Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 38-26: Carbon Monoxide Poisoning + Key Features Download Section PDF Listen +++ ++ Avidly binds to hemoglobin, which results in reduced oxygen-carrying capacity and altered delivery of oxygen to cells + Clinical Findings Download Section PDF Listen +++ ++ At low carbon monoxide levels (carboxyhemoglobin [COHb] 10–20%) Headache Dizziness Abdominal pain Nausea With somewhat higher levels (COHb 20–50%) Confusion Dyspnea Syncope With high levels (COHb > 50–60%) Hypotension Coma Seizures Permanent neurologic or neuropsychiatric deficits may develop in survivors of acute severe poisoning + Diagnosis Download Section PDF Listen +++ ++ Suspect in the setting of severe headache or acutely altered mental status, especially if multiple victims Diagnosis depends on Specific measurement of the arterial or venous COHb saturation However, the level may have declined if high-flow oxygen therapy has already been given COHb levels do not always correlate well with clinical findings Routine arterial blood gas testing and pulse oximetry are not useful because they may give falsely normal PaO2 or oxygen saturation levels + Treatment Download Section PDF Listen +++ ++ Remove victim from exposure Administer 100% oxygen by tight-fitting high-flow reservoir face mask or endotracheal tube Hyperbaric oxygen (HBO) Can provide 100% oxygen in higher than atmospheric pressures, further shortening the half-life May also reduce incidence of subtle neuropsychiatric sequelae Indications for HBO treatment after acute carbon monoxide exposure Loss of consciousness Metabolic acidosis COHb > 25% Age > 50 yr Cerebellar findings on neurologic examination