Carbon Monoxide Monitoring and Emergency Treatment (COMET)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00841165
Recruitment Status : Unknown
Verified April 2010 by University of Vermont.
Recruitment status was:  Recruiting
First Posted : February 11, 2009
Last Update Posted : April 2, 2010
Information provided by:
University of Vermont

Brief Summary:
Carbon monoxide (CO) has been called a "silent killer", and those patients who survive CO poisoning are at risk of neurological damage, which may be permanent. CO is a leading cause of unintentional poisoning deaths in the United States, and the odorless gas results in an estimated average of 20,636 emergency department (ED) visits each year. Oxygen is the antidote for CO poisoning, and it acts both by attenuating toxic effects and enhancing elimination. A fractional inspired concentration of oxygen (FiO2) of 0.7 to 0.9 may be achieved by administration of 100% oxygen delivered using a reservoir with a facemask that prevents rebreathing. Hyperbaric oxygen therapy may provide added benefit for patients with CO poisoning, but this therapy is unavailable in many parts of the United States including Vermont. Use of a continuous positive airway pressure (CPAP) mask may achieve an FiO2 of 1.0, but the effects of delivering an FiO2 of 1.0 compared to 0.7 in CO poisoning are unknown. CPAP, by comparison, is inexpensive, portable, and available in most EDs. In this study, the investigators are testing the hypothesis that oxygen delivered by CPAP will improve both CO washout kinetics and functional outcomes, compared to the standard therapy of oxygen delivered by non-rebreathing facemask. Specific Aim 1 will provide toxicokinetic data to support a potential benefit in the use of CPAP for CO poisoning, by comparing CO elimination kinetics in response to oxygen therapy delivered by non-rebreathing facemask versus CPAP. The 20 patients expected in our first year will provide adequate power to detect a 20% fall in half-time of CO elimination. While CPAP may increase CO washout rates, as predicted in Specific Aim 1, demonstration of real functional benefit will be tested in Specific Aim 2. This Aim seeks to determine functional (neuropsychological) outcomes in patients with CO poisoning treated with oxygen therapy delivered by non-rebreathing facemask versus CPAP. Data showing a therapeutic benefit from CPAP in CO poisoning would have clinical implications. Compared to hyperbaric oxygen therapy, CPAP therapy can begin earlier, including the pre-hospital setting, for patients with known exposure. With the frequent nature of CO poisoning and the widespread availability of CPAP, a potential benefit could lead to improved outcomes for the 20,000+ patients who present to EDs annually.

Condition or disease Intervention/treatment Phase
Carbon Monoxide Poisoning Device: Continuous Positive Airway Pressure Device: Non-rebreather oxygen mask Not Applicable

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 40 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Randomized Trial of Carbon Monoxide Elimination Kinetics With Oxygen Delivered by Continuous Positive Airway Pressure Compared to Face Mask
Study Start Date : January 2009
Estimated Primary Completion Date : June 2010
Estimated Study Completion Date : June 2010

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: 1
Participants in this arm are treated with Continuous Positive Airway Pressure at 5cm H2O and 100% oxygen
Device: Continuous Positive Airway Pressure
Full face CPAP at 5cm H2O and 100% oxygen

Active Comparator: 2
Participants in this arm receive standard of care therapy- oxygen via a non-rebreather mask
Device: Non-rebreather oxygen mask
Oxygen administered through a non-rebreather mask

Primary Outcome Measures :
  1. Half life of Carboxyhemoglobin [ Time Frame: Every 15 minutes during treatment ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Elevated Carboxyhemoglobin Level (non-smokers >8%, smokers >12%)
  • 18 years of age or older
  • Able to provide informed consent as assessed by Attending Emergency Physician

Exclusion Criteria:

  • Requires daily medication for active lung disease
  • Altered mental status
  • Hemodynamically unstable
  • Requires transfer to ICU or hyperbaric oxygen facility
  • Previous enrollment in the study
  • No concurrent acute psychiatric illness

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00841165

Contact: Tyler J Lemay, BFA
Contact: Kalev Freeman, MD PhD

United States, Vermont
Fletcher Allen Health Care Recruiting
Burlington, Vermont, United States, 05401
Principal Investigator: Tyler J Lemay, BFA         
Sponsors and Collaborators
University of Vermont
Study Director: Kalev Freeman, MD, PhD University of Vermont

Responsible Party: Dr. Kalev Freeman, Faculty Sponsor, Department of Surgery, University of Vermont Identifier: NCT00841165     History of Changes
Other Study ID Numbers: CHRMS 09-056
First Posted: February 11, 2009    Key Record Dates
Last Update Posted: April 2, 2010
Last Verified: April 2010

Keywords provided by University of Vermont:
Carbon Monoxide Toxicity

Additional relevant MeSH terms:
Carbon Monoxide Poisoning
Chemically-Induced Disorders
Gas Poisoning
Carbon Monoxide
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Physiological Effects of Drugs