Carbon monoxide poisoning

Last revised by Ole Hensel on 25 Jun 2023

Carbon monoxide poisoning may result in an anoxic-ischemic encephalopathy, with acute as well as delayed effects.

Gas geyser syndrome is a term used to describe symptoms of carbon monoxide poisoning while bathing due to carbon monoxide production from liquefied petroleum gas geysers used to heat water 11.

Carbon monoxide poisoning is mostly preventable with common causes including malfunctioning heating systems, improperly ventilated motor vehicles, and residential fires 9. It is also observed as an attempt to commit suicide. 

Patients can present with 10:

The pathophysiology can be two-fold:

  • carbon monoxide strongly binds to hemoglobin and the resultant carboxyhemoglobin in the bloodstream can cause profound hypoxic/anoxic injury

  • carbon monoxide is also a respiratory chain metabolism toxin that interferes with mitochondrial oxidative phosphorylation and activates polymorphonuclear leukocytes, which undergo diapedesis and cause brain lipid peroxidation; this results in the delayed effects of carbon monoxide poisoning

Changes tend to be bilateral with the globus pallidus most commonly affected 2

Classically seen as low attenuation in the globus pallidus region. Other features include diffuse hypoattenuation in cerebral white matter 4.

Regions of involvement are similar to CT. Signal characteristics include:

  • T1: affected areas are usually low signal, hemorrhagic areas can be high signal

  • T2/FLAIR: affected areas are high signal

  • T1 C+ (Gd): can show patchy peripheral enhancement in affected areas in the acute phase 2

  • DWI: affected areas show increased diffusion signal in the acute phase

Treatment consists of administering 100% oxygen which accelerates the elimination of carboxyhemoglobin 9.

For involvement in and around the globus pallidus, consider:

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1
    Drag here to reorder.
  • Case 2
    Drag here to reorder.
  • Case 3
    Drag here to reorder.
  • Case 4
    Drag here to reorder.
  • Case 5
    Drag here to reorder.
  • Case 6
    Drag here to reorder.
  • Case 7
    Drag here to reorder.
  • Case 7
    Drag here to reorder.
  • Case 8: gas geyser syndrome
    Drag here to reorder.
  • Case 9: with white matter involvement
    Drag here to reorder.
  • Case 10
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.