Trial Outcomes & Findings for The Effects of Ambient Temperature and Forced-air Warming on Intraoperative Core Temperature (NCT NCT02715076)

Results Overview

Rate of core temperature change from 1 to 3 hours after induction of anesthesia (°C/hour ) linear mixed-effects model to assess the effects of ambient temperature, forced-air warming and their interaction on the rate of core temperature change during 1 to 3h after induction

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

292 participants

Primary outcome timeframe

from 1 to 3 hours after induction of anesthesia

Results posted on

2021-05-11

Participant Flow

Participant milestones

Participant milestones
Measure	Ambient Temp 19°C & Passive Insulation Ambient Temperature 19°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 19°C: Ambient Temperature 19°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 19°C & Forced-air Warming Ambient Temperature 19°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 19°C: Ambient Temperature 19°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.	Ambient Temp 21°C & Passive Insulation Ambient Temperature 21°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 21°C: Ambient Temperature 21°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 21°C & Forced-air Warming Ambient Temperature 21°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 21°C: Ambient Temperature 21°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.	Ambient Temp 23°C & Passive Insulation Ambient Temperature 23°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 23°C: Ambient Temperature 23°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 23°C & Forced-air Warming Ambient Temperature 23°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 23°C: Ambient Temperature 23°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.
Overall Study STARTED	48	50	49	50	47	48
Overall Study COMPLETED	48	50	49	50	47	48
Overall Study NOT COMPLETED	0	0	0	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Effects of Ambient Temperature and Forced-air Warming on Intraoperative Core Temperature

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Ambient Temp 19°C & Passive Insulation n=48 Participants Ambient Temperature 19°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 19°C: Ambient Temperature 19°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 19°C & Forced-air Warming n=50 Participants Ambient Temperature 19°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 19°C: Ambient Temperature 19°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.	Ambient Temp 21°C & Passive Insulation n=49 Participants Ambient Temperature 21°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 21°C: Ambient Temperature 21°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 21°C & Forced-air Warming n=50 Participants Ambient Temperature 21°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 21°C: Ambient Temperature 21°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.	Ambient Temp 23°C & Passive Insulation n=47 Participants Ambient Temperature 23°C and Passive Insulation: patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping. Ambient Temperature 23°C: Ambient Temperature 23°C Passive insulation: Patients assigned to passive insulation will be covered as usual with a cotton gown and single layer of cloth surgical draping.	Ambient Temp 23°C & Forced-air Warming n=48 Participants Ambient Temperature 23°C and Forced-air Warming: patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface. Ambient Temperature 23°C: Ambient Temperature 23°C Forced-air cover (Bair hugger 63500, 3M): Patients assigned to forced-air warming will also be covered with a gown and surgical drapes, but a forced-air cover (Bair hugger 63500, 3M) will be inserted between the gown and the skin surface.	Total n=292 Participants Total of all reporting groups
Age, Continuous	50 years STANDARD_DEVIATION 12 • n=5 Participants	54 years STANDARD_DEVIATION 12 • n=7 Participants	54 years STANDARD_DEVIATION 13 • n=5 Participants	57 years STANDARD_DEVIATION 11 • n=4 Participants	57 years STANDARD_DEVIATION 11 • n=21 Participants	54 years STANDARD_DEVIATION 12 • n=8 Participants	54 years STANDARD_DEVIATION 12 • n=8 Participants
Sex: Female, Male Female	29 Participants n=5 Participants	27 Participants n=7 Participants	24 Participants n=5 Participants	18 Participants n=4 Participants	22 Participants n=21 Participants	24 Participants n=8 Participants	144 Participants n=8 Participants
Sex: Female, Male Male	19 Participants n=5 Participants	23 Participants n=7 Participants	25 Participants n=5 Participants	32 Participants n=4 Participants	25 Participants n=21 Participants	24 Participants n=8 Participants	148 Participants n=8 Participants

PRIMARY outcome

Timeframe: from 1 to 3 hours after induction of anesthesia

Population: We plotted the mean core temperatures at 10-minute intervals. The trend of core temperature in each of the six groups between 1 to 3 hours was roughly linear. We thus used the slope (change in °C/hour) to characterize the rate sat which intraoperative core temperature changed.

Rate of core temperature change from 1 to 3 hours after induction of anesthesia (°C/hour ) linear mixed-effects model to assess the effects of ambient temperature, forced-air warming and their interaction on the rate of core temperature change during 1 to 3h after induction