in skin temperature between arrival to the holding area and departure to the operating room, and arrival to the PACU
| Degrees Celsius | Convective Pre-warming | Standard of Care |
|---|---|---|
| Holding area to operating room departure | -0.03 ± 0.39 | 0.08 ± 0.42 |
| Holding area to arrival in PACU | -0.07 ± 0.67 | -0.48 ± 0.56 |
Core body temperature measured intraoperatively
| Degrees Celsius | Convective Pre-warming | Standard of Care |
|---|---|---|
| Intraoperative Temperatures | 36.0 ± 0.79 | 35.7 ± 0.17 |
Differences in temperature changes between elderly (≥ 65 years) and younger patients (\< 65 years).
| Degrees Celcius | Convective Pre-warming | Standard of Care |
|---|---|---|
| Temperature before prewarming - Patients <65 years of age | 36.5 ± 0.2 | — |
| Temperature before prewarming - Patients >65 years of age | 36.6 ± 0.6 | 36.5 ± 0.4 |
| Temperature after prewarming - Patients <65 years of age | 36.5 ± 0.3 | — |
| Temperature after prewarming - Patients >65 years of age | 36.4 ± 0.5 | — |
Collected over 1 Day. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Convective Pre-warming | 0/6 (0%) | 0/6 (0%) | 0/6 (0%) |
| Standard of Care | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| Age, Continuous(years) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| Mean | 59.8 ± 19 | 69.5 ± 2.4 | 63.7 ± 15.1 |
| Sex: Female, Male(Participants) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| Female | 1 | 0 | 1 |
| Male | 5 | 4 | 9 |
| Ethnicity (NIH/OMB)(Participants) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 |
| Not Hispanic or Latino | 6 | 4 | 10 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 6 | 4 | 10 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| United States | 6 | 4 | 10 |
| Body Mass Index (BMI)(kg/m^2) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| Mean | 30 ± 5.7 | 33.7 ± 12.1 | 30.9 ± 8.5 |
| American Society of Anesthesiologists (ASA) Physical Status Classification (PS Class)(Participants) | Convective Pre-warming | Standard of Care | Total |
|---|---|---|---|
| ASA PS Class 2 | 4 | 3 | 7 |
| ASA PS Class 3 | 2 | 1 | 3 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Oct 2017 to primary completion in Nov 2018, 12 months.
Results were first posted in Oct 2023, 4 years 10 months after primary completion.
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This study is terminated, as verified in Sep 2023. You cannot join it, but the record below documents what was studied.
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