Perioperative Hypothermia Hypothermia in Ambulatory Surgery

Perioperative Hypothermia Hypothermia in Ambulatory Surgery by Self-warming or Forced-air Warming Blanket, a Randomised Controlled Trial

The purpose of the study is to measure patient- temperature in the perioperative period of patients undergoing plastic surgery in an ambulatory surgical unit. This study will evaluate if active warming with self-warming blanket (Easywarm®) is as effective as active warming with forced-air blanket (BairHugger®). Second the study will evaluate if one or both methods is effective in preventing perioperative hypothermia.

Study Overview

• Status: Completed
• Conditions: Perioperative/Postoperative Complications
• Intervention / Treatment: Device: Easywarm; Device: BairHugger

Detailed Description

Background:

Anesthesia medicaments given in general anesthesia cause impaired thermoregulation and thermogenesis. After induction of general anesthesia the core temperature is reduced to redistribution of blood from the body core to the cooler skin. Later impaired thermogenesis contributes to further loss of heat.

Mild hypothermia (<36 degrees Celsius) contributes to increased incidence of wound infections, prolonged stay in the post anesthesia care unit, shivering and reduced patient comfort.

There are several effective interventions to prevent hypothermia such as active warming pre-, per- and postoperatively. Preheated intravenous fluids and medical interventions to alter the blood distribution from the periphery to the body core have been effective in preventing hypothermia.

In the department both self-warming blanket (Easywarm®) and forced-air blanket (BairHugger®) are routinely used to prevent hypothermia. It has been observed that a few patients undergoing plastic surgery with anesthesia time more than one hour are shivering and feeling cold in the postoperative period.

Purpose:

The purpose of the study is to observe and measure patient- temperature in the perioperative period of patients undergoing plastic surgery in an ambulatory surgical unit. This study will evaluate if active warming with self-warming blanket (Easywarm®) is as effective as active warming with forced-air blanket (BairHugger®). Second the study will evaluate if one or both methods is effective in preventing perioperative hypothermia.

Design:

The is a quality assurance study deigned as a prospective randomised trial. With a validated non-invasive termometer (SpotOn® 3M) temperature is measured before, during and after surgical procedures in general anesthesia. An equal number of notes with the number 1 and 2 were put into an envelope (1=EasyWarm®, 2=BairHugger®). For each operation theater a note is drawn, and all patients in that operation theater receives active warming according to the number on the note.

Population data:

Sex, age , weight, height, BMI, medication, morbidities and ASA class will be registered.

Measurements:

• temperature (Celsius)
• Blood pressure
• Heartrate
• SaO2
• Temperature-comfort "numeric rating scale" (NRS)

Other registrations:

• Medicines given during the study period.
• Start and end of anesthesia and surgery
• Time when temperature is above or eual to 36 degrees Celsius.
• Time when the patient go home

Data is collected and registered on a dataform. Data are analysed in a anonymized excel workbook.

• Study Type: Observational
• Enrollment (Actual): 112

Contacts and Locations

Study Locations

• Norway
  • Sør-Trøndelag
    • Trondheim, Sør-Trøndelag, Norway, 7014
      • Aleris Solsiden

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients planned for plastic surgery with planned total anestesia for more than 60 minutes are enrolled consecutively.

Description

Inclusion Criteria:

• Patients for planned plastic surgery with duration of general anesthesia ≥ 60 minutes.

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Easywarm; Self warming blanket to prevent perioperative hypothermia	Device: Easywarm; Warming blanket
BairHugger; Forced-air warming blanket to prevent perioperative hypothermia	Device: BairHugger; Patient warming mattress with continuous warm air.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Temperature	Temperature Celsius measured by SpotOn 3M	Perioperative period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Medication given during study period	Type and dosage is registered. Ephedrine and phenylephrine are known to interact with temperature regulation.	Perioperative period
Temperature Numerical Rating Scale	To identify at which temperature the patient is comfortably warm without need for warming intervention.	Perioperative period.

Collaborators and Investigators

• Sponsor: Aleris Helse
• Investigators: Principal Investigator: Stig S Tyvold, MD PhD, Aleris Helse AS

Publications and helpful links

General Publications

• Tyvold SS. Preventing hypothermia in outpatient plastic surgery by self-warming or forced-air-warming blanket: A randomised controlled trial. Eur J Anaesthesiol. 2019 Nov;36(11):843-850. doi: 10.1097/EJA.0000000000001087.

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2016
• Primary Completion (Actual): June 1, 2016
• Study Completion (Actual): June 1, 2016

Study Registration Dates

• First Submitted: March 2, 2016
• First Submitted That Met QC Criteria: May 21, 2017
• First Posted (Actual): May 23, 2017

Study Record Updates

• Last Update Posted (Actual): May 23, 2017
• Last Update Submitted That Met QC Criteria: May 21, 2017
• Last Verified: May 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Body Temperature Changes; Postoperative Complications; Hypothermia
• Other Study ID Numbers: 2015/1481

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No