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Carbon Monoxide (CO)


Self harm is often evident but otherwise you may only be alerted to CO as a cause for headache due to the circumstances of the patient.  Be aware if other patients present from the same place. Living in a confined space, use of gas for cooking and heating for example may alert you.


History of exposure:

  • Self harm

  • Industrial

  • Recreational

  • Domestic

  • Carboxyhaemoglobin levels may still be high, discuss concerns with local toxicologist

  • If fire in an enclosed space - think cyanide poisoning - from plastic furniture, vinyl

  • Remember - unreliable pulse oximetry with CO


  • Primary survey, ABCDE approach and immediate resuscitation in systems, including oxygen, IV analgesia and fluids

  • O2 - high flow via non-rebreather mask

  • Supportive treatment and consult on local hyperbaric practices

  • Treat comorbidities


  • Admission as indicated by condition

  • Follow up by GP and specialists for neuropsychiatric testing for discharged patients

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