Mesenteric defect closure in LRYGB associated with a lower rate of internal herniation


Closure of the mesenteric defects with clips during laparoscopic Roux-en-Y gastric bypass (LRYGB) reduces the rate of internal herniation compared with non-closure, according to the outcomes from a single-centre randomised controlled trial by researchers from Zealand University Hospital, Koege, Denmark. However, the investigators noted that postoperative complications were more frequent after closure of the defects, mostly owing to torsion of small bowel at the jejunojejunostomy. The findings were featured in the study, ‘Randomized clinical trial on closure versus non-closure of mesenteric defects during laparoscopic gastric bypass surgery’, published in the BJS.

The authors noted that an antecolic, antegastric LRYGB creates a mesenteric defect between the mesentery of the alimentary limb and the mesocolon (Petersen’s space), and between the biliopancreatic limb and the common limb at the enteroenteroanastomosis (mesojejunal defect). The reported incidence of (intermittent) internal herniation in patients without closure of the mesenteric defects is 4–17%. However, whether to close these defects with a suture or clip has not been studied as part of a RCT. Therefore, the researchers sought to evaluate the benefit/harm of closing the mesenteric defects with clips during LRYGB.

The investigators looked at enrolling 422 patients in the trial but owing to changes in the Danish eligibility criteria for bariatric surgery were changed and another RCT reported that the benefits from closing the mesenteric defects with sutures were much greater than expected. As a result, the authors “found it unethical to continue”, and decided to end patient inclusion before reaching the calculated sample size (1 June 2017). In total, 401 patients were included in the study.

Outcomes

In total, 201 patients were randomised to closure and 200 to non-closure of the mesenteric defects and at 24 months 398 (99.3 per cent) had follow-up respectively, and 127 of 401 patients (31.7 per cent) were included in the five-year follow-up.

Sixteen of 200 included patients had surgery for internal herniation in the non-closure group (seven patients had an internal hernia at Petersen’s space, four at the mesojejunal defect and five at both Petersen’s space and the mesojejunal defect) and nine of 201 in the closure group (five hernias were located at Petersen’s space, three at the mesojejunal defect and one at both Petersen’s space and the mesojejunal defect), within two years. The cumulated risk of internal herniation in the non-closure was 8% vs 4.4% in the closures group after two years (p=0.231).

After five years, 31 patients in the non-closure group had internal herniation (13 hernia were located at Petersen’s space, seven at the mesojejunal defect, and 11 at both Petersen’s space and the mesojejunal defect) and 13 (of 92 patients) had internal herniation (five were located at Petersen’s space, five at the mesojejunal defect and three at both Petersen’s space and the mesojejunal defect). The cumulated risk of internal herniation in the non-closure was 15.5% and 6.5% per cent in the closures group after five years (p=0.005).

Six (of 200) patients in the non-closure group had intermittent internal herniation and nine (of 201) in the closure group, at two years. The cumulated risk of intermittent internal herniation in the non-closure and closure groups after two years was 3% and 4.5% (p=0.436), respectively.

After five years of follow-up, 13 (of 104) patients in the non-closure group were diagnosed with intermittent internal herniation vs 10 (of 92) in the closure group with the authors reporting a cumulated risk of intermittent internal herniation in the non-closure and closure groups of 6.5% and 5%, respectively (p=0.535).

Ten patients in the closure group and five in the non-closure group had severe complications (Clavien–Dindo grades IIIb–V), although this difference was not statistically significant. No patients died within 30 days.

“This RCT showed that closure of the mesenteric defects with clips during LRYGB reduces the rate of internal herniation compared with non-closure. There was no difference in the incidence of intermittent internal herniation between the two groups,” the authors noted. “Postoperative complications were more frequent after closure of the defects, mostly owing to torsion of small bowel at the jejunojejunostomy. Closure of the mesenteric defects was associated with a clinically non-relevant prolonged operating time and lower haemoglobin level on the first postoperative day.”

Further information

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