Effects of omega-loop bypass on esophagogastric junction function

Area of Science:

• Bariatric Surgery
• Gastroenterology
• Esophageal Physiology

Background:

• Limited objective data exists on omega-loop gastric bypass (OGB) effects on the gastroesophageal junction and reflux.
• Understanding these effects is crucial for patient management and surgical technique refinement.

Purpose of the Study:

• To evaluate the impact of OGB on esophageal motor function.
• To assess the potential for increased gastroesophageal reflux following OGB.
• To compare OGB outcomes with sleeve gastrectomy (SG) regarding reflux and esophageal function.

Main Methods:

• Prospective study involving clinical assessment, endoscopy, high-resolution impedance manometry (HRiM), and 24-hour pH-impedance monitoring (MII-pH) before and 1 year after OGB.
• A control group of obese patients who underwent sleeve gastrectomy (SG) was included for comparison.
• Objective measurements of intragastric pressure (IGP) and gastroesophageal pressure gradient (GEPG) were analyzed.

Main Results:

• OGB patients reported no de novo heartburn or regurgitation; endoscopy revealed no esophagitis or biliary issues.
• Manometric features remained stable post-OGB, while IGP and GEPG significantly decreased (P<.01).
• OGB led to a dramatic reduction in reflux events (median 41 to 7; P<.01), contrasting with SG, which increased reflux and esophageal acid exposure (P<.01).

Conclusions:

• OGB preserves gastroesophageal junction function and does not increase gastroesophageal reflux.
• The beneficial effect of OGB is attributed to the reduction in intragastric pressure and gastroesophageal pressure gradient.
• OGB demonstrates a favorable safety profile regarding esophageal function compared to SG.