Laparoscopic Reversal of One-Anastomosis Gastric Bypass After Sleeve Gastrectomy: A Case Report

Introduction

Bariatric and metabolic surgery (BMS) is the most effective therapy for patients with morbid obesity and type 2 diabetes mellitus (T2DM). Due to the increasing global prevalence of obesity, the number of BMS procedures has rapidly increased worldwide, but the types of operation are still in development. Today, these surgical interventions are still associated with a risk of perioperative complications [1].

One-anastomosis gastric bypass (OAGB) is a variant of gastric bypass that involves creation of a long gastric pouch and a single gastrojejunal anastomosis. It has gained acceptance as an effective BMS procedure. According to the International Federation of Surgery for Obesity (IFSO), OAGB accounted for 4.7% of total bariatric procedures worldwide in 2017 [2].

Laparoscopic sleeve gastroplasty (LSG) is a procedure in which the greater curvature is resected, reducing the volume of the stomach by about 80%, which leads to significant limitation of food intake. Additionally, removal of the gastric fundus may reduce circulating ghrelin levels, and this contributes to appetite regulation [3].

Nutritional deficiency is a condition that occurs as a late complication after LSG. In a study done by Gehrer et al, the percentages of patients experiencing deficiencies of vitamins and minerals were reported as follows: zinc (34%), vitamin D3 (32%), iron (18%), vitamin B12 (18%), and folic acid (22%). However, compared with laparoscopic Roux-en-Y gastric bypass, the frequency of nutrient deficiencies was generally lower after LSG [4]. The most common complications after LSG are leakage, bleeding in the staple line, gastric pouch stenosis, wound infection, nutrient deficiencies, gastroesophageal reflux disease, and weight regain. Less frequently, acute pancreatitis, partial spleen infarction, and pulmonary embolism are encountered [5,6].

Although OAGB is very common and generally successful, there is a small subset of patients who can develop severe late complications like refractory protein-calorie malnutrition, chronic diarrhea/vomiting, micronutrient deficiencies, and progressive hepatic failure. In these extreme cases, reversal to near-normal anatomy may be needed as a salvage procedure. However, reversal is very rarely documented, and it becomes even more unlikely and difficult in patients who have already undergone sleeve gastrectomy due to the decreased gastric reservoir, vascular changes, and adhesions from previous surgery [7,8]. Documentation of such cases is important as it helps in making decisions in high-risk bariatric patients, can provide early warning signs for urgent escalation, and aids in developing algorithms for nutritional follow-up and surgical intervention.

Case Report

A 28-year-old female patient was referred to the gastroenterology clinic in April 2023 for progressive weakness and suspected metabolic myopathy. The patient had undergone a laparoscopic sleeve gastrectomy procedure at 15 years of age. The patient’s weight before undergoing a sleeve gastrectomy procedure was 98 kg, with a body-mass index (BMI) of 37. The patient’s lowest weight after undergoing a sleeve gastrectomy procedure was 70 kg, with a BMI of 27, recorded 3 years post-surgery. The patient then gained weight to 83 kg, recorded 5 years post-surgery, and underwent an OAGB procedure in June 2023. At the time of referral to the gastroenterology clinic, the patient’s weight was recorded as 55 kg, with a BMI of 21. Three months after OAGB, she underwent laparoscopic cholecystectomy.

Following her OAGB, there had been a lack of follow-up. There was also a lack of compliance with protein supplements and vitamins. She also started to develop gastrointestinal symptoms, including reduced oral intake, watery diarrhea, nausea, and vomiting. She also became unable to walk or stand for more than a few minutes due to weakness and numbness of her lower limbs bilaterally. Her thiamine level (vitamin B1) was unknown. However, empirical treatment of thiamine was given. She also stopped taking antidepressants due to intolerance. She also stopped taking vitamin B12 due to high levels of the same. She appeared pale and cachectic but did not present with other symptoms.

Examinations revealed mild pallor, low BMI, hepatocellular jaundice, and diffuse abdominal tenderness without signs of an acute abdomen. Laboratory evaluation of the patient showed hypoalbuminemia of 2.6 g/dL, elevated bilirubin of 26/15 mg/dL, mildly elevated prothrombin time of 1.28, and aspartate aminotransferase/alanine aminotransferase (AST/ALT) of more than twice the upper limit. Esophagogastroduodenoscopy revealed a nonperforated marginal ulcer and a suspected abnormal fistulous communication; however, the term ‘gastro-gastric fistula’ was avoided because the patient had a prior sleeve gastrectomy (Figure 1). Confirmation of the above findings was similarly obtained from abdominal computed tomography (CT). She was thus admitted for resuscitation, correction of electrolytes, intravenous fluids, and the initiation of a high-protein diet.

Her condition worsened in the next 2 days, and her vomiting and diarrhea increased. There was severe acute hepatocellular damage, indicated by very high levels of aminotransferases. There was also synthetic dysfunction, indicated by coagulopathy. Her international normalized ratio (INR) was 6.7. There was no evidence of viral hepatitis or structural liver disease. There was severe clinical deterioration and unstable metabolism. Therefore, she was classified as a high-risk patient due to acute liver failure. Autoimmune hepatitis was excluded based on negative autoimmune serologies such as antinuclear antibody (ANA), anti-smooth muscle antibody (ASMA), and anti-liver kidney microsomal (LKM) antibodies. There were no clinical features for autoimmune hepatitis. Wilson disease was considered and excluded based on negative biochemical test results, which included ceruloplasmin and 24-hour urine copper, as well as negative genetic tests for Wilson disease (normal ATP7B gene). Hemochromatosis was excluded based on iron studies (Table 1).

In addition, a nasojejunal tube was placed for optimal enteral nutrition support. Despite jejunal tube feeding, high-protein supplementation, and correction of electrolyte abnormalities, the patient continued to have severe intolerance of oral intake with associated vomiting and diarrhea, refractory micronutrient deficiencies, functional decline, and metabolic instability. In view of the severity of malnutrition and liver dysfunction, and failure to show adequate improvement with conservative management, a multidisciplinary team including gastroenterologists, bariatric surgeons, nutritionists, anesthesiologists, and intensivists recommended a laparoscopic reversal of her OAGB procedure as a rescue measure. She was referred for surgery in a state of severe malnutrition, cachexia, and liver dysfunction with suspected pulmonary embolism managed with enoxaparin. In summary, as a result of her condition, nutritional and medical optimization were performed. However, due to her intolerance of jejunal feeding and her general condition, a decision to undergo laparoscopic reversal was made.

The laparoscopic reversal procedure was performed in a stepwise manner. After gaining access to the abdominal cavity, extensive adhesiolysis was carried out to carefully free the gastric pouch, gastrojejunostomy, and surrounding structures from dense adhesions related to previous surgeries. Particular attention was paid to identifying anatomical landmarks and preserving vascular supply (Figure 1). The gastrojejunostomy was then clearly identified and divided using a 60-mm linear stapler (Medtronic Endo GIA™, purple cartridge), thereby disconnecting the bypassed jejunal limb. The length of the biliopancreatic limb was measured at 215 cm, and the common channel was 380 cm. Bowel continuity and perfusion were carefully assessed and preserved.

Restoration of gastric continuity was achieved by creating a latero-lateral gastro-gastric anastomosis between the gastric pouch and the remnant stomach using a 60-mm linear stapler (tan cartridge). The common enterotomy was closed with a running 2-0 absorbable suture and reinforced with interrupted seromuscular sutures to ensure secure closure. A leak test was performed intraoperatively to confirm the integrity of the anastomosis. Hemostasis was secured, and a drain was placed near the anastomotic site. The procedure was completed without intraoperative complications.

Her postoperative course was complicated. She developed septic shock on the second day postoperatively, requiring intensive care unit (ICU) admission, vasopressors, and mechanical ventilation (Clavien-Dindo grade IV). Imaging studies were negative for large bowel leak and pulmonary embolism. Blood cultures were positive for Klebsiella pneumoniae, prompting the initiation of broad-spectrum antibiotics. She developed subdural hematoma with anemia and thrombocytopenia on the fourth day postoperatively, requiring multiple blood product transfusions. She required tracheostomy for her prolonged respiratory failure (Clavien-Dindo grade IIIb). She was given total parenteral nutrition until she tolerated enteral nutrition. With continued critical care from various disciplines, she gradually improved in neurological and hematological status and achieved a Glasgow Coma Scale score of 15/15. Episodes of fever and varying output from the drainage catheter were managed with antibiotics. The patient gradually improved, with mechanical ventilation and oral nutrition. The numbness in lower limbs, insomnia, and pressure sores at the sacrum continued and required management. The patient was discharged home on enoxaparin and oral antibiotics. Follow-up appointments were arranged in neurology, infectious disease, and bariatric surgery clinics.

Following more than 8 months of follow-up, the patient showed signs of gradual improvement in nutritional parameters and liver function tests (Table 1). Long-term follow-up was planned with the bariatric surgery, gastroenterology/hepatology, neurology, and clinical nutrition departments, with regular follow-up of weight, albumin, micronutrient levels, liver function tests, and functional recovery.

Discussion

This case is unusual because OAGB reversal was performed in a patient with a previous sleeve gastrectomy. Unlike most reported OAGB reversals, restoration of anatomy in this setting is technically more complex due to altered gastric anatomy, limited gastric reservoir, and adhesions from prior surgery. The patient’s course was complicated by significant metabolic and nutritional deteriorations that necessitated a complete reversal of the OAGB to a nearly normal anatomy, confirming the need for early recognition and decision-making in such complex post-bariatric patients. Although reversal of an OAGB is not common, it has been reported to be possible in a small series of patients, to manage severe late complications of OAGB [9–11].

In our case, the OAGB was performed because the patient had not lost sufficient weight and had regained weight after the sleeve gastrectomy, which is an accepted indication for the procedure. Following the OAGB, the patient had persistent vomiting and chronic watery diarrhea, leading to a reduction in oral intake, protein-calorie malnutrition, and micronutrient deficiencies. These metabolic complications were accompanied by increasing weakness and signs of neuropathy, which are known complications of severe nutritional deficiencies [12]. Additionally, the patient had severe hepatic dysfunction with extremely elevated levels of transaminases and coagulopathy, which is a life-threatening condition [13]. Nevo et al described severe ketoacidosis of starvation on postoperative day 2 following OAGB in a patient with type 2 diabetes, which was managed in the ICU with glucose and insulin, illustrating the rapidity with which instability can develop [14]. Although other causes of acute hepatitis were ruled out, severe malnutrition and metabolic stress following bariatric surgery can cause significant hepatic impairment [15].

The condition of our patient failed to improve appropriately despite aggressive medical management and nutritional optimization. This condition of the patient prompted the decision for OAGB reversal as a potentially life-saving procedure. This procedure can provide a nearly normal anatomy for the gut. Revisional surgery for OAGB has been performed for various indications. These indications include bile reflux, marginal ulcers, insufficient weight loss/weight regain, and protein-calorie malnutrition [9–11]. The decision for OAGB reversal in this particular case was made in consideration of the severity of malnutrition and liver dysfunction.

The decision to proceed with reversal was based on progressive clinical and metabolic deterioration, including severe protein-calorie malnutrition, worsening liver dysfunction, refractory micronutrient deficiencies, and intolerance to enteral feeding despite intensive nutritional support. Given the failure of conservative management and the life-threatening nature of her condition, reversal was considered a necessary rescue intervention within a multidisciplinary team setting.

Reversal of OAGB in a patient with a previous sleeve gastrectomy is technically challenging due to altered anatomy, dense adhesions from multiple prior surgeries, and a limited gastric reservoir. These factors increase operative complexity and require meticulous adhesiolysis, careful preservation of bowel length and vascular supply, and precise reconstruction to re-establish gastric continuity [16].

True restoration of normal gastric anatomy is not achievable in patients with prior sleeve gastrectomy due to resection of the greater curvature and a permanently reduced gastric reservoir. Despite this limitation, our patient demonstrated gradual clinical and nutritional improvement over 8 months, indicating that restoration of gastrointestinal continuity, even without full recovery of gastric volume, can effectively reverse severe malabsorptive complications.

Although the anatomical correction was successful via the laparoscopic approach, the postoperative course was marked by complications from septic shock and multi-organ failure, which required ICU management. This case illustrates the point that the patient who requires reversal of the condition due to severe malnutrition is an extremely high-risk patient, and the occurrence of complications can take place despite successful anatomical correction of the surgical procedure. At the same time, the patient’s progress to full recovery from the complications can be seen as an illustration that the outcome of complex bariatric complications is not just determined by the surgical procedure but also by the postoperative management of the case [17].

This case highlights the need for early detection of nutritional deficiency, postoperative follow-up, and prompt intervention in patients undergoing revisional bariatric surgery. Specifically, patients with symptoms of vomiting, diarrhea, hypoalbuminemia, and neurological symptoms should be urgently assessed and optimized to avoid progression of their disease and development of severe and life-threatening complications. Moreover, psychosocial factors can affect patient compliance with supplementation and dietary advice, and thus should be included in postoperative follow-up. Similar manifestations have been noted in the literature, including patients with severe weakness, peripheral neuropathy, hypoproteinemia, and liver dysfunction in patients undergoing OAGB. In these patients, reversal of anatomy was noted to improve their symptoms [9–11]. Reversal of OAGB should be reserved for patients with severe and intractable complications and should be undertaken in a multidisciplinary setting.

There are limitations in this report. The information provided is on 1 patient only, and thus it cannot be generalized. Further, information on the length of the limbs in the primary OAGB and micronutrient levels was not fully available. The alternative options that could have been used include prolonged enteral nutrition via a tube in the jejunal position and nutritional optimization before major surgical intervention. However, in this patient, intolerance to nasojejunal feeding, malnutrition, and liver disease despite conservative management supported reversal as a rescue therapy. Further research is necessary in this area regarding the timing and indication of OAGB reversal in such high-risk patients.

Reversal of OAGB can be a life-saving procedure in patients who experience severe malnutrition, micronutrient deficiencies, loss of function, and progressive liver dysfunction following revisional bariatric surgery. It is important for the treating physician to be aware of the early warning signs (vomiting, diarrhea, hypoalbuminemia, neuropathy, liver injury) and to refer the patient to a multidisciplinary team for early intensification of nutritional support, with reversal being considered if there is failure of conservative management. Further studies are required to define the criteria for reversal.

Conclusions

This case report presents a unique and serious complication of revisional OAGB surgery after a previous sleeve gastrectomy, which led to severe protein-calorie malnutrition, resistant micronutrient deficiencies, neurological damage, and severe acute hepatocellular injury with coagulopathy. As intensive medical and nutritional care did not help to stabilize the patient, a laparoscopic reversal to near-normal anatomy was undertaken, despite the inherent limitation of reduced gastric volume following prior sleeve gastrectomy. Although the postoperative course was complicated by septic shock and multiple-organ failure, the patient slowly improved with comprehensive care. This case report underlines the significance of postoperative follow-up care, early detection of nutritional failure, and timely comprehensive care in high-risk bariatric patients.