[Analysis of basic activity of electroencephalogram in patients with carbon monoxide intoxication for monitoring efficacy of treatment].

Electroencephalography (EEG) should be used in carbon monoxide intoxication on the basis of its clinical significance. The aim of this study was to analyze basic activity of EEG in acute carbon monoxide intoxication and clarify its significance for monitoring the efficacy of treatment. Thirty-six cases with acute carbon monoxide intoxication were treated with either hyperbaric or normobaric oxygenation. EEG was performed every 2 weeks for a total of three times in each case. Basic activity in the first EEG revealed slow waves (slow alpha, theta or delta) and normal waves (9-11 Hz) in 11, and 25 cases, respectively. When changes of the basic activity of EEG were analyzed, they were classified into 3 patterns: pattern A (faster over 2 Hz), B (stable) and C (slower over 2 Hz) in 7, 27 and 2 cases, respectively. Three cases with the pattern B turned to be an intermittent type of carbon monoxide intoxication. Two cases of pattern C were related with poor prognosis and death. In conclusion, the patterns in the basic activity change of EEG at the interval of 2 weeks in acute carbon monoxide intoxication are useful in monitoring efficacy of treatment.