Determine the extent of carbon monoxide poisoning, toxicity; check on the effect of smoking on the patient; work up headache, irritability, nausea, vomiting, vertigo, dyspnea, collapse, coma, convulsions; work up persons exposed to fires and smoke inhalation.
Carbon monoxide levels are of limited value in testing for smoking, since it is cleared rapidly. The half-life of carboxyhemoglobin in individuals with normal cardiopulmonary function is one to two hours. Urinary cotinine, if available, is preferable as a test for tobacco use. Arterial blood gases may be of limited value in treatment decisions for carbon monoxide poisoning.
Carboxyhemoglobin is useful in judging the extent of carbon monoxide toxicity and in considering the effect of smoking on the patient. A direct correlation has been claimed between CO level and symptoms of atherosclerotic diseases, intermittent claudication, angina, and myocardial infarction. Exposure may occur not only from smoking but also from garage exposure, and from various motors.
References:
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Fechner GG, Gee DJ. Study on the effects of heat on blood and on the postmortem estimation of carboxyhemoglobin and methaemoglobin. Forensic Sci Int. 1989 Jan; 40(1):63-67. PubMed 2925132
Heckerling PS, Leikin JB, Maturen A, Terzian CG, Segarra DP. Screening hospital admissions from the emergency department for occult carbon monoxide poisoning. Am J Emerg Med. 1990 Jul; 8(4):301-304. PubMed 2094235
Krantz T, Thisted B, Strøm J, Sørensen MB. Acute carbon monoxide poisoning. Acta Anaesthesiol Scand. 1988 May; 32(4):278-282. PubMed 3394478
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Carbon Monoxide
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