Effect of sleeve gastrectomy and Roux-en-Y gastric bypass on gastrointestinal physiology

Nele Steenackers; Tim Vanuytsel; Patrick Augustijns; Ellen Deleus; Wies Deckers; Christophe M Deroose; Gwen Falony; Matthias Lannoo; Ann Mertens; Raf Mols; Roman Vangoitsenhoven; Lucas Wauters; Bart Van der Schueren; Christophe Matthys

doi:10.1016/j.ejpb.2022.12.018

Effect of sleeve gastrectomy and Roux-en-Y gastric bypass on gastrointestinal physiology

Eur J Pharm Biopharm. 2023 Feb:183:92-101. doi: 10.1016/j.ejpb.2022.12.018. Epub 2023 Jan 2.

Authors

Affiliations

¹ Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium.
² Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium; Department of Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium.
³ Drug Delivery and Disposition, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium.
⁴ Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium; Department of Abdominal Surgery, University Hospitals Leuven, Leuven, Belgium.
⁵ Nuclear Medicine, University Hospitals Leuven, Leuven, Belgium.
⁶ Institute, Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium; Center for Microbiology, VIB, Leuven, Belgium.
⁷ Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium; Department of Endocrinology, University Hospitals Leuven, Leuven, Belgium.
⁸ Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium; Department of Endocrinology, University Hospitals Leuven, Leuven, Belgium. Electronic address: Christophe.matthys@kuleuven.be.

PMID: 36603693
DOI: 10.1016/j.ejpb.2022.12.018

Abstract

Background: Knowledge regarding the gastrointestinal physiology after sleeve gastrectomy and Roux-en-Y gastric bypass is urgently needed to understand, prevent and treat the nutritional and pharmacological complications of bariatric surgery.

Aim: To investigate the effect of sleeve gastrectomy and Roux-en-Y gastric bypass on gastrointestinal motility (e.g., transit and pressure), pH, and intestinal bile acid concentration.

Material and methods: An exploratory cross-sectional study was performed in six participants living with obesity, six participants who underwent sleeve gastrectomy, and six participants who underwent Roux-en-Y gastric bypass. During the first visit, a wireless motility capsule (SmartPill©) was ingested after an overnight fast to measure gastrointestinal transit, pH, and pressure. During the second visit, a gastric emptying scintigraphy test of a nutritional drink labeled with ^99mTc-colloid by a dual-head SPECT gamma camera was performed to measure gastric emptying half-time (GET_1/2). During the third visit, two customized multiple lumen aspiration catheters were positioned to collect fasting and postprandial intestinal fluids to measure bile acid concentration.

Results: Immediate pouch emptying (P = 0.0007) and a trend for faster GET_1/2 (P = 0.09) were observed in both bariatric groups. There was a tendency for a shorter orocecal transit in participants with sleeve gastrectomy and Roux-en-Y gastric bypass (P = 0.08). The orocecal segment was characterized by a higher 25th percentile pH (P = 0.004) and a trend for a higher median pH in both bariatric groups (P = 0.07). Fasting total bile acid concentration was 7.5-fold higher in the common limb after Roux-en-Y gastric bypass (P < 0.0001) and 3.5-fold higher in the jejunum after sleeve gastrectomy (P = 0.009) compared to obesity. Postprandial bile acid concentration was 3-fold higher in the jejunum after sleeve gastrectomy (P = 0.0004) and 6.5-fold higher in the common limb after Roux-en-Y gastric bypass (P < 0.0001) compared to obesity.

Conclusion: The anatomical alterations of sleeve gastrectomy and Roux-en-Y gastric bypass have an important impact on gastrointestinal physiology. This data confirms changes in transit and pH and provides the first evidence for altered intraluminal bile acid concentration.

Keywords: Bariatric surgery; Bile acids; Gastric emptying; Gastrointestinal pH; Gastrointestinal physiology; Gastrointestinal pressure; Gastrointestinal transit time; Roux-en-Y gastric bypass; Sleeve gastrectomy; Wireless motility capsule.

MeSH terms

Bile Acids and Salts
Cross-Sectional Studies
Gastrectomy / methods
Gastric Bypass* / methods
Humans
Obesity / complications
Obesity / surgery
Obesity, Morbid* / complications
Obesity, Morbid* / surgery

Substances

Bile Acids and Salts