Predicting Factors in Prognosis of Actue Carbon Monoxide Intoxication

ABSTRACT

Many studies have been reported on predicting factors in prognosis of acute carbon monoxide (CO) intoxication, which are different to the reports. These different results might be caused partially by the variable clinical courses in acute CO intoxication. This retrospective study was designed to investigate the predicting factors of each clinical course in acute CO intoxication. For this study, we evaluated retrospectively 103 admitted patients with acute CO intoxication. Among them, 11 patients (11%) remained as prolonged coma, 21 patients (20%) had developed delayed sequalae, and 71 patients (69%) lived without neurologic deficit. This study evaluated and analyzed predicting factors and its relative risk in prognosis at each course of acute CO intoxication with well-known possible factors. The results were as follows 1. The mental status of patient on admission was related to the concentration of blood CO. 2. The recovery of the mental state after 24 hours of admission was dependent on the exposure time of CO intoxication, the mental status on admission, blood pressure, fractional arterial pressure of CO2. 3. Prolonged coma had close correlation with the exposure time of CO intoxication, the mental status on admission, fractional arterial pressure of 02 0r CO2- 4. Delayed sequalae after recovery of the mental state were dependent on the mental status on admission, bradycardia, interval of the recovery of mental state (or recovery status of mentality within 24 hours). In conclusion, the prognostic factors of patients with acute CO intoxication may be different according to the clinical course of acute CO intoxication. Recovery of mentality in 24 hours of admission may be related to systemic blood pressure at admission which represents cerebral perfusion indirectly, and prolonged coma seems to be related to hypoxemia or hypercapnia on arterial blood gas study at admission which may contribute the profounding cortical damage. The initial mentality of patient on admission can not predict the delayed sequalae after acute CO inoxication, and more observation of patient for estimating the clinical status and the interval of mental recovery during admission, will be needed.