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TerminatedNCT04776954Updated Sep 27, 2024Results posted

Warming Blanket Comparison Study

An interventional study of Forced Air Warming System and Resistive Blanket Warming System in Surgery and Temperature Change, Body, sponsored by University of Minnesota. Terminated at 1 site in United States. Open to participants aged 18 Years to 90 Years. Per ClinicalTrials.gov, last updated 2024-09-27.

Sponsored by University of Minnesota · Not applicable, Interventional, and Basic science

Why this study was terminated
PI left institution, no new PI available
Phase
Not applicable
Study type
Interventional
Enrollment
15
Allocation
Randomized
Ages
18 Years to 90 Years
Sex
All
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Study summary

The purpose of the study is to compare the effectiveness of resistive blanket warming to forced air warming in maintaining body temperature in participants undergoing renal transplantation.

Read the detailed description

The study will involve two arms: a resistive blanket warming system arm and a forced air warming system arm. Both devices will be set to warm the participant at a standard 41 degrees Celsius when the participant is to be rewarmed.

During the study, the forced air warming system (FAWS) will be placed on the (resistive blanket warming system (RBWS), with the participant laying on top of the forced air warming system. The arm components will be wrapped around the participant's arms to assist with patient positioning for surgery. Both the forced air and resistive blanket warming systems will be attached to their respective heating units before the participant is brought to the OR and transferred to the operating room table. After the needed standard monitors for surgery have been placed, general anesthesia will be induced and maintained with participant's hemodynamics and other vitals maintained per standard care (no additional measurements beyond standard of care which is recorded in EPIC). The certified registered nurse anesthetists (CRNA) will be involved in the placement of the blankets. Operating Room Nurse managers and CRNA's will be informed by research team regarding participant's involvement in the study.

Participant's core temperature will be measured with a nasopharyngeal temperature probe. Vital signs, including continuous blood pressure, heart rate, oxygen saturation, and end-tidal carbon dioxide, will be monitored and recorded in Epic as is routine with all anesthetics performed.

Standard anesthetic care of the participant will occur for the duration of the surgery. The participant will be randomized to either the FAWS or RBWS before arrival to the operating room. The participant's temperature will be monitored and recorded for the duration of surgery with the selected warming system. The primary outcome variable is the nasopharyngeal temperature as recorded at the end of the surgery.

Temperature measurement in the PACU will be standardized with skin temperature probes that will be placed on the forehead prior to leaving the operating room.

02

Conditions studied

  • Surgery
  • Temperature Change, Body
03

In context

Body Temperature Changes

97 studies on the registry are indexed under Body Temperature Changes; 20 are open to participants now.

This study's enrollment of 15 is below the median of 40 across 68 interventional studies indexed under Body Temperature Changes.

Browse Body Temperature Changes studies →

Lead sponsor

University of Minnesota is the lead sponsor of 1,216 studies on the registry; 197 are open to participants now.

Of its 136 completed or terminated interventional studies of FDA-regulated products, 95 (70%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 90 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Undergoing elective renal transplantation

Exclusion criteria

Exclusion Criteria:

  • Previous surgery involving organ transplantation or nephrectomy. These patients are at higher risk of blood loss, making temperature regulation subject to more variables outside our control.
  • End stage renal disease with decreased or no urine output from normal. Bladder temperature will not be valid in these patients.
  • Previous upper extremity amputations
  • Ongoing sepsis or other infection
  • Thyroid dysfunction
  • Emergency surgery
  • Refusal of consent to participate in study
  • Pregnancy
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
15 participants (actual)

Study arms

  • Active comparator
    Forced Air Warming System

    Participants in this arm will receive warming using a forced air warming system.

    Device: Forced Air Warming System

  • Active comparator
    Resistive Blanket Warming System

    Participants in this arm will receive warming using a resistive blanket warming system.

    Device: Resistive Blanket Warming System

Interventions

  • DeviceForced Air Warming System

    The forced air warming system has a heater unit that blows air through a conduit to an "air blanket" that inflates with forced air that circulates throughout the blanket, and exits through tiny perforations on the patient-side of that blanket. The heat primarily warms the subject through convective means. As the warmed air escapes through the perforations in the blanket, it creates an environment of continuously circulating warm air that is in contact with the skin.

  • DeviceResistive Blanket Warming System

    This blanket is equivalent to an operating-room-safe electric blanket. Through a power cord, a separate power source powers a semiconductor layer within the resistive blanket to generate heat. The heat primarily warms the subject by conductive warming through direct skin contact, and, secondarily, by warming the air around the participant in areas where there is no direct skin contact.

06

What researchers measure

Primary outcomes

  1. AUC of Temperature vs Time

    Outcome is reported as the Area Under Curve (AUC) of temperature vs time curve during hypothermia (core temperature less than 36 degrees Celcius) during the duration of surgery. Unit of measure is degrees Celsius per minute. Time during surgery spent under 36 degrees Celsius through comparison of nasopharyngeal temperature, which is measured by placing a nasopharyngeal temperature probe 10 to 20 cm into the nare, between forced air warming system (FAWS) and resistive blanket warming system (RBWS).

    Time frame: up to 5 hours

Secondary outcomes

  1. Body Temperature Upon Arrival in PACU

    Outcome is reported as the body temperature recorded upon arrival in post-anesthesia care unit (PACU).

    Time frame: up to 2 hours

07

Results

Posted Sep 27, 2024

Participant flow

Participant flow — Overall Study
MilestoneForced Air Warming SystemResistive Blanket Warming System
Started78
Completed78
Not completed00

Outcome measures

PrimaryAUC of Temperature vs Time

Outcome is reported as the Area Under Curve (AUC) of temperature vs time curve during hypothermia (core temperature less than 36 degrees Celcius) during the duration of surgery. Unit of measure is degrees Celsius per minute. Time during surgery spent under 36 degrees Celsius through comparison of nasopharyngeal temperature, which is measured by placing a nasopharyngeal temperature probe 10 to 20 cm into the nare, between forced air warming system (FAWS) and resistive blanket warming system (RBWS).

Time frame:
up to 5 hours
Reported as:
Mean · celsius per minute
AUC of Temperature vs Time
celsius per minuteForced Air Warming SystemResistive Blanket Warming System
AUC of Temperature vs Time-131 ± 93-147 ± 69
SecondaryBody Temperature Upon Arrival in PACU

Outcome is reported as the body temperature recorded upon arrival in post-anesthesia care unit (PACU).

Time frame:
up to 2 hours
Reported as:
Mean · celsius per minute
Body Temperature Upon Arrival in PACU
celsius per minuteForced Air Warming SystemResistive Blanket Warming System
Body Temperature Upon Arrival in PACU36.8 ± 0.537 ± 0.3

Adverse events

Collected over No adverse event were reported. The study participants were only on the study for the time of warming blanket and was very minimal risk.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Forced Air Warming System———
Resistive Blanket Warming System———

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Forced Air Warming SystemResistive Blanket Warming SystemTotal
<=18 years000
Between 18 and 65 years5611
>=65 years224
Sex: Female, Male
Sex: Female, Male(Participants)Forced Air Warming SystemResistive Blanket Warming SystemTotal
Female145
Male6410
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Forced Air Warming SystemResistive Blanket Warming SystemTotal
Hispanic or Latino000
Not Hispanic or Latino6612
Unknown or Not Reported123
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Forced Air Warming SystemResistive Blanket Warming SystemTotal
American Indian or Alaska Native000
Asian101
Native Hawaiian or Other Pacific Islander000
Black or African American011
White6713
More than one race000
Unknown or Not Reported000
08

Study locations

1 site
  • University of Minnesota
    Minneapolis, Minnesota 55455, United States
09

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

10

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Sep 2021 to primary completion in Nov 2022, 13 months.

Results were first posted in Sep 2024, 1 year 10 months after primary completion.

How these figures are worked out, and which studies are left out of them.

Registered
Feb 25, 2021
First posted
Mar 2, 2021
StartActual
Sep 27, 2021
Primary completionActual
Nov 17, 2022
CompletionActual
Nov 17, 2022
Results first posted
Sep 27, 2024
Last update
Sep 27, 2024
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Sep 27, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT04776954
Responsible party
Sponsor
First posted
Mar 2, 2021
Start date
Sep 27, 2021
Primary completion
Nov 17, 2022
Completion
Nov 17, 2022
Results posted
Sep 27, 2024
Last update
Sep 27, 2024

Study contacts

Cole Bennett, MD
principal investigator · University of Minnesota

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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