Anastomotic fistula after emergency enterectomy for retrograde intussusception after gastric bypass

Background

Small bowel intussusception is more commonly seen in children.1 2 In adult life, it is usually associated with pre-existent small bowel pathology like polyps, lipoma or neoplasms. In obesity surgery, mainly after gastric bypass, intussusception is a rare condition that might cause either recurrent mild symptoms that pose a diagnostic problem or an urgent condition requiring emergency surgery.3–6 When small bowel resection is mandatory it might prove a challenge to avoid short bowel syndrome without compromising future weight gain and consequent recurrent obesity.

Case presentation

A 36-year-old female patient with a history of a laparoscopic Roux-en-Y gastric bypass 3 years earlier was admitted to the emergency room with severe abdominal pain. Prior metabolic comorbidities were: sleep apnoea, dyslipidaemia, arterial hypertension and steatosis. Currently experiencing no comorbidities with regular follow-up and normal blood tests under supplementation with folic acid and iron.

The patient weight before surgery was 106 kg with a body mass index of 44,69 kg/m². Follow-up evaluation revealed a weight of 64.3 kg and 61 kg, respectively, 1 and 3 years after surgery. Percentage of EWL (Excess weight loss) at 1 year was 89.3% and at 3 years was 95.3%, respectively.

Investigations

Emergency room patient examination revealed a distended and tender abdomen and blood tests showed 12.2 x10⁹/L leucocytosis with neutrophilia. An abdominal CT scan was performed showing a Roux-limb retrograde intussusception with pneumatosis and reduced bowel wall enhancement (figure 1). An emergent laparotomy was performed through a midline incision. After identifying the intussusception which was located around 20 cm distally to the jejunojejunal anastomosis, it was manually reduced revealing an intestinal perforation of the hidden segment (figure 2). Around 30 cm of small bowel was resected and a side-to-side stapled anastomosis was performed. On the fifth postoperative day, patient status deteriorated, with increasing abdominal pain and laboratorial work-up revealed an elevated C reactive protein of 14 mg/dL and 8.5 x10⁹/L leucocytes. Wound infection was present with enteric fluid drainage. A CT scan revealed pneumoperitoneum and an enterocutaneous fistula (figure 3). These findings prompted a surgical revision. Access to the abdominal cavity was done through the previous midline incision, revealing a small perforation around 4 cm proximally to the recently performed anastomosis and 4 cm distally to the Roux limb emergence (figure 4). All small bowel was then measured to allow for a better decision making. The alimentary limb’s length was 130 cm, the biliopancreatic limb was 60 cm and the common limb was 270 cm.

Treatment

Unable to safely perform a new anastomosis without compromising either of the previous anastomosed segments’ blood supply (original Roux limb anastomosis and intussusception anastomosis) the surgical team decided to resect these two previous anastomosis. After resection, three separate jejunal segments were left (alimentary, biliopancreatic and common limbs) (figure 5). The resected portion measured 30×10 cm taking into account recent follow-up evaluation with no vitamins or iron deficiency and the patient’s haemodinamical stability and circumscribed sepsis, the surgical team’s decision was to perform a double side-to-side manual anastomosis with a two layered 2–0 poliglactin suture. The main decision in performing both anastomosis was to prevent one or several jejunostomies and iterative surgical procedures. However, a very important decision had to be made regarding the placement of both anastomosis. In order to prevent postoperative short bowel syndrome, the biliopancreatic limb was anastomosed 40 cm proximally in the alimentary limb, performing the following anastomosis at the end of this segment. In this way, the final layout of the small bowel was as follows: alimentary limb 80 cm, biliopancreatic limb 50 cm and common limb 290 cm (figure 6).

Outcome and follow-up

On the first postoperative day, the patient ensued an acute respiratory distress syndrome, managed with non-invasive ventilation. Due to this event, the patient was put on intravenous nutrition and oral intake was only resumed on day 8. A superficial wound infection was managed with daily dressings. The patient was discharged home on postoperative day 18. Discharge medication included low-molecular-weight heparin, vitamins and iron supplementation. The patient was evaluated on a follow-up appointment at day 30 after discharge. No further complications were identified and patient’s weight was 58 kg (103% excess weight loss (EWL)). Last recorded weight before this event was 61.5 kg 1 month earlier. All lab tests were normal including haemoglobin, vitamins and ferritin.