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Cooling Vest May Reduce Heat Stress During Surgery

Cooling Vest May Reduce Heat Stress, Improve Thermal Comfort, and Preserve Cognitive Performance of Surgeons While Performing Surgery

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04511208
Enrollment
30
Registered
2020-08-13
Start date
2020-08-25
Completion date
2022-02-25
Last updated
2022-07-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Body Temperature Changes

Brief summary

The investigators will propose a randomized cross-over trial using a uniform and strongly balanced 4-period design in which will include four operations for each surgeon. Surgeons will be randomized to 1 of 4 sequences: ABBA, BAAB, AABB or BBAA. The design is uniform in that each treatment appears the same number of times within each sequence (uniform within sequence) and if each treatment appears the same number of times within each period (uniform within each period). It is strongly balanced with respect to first-order carryover effects because each treatment precedes every other treatment, including itself, the same number of times

Detailed description

The subjects will be randomly assigned to use either the CoolSource™ cooling vest (worn between scrubs) and a conventional surgical gown for each of 4 surgeries. Sequence of treatments within the subjects will be randomized (ABBA, BAAB, AABB or BBAA), and determined using the PLAN procedure in SAS, such that each surgeon will wear vest and non-vest twice. The sequencing will not be shared with any study personnel. Allocation for each case will be concealed with a web-based system that will be accessed only shortly before surgery. The investigators will target an ambient temperature of 21°C ± 1°C, and try to maintain the same temperature of each of the four study cases for each surgeon. The CoolSource vest holds six reusable cooling packs located bilaterally on the shoulders, angled flank along the base of the rib cage, and along each side of the spine, mid-back. The vest will be donned over hospital-issued scrubs after all temperature sensing devices have been applied and before surgical hand scrubbing. The subjects will wear the vest throughout surgery, and for a few additional minutes while postoperative assessments are made (details below). The weight of the disposable cooling vest is 1 kg which is evenly distributed over both shoulders. The cooling packs have an insulated cover to reduce condensation or sweating while seated inside the vest pocket. The flexible frozen reusable cooling packs will be inserted into each of the six pockets and the vest belt will be tied to hold the cooling packs securely. The disposable cooling vests will be discarded after each case, and the cooling packs returned to a freezer.

Interventions

Evaluate that wearing a cooling vest during surgery reduces surgeons' mean-body temperature and preserves their cognitive performance.

DEVICEWithout cooling vest

Evaluate surgeons' mean-body temperature and cognitive performance without cooling vest.

Sponsors

The Cleveland Clinic
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
25 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* Surgeons who perform elective major orthopedic surgery such as total hip and knee arthroplasties scheduled for 90 to 150 minutes at the Cleveland Clinic Main Campus. * Orthopedic surgeons ages of 25-65 years old, as body temperatures may be lower and less stable in the elderly (Waalen & Buxbaum, 2011), who operate frequently enough to participate in four cross-over cases. * Surgical helmet system is consistently worn for each of the surgeon's four cases, if used in the first case.

Exclusion criteria

* Surgical cases that require surgeons to sit on stools during the procedure, which may impact temperature and energy expenditure. * \- Surgeons who report having a recent illness within 24 hours prior to the surgery, symptoms producing a febrile condition; * Surgeons who worked the previous evening. * Surgeons who wear lead X-ray gowns.

Design outcomes

Primary

MeasureTime frameDescription
Self-rated Thermal Comfort.Immediately after surgery, within 10 minutesImmediately after surgery, while still gowned, surgeons will rate their thermal comfort on a 0-10 Likert scale, with 0 representing extreme cold, 5 being thermal comfort, and 10 representing extreme heat. Two points on the 11-point Likert scale will be considered a clinically important difference.

Secondary

MeasureTime frameDescription
Mean Skin Temperaturethe sensor will be worn for a total of 90 minutesThe second secondary outcome will be the mean skin temperature for a case, calculated as the time-weighted average over the taken measurements. Mean skin temperature will be estimated from skin temperature from the back of the upper chest, deltoid arm, thigh, and calf using the formula \[MSTR = 0.3 chest + 0.3 arm + 0.2 thigh + 0.2 leg or 0.3(chest + arm) + 0.2(thigh + 0.2 leg)\] (Ramanathan, 1964). Skin temperature will be continuously measured using wireless patches, TempTraq, which meet professional accuracy standards for digital thermometers (ASTM E1112-00). The sensors will remain affixed with adhesive dressing on the surgeon's body surface throughout surgery and approximately 10 minutes required for post-operative testing.
Surgeons' Cognitive Performance, Measured With the C3B Battery.Immediately after surgery, within 10 minutesSurgeons' cognitive performance was assessed with the Cleveland Clinic Cognitive Battery (C3B, Cleveland, OH), a ten-minute-long self-administered computer tablet program that tests visual memory (episodic learning and delayed memory, range 0 - 70) and processing speed (information processing speed and incidental memory, range 40 - 120). Testing will take place right after surgery with surgeons still gowned. The surgeons will sit with the iPad touch screen placed on a desk in front of them for approximately 10 minutes to complete the cognitive test.
Mean Core Temperature.the sensor will be worn for a total of 90 minutesThe first secondary outcome will be the mean core temperature for a case, calculated as the time-weighted average over the taken measurements. The surgeon's core body temperature will be monitored by a validated wireless wearable iThermonitor WT701 biosensor which estimates core temperature within ±0.5⁰C (Pei et al., 2018). The sensor will be applied to the surgeon's right axilla 15-20 minutes prior to the surgical hand scrub performed at the start of surgery and secured with an adhesive cover. A small patch of axillary hair will be clipped or shaved as necessary.
Surgeon' Perceived Fatigue Measured as 0 Representing Not Fatigued at All, 5 Moderately Fatigued, and 10 Total Fatigue & ExhaustionImmediately after surgery, within 10 minutesPerceived fatigue will be rated on a 0-10 ROF scale, with 0 representing not fatigued at all, 5 moderately fatigued, and 10 total fatigue & exhaustion. Two points difference on either scale will be considered a clinically important difference.
Surgeons' Perception and Amount of Sweat-soaked Scrub Clothing.Immediately after surgery, within 10 minutesImmediately after surgery, while still gowned, surgeons' perception and amount of sweat-soaked scrub clothing will be rated using a Likert scale from 0 = not wet at all to 10 = fully drenched.
Surgeon' Perceived Ergonomic Workload Measured With the Borg Rating of Perceived Exertion (RPE) Scale.Immediately after surgery, within 10 minutesImmediately after surgery, while still gowned, surgeons will rate their perceived exertion on the Borg scale which ranges from 6 (no exertion) to 20 (maximal exertion).

Countries

United States

Participant flow

Participants by arm

ArmCount
All Study Participants
All participants were randomized to receive all interventions
30
Total30

Baseline characteristics

CharacteristicAll Study Participants
Age, Continuous36.5 years
STANDARD_DEVIATION 9
Body Mass Index (BMI)26 kg/m^2
Height181 cm
Race/Ethnicity, Customized
Asian
2 participants
Race/Ethnicity, Customized
Black/African American
1 participants
Race/Ethnicity, Customized
Hispanic/Latino
1 participants
Race/Ethnicity, Customized
White/Caucasian
26 participants
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
30 Participants
Weight85 kg

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 300 / 30
other
Total, other adverse events
0 / 300 / 30
serious
Total, serious adverse events
0 / 300 / 30

Outcome results

Primary

Self-rated Thermal Comfort.

Immediately after surgery, while still gowned, surgeons will rate their thermal comfort on a 0-10 Likert scale, with 0 representing extreme cold, 5 being thermal comfort, and 10 representing extreme heat. Two points on the 11-point Likert scale will be considered a clinically important difference.

Time frame: Immediately after surgery, within 10 minutes

ArmMeasureValue (MEAN)Dispersion
Cooling VestSelf-rated Thermal Comfort.4.4 score on a scaleStandard Error 0.19
Without Cooling VestSelf-rated Thermal Comfort.6.6 score on a scaleStandard Error 0.19
p-value: <0.00195% CI: [-2.7, -1.7]Repeated measures linear model
Secondary

Mean Core Temperature.

The first secondary outcome will be the mean core temperature for a case, calculated as the time-weighted average over the taken measurements. The surgeon's core body temperature will be monitored by a validated wireless wearable iThermonitor WT701 biosensor which estimates core temperature within ±0.5⁰C (Pei et al., 2018). The sensor will be applied to the surgeon's right axilla 15-20 minutes prior to the surgical hand scrub performed at the start of surgery and secured with an adhesive cover. A small patch of axillary hair will be clipped or shaved as necessary.

Time frame: the sensor will be worn for a total of 90 minutes

ArmMeasureValue (MEAN)Dispersion
Cooling VestMean Core Temperature.32.9Standard Error 0.09
Without Cooling VestMean Core Temperature.33.2Standard Error 0.09
p-value: 0.00695% CI: [-0.44, -0.08]Repeated measures linear model
Secondary

Mean Skin Temperature

The second secondary outcome will be the mean skin temperature for a case, calculated as the time-weighted average over the taken measurements. Mean skin temperature will be estimated from skin temperature from the back of the upper chest, deltoid arm, thigh, and calf using the formula \[MSTR = 0.3 chest + 0.3 arm + 0.2 thigh + 0.2 leg or 0.3(chest + arm) + 0.2(thigh + 0.2 leg)\] (Ramanathan, 1964). Skin temperature will be continuously measured using wireless patches, TempTraq, which meet professional accuracy standards for digital thermometers (ASTM E1112-00). The sensors will remain affixed with adhesive dressing on the surgeon's body surface throughout surgery and approximately 10 minutes required for post-operative testing.

Time frame: the sensor will be worn for a total of 90 minutes

ArmMeasureValue (MEAN)Dispersion
Cooling VestMean Skin Temperature36.1Standard Error 0.13
Without Cooling VestMean Skin Temperature36.3Standard Error 0.13
p-value: 0.04695% CI: [-0.45, -0.005]Repeated measures linear model
Secondary

Surgeon' Perceived Ergonomic Workload Measured With the Borg Rating of Perceived Exertion (RPE) Scale.

Immediately after surgery, while still gowned, surgeons will rate their perceived exertion on the Borg scale which ranges from 6 (no exertion) to 20 (maximal exertion).

Time frame: Immediately after surgery, within 10 minutes

ArmMeasureValue (MEDIAN)
Cooling VestSurgeon' Perceived Ergonomic Workload Measured With the Borg Rating of Perceived Exertion (RPE) Scale.13 score on a scale
Without Cooling VestSurgeon' Perceived Ergonomic Workload Measured With the Borg Rating of Perceived Exertion (RPE) Scale.13 score on a scale
p-value: 0.00795% CI: [1.28, 4.68]Generalized linear mixed effects model
Comparison: Sensitivity analysisp-value: 0.00995% CI: [-1.82, -0.28]Repeated measures linear model
Secondary

Surgeon' Perceived Fatigue Measured as 0 Representing Not Fatigued at All, 5 Moderately Fatigued, and 10 Total Fatigue & Exhaustion

Perceived fatigue will be rated on a 0-10 ROF scale, with 0 representing not fatigued at all, 5 moderately fatigued, and 10 total fatigue & exhaustion. Two points difference on either scale will be considered a clinically important difference.

Time frame: Immediately after surgery, within 10 minutes

ArmMeasureValue (MEAN)Dispersion
Cooling VestSurgeon' Perceived Fatigue Measured as 0 Representing Not Fatigued at All, 5 Moderately Fatigued, and 10 Total Fatigue & Exhaustion2.3 score on a scaleStandard Error 0.26
Without Cooling VestSurgeon' Perceived Fatigue Measured as 0 Representing Not Fatigued at All, 5 Moderately Fatigued, and 10 Total Fatigue & Exhaustion3.3 score on a scaleStandard Error 0.25
p-value: 0.00495% CI: [-1.75, -0.38]Repeated measures linear model
Secondary

Surgeons' Cognitive Performance, Measured With the C3B Battery.

Surgeons' cognitive performance was assessed with the Cleveland Clinic Cognitive Battery (C3B, Cleveland, OH), a ten-minute-long self-administered computer tablet program that tests visual memory (episodic learning and delayed memory, range 0 - 70) and processing speed (information processing speed and incidental memory, range 40 - 120). Testing will take place right after surgery with surgeons still gowned. The surgeons will sit with the iPad touch screen placed on a desk in front of them for approximately 10 minutes to complete the cognitive test.

Time frame: Immediately after surgery, within 10 minutes

ArmMeasureGroupValue (MEAN)Dispersion
Cooling VestSurgeons' Cognitive Performance, Measured With the C3B Battery.C3B Processing Speed Test Score69.4 score on a scaleStandard Error 0.82
Cooling VestSurgeons' Cognitive Performance, Measured With the C3B Battery.C3B Visual Memory Test Score58.3 score on a scaleStandard Error 1.42
Without Cooling VestSurgeons' Cognitive Performance, Measured With the C3B Battery.C3B Processing Speed Test Score69.4 score on a scaleStandard Error 0.82
Without Cooling VestSurgeons' Cognitive Performance, Measured With the C3B Battery.C3B Visual Memory Test Score57.7 score on a scaleStandard Error 1.41
Comparison: C3B PST Scorep-value: 0.95595% CI: [-2.51, 2.38]Repeated measures linear model
Comparison: C3B VMT Scorep-value: 0.68695% CI: [-2.48, 3.71]Repeated measures linear model
Secondary

Surgeons' Perception and Amount of Sweat-soaked Scrub Clothing.

Immediately after surgery, while still gowned, surgeons' perception and amount of sweat-soaked scrub clothing will be rated using a Likert scale from 0 = not wet at all to 10 = fully drenched.

Time frame: Immediately after surgery, within 10 minutes

ArmMeasureValue (MEAN)Dispersion
Cooling VestSurgeons' Perception and Amount of Sweat-soaked Scrub Clothing.1.4 score on a scaleStandard Error 0.38
Without Cooling VestSurgeons' Perception and Amount of Sweat-soaked Scrub Clothing.4.4 score on a scaleStandard Error 0.38
p-value: <0.00195% CI: [-3.8, -2.13]Repeated measures linear model

Source: ClinicalTrials.gov · Data processed: Feb 9, 2026