Carboxyhaemoglobin, blood gas

Diagnostic Use

Haemoglobin bound to carbon monoxide is known as carboxyhaemoglobin. Carbon monoxide has a higher affinity for haemoglobin than oxygen and thus high concentrations of carbon monoxide prevent O2 from binding to haemoglobin, reducing oxygen delivery to the tissues.

Carbon monoxide poisoning may be intentional or accidental (e.g. smoke inhalation from a house fire, exposure to vehicle exhaust fumes, household exposure from malfunctioning gas boiler etc.). Symptoms of carbon monoxide poisoning range from headache and fatigue in mild cases to hypoxia and decreased level of consciousness in severe cases.

Carboxyhaemoglobin can be measured by a co-oximetry module which is available on most blood gas analysers.


Core Biochemistry

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Carbon Monoxide, blood gas
COHb, blood gas
FCOHb, blood gas

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