Bariatric techniques for bypass surgery evolve constantly. Switching from one well-established protocol to another in a running surgical teaching program is challenging. We analyzed clinical outcomes, safety and costs at a single bariatric center transitioning from circular to an augmented linear bypass protocol.

Between 2011 and 2018, 454 patients were included in this retrospective study. The circular bypass protocol (CIRC; n=177) was primarily used between 2011-2012. Between 2013-2015 the transition occurred. Thereafter, the augmented linear protocol (aLIN; n=277) was primarily utilized.

Overall, mean preoperative BMI dropped from 42.2 kg/m2 to 29.6 kg/m2 after 5 years with no difference between groups. Operation times were significantly shorter in the aLIN-group, compared with CIRC-patients at 108 (±32) vs. 120 (±34) minutes (P<0.001), respectively. The reoperation rate was significantly higher in the CIRC vs. aLIN group at n=65 (36%) vs. n=35 (13%; P<0.001), respectively. Specifically, revision due to internal hernia occurred much more frequently in the CIRC-group, n=36 (20%) vs. n=12 (4%; P<0.001). Moreover, reoperation due to gastrojejunostomy-leakage and endoscopic dilatation for anastomotic stenosis was more common in the CIRC vs. aLIN group (P<0.001). Adjusted overall cost per case was lower in aLIN-patients at 15,403 (±7,848) vs. CIRC-patients at 18,525 (±7,850) Swiss Francs (P<0.001). Overall profit was 2,555 ± 4,768 vs. 1,455 ± 5,638 Swiss Francs in the aLIN vs. CIRC-group, respectively (P=0.026).

This study showed improved clinical outcomes while also secondarily improving financial performance after a gradual transition from a circular stapling protocol to an augmented linear stapling protocol in proximal gastric bypass surgery. The technical transition in this study proves, that if a new technique is superior in terms of safety and postoperative morbidity, it will also be financially beneficial.