Evaluation of the Efficacy of Single Anastomosis Sleeve Ileal (SASI) Bypass for Patients with Morbid Obesity: a Multicenter Study

  • Tarek Mahdy
  • Sameh Hany EmileEmail author
  • Amr Madyan
  • Carl Schou
  • Abdulwahid Alwahidi
  • Rui Ribeiro
  • Alaa Sewefy
  • Martin Büsing
  • Mohammed Al-Haifi
  • Emad Salih
  • Scott Shikora
Original Contributions



Single anastomosis sleeve ileal (SASI) bypass is a newly introduced bariatric and metabolic procedure. The present multicenter study aimed to evaluate the efficacy of the SASI bypass in the treatment of patients with morbid obesity and the metabolic syndrome.


This is a retrospective, seven-country, multicenter study on patients with morbid obesity who underwent the SASI bypass. Data regarding patients’ demographics, body mass index (BMI), percentage of total weight loss (%TWL), percentage of excess weight loss (%EWL), and improvement in comorbidities at 12 months postoperatively and postoperative complications were collected.


Among 605 patients who underwent the SASI, 54 were excluded and 551 (390; 70.8% female) were included. At 12 months after the SASI, a significant decrease in the BMI was observed (43.2 ± 12.5 to 31.2 ± 9.7 kg/m2; p < 0.0001). The %TWL was 27.4 ± 13.4 and the %EWL was 63.9 ± 29.5. Among the 279 patients with type 2 diabetes mellitus (T2DM), complete remission was recorded in 234 (83.9%) patients and partial improvement in 43 (15.4%) patients. Eighty-six (36.1%) patients with hypertension, 104 (65%) patients with hyperlipidemia, 37 (57.8%) patients with sleep apnea, and 70 (92.1%) patients with GERD achieved remission. Fifty-six (10.1%) complications and 2 (0.3%) mortalities were recorded. Most complications were minor. All patients had 12 months follow-up.


The SASI bypass is an effective bariatric and metabolic surgery that achieved satisfactory weight loss and improvement in medical comorbidities, including T2DM, hypertension, sleep apnea, and GERD, with a low complication rate.


Sleeve Ileal Single Anastomosis SASI Bypass Multicenter Morbid obesity 


Authors’ Contributions

Tarek Mahdy designed the study and participated in data collection, drafting, and revision of the manuscript. Sameh Emile and Amr Madyan conducted data analysis and wrote and revised the manuscript. Carl Scho, Abdulwahid Alwahidi, Rui Ribier, Alaa Elsewefy, Martin Busing, Mohammed AL-Haifi, and Emad Sali performed the procedures, followed the patients, collected the data, and revised the final manuscript. Scott Shikora participated in drafting and critical supervision of the manuscript.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Statement of Informed Consent

Informed consent was not required for this type of studies (retrospective review of data).

Statement of Human and Animal Rights

This study was conducted in accordance with the declaration of Helsinki. Ethical approval for the study was obtained from the Institutional Ethics Committee.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Tarek Mahdy
    • 1
  • Sameh Hany Emile
    • 1
    Email author
  • Amr Madyan
    • 1
  • Carl Schou
    • 2
  • Abdulwahid Alwahidi
    • 3
  • Rui Ribeiro
    • 4
  • Alaa Sewefy
    • 5
  • Martin Büsing
    • 6
  • Mohammed Al-Haifi
    • 7
  • Emad Salih
    • 8
  • Scott Shikora
    • 9
  1. 1.General Surgery Department, Mansoura Faculty of Medicine, Mansoura University HospitalsMansoura UniversityMansouraEgypt
  2. 2.Aker University HospitalOsloNorway
  3. 3.Sharjah University HospitalSharjahUnited Arab Emirates
  4. 4.Clinica De Santo AntonioLisbonPortugal
  5. 5.General Surgery Department, Minia Faculty of MedicineMinia UniversityMinyaEgypt
  6. 6.Klinikum VestRecklinghausenGermany
  7. 7.Sidra HospitalRiggae AreaKuwait
  8. 8.Atakent HospitalIstanbulTurkey
  9. 9.Brigham and Women’s HospitalHarvard Medical SchoolBostonUSA

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