The OAGB has become increasingly popular in Australasia as it delivers similar weight loss to the traditional Roux-en-y bypass (RYGB), with faster operating times and generally a lower peri-operative morbidity rate. One main difference between the OAGB and the RYGB relates to the longer Bilio-pancreatic (BP) limb. While a 50cm BP limb is common for the RYGB, 150-200 cm length is prevalent in the OAGB especially in the super-obese or patients with significant diabetes.
We present a patient with refractory reflux 2 years after an OAGB for NIDDM on 420 units of insulin a day, and HbA1c of 9.5% and a BMI of 46. Despite a BMI of 28 and a reduction in insulin dose to 36 units per day (HbA1C 6.5%) the patient had persistent bloating and sporadic diarrhoea with faecal incontinence despite endoscopic investigations and medical therapy. She was also PPI dependant despite successful correction of a hiatus hernia at the time of original surgery. We also present the current evidence base of the nature of BP limb lengthening, which leads to progressive deactivation of pancreatic enzymes with longer bypass length and risks of fat malabsorption and carbohydrate intolerance presenting as FODMAPs symptoms.
At laparoscopy the hiatal repair was intact. The BP limp was 200 cm and the common channel 550 cm. The bypass was shortened to give a 30 cm BP limb and 60 cm alimentary limb with successful resolution of her symptoms.
Lengthening the BP limb at the time of gastric bypass may likely create a greater weight loss through a variety of mechanisms. While adaptation of the small bowel will lead to amelioration of initial side effects from surgery in some patients, there will be others where further surgery is required. It is not currently possible to determine who will be most at risk of intolerable side effects from bariatric surgery.