Does the Length of the Common Channel as Part of the Total Alimentary Tract Matter? One Year Results from the Multicenter Dutch Common Channel Trial (DUCATI) Comparing Standard Versus Distal Roux-en-Y Gastric Bypass with Similar Biliopancreatic Bowel Limb Lengths

Purpose: Although the laparoscopic Roux-en-Y Gastric Bypass (LRYGB) is the gold-standard bariatric procedure, it remains uncertain what the optimal bowel limb lengths are to accomplish maximal weight loss while minimizing nutritional deficiencies and related gastro-intestinal complaints. The aim of this randomized controlled multicenter trial is to investigate the effect of significant lengthening of the length of the Roux limb (RL) at the cost of the length of the common channel (CC) while keeping the biliopancreatic limb (BPL) lengths the same on both study arms. Methods: Four hundred forty-four patients were randomized to receive either a Very Long Roux Limb LRYGB (VLRL-LRYGB) (variable RL length, BPL 60 cm, and CC 100 cm) or a Standard LRYGB (S-LRYGB) (RL 150 cm, BPL 60 cm, and a variable CC length). Results at 1-year follow-up for weight loss, effect on obesity-related comorbid conditions, complications, re-operation rate, malnutrition rate, and re-admission rate were investigated. Results: Weight loss at 1-year showed no significant differences for %EWL (84.3% versus 85.3%, p = 0.72) and %TWL (34.2% versus 33.6%, p = 0.359) comparing VLRL-LRYGB versus S-LRYGB. Malabsorption requiring surgical bowel length adjustment was observed in 1.4% in VLRL-LRYGB group versus 0.9% in S-LRYGB group (p = 0.316). Conclusion: Significant lengthening of the RL at the cost of the common channel seems to have no effect on the weight loss at 1-year follow-up, which supports the theory that absorption of nutrients also occurs in the RL. Nevertheless, long-term results of the VLRL-LRYGB have to be awaited to draw final conclusions as part of the discussion towards optimal limb length in LRYGB surgery.