Case of the Month #34 Carbon Monoxide Poisoning

Published 01/12/2022

What are the clinical features of Carbon Monoxide poisoning?

There can be variable presentation of CO poisoning, which can be non-specific and mild. The clinical presentation depends on factors include the duration and severity of exposure, and may include: 

  1. Headache 

  1. Dizziness  

  1. Nausea  

  1. Changes to mental status; confusion, loss of consciousness, coma  

  1. Tachycardia  

  1. Hypotension  

  1. Cherry red nail beds and mucous membranes (only seen post-mortem) 

  1. Retinal haemorrhages  

  1. Papilloedema  


Laboratory results may include: 

  1. Elevated Carboxyhaemoglobin (COHb)  

  1. Oxygen saturation gap - difference in readings between saturation probe and arterial blood gas  

  1. Increased serum lactate 

  1. Abnormal renal function  

  1. Abnormal liver function  

  1. Elevated Creatinine Kinase 

  1. Elevated Troponin-I  

  1. Derangement of coagulation