A prospective comparative study of arterial blood gas parameters in smoker versus non-smoker patients undergoing laparoscopic cholecystectomy

Background and Aims: Smoking is a risk factor for postoperative pulmonary complications in patients undergoing general anaesthesia. These may get amplified with effects of pneumo-peritoneum and carbon dioxide (CO2) insufflation during laparoscopic surgeries. Our aim was to compare metabolic and blood gas analysis of smokers versus non-smoker patients during laparoscopic surgeries under general anaesthesia. Methods: After permission from institutional review board, 60 patients undergoing laparoscopic cholecystectomy were divided into two groups, smokers and non-smokers (30 each). Along with baseline haemo-dynamic parameters, arterial blood gas sampling was done to assess and compare PCO2, pH and bicarbonate (HCO3) values at various time intervals with respect to pneumo-peritoneum creation, between smokers and non smokers. Results: Baseline systolic blood pressure was higher and oxygen saturation was significantly lower in smoker group. PCO2and end-tidal CO2were significantly higher in smokers at all intervals (P < 0.001). pH was significantly lower and HCO3higher, in smokers after creation of pneumo-peritoneum. Increase in PCO2 due to pneumo-peritoneum was higher in the smoker group (3.49 +/- 8.5) mmHg versus non smoker (0.56 +/- 4.86) mmHg, although statistically not significant. Change in pH and HCO3was similar between smokers and non-smokers. Conclusion: There is a significant difference in baseline arterial blood gas characteristics between smokers and non-smokers. Metabolic effects of CO2insufflation and increased intraabdominal pressure appears to be more enhanced in smokers.