Comparison of peritoneal oxidative stress during laparoscopy and laparotomy.

STUDY OBJECTIVE: To identify oxidative stress in peritoneum during laparoscopic and open surgery by measuring products of lipid peroxidation, and to determine whether surgical approach influences the type of oxidative metabolite synthesized. DESIGN: Retrospective analysis (Canadian Task Force classification II-2). SETTING: University-affiliated hospital. PATIENTS: Twenty-eight consecutive women with uterine myomas or ovarian cysts. INTERVENTION: Laparoscopic or open surgery (14 patients each). MEASUREMENTS AND MAIN RESULTS: We obtained 1 x 1-cm squares of peritoneum at the beginning and end of surgical procedures away from sites of surgery. 8-Isoprostaglandin F(2alpha), hydroxyeicosatetranoic acids (HETEs), and malondyaldehyde (MDA) were measured by enzyme-immunoassay, high-performance liquid chromatography, and thiobarbituric acid adduction method, respectively. Comparisons showed significant increases in 5-HETE and 8-prostane in the laparoscopy group, which were correlated with duration of pneumoperitoneum and volume of carbon dioxide (CO(2)) insufflated, respectively. In the laparotomy group only MDA rose significantly related to duration of surgery. CONCLUSIONS: Lipid peroxidation was observed in peripheral peritoneum during laparoscopic surgery, mediated through noncyclooxygenase and lipoxygenase pathways, and appears to be due to effects of CO(2) pneumoperitoneum. Biochemical reactions were also observed in the laparotomy group, but are thought to be related to mechanisms other than lipid peroxidation.