Lactate metabolism during laparoscopic cholecystectomy: comparison between CO2 pneumoperitoneum and abdominal wall...

Recent reports have implicated CO2 pneumoperitoneum for laparoscopic surgery in the occurrence of postoperative mesenteric ischemia. With this kind of surgery, the increase in blood lactate levels has been attributed to anaerobic metabolism, probably due to tissue ischemia induced by high intraabdominal pressure (IAP). The aim of this study was to evaluate the metabolic repercussion of CO2 pneumoperitoneum during laparoscopic cholecystectomy (LC). This was a prospective randomized study of CO2 pneumoperitoneum (PP group, n = 19) versus abdominal wall retraction (AWR group, n = 15). Demographic data were collected preoperatively. Four-trocar LC was performed with either a CO2 pneumoperitoneum (IAP of 12 mmHg) or abdominal wall retraction (abdominal wall pressure 6-10 kp). Intraoperative and postoperative blood samples were collected and lactate levels determined by enzymatic analysis. Repeated measures analysis of variance (MANOVA) was used for statistical analysis. Significance was evaluated at p < 0.05. The groups were shown to be homogeneous. Lactate concentration, expressed as mean (SD), went from 25.4 (14.4) mg/dl at baseline to 18.9 (13.6) mg/dl 4 hours after surgery in the PP group and from 19.4 (6.1) mg/dl at baseline to 17.8 (14.7) mg/dl in the AWR group. No significant differences were found between groups intraoperatively (p = 0.116) or postoperatively (p = 0.99). Our study did not show significant differences in blood lactate levels during LC with CO2 pneumoperitoneum compared to the same procedure with abdominal wall retraction.