Protein deficiency after gastric bypass: The role of common limb length in revision surgery.

BACKGROUND: Bariatric surgery, especially the gastric bypass procedure, is an effective therapy for morbid obesity, but may reduce protein absorption and induce protein deficiency (PD). A recent study reported an issue about common limb length for PD. OBJECTIVE: This study aimed to examine the prevalence of PD after gastric bypass surgery and investigate the role of common limb length in PD-related revision surgery. SETTING: Hospital-based bariatric center. METHODS: From 2001 to 2016, 2397 patients with morbid obesity who underwent bariatric/metabolic surgery with 1-year follow-up were recruited. Serum albumin and total protein were measured before and 1 year after surgery. Medical records of patients who underwent revision surgery due to PD were reviewed. RESULTS: The overall prevalence of PD was .5% preoperatively. The prevalence of PD increased to 2.0% at 1 year after surgery. The incidence was highest in one-anastomosis gastric bypass (2.8%) followed by Roux-en-Y gastric bypass (1.8%). Until the end of follow-up, all 19 patients who underwent revision surgery for intractable PD had a relatively short common limb length of <400 cm. After elongation of the common limb length to >400 cm in revision surgery, PD improved in all patients. CONCLUSIONS: A subset of patients can develop PD after gastric bypass surgery when the common limb length is <400 cm. In patients with intractable PD after gastric bypass surgery, revision surgery for elongation of common limb length to >400 cm is mandatory to avoid PD-related complications.