Intraoperative Warming Comparison of Devices

Intraoperative Warming : Comparison of Performance of the Dynatherm Medical vitalHEAT™ Temperature Management System (vH2) and the Arizant Bair Hugger System

Hypothermia is a common and serious complication during anesthesia and surgery. Anesthetic-induced hypothermia results from the inhibition of thermoregulatory control and exposure to cold operating room environment.

Various warming methods, such as warm blankets, forced-air warmers and circulating water mattresses, are currently used to prevent and treat mild perioperative hypothermia. All are cutaneous approaches that rely on heating the peripheral tissues in order to increase the thermal core temperature. Application of cutaneous warming system blankets/pads are limited by location/extent of operative site; for example, in certain procedures such as laparatomies, reconstructive plastic surgery or orthopedic surgery, only a limited amount of skin surface is available for warming application. The Dynatherm vitalHEAT technology takes advantage of the body's natural thermoregulatory system to channel thermal energy to the body's core non-invasively at a rapid rate. The vital heat (vH2) system is designed to treat hypothermia during the peri-operative period through a combination of localized heat and vacuum application to one hand & forearm; this application 1) opens the arteriovenous anastamoses located in the palm of the hand and 2) conductively warms the extremity thus effectively warming the blood flow to the body's core. The vital heat vH2 system is a portable and compact warming device which provides a non-invasive approach to warming patients during surgery.

The primary objective of this study is to determine if the Dynatherm Medical vitalHEAT (vH2) Temperature Management System is as effective as the forced-air warming Bair Hugger™ (Arizant Healthcare, Eden Prairie, MN) for maintenance of intraoperative body temperature in patients undergoing abdominal surgery under general anesthesia. The critical endpoints to be evaluated in making this determination are 1) % of subjects with an average intraoperative esophageal temperature of ≥ 36º C and 2) % of subjects with an initial post anesthesia care unit sublingual temperature of ≥ 36º C. Secondary objectives include 1) comparison of the core body temperatures @ 60 minutes post anesthesia induction, 2) comparison of temperature trends during surgery and 3) comparison of the subjects' post anesthesia care unit temperature trends and hypothermic symptoms such as shivering.

Study Overview

• Status: Completed
• Conditions: Hypothermia
• Intervention / Treatment: Device: Dynatherm Medical vitalHEAT Temperature Management System vH2; Device: Bair Hugger™ (Arizant Healthcare, Eden Prairie, MN)

• Study Type: Interventional
• Enrollment (Actual): 42
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Florida
    • Tampa, Florida, United States, 33606
      • Tampa General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients undergoing elective open abdominal surgical procedures with an expected duration of 2 to 4 hours and requiring general anesthesia
• American Society of Anesthesiologists(ASA) physical status I-III
• Patient age: > 18 years and <80 years

Exclusion Criteria:

• Patient age: < 18 years and >80 years
• Patients with break in skin integrity on the extremity selected as the application site
• Patients with history of upper extremity peripheral vascular disease
• Patients with history of allergic skin conditions of the upper extremities
• Patients with history of bleeding disorders/coagulopathy
• Patient with history of malignant hyperthermia
• Patients who are pregnant
• Patient unwilling or unable to give informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: vH2 System Group; The vital heat vH2 system consists of a Control Unit containing the heating system and the vacuum generation pump which connects via an umbilical containing the fluid and vacuum tubing to the Warming Sleeve. The Control Unit also contains the user interface and alarm management systems. The disposable Warming Sleeve consists of a manifold attached to the warming pads and a polyurethane pouch (Vacuum Sleeve) that are placed over the patient's hand and forearm and secured with tape. The Warming Sleeve manifold contains connectors for the fluid and vacuum tubing contained in the umbilical. The vital heat vH2 System will be used for patient warming during these surgical procedures. Monitoring of core temperature via esophageal probe will be done for the purpose of data collection.	Device: Dynatherm Medical vitalHEAT Temperature Management System vH2; The vH2 system consists of a Control Unit containing the heating system and the vacuum generation pump which connects via an umbilical containing the fluid and vacuum tubing to the Warming Sleeve. The Control Unit also contains the user interface and alarm management systems. The disposable Warming Sleeve consists of a manifold attached to the warming pads and a polyurethane pouch (Vacuum Sleeve) that are placed over the patient's hand and forearm and secured with tape. The Warming Sleeve manifold contains connectors for the fluid and vacuum tubing contained in the umbilical.; Other Names: Part number VH-200
ACTIVE_COMPARATOR: Control Group; The Bair Hugger system is the current standard of care at Tampa General Hospital. It consists of a Temperature Management Unit that contains the heating element, the air circulating motor and the temperature control mechanisms. This unit connects via a hose to the operating room blankets. The Bair Hugger technology relies on heated air convection. Warm air is circulated evenly through the air space in the specially designed blanket, warming the skin surface as well as any insulating blankets placed over the Bair Hugger blanket. The Bair Hugger System is the site's current approach to patient warming during these surgical procedures. Monitoring of core temperature via esophageal probe will be done for the purpose of data collection.	Device: Bair Hugger™ (Arizant Healthcare, Eden Prairie, MN); The Bair Hugger system is the current standard of care at Tampa General Hospital. It consists of a Temperature Management Unit that contains the heating element, the air circulating motor and the temperature control mechanisms. This unit connects via a hose to the operating room blankets. The Bair Hugger technology relies on heated air convection. Warm air is circulated evenly through the air space in the specially designed blanket, warming the skin surface as well as any insulating blankets placed over the Bair Hugger blanket.; Other Names: Model 522

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent of Patients With an Average Intraoperative Temperature Greater Than or Equal to 36 Celcius		Intraoperative Period
Percent of Subjects With an Initial PACU Sublingual Temperature of ≥ 36º C.		Temp taken just prior to surgery
Percentage of Patients With a Post Operative Sublingual Temperature Above 36 Degrees Celcius	Percent of subjects with an initial post anesthesia care unit sublingual temperature of ≥ 36º C	Upon entry to the post anesthesia care unit

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of the Core Body Temperatures at 60 Minutes Post Anesthesia Induction,as Assessed by Esophageal Probe.	Average core body temperature measured with an esophageal probe at 60 minutes post-induction	60 minutes post anesthesia induction
Average Intraoperative Esophageal Temperature	Average esophageal temperature for the first 70 minutes of surgery following induction of anesthesia.	Intraoperative 0-70 minutes
Median Post Anesthesia Care Unit Sublingual Temperature		Upon arrival to the post anesthesia care unit

Collaborators and Investigators

• Sponsor: University of South Florida
• Collaborators: Dynatherm Medical Inc.
• Investigators: Principal Investigator: Enrico M Camporesi, M.D., University of South Florida

Publications and helpful links

General Publications

• Sessler DI. Perioperative heat balance. Anesthesiology. 2000 Feb;92(2):578-96. doi: 10.1097/00000542-200002000-00042.
• Insler SR, Sessler DI. Perioperative thermoregulation and temperature monitoring. Anesthesiol Clin. 2006 Dec;24(4):823-37. doi: 10.1016/j.atc.2006.09.001.
• Giesbrecht GG, Ducharme MB, McGuire JP. Comparison of forced-air patient warming systems for perioperative use. Anesthesiology. 1994 Mar;80(3):671-9. doi: 10.1097/00000542-199403000-00026.
• Taguchi A, Ratnaraj J, Kabon B, Sharma N, Lenhardt R, Sessler DI, Kurz A. Effects of a circulating-water garment and forced-air warming on body heat content and core temperature. Anesthesiology. 2004 May;100(5):1058-64. doi: 10.1097/00000542-200405000-00005.

Study record dates

Study Major Dates

• Study Start: February 1, 2009
• Primary Completion (ACTUAL): July 1, 2009
• Study Completion (ACTUAL): August 1, 2009

Study Registration Dates

• First Submitted: March 27, 2008
• First Submitted That Met QC Criteria: March 31, 2008
• First Posted (ESTIMATE): April 1, 2008

Study Record Updates

• Last Update Posted (ESTIMATE): October 29, 2012
• Last Update Submitted That Met QC Criteria: September 25, 2012
• Last Verified: September 1, 2012

More Information

Terms related to this study

• Keywords: anesthesia; hypothermia; body temperature; intraoperative warming
• Additional Relevant MeSH Terms: Body Temperature Changes; Hypothermia
• Other Study ID Numbers: IRB 106411c; TGH 100; USF 6176-P67639