Study of the effect of exposure to carbon monoxide on cardiovascular system

ABSTRACT

A study was conducted to find the CVS effects of CO exposure especially changes in BP, ECG changes especially ischemic changes and findings suggesting peripheral vascular diseases. Data were collected from all workers exposed to CO gas in a Sand Brick Factory [25 workers]. A control group [25 workers] was also randomly selected from other departments in the same plant, of the same sex [male], of the same socioeconomic conditions and they had never been exposed to CO during their working life. All workers were interviewed using a specially designed questionnaire and a CVS questionnaire of London School of Hygiene. Workers were clinically examined and an ECG was recorded for each one. If no signs of ischemia were detected, the ECG was repeated after a standardized effort test using a bicycle ergometry [subjective maximal exercise test]. Results obtained in this study revealed that there was no difference between exposed and controls as regard palpitation and pain denoting intermittent claudication. In addition there were no changes in BP as a result of exposure CO among the exposed group. However, exposure to CO resulted in increase of prevalence of ischemic heart changes among the studied workers especially older age group [above 40 years of age]. This high prevalence of ischemic changes among older exposed workers could be explained by the cumulative synergistic effect of CO exposure and smoking as all of them were smokers. As regard ECG criteria other than ischemia, it was noted that exposure to CO resulted in sinus bradycardia which was significantly more met among exposed group than their controls