20th International Congress of the European Association for Endoscopic Surgery (EAES)

Introduction: Laparoscopic surgery is implicated with increased oxidative stress. On the other hand, surgical trauma and manipulation of the intestine during open surgery cause increased inflammatory response and oxidative stress generation. Our study aimed to investigate and compare different oxidative stress markers in patients underwent laparoscopic (LAP) or conventional resection (OP) for colorectal cancer. Materials and Methods: Sixty patients with colorectal cancer were assigned randomly in two groups (LAP and OP) of 30 patients each. The mean end point of the study was to analyzed and compared different oxidative stress markers between the groups. Lipid peroxidation was analyzed by measuring 8-epiPGF2a, protein oxidation by protein carbonyls (CP), damage by nitrogens by 3-nitrotyrosine (3-NT), and RNA damage by 8-OHG. Blood samples were collected preoperatively, 5 min after pneumoperitoneum deflation (LAP), or after the end of GI tract manipulation (OP), 6 h, and 24 h after the operation. Results: Comparison of 8-epiPGF2a between the groups showed significant difference at 6 h (p \ 0.0001), and 24 h postoperatively (p \ 0.03). In OP decreased significantly 24 h postoperatively compared to preoperative values (p \ 0.0001). In LAP showed significant decrease 5 min after pneumoperitoneum deflation (p \ 0.0001), 6 h (p \ 0.0001), and 24 h postoperatively (p \ 0.0001). Comparison of CP between the groups showed no differences. Variations of PC in each group, in each time interval are no significant. Comparison of 3-NT between the groups showed significant difference at 6 h (p = 0.01), and 24 h postoperatively (p = 0.014). In LAP decrease significantly 24 h postoperatively (p = 0.027). Comparison of 8-OHG between the groups showed significant difference 24 h after the operation (p = 0.009). In LAP significantly decrease found 24 h postoperatively (p = 0.016). Conclusion: This study has proved that laparoscopic surgery for colorectal cancer is associated with lower oxidative stress, compared to open surgery, during the early postoperative period. (Registered Clinical Trial no NCT00928928; www.clinicaltrials.gov) O002 Physiology, Pathophysiology, Immunology