RESUMEN
BACKGROUND: The comparative evidence regarding the outcomes of closure versus non-closure of mesenteric defects in laparoscopic Roux-en-Y gastric bypass (LRYGB) is poorly understood. We aimed to compare the outcomes of closure versus non-closure of mesenteric defects in LRYGB for morbid obesity. METHODS: We conducted a search of electronic information sources to identify all comparative studies investigating the outcomes of closure versus non-closure of mesenteric defects in patients undergoing LRYGB for morbid obesity. We used the Cochrane risk of bias tool and the ROBINS-I tool to assess the risk of bias of RCTs and observational studies, respectively. Random or fixed effects modelling was applied as appropriate. RESULTS: We included 10,031 patients from six observational studies and 2609 patients from two RCTs. Analysis of observational studies showed closure defects resulted in lower risks of internal hernia (OR 0.28, 95% CI 0.15, 0.54) and reoperation for small bowel obstruction (SBO) (OR 0.30, 95% CI 0.10, 0.83); no difference was found between the two groups in terms of SBO not related to internal hernia (OR 1.19, 95% CI 0.47, 2.99), early SBO (OR 0.74, 95% CI 0.04, 14.38), anastomotic leak (OR 0.84, 95% CI 0.45, 1.57), bleeding (OR 1.08, 95% CI 0.62, 1.89), and anastomotic ulcer (OR 2.08, 95% CI 0.62, 6.94). Analysis of RCTs showed closure of defects resulted in lower risks of internal hernia (OR 0.29, 95% CI 0.19,0.45) and reoperation for SBO (OR 0.51, 95% CI 0.38, 0.69) but higher risks of SBO not related to internal hernia (OR 1.90, 95% CI 1.09, 3.34) and early SBO (OR 2.63, 95% CI 1.16, 5.96); no difference was found between the two groups in terms of anastomotic leak (OR 1.95, 95% CI 0.80, 4.72), bleeding (OR 0.67, 95% CI 0.38, 1.17), and anastomotic ulcer (OR 2.08, 95% CI 0.62, 6.94). CONCLUSIONS: Our results suggest that closure of mesenteric defects in LRYGB may be associated with lower risks of internal herniation and reoperation for SBO compared with non-closure of the defects (moderate certainty). The available evidence is inconclusive regarding the risks of SBO not related to internal hernia and early SBO (low certainty). More RCTs are needed to improve the robustness of the available evidence.