Carbon Monoxide Monitoring and Emergency Treatment

NCT00841165 | Unknown DMC

• 1 other identifier: CHRMS 09-056
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

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.

Conditions

Carbon Monoxide Poisoning

Keywords

Carbon Monoxide Toxicity; Carbon; Monoxide; Poisoning; Toxicity; Treatment; CPAP; Hyperbaric; Oxygen

Outcome Measures

Primary Outcomes (1)

• Half life of Carboxyhemoglobin

  Every 15 minutes during treatment

Study Arms (2)

1

EXPERIMENTAL

Participants in this arm are treated with Continuous Positive Airway Pressure at 5cm H2O and 100% oxygen

Device: Continuous Positive Airway Pressure

2

ACTIVE COMPARATOR

Participants in this arm receive standard of care therapy- oxygen via a non-rebreather mask

Device: Non-rebreather oxygen mask

Interventions

Continuous Positive Airway Pressure DEVICE

Full face CPAP at 5cm H2O and 100% oxygen

1

Non-rebreather oxygen mask DEVICE

Oxygen administered through a non-rebreather mask

2

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

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

You may not qualify if:

• 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

Sponsors & Collaborators

• University of Vermont: lead

Study Sites (1)

Fletcher Allen Health Care

Burlington, Vermont, 05401, United States

RECRUITING

Related Publications (3)

• Bruce MC, Bruce EN. Analysis of factors that influence rates of carbon monoxide uptake, distribution, and washout from blood and extravascular tissues using a multicompartment model. J Appl Physiol (1985). 2006 Apr;100(4):1171-80. doi: 10.1152/japplphysiol.00512.2005. Epub 2005 Dec 8.

  PMID: 16339350 BACKGROUND

• Bruce EN, Bruce MC. A multicompartment model of carboxyhemoglobin and carboxymyoglobin responses to inhalation of carbon monoxide. J Appl Physiol (1985). 2003 Sep;95(3):1235-47. doi: 10.1152/japplphysiol.00217.2003. Epub 2003 May 16.

  PMID: 12754170 BACKGROUND

• Weaver LK. Clinical practice. Carbon monoxide poisoning. N Engl J Med. 2009 Mar 19;360(12):1217-25. doi: 10.1056/NEJMcp0808891. No abstract available.

  PMID: 19297574 BACKGROUND

MeSH Terms

Conditions

Carbon Monoxide Poisoning; Poisoning

Interventions

Continuous Positive Airway Pressure

Condition Hierarchy (Ancestors)

Gas Poisoning; Chemically-Induced Disorders

Intervention Hierarchy (Ancestors)

Positive-Pressure Respiration; Respiration, Artificial; Airway Management; Therapeutics; Respiratory Therapy

Study Officials

• Kalev Freeman, MD, PhD

  University of Vermont

  STUDY DIRECTOR

Central Study Contacts

Tyler J Lemay, BFA

CONTACT

tyler.lemay@uvm.edu

Kalev Freeman, MD PhD

CONTACT

kalev.freeman@uvm.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: February 10, 2009
• First Posted: February 11, 2009
• Study Start: January 1, 2009
• Primary Completion: June 1, 2010
• Study Completion: June 1, 2010
• Last Updated: April 2, 2010

Record last verified: 2010-04

Locations

US (1)