Small bowel obstruction and incisional hernia after laparoscopic and open colorectal surgery: a meta-analysis of comparative trials

Introduction: Recent studies show contrasting data on the impact of laparoscopy on long-term complications such as the occurrence of small bowel obstruction (SBO) and incisional hernia (IH). The objective of the study was to assess the impact of the laparoscopic approach on the occurrence of SBO and IH after colorectal resection. Methods: Two trained investigators independently searched MEDLINE, Embase, PubMed, and the Cochrane Central Register of clinical trials for studies comparing laparoscopy to open surgery for mid- to long-term outcomes after colorectal surgery. No language restriction was set. Sensitivity analyses for study design and quality, conversion rate, type of procedure (colon or rectal surgery), and length of follow-up were performed. Results: Eleven RCTs and 14 non-RCT comparative studies for a total of 6540 patients were included in the analysis. Laparoscopy was associated with a significant reduction in the occurrence of SBO (RR 0.57, [95 %CI 0.42–0.76], 16 trials) and IH (RR 0.60, [95 %CI 0.50–0.72], 19 trials). Sensitivity analysis including only RCTs confirmed the reduction in SBO (RR 0.58, [95 %CI 0.39–0.87], 8 trials), while the difference was close to significance for IH (RR 0.76, [95 %CI 0.56–1.03], 7 trials). Sensitivity analysis including only studies with conversion rate lower than 15 % showed a significant protective effect of laparoscopy for both SBO (RR 0.53, [95 %CI 0.37–0.77], 11 trials) and IH (RR 0.58, [95 %CI 0.47–0.72], 12 trials). No significant difference between laparoscopy and open surgery was found when the analysis was limited to studies with conversion rate >15 % (SBO: RR 0.60 [0.32–1.12], IH: RR 0.70 [0.46–1.06]). Length of follow-up did not substantially impact on results. Conclusion: Laparoscopic surgery is associated with a significant reduction in both SBO and IH compared to the open approach. A low conversion rate in the laparoscopic group plays a key role for reduction in both SBO and IH.