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NCT Number: NCT04422405

Functional Changes in the Stomach and Esophagus After One Anastomosis Gastric Bypass- OAGB

Evaluation of the functional changes in the stomach and esophagus of patients undergoing One Anastomosis Gastric Bypass (OAGB)

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Key information

Conditions

Obesity, Morbid Body Weight Deglutition Disorders Digestive System Diseases Duodenal Diseases Esophageal Diseases Esophageal Motility Disorders GERD Gastroesophageal Reflux Gastrointestinal Diseases Intestinal Diseases Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Peptic Ulcer Signs and Symptoms Stomach Diseases Stomach Ulcer Ulcer, Gastric

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Limmattal Hospital

Schlieren, Canton of Zurich, 8952, Switzerland

Location status: Recruiting

Location contact

Urs Zingg, Prof.

CONTACT

[email protected]

+41 44 733 21 26

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • BMI> 35 kg/m2
  • 2 years of controlled conservative obesity treatment without weight reduction
  • patients should give their consent to participate in the study

Exclusion criteria

  • Less than 2 years of conservative obesity treatment
  • cancer
  • cirrhosis Child-Pough score A
  • Crohn's disease
  • serious psychiatric disorder, which led to in-hospital treatment in psychiatric clinic in the past two years
  • drug consumption
  • non-compliance
  • hiatal hernia > 4cm
  • gastric pouch < 10cm
  • Barett esophagus
  • erosive esophagitis Grade C or D according to the Los Angeles Classification
  • endoscopically proven gastric stricture
  • acid exposition time > 6% (Lyon criteria)
  • reflux episodes> 80 /24 hours (Lyon criteria)
  • insufficient low esophageal sphincter according to manometry findings
  • pathological findings in the impedance pH-metry (acid and non-acid reflux)

Treatment and study plan

One Anastomosis Gastric Bypass (OAGB)

Procedure

The procedure is performed laparoscopically. The "GIA" stapler divides the stomach at the junction of the body and antrum. An Ewald tube, roughly the diameter of the esophagus, is passed by the anesthetist and held against the lesser curvature. The division of the stomach against the tube is completed, with 5- 6 lines of staples. The division of the stomach is parallel to the lesser curvature and up to the angle of His. A point is selected on the small bowel about 200 cm distal to the ligament of Treitz. The jejunal loop is brought up antecolic, and the Endo-GIA stapler is used to perform the anastomosis between the stomach and the small bowel at this point. The distal end of the gastric tube is anastomosed to the side of the small bowel.

Other names: Mini-Gastric Bypass

Primary outcomes

  1. Marginal ulcer rates

    Time frame: 2 years post surgery

  2. Marginal ulcer rates

    Time frame: 5 years post surgery

  3. Assessment of age as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    Age of participants will be measured in years.

  4. Assessment of age as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    Age of participants will be measured in years

  5. Assessment of gender as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    The association between gender of participants (male/female) and incidence of marginal ulcers will be assessed.

  6. Assessment of gender as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    The association between gender of participants (male/female) and incidende of marginal ulcers will be assessed.

  7. Assessment of tobacco use as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the number of participants who are smokers correlates with the incidence of marginal ulcers.

  8. Assessment of tobacco use as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the number of participants who are smokers correlates with the incidence of marginal ulcers.

  9. Assessment of alcohol use as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the number of participants who report alcohol use correlates with the incidence of marginal ulcers.

  10. Assessment of alcohol use as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the the number of participants who report alcohol use correlates with the incidence of marginal ulcers.

  11. Assessment of nonsteroidal antiinflammatory drug (NSAID) use as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the number of participants who report NSAID use correlates with the incidence of marginal ulcers.

  12. Assessment of nonsteroidal antiinflammatory drug (NSAID) use as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the number of participants who report NSAID use correlates with the incidence of marginal ulcers.

  13. Assessment of immunosuppressive medication usage as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the number of participants who report immunosuppressive medication usage correlates with the incidence of marginal ulcers.

  14. Assessment of immunosuppressive medication usage as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the number of participants who report immunosuppressive medication usage correlates with the incidence of marginal ulcers.

  15. Assessment of Helicobacter pylori as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the incidence of Helicobacter pylori proven by biopsy correlates with the incidence of marginal ulcers.

  16. Assessment of Helicobacter pylori as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the incidence of Helicobacter pylori proven by biopsy correlates with the incidence of marginal ulcer.

  17. Assessment of gastroesophageal reflux disease (GERD) as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the incidence of GERD correlates with the incidence of marginal ulcers.

  18. Assessment of gastroesophageal reflux disease (GERD) as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the incidence of GERD correlates with the incidence of marginal ulcers.

  19. Assessment of diabetes mellitus as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the incidence of diabetes mellitus correlates with the incidence of marginal ulcers.

  20. Assessment of diabetes mellitus as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the incidence of diabetes mellitus correlates with the incidence of marginal ulcers.

  21. Assessment of dyslipidemia as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the incidence of dyslipidemia among the participants correlates with the incidence of marginal ulcers.

  22. Assessment of dyslipidemia as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the incidence of dyslipidemia among the participants correlates with the incidence of marginal ulcers.

  23. Assessment of coronary artery disease (CAD) as risk factor for marginal ulcer development

    Time frame: 2 years post surgery

    It will be assessed if the incidence of CAD among the participants correlates with the incidence of marginal ulcers.

  24. Assessment of coronary artery disease (CAD) as risk factor for marginal ulcer development

    Time frame: 5 years post surgery

    It will be assessed if the incidence of CAD among the participants correlates with the incidence of marginal ulcers.

Secondary outcomes

  1. Total weight loss % (TWL)

    Time frame: 2 years post surgery

  2. Total weight loss % (TWL)

    Time frame: 5 years post surgery

  3. Excess weight loss % (EWL)

    Time frame: 2 years post surgery

  4. Excess weight loss % (EWL)

    Time frame: 5 years post surgery

  5. Total BMI loss (TBL)

    Time frame: 2 years post surgery

  6. Total BMI loss (TBL)

    Time frame: 5 years post surgery

  7. Excess BMI loss (EBL)

    Time frame: 2 years post surgery

  8. Excess BMI loss (EBL)

    Time frame: 5 years post surgery

  9. Late morbidity (>30 days)

    Time frame: 30 days post surgery

    Number of surgical complications according to Dindo-Clavien classification

  10. Late morbidity (>30 days)

    Time frame: 5 years

    Number of surgical complications according to Dindo-Clavien classification

  11. Incidence of gastroesopagheal reflux disease (GERD)

    Time frame: 2 years post surgery

    based on upper gastrointestinal endoscopy findings and classified according to the Los Angeles Classification

  12. Incidence of gastroesopagheal reflux disease (GERD)

    Time frame: 5 years post surgery

    based on upper gastrointestinal endoscopy findings and classified according to the Los Angeles Classification

  13. Incidence of Barrett's esophagus

    Time frame: 2 years post surgery

    based on biopsy findings

  14. Incidence of Barrett's esophagus

    Time frame: 5 years post surgery

    based on biopsy findings

  15. Changes of esophageal motor function

    Time frame: 2 years post surgery

    The esophageal motor function will be measured in mmHg via high-resolution manometry.

  16. Changes of esophageal motor function

    Time frame: 5 years post surgery

    The esophageal motor function will be measured in mmHg via high-resolution manometry.

  17. Esophageal acid or bolus exposure

    Time frame: 2 years post surgery

    Measured with impedance-pH Monitoring. Acid exposure (%) is defined as the total time the pH is < 4 divided by the time monitored. Bolus exposure (%) is defined as being analogous to acid exposure by adding the duration of all four reflux subcategories defined by the impedance, and dividing this value by the time monitored.

  18. Esophageal acid or bolus exposure

    Time frame: 5 years post surgery

    Measured with impedance-pH Monitoring. Acid exposure (%) is defined as the total time the pH is < 4 divided by the time monitored. Bolus exposure (%) is defined as being analogous to acid exposure by adding the duration of all four reflux subcategories defined by the impedance, and dividing this value by the time monitored.

  19. Number of acid or alcaline reflux events

    Time frame: 2 years post surgery

    Measured with impedance-pH Monitoring.

  20. Number of acid or alcaline reflux events

    Time frame: 5 years post surgery

    Measured with impedance-pH Monitoring.

  21. Gastrointestinal quality of life (QoL): GIQLI

    Time frame: 2 years post surgery

    The gastrointestinal (QoL) will be measured using the Gastrointestinal Quality of Life Index (GIQLI). The GIQLI is a validated tool to assess health- related quality of life of patients with gastrointestinal disease or patients who undergo gastrointestinal operations. Its scale is 0-128. Higher values indicate a better quality of life outcome.

  22. Gastrointestinal quality of life (QoL): GIQLI

    Time frame: 5 years post surgery

    The gastrointestinal (QoL) will be measured using the Gastrointestinal Quality of Life Index (GIQLI). The GIQLI is a validated tool to assess health- related quality of life of patients with gastrointestinal disease or patients who undergo gastrointestinal operations. Its scale is 0-128. Higher values indicate a better quality of life outcome.

  23. Obesity- related quality of life (QoL): BAROS

    Time frame: 2 years post surgery

    Obesity- related QoL will be measured with the BAROS (Bariatric Analysis and Reporting Outcome System). BAROS consists of a scoring table that includes three columns with the main areas of interest: weight loss, improvement of medical conditions, and QoL. A maximum of three points is given in each domain to evaluate changes after medical intervention (maximum score is 9 points). Higher scores indicate a better outcome.

  24. Obesity- related quality of life: BAROS

    Time frame: 5 years post surgery

    Obesity- related QoL will be measured with the BAROS (Bariatric Analysis and Reporting Outcome System). BAROS consists of a scoring table that includes three columns with the main areas of interest: weight loss, improvement of medical conditions, and QoL. A maximum of three points is given in each domain to evaluate changes after medical intervention (maximum score is 9 points). Higher scores indicate a better outcome.

  25. Reflux-associated symptoms

    Time frame: 2 years post surgery

    GERD symptoms will be measured with the Gastroesophageal reflux disease questionnaire (GERDQ). GERDQ has a scale between 0 and 18 points. Increasing scores correlate with increasing severity of heartburn symptoms.

  26. Reflux-associated symptoms

    Time frame: 5 years post surgery

    GERD symptoms will be measured with the Gastroesophageal reflux disease questionnaire (GERDQ). GERDQ has a scale between 0 and 18 points. Increasing scores correlate with increasing severity of heartburn symptoms.

  27. Reflux-associated quality of life (QoL): GERD-HRQL

    Time frame: 2 years post surgery

    Reflux- associated QoL will be assessed with the Health-related QoL scale for GERD (GERD-HRQL). The scale has 11 items, which focus on heartburn symptoms, dysphagia, medication effects and the patient's present health condition. Each item is scored from 0 to 5, with a higher score indicating a better QoL.

  28. Reflux-associated quality of life (QoL): GERD-HRQL

    Time frame: 5 years post surgery

    Reflux- associated QoL will be assessed with the Health-related QoL scale for GERD (GERD-HRQL). The scale has 11 items, which focus on heartburn symptoms, dysphagia, medication effects and the patient's present health condition. Each item is scored from 0 to 5, with a higher score indicating a better QoL.

Study contacts

Contact information is provided by the study sponsor or research team.

Urs Zingg, MD, Prof.

CONTACT

[email protected]

+41 44 733 21 26

Sponsors and collaborators

Lead sponsor

Spital Limmattal Schlieren

Other

Registry information

Official study title

Functional Changes in the Stomach and Esophagus After One Anastomosis Gastric Bypass- OAGB- BiFlux Trial

Acronym: BiFLux

Important dates

Study start
2020
Primary completion
2035
Study completion
2035
First posted
Jun 9, 2020
Registry last updated
Jun 6, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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