What Is the Treatment of Carbon Monoxide Poisoning?
Carbon monoxide (CO) poisoning demands immediate action. Standard pulse oximetry is unreliable in this setting — treatment must begin at the point of suspicion, before laboratory confirmation is available.
Clinical Scenario
This protocol addresses the acute management of suspected or confirmed CO poisoning. The central objective is reversing carboxyhaemoglobin (COHb) accumulation through sustained delivery of oxygen at the highest achievable concentration, tailored to the patient's airway status and clinical condition.
Treatment Approach
The primary intervention is high-concentration oxygen, started immediately regardless of SpO₂ readings. Delivery may be non-invasive or invasive, with the route determined by the patient's condition and adequacy of protective reflexes.
Treatment Goals
Treatment continues until COHb normalises to below 3% and the patient is fully symptom-free. Under 100% oxygen, this is typically achievable within a maximum of five physiological half-lives — approximately 375 minutes.
References
- If CO poisoning is suspected, 100% oxygen or ventilation should be started immediately.
- Regardless of the oxygen saturation (SpO2), oxygen should be administered immediately at the highest possible concentration.
- Mask continuous positive airway pressure (CPAP) (non-invasive ventilation, NIV) or Demand valve or Constant dosing (high-flow) via tight-fitting mask with reservoir bag or Invasively using appropriate airway protection if protective reflexes are inadequate.
- There is strong evidence both in case reports and in several prospective studies that CPAP therapy at 5–12 mbar significantly shortens the half-life of COHb.
- Treatment must be continued until the COHb level has dropped to normal values (<3%) and the patient is symptom-free.
- This is typically achieved after a maximum of five physiological half-lives for COHb at 100% oxygen breathing (approximately 375 min).