The overall risk of bowel resection is low in patients having small bowel obstruction after Roux-en-Y gastric bypass (RYGB) and the risk of ending up with a short bowel is very low, according to a study led by researchers from Linköping University Hospital, Linköping, Sweden.
While RYGB is relatively safe, one of the most serious complications is internal herniation with small bowel obstruction resulting in ischemia and necrosis of the herniated bowel. Symptoms of internal herniation are intermittent abdominal pain, nausea and bloating, although the authors stated that symptoms can be ‘vague’. Closure of the mesenteric openings during RYGB reduces the risk of internal herniation, and since 2016 in Sweden, the standard of care has been to close the mesenteric openings using clips or sutures.
Nevertheless, the authors stated that there have been reports where internal herniation after RYGB has resulted in extensive small bowel obstruction. To assess the incidence of small bowel resection in patients with RYGB, the researchers used data from the Scandinavian Obesity Surgery Registry (SOReg), a nationwide quality registry that included 98% of all bariatric procedures in Sweden.
Between 2007 and 2019, a total of 57,255 patients underwent RYGB, 49,210 (89%) patients attended the one-year follow up and 20,619 (37%) patients attended the five-year follow up. Closure of the mesenteric openings RYGB was performed in 36,229 (78%) patients at primary surgery, data regarding closure of mesenteric defects was available in 81% of patients. In 3,659 (6%) patients, remedial surgery for small bowel obstruction was required over five years of follow-up. In the cohort having surgery for small bowel obstruction, 65.5% of patients had the mesenteric openings closed at primary surgery, compared to 79.0% in the group not having surgery for small bowel obstruction (p<0.001).
A small bowel resection was required in just 188 (0.3%) of patients and there were no differences in baseline characteristics for patients requiring small bowel resection compared to those that did not. The proportion of patients having mesenteric windows closed were similar in the group with and without small bowel resection, 77.4 and 78.3% respectively (p=0.79).
The most common cause of resection was internal herniation (34%), kinking of the jejunojejunostomy (19%), adhesions (18%) and intussusception (7%). In the remaining 22% of cases, the cause of small bowel obstruction was documented as unclear in the registry. Kinking of the jejunojejunostomy was most common in the first six weeks after surgery but was rare at the two- and five-year follow-up. At five years, the most common cause requiring small bowel resection was internal herniation (Figure 1).
“We found that the need for small bowel resection for internal herniation after RYGB to be rare, affecting only 0.3% of patients,” the authors noted. “This is in line with previous studies which have demonstrated small bowel resection in 0.2% of procedures. The low incidence makes studies on the subject challenging.”
The authors recommended that all patients who have RYGB should be made aware of the possible complications and be instructed to go seek medical advice if they develop severe abdominal pain. They stressed that when bowel ischemia is suspected the patient should undergo urgent surgery ‘without delay’.
“Bowel ischaemia should be suspected in patients presenting to the emergency department with disproportional abdominal pain and/or need for high doses of analgesia and poor general condition,” they authors concluded. “Such patients should immediately be taken to the operating theatre.”
The findings were featured in the paper, ‘Very low risk of short bowel after Roux-en-Y gastric bypass – a large nationwide Swedish cohort study’, published in SOARD. To access this paper, please click here