Evaluating Adult Patient Temperatures During Lower Spinal Surgery

• ClinicalTrials.gov Identifier: NCT03050775
• Recruitment Status: Completed
• First Posted: February 13, 2017
• Results First Posted: May 7, 2018
• Last Update Posted: May 7, 2018
• Sponsor: Mayo Clinic
• Collaborator: Westmed, Inc.
• Information provided by (Responsible Party): Jean M. Guyer, Mayo Clinic

Study Description

Brief Summary:

The purpose of this study is to evaluate patients' temperatures after using one of two ventilator circuits (breathing systems): the ANAPOD™ Heat and Humidification System (ANAPOD™ system) or the standard ventilator circuit with a heat-moisture exchanger (standard ventilator). The ANAPOD™ system will provide additional heat and humidity to patients through their breathing tube while the standard ventilator will not. The investigators are doing this research study to find out if the ventilator circuit providing additional heat and humidity will keep patients warmer during surgery and after surgery.

Condition or disease	Intervention/treatment	Phase
Hypothermia	Device: Heated Ventilator Circuit; Device: Standard Ventilator Circuit	Not Applicable

Detailed Description:

Patients were randomly assigned to either the treatment group or the control group prior to surgery. Prior to induction, patients in the control group were given inspiratory gas at ambient air temperature (20-22 degrees Celsius) and patients in the treatment group were given inspiratory gas at warmed temperatures (40-41 degrees Celsius). All patients were induced with general anesthesia in the supine position and repositioned prone following endotracheal intubation and placement of an esophageal stethoscope with a temperature sensor, as per usual hospital practice. Esophageal temperatures were recorded within 30 minutes of the baseline esophageal temperature and every 10 minutes thereafter for the first hour post-induction. All patients had a blanket and forced air warming applied to their lower extremities and upper back at 43 degrees Celsius after draping. All patients had esophageal temperature measurements recorded every 30 minutes until the patient was repositioned supine. Core temperatures were recorded four hours post-induction for those patients reaching that timeframe.

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 70 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Intervention Model Description: randomized, trial (treatment or no treatment)
• Masking: Double (Participant, Outcomes Assessor)
• Masking Description: Patients were randomly assigned to either the treatment group or the control group prior to surgery. Group randomization was performed using a randomization schedule prepared by the Division of Clinical Statistics with patients randomized in blocks of four. For consented and enrolled patients on the day of surgery in the admit areas, a participant was assigned the next sequential participant ID number and the appropriate sealed envelope was opened to reveal the participant's randomized intervention. This occurred before the patient was transferred to the operating suite. Individuals who performed data analysis were blinded to treatment group.
• Primary Purpose: Prevention
• Official Title: Comparing Patient Temperatures in Adults During Lower Spinal Surgery Using Either a Heated Ventilator Circuit or a Standard Ventilator Circuit With a Heat-Moisture Exchanger
• Actual Study Start Date: August 28, 2015
• Actual Primary Completion Date: February 5, 2017
• Actual Study Completion Date: February 5, 2017

Arms and Interventions

Arm	Intervention/treatment
Experimental: Heated Ventilator Circuit; Heated and humidified inspired gases using the ANAPOD™ Heat and Humidification System (Westmed; Tucson, Arizona, USA) circuit prior to induction of general anesthesia in addition to standard ventilation and temperature management.	Device: Heated Ventilator Circuit; active heat and humidification during anesthesia by warming inspire gases without a heat-moisture exchanger; Other Name: ANAPOD™ Heat and Humidification System
Active Comparator: Standard Ventilator Circuit; Standard ventilation and temperature management.	Device: Standard Ventilator Circuit; no active heat and humidification during anesthesia; Other Name: Thermovent 600; Portex

Outcome Measures

Primary Outcome Measures :

1. Core Body Temperature [ Time Frame: Approximately four hours post-induction of general anesthesia (or last recorded temperature) ]
   Core body temperature will be taken in the esophagus. The last recorded esophageal temperature will be used for surgeries not reaching 3 hours duration.

Secondary Outcome Measures :

1. Intraoperative Core Temperatures Post-induction [ Time Frame: Approximately 30 minutes, 60 minutes, 120 minutes post-induction of general anesthesia ]
   Core body temperature will be taken in the esophagus after general anesthesia induction.
2. Number of Subjects With Post-operative Shivering [ Time Frame: Approximately 2 hours after completion of the surgery ]
   Shivering in the post-anesthesia care unit will be assessed using the Bedside Shivering Assessment Scale. This is a 4 point scale and rate shivering as the following: absent, mild, moderate, or severe. Only the highest degree of patient shivering was used in the analysis.
3. Hospital Length of Stay [ Time Frame: Surgery to hospital discharge ]
   Number of days in the hospital
4. Overall Post-operative Temperature [ Time Frame: PACU arrival ]
   Temperature at Post Anesthesia Care Unit (PACU) arrival.
5. Number of Participants With Transfusion Within 48 Hours of Surgery [ Time Frame: Within 48 hours of surgery ]
   Requirement of blood transfusion within 48 hours of surgery
6. Estimated Blood Loss [ Time Frame: duration of surgery ]
   The estimated blood loss per case was determined by the anesthesia provider by measuring the volume of blood in the suction canister while taking into account the amount of irrigation solution used.

Eligibility Criteria

• Ages Eligible for Study: 18 Years and older (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

• Elective spine surgery anticipated greater than three hours in duration
• Posterior approach
• An operative site between lumbar one and sacral one
• Involving two or more levels with fusion and/or instrumentation and/or revisions
• American Society of Anesthesiologists (ASA) Status of I-III

Exclusion Criteria:

• Patients with a tracheostomy
• Preoperative temperature >38°C or <36°C on the day of surgery
• Active infection or erythema to the back
• White blood cell count greater than 10,500/microliter (mcL)

Contacts and Locations

Sponsors and Collaborators

Mayo Clinic

Westmed, Inc.

Investigators

• Principal Investigator: Jean M Guyer, DNP; Mayo Clinic

  Study Documents (Full-Text)

Documents provided by Jean M. Guyer, Mayo Clinic:

Study Protocol and Statistical Analysis Plan  [PDF] October 26, 2015

More Information

• Responsible Party: Jean M. Guyer, Principal Investigator, Mayo Clinic
• ClinicalTrials.gov Identifier: NCT03050775
• Other Study ID Numbers: 15-001604; UL1TR000135 ( U.S. NIH Grant/Contract )
• First Posted: February 13, 2017
• Results First Posted: May 7, 2018
• Last Update Posted: May 7, 2018
• Last Verified: May 2018

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Product Manufactured in and Exported from the U.S.: Yes

Additional relevant MeSH terms:

Hypothermia; Body Temperature Changes