THE SEVERE winters of 1976 to 1977 and 1977 to 1978 and the current energy crisis have led to improved home insulation and the increased use of space heaters. This has substantially increased the potential for accidental carbon monoxide (CO) poisonings in the home. The use of internal combustional engines in any relatively closed environment can also cause CO poisoning. Since the symptoms of CO poisoning are nonspecific, many conditions will escape early diagnosis unless physicians consider this diagnostic possibility in patients with headache, nausea or vomiting, or confusional state.
Our first understanding of the pathophysiology of CO dates from the work of Claude Bernard in 1857, when he ascribed the toxic effects to tissue hypoxia. In 1895, Haldane1 described the underlying mechanism for CO toxicity when he demonstrated that CO reversibly interacted with hemoglobin, blocking the binding of oxygen to hemoglobin, thus causing tissue hypoxia. He also demonstrated