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One-Anastomosis Gastric Bypass: First 407 Patients in 1 year



One-anastomosis gastric bypass (OAGB) is a promising laparoscopic procedure with various benefits including shorter operating times and less operative complications. That said, it is yet to gain widespread acceptance. Here, we describe our first-year experience with OAGB in our department, in particular the safety and efficacy of this procedure.


This study is a retrospective analysis of all patients who underwent OAGB between March 2015 and March 2016 by our bariatric surgery unit. Patient demographics, comorbidities, operative and postoperative data were collected and analyzed as well as outcomes during the first year.


Four hundred and seven patients underwent OAGB (254 females, average age 41.8 ± 12.05, BMI = 41.7 ± 5.77 kg/m2). Ninety-eight patients (24%) had prior bariatric surgery. Ninety-four patients (23%) had diabetes, 93 patients (22.8%) had hypertension, 123 (28.8%) had hyperlipidemia, and 35 patients (8.6%) suffered from obstructive sleep apnea. Eight patients (1.96%) had early minor complications (Clavien-Dindo 1–3a), and 10 patients (2.45%) suffered early major complications (Clavien-Dindo ≥3b). The average length of hospital stay was 2.2 ± 0.84 days (range 2–10 days). Twenty patients (4.8%) were readmitted, and 10 patients underwent reoperation. Patients who had had previous bariatric surgery had higher rates of complications, a prolonged hospital admission, higher rates of readmission, and early reoperations. The average excess weight loss (%EWL) 1 year following surgery was 88.9 ± 27.3 and 72.8 ± 43.5% in patients that underwent primary and revision OAGB, respectively.


OAGB is both safe and effective as a primary as well as a revision bariatric surgery.

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Correspondence to Yonatan Lessing.

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants included in the study.

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The authors declare that they have no conflict of interest.

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The Nikolas and Elizabeth Shlezak Fund for Experimental Surgery, Sackler Faculty of Medicine, Tel Aviv University 64239 Tel Aviv Israel

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Lessing, Y., Pencovich, N., Khatib, M. et al. One-Anastomosis Gastric Bypass: First 407 Patients in 1 year. OBES SURG 27, 2583–2589 (2017).

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  • Bariatric
  • Mini-gastric bypass
  • Sleeve gastrectomy
  • Obesity
  • BMI