Background During the last two decades, an increasing number of bariatric surgical procedures have been performed worldwide. There is no consensus regarding optimal perioperative care in bariatric surgery. This review aims to present such a consensus and to provide graded recommendations for elements in an evidence-based ''enhanced'' perioperative protocol. Methods The English-language literature between January 1966 and January 2015 was searched, with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohort studies. Selected studies were examined, reviewed and graded. After critical appraisal of these studies, the group of authors reached a consensus recommendation. Results Although for some elements, recommendations are extrapolated from non-bariatric settings (mainly colorectal), most recommendations are based on good-quality trials or meta-analyses of good-quality trials. Conclusions A comprehensive evidence-based consensus was reached and is presented in this review by the enhanced recovery after surgery (ERAS) Society. The guidelines were endorsed by the International Association for Surgical Metabolism and Nutrition (IASMEN) and based on the evidence available in the literature for each of the elements of the multimodal perioperative care pathway for patients undergoing bariatric surgery.

Sleeve gastrectomy (SG) is a commonly performed bariatric procedure. Weight regain following SG is a significant issue. Yet the defining, reporting and understanding of this phenomenon remains largely neglected. Systematic review was performed to locate articles reporting the definition, rate and/or cause of weight regain in patients at least 2 years post-SG. A range of definitions employed to describe weight regain were identified in the literature. Rates of regain ranged from 5.7 % at 2 years to 75.6 % at 6 years. Proposed causes of weight regain included initial sleeve size, sleeve dilation, increased ghrelin levels, inadequate follow-up support and maladaptive lifestyle behaviours. Bariatric literature would benefit from standardising definitions used to report weight regain and its rate in clinical series. Larger prospective studies are required to further understand mechanisms of weight regain following SG.

Background: Optimized perioperative care within an enhanced recovery after surgery (ERAS) protocol is designed to reduce morbidity after surgery, resulting in a shorter hospital stay. The present study evaluated this approach in the context of sleeve gastrectomy for patients with morbid obesity.Methods: Patients were allocated to perioperative care according to a bariatric ERAS protocol or a control group that received standard care. These groups were also compared with a historical group of patients who underwent laparoscopic sleeve gastrectomy at the same institution between 2006 and 2010, selected using matched propensity scores. The primary outcome was median length of hospital stay. Secondary outcomes included readmission rates, postoperative morbidity, postoperative fatigue and mean cost per patient.Results: Of 116 patients included in the analysis, 78 were allocated to the ERAS (40) or control (38) group and there were 38 in the historical group. There were no differences in baseline characteristics between groups. Median hospital stay was significantly shorter in the ERAS group (1 day) than in the control (2 days; P < 0·001) and historical (3 days; P < 0·001) groups. It was also shorter in the control group than in the historical group (P = 0·010). There was no difference in readmission rates, postoperative complications or postoperative fatigue. The mean cost per patient was significantly higher in the historical group than in the ERAS (P = 0·010) and control (P = 0·018) groups. Conclusion:The ERAS protocol in the setting of bariatric surgery shortened hospital stay and was cost-effective. There was no increase in perioperative morbidity. Registration number: NCT01303809 (http://www.clinicaltrials.gov).

There is debate over the ethical basis for prioritization. It is a concern that it is not addressed in many studies. The development of generic criteria showed a dearth of consensus approaches that represents a significant gap in our knowledge. On the aspects of summation and weighting, the impact of assumptions on the prioritization of patients may not have been fully explored.