{"paper_id":"00a64459-511f-435c-9bfa-65e821e94f0c","body_text":"Re-Appraisal Learning Curve of Laparoscopic Roux-En Y Gastric Bypass: Results of One Hundred and Eight Cases From A Low Volume Unit | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research article Re-Appraisal Learning Curve of Laparoscopic Roux-En Y Gastric Bypass: Results of One Hundred and Eight Cases From A Low Volume Unit Hung Chieh Lo, Sheng-Mao Wu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-103556/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 15 Feb, 2021 Read the published version in BMC Surgery → Version 1 posted 11 You are reading this latest preprint version Abstract Background The study aim was to reevaluate the learning curve of laparoscopic Roux-en Y gastric bypass (LRYGB) in the modern era considering a single surgeon’s experience. Methods Except those with body mass index (BMI) >50 kg/m 2 needs further discussion; all other patients who met the regional criteria and underwent primary LRYGB were retrospectively enrolled. Those who underwent surgery in 2016-17, 2018 and 2019 by a single surgeon with 10+ years of laparoscopic experience were assigned to groups A, B and C, respectively. Patient demographics and 30-day outcome data, including operation time, length of stay (LOS), emergency room visits, readmission, and reoperation, were compared between groups. Results One hundred and eight patients met the inclusion criteria; 36, 38, and 34 patients were assigned to groups A, B and C, respectively. There were no differences in age, sex distribution or common comorbidities between groups, except group B had a lower BMI (35.1 kg/m 2 vs. 37.0 kg/m 2 ) and a higher rate of hypertension (44.7% vs. 22.2%) than group A. The operation time was markedly reduced (96.1 min and 114.9 min, respectively), and the LOS was shortened (2.2 days and 2.9 days, respectively) in group B compared to group A and remained stationary in group C, with no further reduction in 30-day complications. Conclusion The learning process for LRYGB can be shortened to approximately 30 cases if conducted selectively and by experienced laparoscopic surgeons. Further follow-up is required to verify the long-term safety and its applicability to other patient subgroups. Surgery General Surgery Obesity Roux-en Y Gastric Bypass Bariatric Learning curve Background The prevalence of obesity has nearly tripled over the past four decades[ 1 ]. Bariatric surgery has been shown to be the only treatment with long-term effectiveness for morbid obesity and obesity-related comorbidities [ 2 ]. Until recently, laparoscopic Roux-en Y gastric bypass (LRYGB) was the standard bariatric-metabolic procedure and was performed secondarily after laparoscopic sleeve gastrectomy (LSG) [ 3 ]. However, it is generally considered more technically demanding and has higher complication rates than LSG [ 4 ]. Accordingly, a steep learning curve (LC) was generally required to meet its safety standards[ 5 ]. As a result, only a handful of studies have addressed the learning process in a low-volume center [ 6 ]. Traditionally, surgical procedures were mostly learned through observation, on-the-spot assistance or field practice. As time progressed, new era of surgical education platforms emerged[ 7 ]. Online media resources are frequently used to facilitate and improve the learning process [ 8 ] and served as valuable method in our learning process. Starting with one-anastomosis gastric bypass (OAGB-MGB), we then modify our practice because arguments and controversies emerged such as the long-term consequences of bile reflux and nutrition problems [ 9 ]. As practicing laparoscopic surgeons with 10 + years of experience in various gastrointestinal surgeries and proficient in suturing techniques, we deemed we were ready to incorporate LRYGB as our treatment modality after attending education courses, dry lab training and conferences consisting of live demonstrations as well as applying our initial successive experience in performing OAGB-MGB[ 10 ]. Moreover, since Wittgrove et al . first established LRYGB [ 11 ], several vital steps of the original technique have been modified. For example, the preferable placement of the Roux limb has changed from the retro-gastric/retro-colic [ 12 , 13 ] to the ante-colic position. Common techniques utilized in gastrojejunostomy have shifted from circular-stapled [ 12 , 14 , 15 ] to linear-stapled anastomosis or a total hand sewn technique. To address enterotomy defects, the method shifted from stapled closure [ 15 ] to perform a sutured closure to avoid stenosis. There is a tendency to routinely closure of mesentery defects; however, in the past, some choose to left open for technical reasons [ 16 ]. The aim of this study was to reappraise the learning curve of LRYGB under the aforementioned modern background in a low-volume unit. Our primary goal was to verify its safety according to the proficiency of medical staff, with a focus on 30-day per-operative outcomes. Methods From January 2016 to December 2019, all data of consecutive patients who underwent primary LRYGB under the care of a single surgeon were collected retrospectively from a prospectively maintained database after obtaining institutional review board approval. Patients were eligible for inclusion if they met the regional criteria proposed by the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) [ 17 ]. There are no specific selection criteria except a body mass index (BMI) >50 kg/m 2 , as gastric bypass is generally less effective in these patients [ 18 ] , and they have a higher rate of complications than patients with a lower BMI [ 19 ]. Nevertheless, the final decision was made using a shared decision-making process after fully considering the benefits, risks and potential long-term outcomes of each procedure. To assess the learning process, patients were divided into three groups based on their surgery time and case distributions: group A included initial patients who underwent primary LRYGB during 2016-17. Groups B and C included patients who underwent surgery during 2018 and 2019, respectively. All patients underwent complete preoperative evaluations. The recorded parameters included patient demographic factors and anthropometric data as well as all relevant outcome measures, including the operation time, length of stay (LOS) and 30-day complications, such as emergency room (ER) visit, readmission, reoperation and conversion. Surgical technique LRYGB was performed with a four-abdominal trocar technique and a Nathanson liver retractor. This surgical technique utilized a linear stapler to create a lesser curve-based, 30-ml vertical gastric pouch over a 32 Fr. calibrating tube with 100-cm ante-colic, ante-gastric Roux limb and 100-cm biliopancreatic limb. The enterotomies for both anastomoses were hand-sewn closed. Both mesenteric defects were routinely closed with nonabsorbable sutures. Data collection and statistical analysis The Statistical Package for the Social Sciences software version 20.0 (SPSS Inc., Chicago, Illinois, USA) was used to perform the statistical analyses. Descriptive results regarding continuous variables are presented as the means ± standard deviations, and categorical variables are presented as counts and percentages. Data were analyzed using Fisher’s exact test for categorical data, and the unpaired t test was used for parametric data when appropriate. Tests for statistical significance were two-sided, with a level of significance of 0.05. Results From January 2016 to December 2019, a total of two hundred and four patients underwent bariatric or metabolic procedures in our unit. Among them, three patients underwent a nonprimary procedure, five patients underwent LSG, and 39 patients underwent OAGB-MGB during 2016-17. In 2018, two patients underwent a nonprimary procedure; two patients underwent LSG, and 18 patients underwent OAGB-MGB. In 2019, six patients underwent a nonprimary procedure; one patient underwent LSG, and 20 patients underwent OAGB-MGB. All the patients who did not fulfill the inclusion criteria were excluded from the analysis, leaving one hundred and eight patients enrolled in this study. Of these, 36 patients who underwent primary LRYGB during 2016-17 were assigned to group A. The other 38 and 34 patients who underwent primary LRYGB in 2018 and 2019 were assigned to group B and group C, respectively. The demographic details and clinical characteristics are outlined in Table 1. There were no significant differences between group B and group A with respect to age, sex, preoperative weight or incidence of common comorbidities. However, patients in group B had a significantly lower BMI (35.1 ± 3.8 kg/m 2 vs. 37.0± 3.6 kg/m 2 ; p=0.03) and had a higher rate of hypertension (HTN) (44.7% vs. 22.8%; p=0.04) than those in group A. Group C was not different in terms of age, female proportion, or baseline BMI than group B, but group C had a tendency toward a higher rate of diabetes mellitus (32.4% vs. 21.1%; p=0.28) and a lower rate of HTN (35.3% vs. 44.7%; p=0.41) than group B. The surgical characteristics and outcomes are listed in Table 2. As shown, only one concomitant procedure, partial gastrectomy for benign lesions, was carried out in group A. The mean operation time was significantly decreased in group B compared to group A (96.1 min vs. 114.9 min, respectively; p<0.001) and was similar between group B and group C (96.1 min vs. 92.1 min; p=0.20). The mean LOS was also markedly shortened in group B compared to that in group A (2.2 ± 0.5 days vs. 2.9 ± 0.8 days; p < 0.001) and was similar, at 2.2 days, between group C and group B (p=0.70). All procedures were complete with a laparoscopic approach without open conversion. The rate of 30-day complications was not different between groups B and A (2.6% vs. 2.8%; p= 0.97) or between groups C and B (2.9% vs. 2.6%; p=0.62). A total of five patients experienced 30-day adverse events and three of them were classified as with complications. One patient in group A was readmitted for gastrojejunostomy stenosis on postoperative day (POD) 30, which was relieved under a single session of balloon dilatation. In group B, two patients visited the ER after discharge; one visited for nonspecific focal abdominal pain. Another patient with hematemesis on POD 9 was readmitted and recovered uneventfully after proper medical treatment. In group C, one patient was noted to have self-limiting melena that subsided under supportive treatment. Another patient visited the ER for lower back pain. The rates of 30-day ER visits and 30-day readmission were not different between the groups. There was no reported anastomotic leakage, reoperation or mortality throughout the study period. Discussion Herein, we reported the outcomes of initial 108 patients who underwent LRYGB over a 4-yr period in a low-volume hospital, indicating LC. Comparing the results among the 3 groups; significant improvements in the operation time and LOS with an acceptably low rate of complications was observed after the initial 36 cases (group A). The present study demonstrated that the LC of LRYGB can be safely reduced to 30 + cases in the modern era under a unique setting. Because of increasingly complex techniques and the dependence on advanced instruments, the acquisition of new laparoscopic skills is considered to be difficult. When conducting LRYGB in morbidly obese patients, there are likely several other inherent technical barriers, such as body habitus, multistep reconstructive procedures that involve multi-abdominal quadrants and laparoscopic suturing and knot tying skills. Therefore, it was once rated as a 9.5 on a difficulty scale of 10, indicating substantial technical difficulty[ 20 ]. These skill-related prerequisites can result in adverse consequences in the early phase of practice, especially in a low-volume practice [ 6 ]. Traditionally, various educational programs, such as workshops[ 21 ], bariatric fellowships[ 22 ] and systematic training programs[ 23 ], have been available to facilitate this process. In recent years, new-era platforms have emerged, providing another kind of auxiliary training approach[ 7 ]. Their popularity among medical professionals has been increasing, as they generally enable more visual and auditory interactions than journals or text books [ 24 ]. A systematic review for the impact of e-learning demonstrates significant gains in knowledge compared with traditional teaching patterns [ 25 ]. In our self-learning process, apart from traditional learning methods, these online multimedia materials provide considerable references and guidance despite the lack of objective tools for gauging their impact. Considering a single surgeon’s perspective, we retrieved comparative data in the literature discussing the relevant process by a single surgeon (Table 3). Among them, variability in surgical techniques exists. Moreover, several modifications of traditional methods have occurred, such as retro-colic placement of the Roux limb [ 12 , 13 ] or a circular-stapled anastomosis [ 12 , 14 , 15 ] had largely been fall out of favor. Meanwhile, there are differences among studies in terms of backgrounds, annual hospital volumes or former laparoscopic/bariatric experience levels. Though with undisputable importance and heightened awareness for proper fellowship training [ 26 ], there is no standard approach of teaching provided and accredited bariatric programs are not globally available. For example, while carried out during different periods, some hospitals conduct other laparoscopic bariatric procedures [ 27 , 28 ] or perform open bariatric surgeries beforehand [ 13 ], others just started after complete with fellowship training [ 14 , 16 ] or are based solely on advanced laparoscopic skills [ 12 , 15 , 29 ]. Additionally, there were with considerably different case selection criteria. In general, fellowship trained bariatric surgeons or those conduct after preceding bariatric experience appears to have a shorter LC and implement a more efficient practice. For instance, after completing a month-long mini-fellowship, Shen et al . achieved a considerably decreased complication rate and proficiency after only 30 cases [ 16 ]. In particular, they utilized the case selection criteria following IFSO Asian-Pacific guidelines, similar to our research [ 17 ]. However, they reported an initial complication rate of 26.7%, which included a 6.7% conversion, 10% reoperation and 5% leakage rate. While surgeons at high-volume hospitals often have the opportunity to master the procedure in a short period of time with preferable results [ 30 ], Shin et al . participated as assistants in 30 surgeries and conducted the first few surgeries under proctoring. They analyzed their first one hundred cases within 5 months and concluded that the LC plateaued after 50 surgeries [ 14 ]. While they realize with marked decreasing operation times (113 min pre-LC and 73 min post-LC), they indicated that there was no further notable reduction in complications after the LC. With particularly vast prior experience in LAP BAND ®, Ballesta-Lopez et al . also published a large series with marked decreased operative time and LOS after the first 100 surgeries[ 28 ]. Particularly, as one of only two studies, in addition to that by Andrew et al . [ 13 ], which were conducted with totally hand-sewn gastrojejunostomy, they reported a no negligible leakage rate of up to 9%, a 5.1% reoperation rate (mostly for leakage) and a 29.2% complication rate. In other studies with only prior advanced laparoscopic experience [ 12 , 15 , 29 ], the LC took slightly longer, and there was a substantially prolonged operation time compared with studies involving surgeons who completed a fellowship [ 14 , 16 , 27 ]. For instance, Oliak et al . reported a series with the highest mean BMI of 51 kg/m 2 and proposed that the LC plateaued after 75 surgeries[ 12 ]. Surgeons’ operative times decreased substantially from 189 min during the first 75 cases and then decreased gradually. Notably, the perioperative complication rates were substantial among all studies both before (32%) and after LC (15%). Nguyen et al . evaluated 150 consecutive cases, with the longest mean operation time of 250 min before LC; they too observed that an initial lack of experience (< 75 cases) was a major factor associated with major complications and an increased reoperation rate [ 15 ]. On the other hand, with advanced laparoscopic skills and preemptive bariatric experience; Agrawal et al . suggest that LRYGB can be performed safely with minimal complications of only 1.4% and effectively without any LC required[ 27 ]. It is noticeable that our initial result stabilized after just 36 surgeries and we had a low initial 30-day complication rate of 2.8%. Only the difference is their research was after completion of fellowship training[ 27 ]. However, concordant with these forenamed studies, a sharp improvement in terms of operation time was observed in current study after LC. As findings of Shin et al. [ 14 ], we observed no further decrease in the complication rate after LC. Only one patient presented with stenosis, and two other patients presented with hemorrhagic complications: one with hematemesis and one with melena. Considering the reported stenosis rate between 2.2% and 10% [ 12 , 14 , 16 , 29 ] and the hemorrhagic complication rate ranges from 1–3.3% during the learning process [ 14 , 15 , 29 ], we deemed our initial results to be acceptable. Furthermore, there was no mortality, leakage, conversion or other major complications. While prolonged hospital stay is not uncommon after such a procedure. Nguyen et al . noted that 11% of their cases had LOS over 4 days [ 15 ] , and the LOS is reported to range between 6 to 6.4 days before the LC and 4.8 to 5 days after the LC[ 16 , 29 ]. We observed a notably shorter LOS, with a mean of 2.9 days before the LC and 2.2 days thereafter. In addition, only 2.8% of our patients required hospitalization for more than 3 days. Our LC and timespan to reach competency are in line with findings from a systemic review that reported between 30–70 surgeries [ 31 ]. It is worth mention that the consistent outcome obtained in group B and group C can be considered an early achievement of proficiency because we reached this goal within less than 70 accumulative surgeries, while historically, it usually takes between 70–150 surgeries[ 31 ]. There are likely many factors contributing to our early desirable results. First, in contrast to most studies with an unselective patient approach [ 13 – 15 , 28 , 29 ], patients with a BMI > 50 were preferably offered alternative treatment modalities considering safety and long-term effectiveness [ 18 , 32 ]. As a result of this selective approach, the mean BMI of 36.1 kg/m 2 in our series was significantly lower than former studies, which ranged from 43 to 51 kg/m 2 [ 12 , 29 ]. Second, as guidelines regarding tailored per-operative care were established in 2016 [ 33 ], a pragmatic enhanced recovery protocol was gradually adopted in our unit ever since. Furthermore, our preceding experience in OAGB-MGB may transferred to subsequent LRYGB and increase its safety [ 10 ]. Likewise, comprehensive care and improved techniques have been demonstrated in other studies across different periods [ 34 ]. Because only two aforementioned studies included cases after 2010[ 16 , 27 ], we believe that general improvements further contribute to this desirable result. Limitations Limited by the selective approach, our result may not be generalizable for all patient subgroups. Nevertheless, a desirable outcome can be accomplished during the learning process via this selective approach. Moreover, because of its retrospective design and nonrandomized nature, the presence of clinical heterogeneity between groups may compromise its comparativeness. Conclusion In conclusion, a gradual LC for LRYGB with acceptably low complication rate, shortened operation time and LOS can be achieved in unique settings. Additional data regarding long-term efficacy, safety and generalizability are required. List of Abbreviations LRYGB, Laparoscopic Roux-en Y gastric bypass; BMI, body mass index; LOS, length of stay; LSG, laparoscopic sleeve gastrectomy; LC, learning curve; OAGB-MGB, one-anastomosis gastric bypass; IFSO, International Federation for the Surgery of Obesity and Metabolic Disorders; ER, emergency room; HTN, hypertension; POD, postoperative day; Declarations Ethical approval and consent to participate All procedures performed in studies involving human participants were in accordance with the ethical standards of institutional and/or national research committees and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. The research project was approved by local Institutional Review Board. Informed consent was waived because no data regarding the cases were disclosed. Consent for publication Written informed consent for publication was waived because no clinical details and/or clinical images regarding the cases were disclosed. Availability of data and materials The datasets generated during and/or analyzed during the current study are not publicly available due to restrictions from local Institutional Review Board but are available from the corresponding author on reasonable request and with permission from the local Institutional Review Board. Competing interests The authors declare that they have no competing interests . Funding The study was not sponsored and funded by any funding. Authors' contributions Hung-Chieh Lo designed the study, performed the surgical procedures, followed the patients, and participated in the data analysis and writing of the manuscript. Sheng-Mao Wu contributed to the data analysis. 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Lee WJ, Almalki OM, Ser KH, Chen JC, Lee YC: Randomized Controlled Trial of One Anastomosis Gastric Bypass Versus Roux-En-Y Gastric Bypass for Obesity: Comparison of the YOMEGA and Taiwan Studies . Obes Surg 2019, 29 (9):3047-3053. Tables Table 1. Demographic and clinical characteristics of the patients, mean (SD) Group A (N=36) Group B (N=38) Group A vs. B p-value Group C (N=34) Group B vs. C p-value Age (years) 35.3 ±10.3 38.5 ± 9.1 0.16 39.6 ± 9.2 0.62 Sex, n (%) 14 (38.9) 22 (61.1) 15 (39.5) 23 (60.5) 15 (44.1) 19 (55.9) 0.69 Male 0.96 Female Preoperative weight (kg) 102.8 ± 16.7 95.8 ± 17.1 0.08 98.7 ± 16.0 0.44 BMI (kg/m 2 ) 37.0 ± 3.6 35.1 ± 3.8 0.03 ✽ 36.3 ± 3.2 0.13 Comorbidities, n (%) Diabetes mellitus 10 (27.7) 8 (21.1) 0.50 11 (32.4) 0.28 Hypertension 8 (22.2) 17 (44.7) 0.04 ✽ 12 (35.3) 0.41 Dyslipidemia 18 (50) 21 (55.3) 0.65 18 (52.9) 0.84 BMI, Body mass index Data are expressed as the means ± standard deviations or as numbers and percentages Table 2. Surgical perspectives and outcomes, mean (SD) Group A (N=36) Group B (N=38) Group A vs. B p-value Group C (N=34) Group B vs. C p-value Concomitant procedure, n (%) 1(2.8) 0 0.30 0 Op time (min) 114.9 ± 29.1 96.1 ± 13.5 < 0.001 ✽ 92.1 ± 12.1 0.20 LOS (days) 2.9 ± 0.8 2.2 ± 0.5 < 0.001 ✽ 2.2 ± 0.4 0.70 Conversion 0 0 0 30-day complications, n (%) 1 (2.8) 1 (2.6) 0.97 1 (2.9) 0.62 Stenosis 1 0 0 Melena 0 0 1 Hematemesis 0 1 0 30-day ER visit, n (%) 0 2 (5.3) 0.16 1 (2.9) 0.62 30-day Readmission, n (%) 1 (2.8) 1 (2.6) 0.97 0 0.34 30-day Mortality, n (%) 0 0 0 Op, Operation; LOS, Length of stay; ER, Emergency room Table 3. List of historical studies involving a single surgeon Authors Study period Background Patients (n) Groups inclusion criteria Age a (years)/ BMI a (kg/m 2 ) LC Mean Op time (min) Complications (%) Pre- LC Post- LC Pre- LC Post- LC Agrawal et al . [ 27 ] 10-11 Advanced scope fellowship laparoscope bariatric 74 1 group primary procedures 45.1 47.7 Not required 160 n/a 1.4 n/a Shen et al . [ 16 ] 09-11 Advanced scope fellowship 60 2 groups IFSO-APCcriteria b 34.2 41.5 30 120 80 26.7 6.7 Shin et al . [ 14 ] 03 Advanced scope fellowship 100 2 groups unselective 42.6 47.6 50 113 73 32 8 Oliak et al . [ 12 ] 99-01 Advanced scope 225 3 groups primary procedures 40 51 75 189 125 32 15 Huang et al . [ 29 ] 05-07 Advanced scope 100 2 groups unselective 31.2 43 50 217 105 15 3 Nguyen et al . [ 15 ] n/a Advanced scope 150 2 groups unselective 40 47 75 250 n/a 12 1 Andrew et al . [ 13 ] 02-04 Open bariatric 201 3 groups unselective 37 49.2 70 145 118 19.4 11.9 Ballesta-Lopez et al . [ 28 ] 00-04 Advanced scope LAP BAND® 600 6 groups unselective 38.7 44.4 100 166 109 29.2 14 Current study 16-19 Advanced scope laparoscope bariatric 108 3 groups primary procedures 37.8 36.1 30+ 115 96 2.8 2.6 LC, Learning curve; Op, Operation; BMI, Body mass index; n/a, No data available a Mean b IFSO-APC criteria stands for International Federation for the Surgery of Obesity and Metabolic Disorders Asia Pacific Chapter criteria [ 17 ] Cite Share Download PDF Status: Published Journal Publication published 15 Feb, 2021 Read the published version in BMC Surgery → Version 1 posted Editorial decision: Minor revision 15 Dec, 2020 Review # 1 received at journal 14 Dec, 2020 Review # 2 received at journal 08 Dec, 2020 Reviewer # 3 agreed at journal 29 Nov, 2020 Reviewer # 2 agreed at journal 21 Nov, 2020 Reviewer # 1 agreed at journal 15 Nov, 2020 Reviewers invited by journal 12 Nov, 2020 Editor assigned by journal 27 Oct, 2020 Submission checks completed at journal 27 Oct, 2020 Editor invited by journal 27 Oct, 2020 First submitted to journal 26 Oct, 2020 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-103556\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research article\",\"associatedPublications\":[],\"authors\":[{\"id\":4596759,\"identity\":\"7b13818e-44c4-4d18-89c8-301826ca4c1c\",\"order_by\":0,\"name\":\"Hung Chieh Lo\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIie3SMUvEMBTA8ReUdMmRNYfYfoWWgov9MOny/BpxiYty621+BV3E8eBhpnOv6HC3dBM6yQkVTW+6JZhRMP/hZcmPRyAAqdQfbdCw8sfRCpiJE2y5J5zrA6J/IbAnoowj8up5azbjWyFvrz/U52OTQ0ZPd2xHQaLWF5VpbV8t3exhfrPGGgRiBzpMSsBs0xrS4ImaWWqNEmeevIaJ7JnRI+nCiX7+FUUUesJJl07wk6gtqvNbWkvVvcP6/NRizae3aPwOErlAdrkbqciJti/vtsllRq4bGgySw47VNPk0dBTwP2aIvJhKpVL/rB8eFVngAvB99wAAAABJRU5ErkJggg==\",\"orcid\":\"https://orcid.org/0000-0001-6079-8657\",\"institution\":\"Taipei Municipal Wanfang Hospital\",\"correspondingAuthor\":true,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Hung\",\"middleName\":\"Chieh\",\"lastName\":\"Lo\",\"suffix\":\"\"},{\"id\":4596760,\"identity\":\"56e4a67e-8305-4343-b255-8b2fb8307a32\",\"order_by\":1,\"name\":\"Sheng-Mao Wu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Taipei Municipal Wan-Fang Hospital\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Sheng-Mao\",\"middleName\":\"\",\"lastName\":\"Wu\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2020-11-05 17:12:50\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-103556/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-103556/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1186/s12893-021-01058-w\",\"type\":\"published\",\"date\":\"2021-02-15T15:00:30+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":13613608,\"identity\":\"98055472-da0c-4355-b4b6-0df29ba0f5e0\",\"added_by\":\"auto\",\"created_at\":\"2021-09-17 06:37:43\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1032180,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-103556/v1/940771e1-00ec-407e-a70d-df02837f840f.pdf\"}],\"financialInterests\":\"\",\"formattedTitle\":\"\\u003cp\\u003eRe-Appraisal Learning Curve of Laparoscopic Roux-En Y Gastric Bypass: Results of One Hundred and Eight Cases From A Low Volume Unit\\u003c/p\\u003e\",\"fulltext\":[{\"header\":\"Background\",\"content\":\" \\u003cp\\u003eThe prevalence of obesity has nearly tripled over the past four decades[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e]. Bariatric surgery has been shown to be the only treatment with long-term effectiveness for morbid obesity and obesity-related comorbidities [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]. Until recently, laparoscopic Roux-en Y gastric bypass (LRYGB) was the standard bariatric-metabolic procedure and was performed secondarily after laparoscopic sleeve gastrectomy (LSG) [\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]. However, it is generally considered more technically demanding and has higher complication rates than LSG [\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e]. Accordingly, a steep learning curve (LC) was generally required to meet its safety standards[\\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e]. As a result, only a handful of studies have addressed the learning process in a low-volume center [\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eTraditionally, surgical procedures were mostly learned through observation, on-the-spot assistance or field practice. As time progressed, new era of surgical education platforms emerged[\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e]. Online media resources are frequently used to facilitate and improve the learning process [\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e] and served as valuable method in our learning process. Starting with one-anastomosis gastric bypass (OAGB-MGB), we then modify our practice because arguments and controversies emerged such as the long-term consequences of bile reflux and nutrition problems [\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]. As practicing laparoscopic surgeons with 10\\u0026thinsp;+\\u0026thinsp;years of experience in various gastrointestinal surgeries and proficient in suturing techniques, we deemed we were ready to incorporate LRYGB as our treatment modality after attending education courses, dry lab training and conferences consisting of live demonstrations as well as applying our initial successive experience in performing OAGB-MGB[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]. Moreover, since Wittgrove \\u003cem\\u003eet al\\u003c/em\\u003e. first established LRYGB [\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e], several vital steps of the original technique have been modified. For example, the preferable placement of the Roux limb has changed from the retro-gastric/retro-colic [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e] to the ante-colic position. Common techniques utilized in gastrojejunostomy have shifted from circular-stapled [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] to linear-stapled anastomosis or a total hand sewn technique. To address enterotomy defects, the method shifted from stapled closure [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] to perform a sutured closure to avoid stenosis. There is a tendency to routinely closure of mesentery defects; however, in the past, some choose to left open for technical reasons [\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eThe aim of this study was to reappraise the learning curve of LRYGB under the aforementioned modern background in a low-volume unit. Our primary goal was to verify its safety according to the proficiency of medical staff, with a focus on 30-day per-operative outcomes.\\u003c/p\\u003e \"},{\"header\":\"Methods\",\"content\":\"\\u003cp\\u003eFrom January 2016 to December 2019, all data of consecutive patients who underwent primary LRYGB under the care of a single surgeon were collected retrospectively from a prospectively maintained database after obtaining institutional review board approval. Patients were eligible for inclusion if they met the regional criteria proposed by the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) [\\u003ca href=\\\"#_ENREF_17\\\"\\u003e17\\u003c/a\\u003e]. There are no specific selection criteria except a body mass index (BMI) \\u0026gt;50 kg/m\\u003csup\\u003e2\\u003c/sup\\u003e, as gastric bypass is generally less effective in these patients [\\u003ca href=\\\"#_ENREF_18\\\"\\u003e18\\u003c/a\\u003e]\\u003csup\\u003e,\\u003c/sup\\u003e and they have a higher rate of complications than patients with a lower BMI [\\u003ca href=\\\"#_ENREF_19\\\"\\u003e19\\u003c/a\\u003e]. Nevertheless, the final decision was made using a shared decision-making process after fully considering the benefits, risks and potential long-term outcomes of each procedure.\\u003c/p\\u003e\\n\\u003cp\\u003eTo assess the learning process, patients were divided into three groups based on their surgery time and case distributions: group A included initial patients who underwent primary LRYGB during 2016-17. Groups B and C included patients who underwent surgery during 2018 and 2019, respectively. All patients underwent complete preoperative evaluations. The recorded parameters included patient demographic factors and anthropometric data as well as all relevant outcome measures, including the operation time, length of stay (LOS) and 30-day complications, such as emergency room (ER) visit, readmission, reoperation and conversion.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eSurgical technique\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eLRYGB was performed with a four-abdominal trocar technique and a Nathanson liver retractor. This surgical technique utilized a linear stapler to create a lesser curve-based, 30-ml vertical gastric pouch over a 32 Fr. calibrating tube with 100-cm ante-colic, ante-gastric Roux limb and 100-cm biliopancreatic limb. The enterotomies for both anastomoses were hand-sewn closed. Both mesenteric defects were routinely closed with nonabsorbable sutures.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eData collection and statistical analysis\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe Statistical Package for the Social Sciences software version 20.0 (SPSS Inc., Chicago, Illinois, USA) was used to perform the statistical analyses. Descriptive results regarding continuous variables are presented as the means \\u0026plusmn; standard deviations, and categorical variables are presented as counts and percentages. Data were analyzed using Fisher\\u0026rsquo;s exact test for categorical data, and the unpaired t test was used for parametric data when appropriate. Tests for statistical significance were two-sided, with a level of significance of 0.05.\\u003c/p\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eFrom January 2016 to December 2019, a total of two hundred and four patients underwent bariatric or metabolic procedures in our unit. Among them, three patients underwent a nonprimary procedure, five patients underwent LSG, and 39 patients underwent OAGB-MGB during 2016-17. In 2018, two patients underwent a nonprimary procedure; two patients underwent LSG, and 18 patients underwent OAGB-MGB. In 2019, six patients underwent a nonprimary procedure; one patient underwent LSG, and 20 patients underwent OAGB-MGB. All the patients who did not fulfill the inclusion criteria were excluded from the analysis, leaving one hundred and eight patients enrolled in this study. Of these, 36 patients who underwent primary LRYGB during 2016-17 were assigned to group A. The other 38 and 34 patients who underwent primary LRYGB in 2018 and 2019 were assigned to group B and group C, respectively.\\u003c/p\\u003e\\n\\u003cp\\u003eThe demographic details and clinical characteristics are outlined in Table 1. There were no significant differences between group B and group A with respect to age, sex, preoperative weight or incidence of common comorbidities. However, patients in group B had a significantly lower BMI (35.1 \\u0026plusmn; 3.8 kg/m\\u003csup\\u003e2\\u003c/sup\\u003e vs. 37.0\\u0026plusmn; 3.6 kg/m\\u003csup\\u003e2\\u003c/sup\\u003e; p=0.03) and had a higher rate of hypertension (HTN) (44.7% vs. 22.8%; p=0.04) than those in group A. Group C was not different in terms of age, female proportion, or baseline BMI than group B, but group C had a tendency toward a higher rate of diabetes mellitus (32.4% vs. 21.1%; p=0.28) and a lower rate of HTN (35.3% vs. 44.7%; p=0.41) than group B.\\u003c/p\\u003e\\n\\u003cp\\u003eThe surgical characteristics and outcomes are listed in Table 2. As shown, only one concomitant procedure, partial gastrectomy for benign lesions, was carried out in group A. The mean operation time was significantly decreased in group B compared to group A (96.1 min vs. 114.9 min, respectively; p\\u0026lt;0.001) and was similar between group B and group C (96.1 min vs. 92.1 min; p=0.20). The mean LOS was also markedly shortened in group B compared to that in group A (2.2 \\u0026plusmn; 0.5 days vs. 2.9 \\u0026plusmn; 0.8 days; p \\u0026lt; 0.001) and was similar, at 2.2 days, between group C and group B (p=0.70). All procedures were complete with a laparoscopic approach without open conversion. The rate of 30-day complications was not different between groups B and A (2.6% vs. 2.8%; p= 0.97) or between groups C and B (2.9% vs. 2.6%; p=0.62).\\u003c/p\\u003e\\n\\u003cp\\u003eA total of five patients experienced 30-day adverse events and three of them were classified as with complications. One patient in group A was readmitted for gastrojejunostomy stenosis on postoperative day (POD) 30, which was relieved under a single session of balloon dilatation. In group B, two patients visited the ER after discharge; one visited for nonspecific focal abdominal pain. Another patient with hematemesis on POD 9 was readmitted and recovered uneventfully after proper medical treatment. In group C, one patient was noted to have self-limiting melena that subsided under supportive treatment. Another patient visited the ER for lower back pain. The rates of 30-day ER visits and 30-day readmission were not different between the groups. There was no reported anastomotic leakage, reoperation or mortality throughout the study period.\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\" \\u003cp\\u003eHerein, we reported the outcomes of initial 108 patients who underwent LRYGB over a 4-yr period in a low-volume hospital, indicating LC. Comparing the results among the 3 groups; significant improvements in the operation time and LOS with an acceptably low rate of complications was observed after the initial 36 cases (group A). The present study demonstrated that the LC of LRYGB can be safely reduced to 30\\u0026thinsp;+\\u0026thinsp;cases in the modern era under a unique setting.\\u003c/p\\u003e \\u003cp\\u003eBecause of increasingly complex techniques and the dependence on advanced instruments, the acquisition of new laparoscopic skills is considered to be difficult. When conducting LRYGB in morbidly obese patients, there are likely several other inherent technical barriers, such as body habitus, multistep reconstructive procedures that involve multi-abdominal quadrants and laparoscopic suturing and knot tying skills. Therefore, it was once rated as a 9.5 on a difficulty scale of 10, indicating substantial technical difficulty[\\u003cspan citationid=\\\"CR20\\\" class=\\\"CitationRef\\\"\\u003e20\\u003c/span\\u003e]. These skill-related prerequisites can result in adverse consequences in the early phase of practice, especially in a low-volume practice [\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e]. Traditionally, various educational programs, such as workshops[\\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e21\\u003c/span\\u003e], bariatric fellowships[\\u003cspan citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e22\\u003c/span\\u003e] and systematic training programs[\\u003cspan citationid=\\\"CR23\\\" class=\\\"CitationRef\\\"\\u003e23\\u003c/span\\u003e], have been available to facilitate this process. In recent years, new-era platforms have emerged, providing another kind of auxiliary training approach[\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e]. Their popularity among medical professionals has been increasing, as they generally enable more visual and auditory interactions than journals or text books [\\u003cspan citationid=\\\"CR24\\\" class=\\\"CitationRef\\\"\\u003e24\\u003c/span\\u003e]. A systematic review for the impact of e-learning demonstrates significant gains in knowledge compared with traditional teaching patterns [\\u003cspan citationid=\\\"CR25\\\" class=\\\"CitationRef\\\"\\u003e25\\u003c/span\\u003e]. In our self-learning process, apart from traditional learning methods, these online multimedia materials provide considerable references and guidance despite the lack of objective tools for gauging their impact.\\u003c/p\\u003e \\u003cp\\u003eConsidering a single surgeon\\u0026rsquo;s perspective, we retrieved comparative data in the literature discussing the relevant process by a single surgeon (Table\\u0026nbsp;3). Among them, variability in surgical techniques exists. Moreover, several modifications of traditional methods have occurred, such as retro-colic placement of the Roux limb [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e] or a circular-stapled anastomosis [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] had largely been fall out of favor. Meanwhile, there are differences among studies in terms of backgrounds, annual hospital volumes or former laparoscopic/bariatric experience levels. Though with undisputable importance and heightened awareness for proper fellowship training [\\u003cspan citationid=\\\"CR26\\\" class=\\\"CitationRef\\\"\\u003e26\\u003c/span\\u003e], there is no standard approach of teaching provided and accredited bariatric programs are not globally available. For example, while carried out during different periods, some hospitals conduct other laparoscopic bariatric procedures [\\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR28\\\" class=\\\"CitationRef\\\"\\u003e28\\u003c/span\\u003e] or perform open bariatric surgeries beforehand [\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e], others just started after complete with fellowship training [\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e] or are based solely on advanced laparoscopic skills [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e]. Additionally, there were with considerably different case selection criteria. In general, fellowship trained bariatric surgeons or those conduct after preceding bariatric experience appears to have a shorter LC and implement a more efficient practice. For instance, after completing a month-long mini-fellowship, Shen \\u003cem\\u003eet al\\u003c/em\\u003e. achieved a considerably decreased complication rate and proficiency after only 30 cases [\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e]. In particular, they utilized the case selection criteria following IFSO Asian-Pacific guidelines, similar to our research [\\u003cspan citationid=\\\"CR17\\\" class=\\\"CitationRef\\\"\\u003e17\\u003c/span\\u003e]. However, they reported an initial complication rate of 26.7%, which included a 6.7% conversion, 10% reoperation and 5% leakage rate. While surgeons at high-volume hospitals often have the opportunity to master the procedure in a short period of time with preferable results [\\u003cspan citationid=\\\"CR30\\\" class=\\\"CitationRef\\\"\\u003e30\\u003c/span\\u003e], Shin \\u003cem\\u003eet al\\u003c/em\\u003e. participated as assistants in 30 surgeries and conducted the first few surgeries under proctoring. They analyzed their first one hundred cases within 5 months and concluded that the LC plateaued after 50 surgeries [\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]. While they realize with marked decreasing operation times (113\\u0026nbsp;min pre-LC and 73\\u0026nbsp;min post-LC), they indicated that there was no further notable reduction in complications after the LC. With particularly vast prior experience in LAP BAND \\u0026reg;, Ballesta-Lopez \\u003cem\\u003eet al\\u003c/em\\u003e. also published a large series with marked decreased operative time and LOS after the first 100 surgeries[\\u003cspan citationid=\\\"CR28\\\" class=\\\"CitationRef\\\"\\u003e28\\u003c/span\\u003e]. Particularly, as one of only two studies, in addition to that by Andrew \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e], which were conducted with totally hand-sewn gastrojejunostomy, they reported a no negligible leakage rate of up to 9%, a 5.1% reoperation rate (mostly for leakage) and a 29.2% complication rate. In other studies with only prior advanced laparoscopic experience [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e], the LC took slightly longer, and there was a substantially prolonged operation time compared with studies involving surgeons who completed a fellowship [\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e]. For instance, Oliak \\u003cem\\u003eet al\\u003c/em\\u003e. reported a series with the highest mean BMI of 51\\u0026nbsp;kg/m\\u003csup\\u003e2\\u003c/sup\\u003e and proposed that the LC plateaued after 75 surgeries[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e]. Surgeons\\u0026rsquo; operative times decreased substantially from 189\\u0026nbsp;min during the first 75 cases and then decreased gradually. Notably, the perioperative complication rates were substantial among all studies both before (32%) and after LC (15%). Nguyen \\u003cem\\u003eet al\\u003c/em\\u003e. evaluated 150 consecutive cases, with the longest mean operation time of 250\\u0026nbsp;min before LC; they too observed that an initial lack of experience (\\u0026lt;\\u0026thinsp;75 cases) was a major factor associated with major complications and an increased reoperation rate [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]. On the other hand, with advanced laparoscopic skills and preemptive bariatric experience; Agrawal \\u003cem\\u003eet al\\u003c/em\\u003e. suggest that LRYGB can be performed safely with minimal complications of only 1.4% and effectively without any LC required[\\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e]. It is noticeable that our initial result stabilized after just 36 surgeries and we had a low initial 30-day complication rate of 2.8%. Only the difference is their research was after completion of fellowship training[\\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e]. However, concordant with these forenamed studies, a sharp improvement in terms of operation time was observed in current study after LC. As findings of Shin \\u003cem\\u003eet al.\\u003c/em\\u003e[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e], we observed no further decrease in the complication rate after LC. Only one patient presented with stenosis, and two other patients presented with hemorrhagic complications: one with hematemesis and one with melena. Considering the reported stenosis rate between 2.2% and 10% [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e] and the hemorrhagic complication rate ranges from 1\\u0026ndash;3.3% during the learning process [\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e], we deemed our initial results to be acceptable. Furthermore, there was no mortality, leakage, conversion or other major complications. While prolonged hospital stay is not uncommon after such a procedure. Nguyen \\u003cem\\u003eet al\\u003c/em\\u003e. noted that 11% of their cases had LOS over 4 days [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]\\u003csup\\u003e,\\u003c/sup\\u003e and the LOS is reported to range between 6 to 6.4 days before the LC and 4.8 to 5 days after the LC[\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e]. We observed a notably shorter LOS, with a mean of 2.9 days before the LC and 2.2 days thereafter. In addition, only 2.8% of our patients required hospitalization for more than 3 days. Our LC and timespan to reach competency are in line with findings from a systemic review that reported between 30\\u0026ndash;70 surgeries [\\u003cspan citationid=\\\"CR31\\\" class=\\\"CitationRef\\\"\\u003e31\\u003c/span\\u003e]. It is worth mention that the consistent outcome obtained in group B and group C can be considered an early achievement of proficiency because we reached this goal within less than 70 accumulative surgeries, while historically, it usually takes between 70\\u0026ndash;150 surgeries[\\u003cspan citationid=\\\"CR31\\\" class=\\\"CitationRef\\\"\\u003e31\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eThere are likely many factors contributing to our early desirable results. First, in contrast to most studies with an unselective patient approach [\\u003cspan additionalcitationids=\\\"CR14\\\" citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR28\\\" class=\\\"CitationRef\\\"\\u003e28\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e], patients with a BMI\\u0026thinsp;\\u0026gt;\\u0026thinsp;50 were preferably offered alternative treatment modalities considering safety and long-term effectiveness [\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR32\\\" class=\\\"CitationRef\\\"\\u003e32\\u003c/span\\u003e]. As a result of this selective approach, the mean BMI of 36.1\\u0026nbsp;kg/m\\u003csup\\u003e2\\u003c/sup\\u003e in our series was significantly lower than former studies, which ranged from 43 to 51\\u0026nbsp;kg/m\\u003csup\\u003e2\\u003c/sup\\u003e [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e]. Second, as guidelines regarding tailored per-operative care were established in 2016 [\\u003cspan citationid=\\\"CR33\\\" class=\\\"CitationRef\\\"\\u003e33\\u003c/span\\u003e], a pragmatic enhanced recovery protocol was gradually adopted in our unit ever since. Furthermore, our preceding experience in OAGB-MGB may transferred to subsequent LRYGB and increase its safety [\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]. Likewise, comprehensive care and improved techniques have been demonstrated in other studies across different periods [\\u003cspan citationid=\\\"CR34\\\" class=\\\"CitationRef\\\"\\u003e34\\u003c/span\\u003e]. Because only two aforementioned studies included cases after 2010[\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e], we believe that general improvements further contribute to this desirable result.\\u003c/p\\u003e \"},{\"header\":\"Limitations\",\"content\":\" \\u003cp\\u003eLimited by the selective approach, our result may not be generalizable for all patient subgroups. Nevertheless, a desirable outcome can be accomplished during the learning process via this selective approach. Moreover, because of its retrospective design and nonrandomized nature, the presence of clinical heterogeneity between groups may compromise its comparativeness.\\u003c/p\\u003e \"},{\"header\":\"Conclusion\",\"content\":\" \\u003cp\\u003eIn conclusion, a gradual LC for LRYGB with acceptably low complication rate, shortened operation time and LOS can be achieved in unique settings. Additional data regarding long-term efficacy, safety and generalizability are required.\\u003c/p\\u003e \"},{\"header\":\"List of Abbreviations\",\"content\":\"\\u003cp\\u003eLRYGB, Laparoscopic Roux-en Y gastric bypass; BMI, body mass index;\\u003c/p\\u003e \\u003cp\\u003eLOS, length of stay; LSG, laparoscopic sleeve gastrectomy; LC, learning curve;\\u003c/p\\u003e \\u003cp\\u003eOAGB-MGB, one-anastomosis gastric bypass;\\u003c/p\\u003e \\u003cp\\u003eIFSO, International Federation for the Surgery of Obesity and Metabolic Disorders;\\u003c/p\\u003e \\u003cp\\u003eER, emergency room; HTN, hypertension; POD, postoperative day;\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eEthical approval \\u003c/strong\\u003e\\u003cstrong\\u003eand consent to participate\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAll procedures performed in studies involving human participants were in accordance with the ethical standards of institutional and/or national research committees and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. The research project was approved by local Institutional Review Board. Informed consent was waived because no data regarding the cases were disclosed.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eWritten informed consent for publication was waived because no clinical details and/or clinical images regarding the cases were disclosed.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and materials\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe datasets generated during and/or analyzed during the current study are not publicly available due\\u0026nbsp;to restrictions from local Institutional Review Board but are available from the corresponding author on reasonable request and with permission from the local Institutional Review Board.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting interests\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe authors declare that they have no competing interests\\u003cstrong\\u003e.\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe study was not sponsored and funded by any funding.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors' contributions\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eHung-Chieh Lo designed the study, performed the surgical procedures, followed the patients, and participated in the data analysis and writing of the manuscript. Sheng-Mao Wu contributed to the data analysis. All authors have read and approved the final version to be published.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgments \\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003e\\u003cstrong\\u003eObesity and overweight \\u003c/strong\\u003e[\\u003ca href=\\\"https://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight\\\"\\u003ehttps://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight\\u003c/a\\u003e]\\u003c/li\\u003e\\n\\u003cli\\u003eSj\\u0026ouml;str\\u0026ouml;m L, Lindroos AK, Peltonen M, Torgerson J, Bouchard C, Carlsson B, Dahlgren S, Larsson B, Narbro K, Sj\\u0026ouml;str\\u0026ouml;m CD\\u003cem\\u003e et al\\u003c/em\\u003e: \\u003cstrong\\u003eLifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery\\u003c/strong\\u003e. \\u003cem\\u003eN Engl J Med \\u003c/em\\u003e2004, 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\\u003c/em\\u003e2005, \\u003cstrong\\u003e19\\u003c/strong\\u003e(4):519-524.\\u003c/li\\u003e\\n\\u003cli\\u003eHuang CK, Lee YC, Hung CM, Chen YS, Tai CM: \\u003cstrong\\u003eLaparoscopic Roux-en-Y gastric bypass for morbidly obese Chinese patients: learning curve, advocacy and complications\\u003c/strong\\u003e. \\u003cem\\u003eObes Surg \\u003c/em\\u003e2008, \\u003cstrong\\u003e18\\u003c/strong\\u003e(7):776-781.\\u003c/li\\u003e\\n\\u003cli\\u003eShikora SA, Kim JJ, Tarnoff ME, Raskin E, Shore R: \\u003cstrong\\u003eLaparoscopic Roux-en-Y gastric bypass: results and learning curve of a high-volume academic program\\u003c/strong\\u003e. \\u003cem\\u003eArch Surg \\u003c/em\\u003e2005, \\u003cstrong\\u003e140\\u003c/strong\\u003e(4):362-367.\\u003c/li\\u003e\\n\\u003cli\\u003eWehrtmann FS, de la Garza JR, Kowalewski KF, Schmidt MW, M\\u0026uuml;ller K, Tapking C, Probst P, Diener MK, Fischer L, M\\u0026uuml;ller-Stich BP\\u003cem\\u003e et al\\u003c/em\\u003e: \\u003cstrong\\u003eLearning Curves of Laparoscopic Roux-en-Y Gastric Bypass and Sleeve Gastrectomy in Bariatric Surgery: a Systematic Review and Introduction of a Standardization\\u003c/strong\\u003e. \\u003cem\\u003eObes Surg \\u003c/em\\u003e2020, \\u003cstrong\\u003e30\\u003c/strong\\u003e(2):640-656.\\u003c/li\\u003e\\n\\u003cli\\u003eParmar CD, Bryant C, Luque-de-Leon E, Peraglie C, Prasad A, Rheinwalt K, Musella M: \\u003cstrong\\u003eOne Anastomosis Gastric Bypass in Morbidly Obese Patients with BMI \\u0026ge;\\u0026thinsp;50\\u0026nbsp;kg/m(2): a Systematic Review Comparing It with Roux-En-Y Gastric Bypass and Sleeve Gastrectomy\\u003c/strong\\u003e. \\u003cem\\u003eObes Surg \\u003c/em\\u003e2019, \\u003cstrong\\u003e29\\u003c/strong\\u003e(9):3039-3046.\\u003c/li\\u003e\\n\\u003cli\\u003eThorell A, MacCormick AD, Awad S, Reynolds N, Roulin D, Demartines N, Vignaud M, Alvarez A, Singh PM, Lobo DN: \\u003cstrong\\u003eGuidelines for Perioperative Care in Bariatric Surgery: Enhanced Recovery After Surgery (ERAS) Society Recommendations\\u003c/strong\\u003e. \\u003cem\\u003eWorld J Surg \\u003c/em\\u003e2016, \\u003cstrong\\u003e40\\u003c/strong\\u003e(9):2065-2083.\\u003c/li\\u003e\\n\\u003cli\\u003eLee WJ, Almalki OM, Ser KH, Chen JC, Lee YC: \\u003cstrong\\u003eRandomized Controlled Trial of One Anastomosis Gastric Bypass Versus Roux-En-Y Gastric Bypass for Obesity: Comparison of the YOMEGA and Taiwan Studies\\u003c/strong\\u003e. \\u003cem\\u003eObes Surg \\u003c/em\\u003e2019, \\u003cstrong\\u003e29\\u003c/strong\\u003e(9):3047-3053.\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"},{\"header\":\"Tables\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eTable 1. Demographic and clinical characteristics of the patients, mean (SD)\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003eGroup A\\u003c/p\\u003e\\n\\u003cp\\u003e(N=36)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003eGroup B\\u003c/p\\u003e\\n\\u003cp\\u003e(N=38)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003eGroup\\u003c/p\\u003e\\n\\u003cp\\u003eA vs. B\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp; p-value\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;Group C\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;(N=34)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003eGroup\\u003c/p\\u003e\\n\\u003cp\\u003eB vs. C\\u003c/p\\u003e\\n\\u003cp\\u003ep-value\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eAge (years)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e35.3 \\u0026plusmn;10.3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e38.5 \\u0026plusmn; 9.1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;0.16\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e39.6 \\u0026plusmn; 9.2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp; 0.62\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eSex, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"3\\\" width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e14 (38.9)\\u003c/p\\u003e\\n\\u003cp\\u003e22 (61.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"3\\\" width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e15 (39.5)\\u003c/p\\u003e\\n\\u003cp\\u003e23 (60.5)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"3\\\" width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e15 (44.1)\\u003c/p\\u003e\\n\\u003cp\\u003e19 (55.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"3\\\" width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e0.69\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eMale\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e0.96\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eFemale\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003ePreoperative weight (kg)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e102.8 \\u0026plusmn; 16.7\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e95.8 \\u0026plusmn; 17.1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp; 0.08\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e98.7 \\u0026plusmn; 16.0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 0.44\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eBMI (kg/m\\u003csup\\u003e2\\u003c/sup\\u003e)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e37.0 \\u0026plusmn; 3.6\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e35.1 \\u0026plusmn; 3.8\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.03\\u003csup\\u003e✽\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e36.3 \\u0026plusmn; 3.2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.13\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"6\\\" width=\\\"652\\\"\\u003e\\n\\u003cp\\u003eComorbidities, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eDiabetes mellitus\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e10 (27.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e8 (21.1)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e11 (32.4)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.28\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eHypertension\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e8 (22.2)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e17 (44.7)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.04\\u003csup\\u003e✽\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;12 (35.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.41\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"178\\\"\\u003e\\n\\u003cp\\u003eDyslipidemia\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"101\\\"\\u003e\\n\\u003cp\\u003e18 (50)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e21 (55.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"89\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.65\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"94\\\"\\u003e\\n\\u003cp\\u003e18 (52.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"95\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.84\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"6\\\" width=\\\"652\\\"\\u003e\\n\\u003cp\\u003eBMI, Body mass index\\u003c/p\\u003e\\n\\u003cp\\u003eData are expressed as the means \\u0026plusmn; standard deviations or as numbers and percentages\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eTable 2. Surgical perspectives and outcomes, mean (SD)\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;Group A\\u003c/p\\u003e\\n\\u003cp\\u003e(N=36)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;Group B\\u003c/p\\u003e\\n\\u003cp\\u003e(N=38)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003eGroup\\u003c/p\\u003e\\n\\u003cp\\u003eA vs. B\\u003c/p\\u003e\\n\\u003cp\\u003ep-value\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;Group C\\u003c/p\\u003e\\n\\u003cp\\u003e(N=34)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003eGroup\\u003c/p\\u003e\\n\\u003cp\\u003eB vs. C\\u003c/p\\u003e\\n\\u003cp\\u003ep-value\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eConcomitant procedure,\\u003c/p\\u003e\\n\\u003cp\\u003en (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e1(2.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e0.30\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eOp time (min)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e114.9 \\u0026plusmn; 29.1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e96.1 \\u0026plusmn; 13.5\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026lt; 0.001\\u003csup\\u003e✽\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e92.1 \\u0026plusmn; 12.1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e0.20\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eLOS (days)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e2.9 \\u0026plusmn; 0.8\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e2.2 \\u0026plusmn; 0.5\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u0026lt; 0.001\\u003csup\\u003e✽\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e2.2 \\u0026plusmn; 0.4\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 0.70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eConversion\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003e30-day complications, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e1 (2.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1 (2.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp; 0.97\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1 (2.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u0026nbsp;\\u0026nbsp; 0.62\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eStenosis\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eMelena\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003eHematemesis\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003e30-day ER visit, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e2 (5.3)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e0.16\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1 (2.9)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e0.62\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003e30-day Readmission, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e1 (2.8)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e1 (2.6)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e0.97\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e0.34\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"30%\\\"\\u003e\\n\\u003cp\\u003e30-day Mortality, n (%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"13%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003e0\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"6\\\" width=\\\"100%\\\"\\u003e\\n\\u003cp\\u003eOp, Operation; LOS, Length of stay; ER, Emergency room\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cbr /\\u003eTable 3. List of historical studies involving a single surgeon\\u003c/strong\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\"\\u003e\\n\\u003ctbody\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" rowspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eAuthors\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"2\\\" width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003eStudy period\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"2\\\" width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eBackground\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"2\\\" width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003ePatients (n)\\u003c/p\\u003e\\n\\u003cp\\u003eGroups\\u003c/p\\u003e\\n\\u003cp\\u003einclusion criteria\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"2\\\" width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003eAge\\u003csup\\u003ea\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e(years)/\\u003c/p\\u003e\\n\\u003cp\\u003eBMI\\u003csup\\u003ea\\u003c/sup\\u003e (kg/m\\u003csup\\u003e2\\u003c/sup\\u003e)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd rowspan=\\\"2\\\" width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003eLC\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003eMean Op time (min)\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"14%\\\"\\u003e\\n\\u003cp\\u003eComplications\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp;(%)\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003ePre- LC\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003ePost- LC\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003ePre-\\u003c/p\\u003e\\n\\u003cp\\u003eLC\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003ePost-\\u003c/p\\u003e\\n\\u003cp\\u003eLC\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eAgrawal \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_27\\\"\\u003e27\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e10-11\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003cp\\u003efellowship\\u003c/p\\u003e\\n\\u003cp\\u003elaparoscope bariatric\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e74\\u003c/p\\u003e\\n\\u003cp\\u003e1 group\\u003c/p\\u003e\\n\\u003cp\\u003eprimary procedures\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e45.1\\u003c/p\\u003e\\n\\u003cp\\u003e47.7\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003eNot\\u003c/p\\u003e\\n\\u003cp\\u003erequired\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e160\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003en/a\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e1.4\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003en/a\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eShen \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_16\\\"\\u003e16\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e09-11\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003cp\\u003efellowship\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e60\\u003c/p\\u003e\\n\\u003cp\\u003e2 groups\\u003c/p\\u003e\\n\\u003cp\\u003eIFSO-APCcriteria\\u003csup\\u003eb\\u003c/sup\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e34.2\\u003c/p\\u003e\\n\\u003cp\\u003e41.5\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e30\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e120\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e80\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e26.7\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e6.7\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eShin \\u003cem\\u003eet al\\u003c/em\\u003e.\\u003c/p\\u003e\\n\\u003cp\\u003e[\\u003ca href=\\\"#_ENREF_14\\\"\\u003e14\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e03\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003cp\\u003efellowship\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e100\\u003c/p\\u003e\\n\\u003cp\\u003e2 groups\\u003c/p\\u003e\\n\\u003cp\\u003eunselective\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e42.6\\u003c/p\\u003e\\n\\u003cp\\u003e47.6\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e113\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e73\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e32\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e\\u0026nbsp;\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e8\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eOliak \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_12\\\"\\u003e12\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e99-01\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e225\\u003c/p\\u003e\\n\\u003cp\\u003e3 groups\\u003c/p\\u003e\\n\\u003cp\\u003eprimary procedures\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e40\\u003c/p\\u003e\\n\\u003cp\\u003e51\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e75\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e189\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e125\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e32\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e15\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eHuang \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_29\\\"\\u003e29\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e05-07\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e100\\u003c/p\\u003e\\n\\u003cp\\u003e2 groups\\u003c/p\\u003e\\n\\u003cp\\u003eunselective\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e31.2\\u003c/p\\u003e\\n\\u003cp\\u003e43\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e50\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e217\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e105\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e15\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e3\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eNguyen \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_15\\\"\\u003e15\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003en/a\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e150\\u003c/p\\u003e\\n\\u003cp\\u003e2 groups\\u003c/p\\u003e\\n\\u003cp\\u003eunselective\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e40\\u003c/p\\u003e\\n\\u003cp\\u003e47\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e75\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e250\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003en/a\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e12\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eAndrew \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_13\\\"\\u003e13\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e02-04\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eOpen bariatric\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e201\\u003c/p\\u003e\\n\\u003cp\\u003e3 groups\\u003c/p\\u003e\\n\\u003cp\\u003eunselective\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e37\\u003c/p\\u003e\\n\\u003cp\\u003e49.2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e70\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e145\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e118\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e19.4\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e11.9\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eBallesta-Lopez \\u003cem\\u003eet al\\u003c/em\\u003e. [\\u003ca href=\\\"#_ENREF_28\\\"\\u003e28\\u003c/a\\u003e]\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e00-04\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003cp\\u003eLAP BAND\\u0026reg;\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e600\\u003c/p\\u003e\\n\\u003cp\\u003e6 groups\\u003c/p\\u003e\\n\\u003cp\\u003eunselective\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e38.7\\u003c/p\\u003e\\n\\u003cp\\u003e44.4\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e100\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e166\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e109\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e29.2\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e14\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003ctr\\u003e\\n\\u003ctd colspan=\\\"2\\\" width=\\\"15%\\\"\\u003e\\n\\u003cp\\u003eCurrent study\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e16-19\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003eAdvanced scope\\u003c/p\\u003e\\n\\u003cp\\u003elaparoscope bariatric\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"12%\\\"\\u003e\\n\\u003cp\\u003e108\\u003c/p\\u003e\\n\\u003cp\\u003e3 groups\\u003c/p\\u003e\\n\\u003cp\\u003eprimary procedures\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"11%\\\"\\u003e\\n\\u003cp\\u003e37.8\\u003c/p\\u003e\\n\\u003cp\\u003e36.1\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"9%\\\"\\u003e\\n\\u003cp\\u003e30+\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"8%\\\"\\u003e\\n\\u003cp\\u003e115\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"6%\\\"\\u003e\\n\\u003cp\\u003e96\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e2.8\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003ctd width=\\\"7%\\\"\\u003e\\n\\u003cp\\u003e2.6\\u003c/p\\u003e\\n\\u003c/td\\u003e\\n\\u003c/tr\\u003e\\n\\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eLC, Learning curve; Op, Operation; BMI, Body mass index; n/a, No data available\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003csup\\u003ea \\u003c/sup\\u003eMean\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003csup\\u003eb\\u003c/sup\\u003e IFSO-APC\\u0026nbsp;criteria stands for International Federation for the Surgery of Obesity and Metabolic Disorders Asia Pacific Chapter criteria [\\u003ca href=\\\"#_ENREF_17\\\"\\u003e17\\u003c/a\\u003e]\\u003c/p\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-surgery\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"bsur\",\"sideBox\":\"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/bsur/default.aspx\",\"title\":\"BMC Surgery\",\"twitterHandle\":\"@BMC_series\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Obesity, Roux-en Y Gastric Bypass, Bariatric, Learning curve\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-103556/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-103556/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cstrong\\u003eBackground \\u003c/strong\\u003eThe study aim was to reevaluate the learning curve of laparoscopic Roux-en Y gastric bypass (LRYGB) in the modern era considering a single surgeon’s experience.\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eMethods \\u003c/strong\\u003eExcept those with body mass index (BMI) \\u0026gt;50 kg/m\\u003csup\\u003e2 \\u003c/sup\\u003eneeds further discussion;\\u003csup\\u003e \\u003c/sup\\u003eall other patients who met the regional criteria and underwent primary LRYGB were retrospectively enrolled. Those who underwent surgery in 2016-17, 2018 and 2019 by a single surgeon with 10+ years of laparoscopic experience were assigned to groups A, B and C, respectively. Patient demographics and 30-day outcome data, including operation time, length of stay (LOS), emergency room visits, readmission, and reoperation, were compared between groups.\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eResults \\u003c/strong\\u003eOne hundred and eight patients met the inclusion criteria; 36, 38, and 34 patients were assigned to groups A, B and C, respectively. There were no differences in age, sex distribution or common comorbidities between groups, except group B had a lower BMI (35.1 kg/m\\u003csup\\u003e2 \\u003c/sup\\u003evs. 37.0 kg/m\\u003csup\\u003e2\\u003c/sup\\u003e) and a higher rate of hypertension (44.7% vs. 22.2%) than group A. The operation time was markedly reduced (96.1 min and 114.9 min, respectively), and the LOS was shortened (2.2 days and 2.9 days, respectively) in group B compared to group A and remained stationary in group C, with no further reduction in 30-day complications.\\u003c/p\\u003e\\u003cp\\u003e\\u003cstrong\\u003eConclusion \\u003c/strong\\u003eThe learning process for LRYGB\\u0026nbsp;can be shortened to approximately 30 cases if conducted selectively and by experienced laparoscopic surgeons. Further follow-up is required to verify the long-term safety and its applicability to other patient subgroups.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Re-Appraisal Learning Curve of Laparoscopic Roux-En Y Gastric Bypass: Results of One Hundred and Eight Cases From A Low Volume Unit\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2020-11-12 15:29:56\",\"doi\":\"10.21203/rs.3.rs-103556/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Minor revision\",\"date\":\"2020-12-16T00:00:00+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2020-12-15T00:00:00+00:00\",\"index\":1,\"fulltext\":\"Recommendation: Accept after minor essential revisions\\nForm responses:\\n---\\n\\nComments to Author:\\n---\\nI read with interest the manuscript \\\"Re-appraisal Learning curve of Laparoscopic Roux-en Y Gastric Bypass: results of one hundred and eight cases from a low volume unit\\\" by Hung-Chieh Lo, and Sheng-Mao Wu.\\nI was pleased to examine their results: the mainstream literature is often focused on \\\"centers of excellence\\\" and \\\"high-volume centers\\\", disregarding the experience of lower volume centers, and even questioning their results. The authors should be complimented for sharing their excellent results.\\n\\nPlease, let me address a few issues with the manuscript. I believe that addressing them would enhance the value of the study.\\n\\n1. General issues: the language is overall correct; however, in several instances it could be improved as far as use of verb tenses (it appears to me that the present simple was used instead of the past tense in a few instances: just as an example \\\"we then modify\\\" in the \\\"background\\\" or tenses are mismatched as in \\\"Online media resources are frequently used ... and served\\\"), articles (a few are missing) and clarity. In addition I would avoid the use of non-necessary abbreviations: \\\"learning curve\\\" really does not need to be abbreviated, and even POD (although common) is used just once in the manuscript and is unnecessary.\\n\\n2. Background:\\na.it appears rather long. I am not sure that the part between lines 74-79 (\\\"As practicing...OAGB-MGB\\\") is necessary; certainly, the subsequent part (\\\"Moreover...reasons\\\") it is not, as it adds nothing to the background of the study.\\n\\nb. The introduction should better explain the rationale for the study (why is the study needed?), its purpose and the study outcomes, rather than the personal evolution of the authors and their surgery. About the study outcomes, I would like to stress that the authors state: \\\"The aim of this study was to reappraise the learning curve of LRYGB under the aforementioned modern background in a low-volume unit. Our primary goal was to verify its [does the possessive adjective refer to \\\"learning curve\\\"? \\\"unit\\\"? \\\"LRYGB\\\"? - see item 1] safety according to the proficiency of medical staff, with a focus on 30-day per-operative outcomes\\\"; however, the \\\"outcomes\\\" should be specified, and operative time, in the study, is at least as relevant as the 30-day outcomes, but not mentioned here.\\n\\nb. What do the authors exactly mean with \\\"LRYGB was the standard bariatric-metabolic procedure and was performed secondarily after laparoscopic sleeve gastrectomy\\\"? Maybe: \\\"LRYGB was the standard [most commonly adopted?] bariatric metabolic primary procedure, and was also performed secondarily after laparoscopic sleeve gastrectomy\\\"?\\n\\n3. Methods:\\na. A few very relevant items are missing from the \\\"methods section\\\"; the study design should be stated (retrospective cohort study), the institutional setting, the outcomes and a few more details should be stated and defined. Please refer to the STROCCS guideline and checklist for reporting surgical observational studies: it would be easier not to miss relevant items in this and other sections.\\n\\nb. \\\"There are no specific selection criteria except a body mass index (BMI) \\u003e50 kg/m2\\\". Did the authors mean \\\"exclusion criteria\\\"?\\n\\nc. In the Discussion the authors state: \\\"Second, as guidelines regarding tailored per-operative care were established in 2016 [33], a pragmatic enhanced recovery protocol was gradually adopted in our unit ever since.\\\". Some details of the protocol should be stated in the Methods, and changes in the protocol after 2016 should be detailed: did they introduce a preoperative weight loss program? Did they eliminate time consuming steps in the operation (for example nasogastric tube and drains have often been omitted by surgical teams during the learning curve, section of the greater omentum is routine by some teams, not by others). Those changes are part of the learning curve, still need to be detailed.\\n\\n4. Weight related results. I acknowledge that your follow-up is short; however, in bariatric surgery, complication rate has little sense, unless is matched with weight loss outcomes. Of course, the short follow-up will always be a limitation of the study; however, I believe that knowing that your excellent complication rate is matched to an acceptable (even if short term) weight loss would help.\\n\\n5. Conclusions. The conclusions appear generic. The study shows that a satisfactory learning curve can be safely accomplished in a low-volume center; also confirms that some parameters plateau after a learning curve of 30 bypasses; these appear to me interesting conclusions, while the meaning of \\\"unique setting\\\" is ambiguous.* Publons Reviewer Recognition. Springer Nature can send verification of this review directly to Publons (a subsidiary of Clarivate Analytics). If you would like to take advantage of this service, please click on the “Yes” option below. Your name, email address, title of the reviewed manuscript, name of the journal, and date of your review submission (the “Review Data”) will then be transmitted to Publons upon publication of the manuscript. If you have already registered at Publons, they will notify you of the receipt of this review and update your profile as per your settings and their policy. If you are not registered with Publons, you will receive an email from them asking you to register in order for them to be able to recognize your review on your new profile page. Publons may use the Review Data to generate derivative metadata for the benefit of Publons and you as a reviewer, carefully considering the sensitivity of such information. For example, Publons may verify your record as a reviewer by updating your profile published on its webservice if you have registered for such service or help editors to identify candidate reviewers. Please find the details of processing in Publons’ privacy policy https://publons.com/about/terms: **Yes**\\n* Declaration of competing interests: **I declare that I have no competing interests**\\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please publish my name with my report.**\\n* Is the study design appropriate to answer the research question (including the use of appropriate controls), and are the conclusions supported by the evidence presented?: **Yes**\\n* Are the methods sufficiently described to allow the study to be repeated?: **No**\\n* Is the use of statistics and treatment of uncertainties appropriate?: **Yes**\\n* Is the presentation of the work clear?: **Yes**\\n* Are the images in this manuscript (including electrophoretic gels and blots) free from apparent manipulation?: **Yes**\\n\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2020-12-09T00:00:00+00:00\",\"index\":2,\"fulltext\":\"Recommendation: Accept after minor essential revisions\\nForm responses:\\n---\\n\\nComments to Author:\\n---\\nThe data about a learning curve of a surgical technique are often interesting, especially when this experience concerns a low volume center. Your result seems to be encouraging in relation to other studies' one that you have mentioned.\\nThe heterogeneity of your sample represents a limit that should not be underestimated. It could be overcome with a perspective study. Despite you have considered relevant issues like age, BMI (avoiding BMI\\u003e 50kg/m2) and preoperative BMI, it could be at the same time interesting knowing the occurrence of previous surgery that could have impact on operative time.\\nIn the future, a remarkable feature could be evaluating your learning curve applied on other laparoscopic technique or other bariatric surgery.\\nDespite the different operative time between Group A and B, it is noteworthy that the rate of 30-day complications was similar between these two groups. In literature were there other work in which the complications are not associated to surgeon's experience?\\nI suggest you to review your English.\\nIn my opinion, although your short-term complication rate, the work is well-done and it focus on specific aspects as the various kind of approaches in the surgical training. A view on a longer follow up could be a good starting point for a new work, for example in relation to weight loss.\\n* Publons Reviewer Recognition. Springer Nature can send verification of this review directly to Publons (a subsidiary of Clarivate Analytics). If you would like to take advantage of this service, please click on the “Yes” option below. Your name, email address, title of the reviewed manuscript, name of the journal, and date of your review submission (the “Review Data”) will then be transmitted to Publons upon publication of the manuscript. If you have already registered at Publons, they will notify you of the receipt of this review and update your profile as per your settings and their policy. If you are not registered with Publons, you will receive an email from them asking you to register in order for them to be able to recognize your review on your new profile page. Publons may use the Review Data to generate derivative metadata for the benefit of Publons and you as a reviewer, carefully considering the sensitivity of such information. For example, Publons may verify your record as a reviewer by updating your profile published on its webservice if you have registered for such service or help editors to identify candidate reviewers. Please find the details of processing in Publons’ privacy policy https://publons.com/about/terms: **Yes**\\n* Declaration of competing interests: **I DECLARE THAT I HAVE NO COMPETING INTEREST**\\n* Reviewer Publication Consent. I agree for my report to be made available under an Open Access Creative Commons CC-BY License (http://creativecommons.org/licenses/by/4.0) if this manuscript is accepted for publication. Any comments that I do not wish to be included in the published report have been included as confidential comments to the editor, which will not be published.: **I agree to the terms of the CC-BY 4.0 license; please do not publish my name with my report. 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