Feasibility and Safety of Ambulatory Bariatric Surgery in a High-Volume Center: A Comparative Study with Inpatient Procedures

Feasibility and Safety of Ambulatory Bariatric Surgery in a High-Volume Center: A Comparative Study with Inpatient Procedures | 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 Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Feasibility and Safety of Ambulatory Bariatric Surgery in a High-Volume Center: A Comparative Study with Inpatient Procedures Luciano Javier Deluca, Patricio Jose Maria Cal, Florencia Marchetti, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9012568/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Background Ambulatory bariatric surgery has emerged as a safe and efficient alternative to traditional inpatient care when performed in carefully selected patients within structured enhanced recovery programs. The implementation of Enhanced Recovery Protocols (ERPs) protocols has enabled significant reductions in length of stay, postoperative morbidity, and healthcare costs without compromising patient safety. However, limited data are available from Latin American high-volume centers. Objectives To compare the feasibility and safety of ambulatory versus inpatient bariatric surgery in patients operated between 2017 and 2022 at a high-volume specialized bariatric center in Buenos Aires, Argentina. Methods A retrospective comparative study including all consecutive bariatric procedures performed from January 2017 to December 2022 (N = 2505). Patients were divided into an inpatient group (n = 1713) and an ambulatory group (n = 792). A 1:1 matched-pair analysis (sex, age, BMI, preoperative weight loss, comorbidities, and procedure type) generated 313 patients per group. Primary outcomes were major complications, 48hr-readmissions, and 30-day reoperations. Statistical significance was set at p < 0.05. Results Major complications occurred in 1.9% of ambulatory patients versus 4.2% of inpatients (p = 0.161). Readmission rates were 1.9% and 2.6%, respectively (p = 0.788), and reoperation rates 0.6% versus 1.6% (p = 0.450). No mortality occurred. The success rate for same-day discharge among eligible patients was 98.0%. Conclusions Ambulatory bariatric surgery, within Enhanced Recovery Protocols (ERPs) and strict patient selection, is feasible and safe in a high-volume Latin American center, showing comparable outcomes to inpatient surgery while reducing hospitalization demands and healthcare costs. Figures Figure 1 Figure 2 Figure 3 Key Points - Ambulatory bariatric surgery, performed within structured ERPs, is feasible and safe in carefully selected patients. - Same-day discharge was achieved in 98% of eligible cases with no increase in major complications, readmissions, or reoperations. - Comparative analysis with inpatient procedures showed equivalent safety outcomes and potential for substantial healthcare cost reduction. - Implementation of optimized recovery pathways can expand surgical capacity without compromising patient safety in high-volume bariatric centers. Introduction Obesity is a chronic, multifactorial disease associated with significant morbidity, impaired quality of life, and reduced life expectancy ( 1 ). Bariatric and metabolic surgery remains the most effective long-term treatment for severe obesity and its associated metabolic disorders, achieving sustained weight loss and improvement in comorbidities with low perioperative mortality rates. ( 2 ) During the past two decades, the implementation of Enhanced Recovery After Protocols (ERPs) has led to substantial advances in perioperative care, minimizing physiological stress, reducing length of stay (LOS), and improving postoperative outcomes ( 3 ). These protocols have allowed the progressive transition from inpatient to ambulatory (same-day discharge) bariatric surgery in appropriately selected patients. Several studies from the United States, Europe, and Asia have demonstrated that outpatient bariatric surgery can be safely implemented under ERPs programs, provided that patient selection is stringent and perioperative pathways standardized. Reported benefits include lower healthcare costs, faster recovery, and greater hospital bed availability, with no increase in postoperative complications or readmissions.( 4 ) Evidence from Latin American centers remains limited. In Argentina, our group reported the feasibility and safety of sleeve gastrectomy performed with short-stay hospitalization (less than 24 hours) ( 5 ). However, the feasibility of same-day bariatric surgery had not been comprehensively assessed despite increasing surgical volumes and the growing need to optimize hospital resources. The COVID-19 pandemic further accelerated the adoption of ambulatory surgical protocols to alleviate inpatient demand while maintaining patient safety. The present study aimed to evaluate the feasibility and safety of ambulatory bariatric surgery compared with inpatient surgery in a high-volume center in Buenos Aires, Argentina, using prospectively collected data from 2017 to 2022. Materials and Methods Study population and sample This study included all patients who underwent bariatric surgery between January 2017 and December 2022 at a high-volume bariatric center (N = 2,505). The year 2017 was selected as the starting point because, by that time, all participating surgeons had completed their learning curves for the bariatric procedures performed, thereby minimizing operator-related bias in the analysis. Patients were classified into two groups: Ambulatory group – patients operated between 2021 and 2022 who met inclusion criteria for same-day discharge and presented no exclusion criteria. Inpatient group – patients operated between 2017 and 2020 (standard 24-hour admission) and those between 2021 and 2022 who did not meet criteria for ambulatory surgery or were excluded intra- or postoperatively. Additionally, three subgroups were analyzed according to discharge modality: ( 1 ) ambulatory by medical criteria, ( 2 ) inpatient by medical indication (e.g., BMI, comorbidities, complexity), and ( 3 ) eligible ambulatory cases requiring admission for operational reasons (late schedule, distant residence, etc.). Inclusion and exclusion criteria Inclusion criteria : age < 65 years, BMI < 65 kg/m², residence < 50 km or less than 1 hour from the surgical center, and independent mobility. Exclusion criteria : severe systemic disease or anticoagulant therapy, surgeon’s discretion, surgery ending after 14:00 h, intraoperative complications (bleeding, adhesions, instability), need for drain placement, or patient refusal of same-day discharge. Variables Primary variables assessed the feasibility and safety of implementing an enhanced recovery ambulatory bariatric surgery protocol. Feasibility included appropriate patient selection, postoperative hemodynamic stability, adequate pain control and liquid oral intake, 24/7 access to the surgical team, and availability of a hospital network for urgent readmission. Safety variables included rates of readmission and reoperation within 48 hours due to procedure-related complications (intra-abdominal or endoluminal bleeding, intolerance, uncontrolled pain, or thromboembolic events). Mortality was not analyzed as no 30-day mortality was reported during the study period. Secondary variables included demographic and anthropometric factors (age, sex, BMI, preoperative weight loss) and metabolic comorbidities (T2DM, hypertension, dyslipidemia), considered non-significant for primary outcome analysis but relevant for matching and subgroup characterization. Enhanced Recovery Protocol (ERP) A standardized ERP pathway was applied as a multidisciplinary approach to optimize outcomes in bariatric patients. The protocol incorporated perioperative strategies to reduce physiological stress, minimize pain, and promote early recovery. Preoperative phase : Patient education, shortened fasting with intake of isotonic fluids until a few hours before surgery, and administration of nonsteroidal anti-inflammatory drugs (NSAIDs) were used to enhance analgesia and attenuate the metabolic stress response. Intraoperative phase : Minimally invasive laparoscopic techniques were employed whenever possible. Local anesthetic infiltration was performed at all trocar sites and intraperitoneally, combined with meticulous hemostasis and suction of residual blood to minimize peritoneal irritation. A multimodal analgesic regimen including corticosteroids, antiemetics, and antispasmodics was used, minimizing opioid consumption. Postoperative phase : Early mobilization and oral liquid intake were encouraged to prevent thromboembolic and pulmonary complications. Pain was managed with NSAIDs and regional analgesia when indicated. This ERP aimed to improve recovery, reduce complications, and shorten hospital stay without compromising patient safety. Data Processing and Statistical Analysis Surgical data were extracted from the institutional registry (FileMaker Pro 11 Advanced) and exported anonimaly to Microsoft Excel for filtering and tabulation according to inclusion and exclusion criteria. Numerical variables were expressed as means ± standard deviation, and categorical variables as proportions. Comparisons between groups were performed using the independent-samples t test for quantitative variables and Fisher’s exact or chi-square tests for categorical variables. A two-tailed p-value < 0.05 was considered statistically significant. To minimize selection bias from the non-random allocation of ambulatory versus inpatient surgery, a propensity score matching (PSM) model was applied using sex, age, BMI, preoperative weight loss, comorbidities, HbA1c, and procedure type as covariates, with 1:1 nearest-neighbor pairing. Analyses were performed using IBM SPSS Statistics version 26 (IBM Corp., USA). Ethical Considerations The study was approved by the Biomedical Ethics Committee of Churruca Medical Complex (Buenos Aires, Argentina), where the author serves as staff surgeon of the Bariatric Surgery Program. All procedures complied with the Declaration of Helsinki, national research ethics guidelines (Resolution 1480/11, Ministry of Health), and the Personal Data Protection Law 25.326. Given its retrospective observational design, the requirement for informed consent was waived. Results Between January 2017 and December 2022, a total of 2,505 patients underwent bariatric surgery, including 2,106 women (84.1%), with a mean age of 40.7 years (range 14–69; SD 37.3) and a mean BMI of 45.0 kg/m² (22.2–85.5; SD 5.97). The mean BMI by age percentile was 40.6 kg/m² (P25), 43.6 kg/m² (P50), and 48.1 kg/m² (P75). The overall prevalence of metabolic comorbidities was type 2 diabetes (T2DM) 14.9%, hypertension (HTN) 29%, and dyslipidemia 29%. (Table 1 ) Table 1 Overall Population Variable Post matching (n = 626) Age 40,73 (14–69 DD: 37,3) Women (%) 84,1% BMI 45,02kg/m2 (22,2–85,53 DD: 5,97) - P25 40,63kg/m2 - P50 43,56kg/m2 - P75 48,08kg/m2 Diabetes (%) 14,9% HTN (%) 29% Dyslipidemia (%) 29% Surgical distribution Among all procedures, sleeve gastrectomy accounted for 1,843 cases (73.6%), one-anastomosis gastric bypass (OAGB) for 479 (19.1%), Roux-en-Y gastric bypass (RYGB) for 86 (3.4%), revisional procedures for 88 (3.5%), and other techniques for 9 (0.4%). (FIGURE 1 ) Hospitalization modality The COVID-19 pandemic prompted a modification of postoperative management. Before March 2020, all patients were admitted for 24 hours post-surgery. After elective activity resumed in March 2021, a structured ambulatory surgery protocol was implemented, allowing same-day discharge (6–8 h postoperative observation) for patients meeting predefined inclusion criteria. Overall, 1,713 cases (68.4%) involved 24-hour hospitalization and 792 (31.6%) were managed as ambulatory procedures. Of the inpatient cases, 1,527 (89.1%) occurred before March 2020, while 186 (10.9%) took place after March 2021 in patients who did not qualify for ambulatory management or required extended observation due to intra- or postoperative events. Among 978 patients operated after the ambulatory protocol implementation, 792 (81%) were successfully discharged on the same day. Reasons for exclusion included 137 patients (14%) not meeting preoperative criteria (age, BMI, comorbidities, distance, or surgical timing), 33 (3.4%) with intraoperative findings (adhesions, bleeding, hemodynamic instability, or drain requirement), and 16 (1.6%) who failed discharge due to poor pain control or gastrointestinal intolerance. (FIGURE 2 ) When only eligible candidates were considered (n = 808), the success rate for ambulatory surgery was 98.0%, with 1.98% (n = 16) requiring overnight admission. Readmissions and reoperations In the ambulatory cohort (n = 742), 12 patients (1.6%) required readmission, mainly for bleeding (n = 10; 83.3%), and 5 (0.67%) underwent reoperation (3 intra-abdominal, 2 gastrointestinal hemorrhages). All patients maintained direct postoperative phone contact with the surgical team, and given that all lived within 40 km and had personal transportation, readmissions occurred within two hours of initial contact. Comparative analysis To compare outcomes between groups, a 1:1 propensity score matching was performed based on sex, age, BMI, preoperative weight loss, comorbidities, HbA1c level, and surgical type, resulting in 626 matched patients (313 ambulatory vs. 313 inpatient). Baseline variables showed no significant differences except for BMI, which was slightly higher in the inpatient group (45.8 vs. 44.6 kg/m², not clinically relevant). (Table 2 ) Table 2 Post-matching ambulatory and inpatient group population. Variable Post matching (n = 626) P value Inpatient Ambulatory Age 35,86 (10,21) 40,62 (9,84) 0,413 Women (%) 81,5 86,9 0,079 BMI 45,82 (6,20) 44,58 (6,94) 0,019 %preopWL 11,51 (5,50) 11,91 (5,60) 0,377 Diabetes (%) 15 13,1 0,566 HbAc1 5,75 (0,85) 5,73 (0,87) 0,695 Dyslipidemia (%) 23 24,6 0,707 HTN (%) 26,5 25,9 0,928 After matching, major complications occurred in 1.9% of ambulatory and 4.2% of inpatient cases (p = 0.161). Readmission rates were 1.9% vs. 2.6% (p = 0.788) and reoperation rates were 0.6% vs. 1.6% (p = 0.450). (Table 3 and FIGURE 3 ). Although not statistically significant, all outcomes demonstrated a favorable trend toward ambulatory procedures. Table 3 Comparative analysis of complications, readmissions and reinterventions Variable Post matching (n = 626) P value Inpatient Ambulatory Complication (%) 4,2 1,9 0,161 Readmission (%) 2,6 1,9 0,788 Reoperation (%) 1,6 0,6 0,450 Discussion The implementation of Enhanced Recovery Protocols has transformed perioperative management, including bariatric surgery. Beyond clear economic advantages for healthcare systems—reducing costs and inpatient bed occupancy—this approach optimizes surgical throughput and shortens patient waiting times for elective procedures. Several studies have confirmed these benefits: Fleming first reported a 25% cost reduction in outpatient laparoscopic cholecystectomy compared with inpatient care ( 6 ), while Teixeira (2016) ( 7 ) and Manzia (2020) ( 8 ) observed 35–300% reductions in total hospital expenditures and improved bed turnover in Latin American and European series. A meta-analysis by Friedlander (2019), including more than 73,000 patients, demonstrated significantly lower direct and 30-day costs for ambulatory surgery across multiple general procedures ( 9 ). Patient acceptance has also been consistently high. Fassiadis (2004) reported > 90% satisfaction after outpatient cholecystectomy ( 10 ), and Kleipool (2024) confirmed similarly favorable perceptions using the BODY-Q scale in ambulatory gastric bypass ( 11 ). Shorter hospitalization enhances comfort and autonomy while minimizing disruption of daily activities, a benefit particularly valuable for pediatric and elderly populations ( 12 – 13 ). Ambulatory surgery represents a cost-effective and safe management model that maintains quality of care while expanding surgical access. During the COVID-19 pandemic, this modality proved essential to sustain elective activity while preserving inpatient capacity for infected patients. Literature reviews have estimated overall savings of 25–65%, driven by reduced bed occupancy, operating room optimization, and fewer cancellations ( 14 ). The experience in our center during the pandemic mirrored these findings, as ambulatory bariatric protocols allowed continued access to essential treatment for morbid obesity—one of the main modifiable risk factors for severe COVID-19—while minimizing exposure risk and conserving hospital resources. Safety concerns remain the main barrier to wider adoption of outpatient bariatric surgery. However, evidence indicates that with appropriate patient selection and surgical expertise, outcomes are equivalent to inpatient care. Warner (1993) showed no increase in morbidity in outpatient procedures ( 15 ), and our previous series of short-stay sleeve gastrectomy (mean stay 18 h) already demonstrated low bleeding (0.87%), intolerance (0.61%), and readmission (0.15%) rates, with all major complications occurring after postoperative day 5 ( 5 ). These findings supported our transition to true same-day discharge. Comparable evidence supports these results. Inaba (2018), analyzing MBSAQIP data, found higher morbidity and readmissions among poorly selected outpatient cases, emphasizing the importance of inclusion criteria ( 16 ). In contrast, in our series—where criteria were strictly applied—complications, readmissions, and reoperations were lower, albeit without statistical significance. Our selection parameters were broader than most published series, including patients up to BMI 60 kg/m² and age 55 years, and encompassing both primary and revisional procedures, a distinctive feature not reported in previous studies. Consistent with Vanetta’s 2023 meta-analysis of 33,403 ambulatory bariatric cases, our findings confirm high feasibility and safety ( 17 ). The meta-analysis reported a ~ 90% success rate for same-day discharge and readmission rates of 0.6–8.5%, comparable to our 1.6%. Gastrointestinal intolerance was the most common cause of readmission in prior reports, whereas in our series 83.3% of readmissions were due to hemorrhage, and no deaths occurred. Limitations of this study include its single-center design and operations performed by the same experienced team, which could bias outcomes toward lower complication rates. However, since all surgeons had completed their learning curves before 2017, this effect is likely minimal. Additionally, smoking status was excluded from analysis due to underreporting before 2020. Overall, our findings demonstrate that ambulatory bariatric surgery is feasible, safe, and cost-effective when applied within well-defined selection and recovery protocols. Importantly, its feasibility and safety rely not only on the strict application of preoperative inclusion criteria but also on the experience and clinical judgment of the surgical team in identifying, during the intraoperative phase, those patients who should be excluded from same-day discharge due to specific events or conditions. This combined approach provides a sustainable alternative for healthcare systems operating under capacity constraints. Conclusion To our knowledge, this is the first study comparing outcomes of ambulatory versus inpatient bariatric surgery performed by the same surgical team after completion of the learning curve. In this series, ambulatory bariatric surgery proved to be feasible and safe within our setting when compared with inpatient bariatric surgery, while providing the well-documented advantages of this modality—namely, reduced healthcare costs, optimized use of hospital beds and operating room schedules for elective procedures, and earlier return to work. The implementation of enhanced recovery protocols and the strict adherence to well-defined inclusion and exclusion criteria are essential to ensure that ambulatory bariatric surgery can be performed with safe outcomes equivalent to inpatient management. Declarations Ethical Statements Ethical approval: Conducted per institutional and national committees based on the 1964 Helsinki Declaration. Informed consent: All patients provided consent for inclusion in the institutional database. Conflict of interest: The author is speaker for EziSurg Medical. Funding: No external funding was received. Author Contribution L.D. wrote the main manuscript text. P.C. performed the statistical analysis. F.M. and S.G. were responsible for patient recruitment and updating clinical records. E.F. carried out the final revisions and corrections of the manuscript. All authors reviewed the manuscript References OMS. (2024, March 1). Obesidad y Sobrepeso. Organización Mundial de la Salud. https://www.who.int/es/news-room/fact-sheets/detail/obesity-and-overweight Caceres Tavara y Espinoza Solano. (2023). Efectividad de la cirugía bariátrica en pacientes adultos con obesidad e hipertensión arterial: una revisión sistemática de revisiones sistemáticas. https://repositorio.cientifica.edu.pe/handle/20.500.12805/2211 Parisi A, Desiderio J, Cirocchi R, Trastulli S. Enhanced Recovery after Surgery (ERAS): a Systematic Review of Randomised Controlled Trials (RCTs) in Bariatric Surgery. Obes Surg. 2020. https://doi.org/10.1007/s11695-020-05000-6 . 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Patient Satisfaction and Experience with Same-Day Discharge After Laparoscopic Roux-en-Y Gastric Bypass: A Mixed-Methods study. Obes Surg. 2024 May 25. 10.1007/s11695-024-07264-8 . Epub ahead of print. PMID: 38795202. Castoro C. Policy Brief Day Surgery: Making it Happen. IASS, 2007 www. euro.who.int/document/e90295 Letts M, Davidson D, et al. Analysis of the efficacy of pediatric day surgery. Can J Surg. 2001;44(3):193–8. Recart A. CIRUGÍA MAYOR AMBULATORIA. UNA NUEVA FORMA DE ENTENDER LA MEDICINA QUIRÚRGICA. Revista Médica Clínica Las Condes. 2017;28:682–90. Warner MA, Shields SE, Chute CG. Major morbidity and mortality within 1 month of ambulatory surgery and anesthesia. JAMA. 1993;270:1437–41. Inaba CS, Koh CY, Sujatha-Bhaskar S, Pejcinovska M, Nguyen NT. How safe is same-day discharge after laparoscopic sleeve gastrectomy? Surg Obes Relat Dis. 2018;14(10):1448–53. 10.1016/j.soard.2018.07.016 . Epub 2018 Jul 21. PMID: 30145057. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board 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-9012568","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":607379393,"identity":"f4930c56-f261-4dd1-9598-dda5eca82951","order_by":0,"name":"Luciano Javier 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performed.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9012568/v1/98f345e958d4ab533b2ced0c.png"},{"id":104996206,"identity":"490c6f91-891d-4ad7-a984-3ef5e6f58ca3","added_by":"auto","created_at":"2026-03-19 16:11:41","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":54613,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePatient distribution after the ERP implementation\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9012568/v1/0672af0a4ad9c6c9339581eb.png"},{"id":104996210,"identity":"3b55d589-6d8d-448d-b6e4-be1e71b763df","added_by":"auto","created_at":"2026-03-19 16:11:41","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":26190,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eComparative analysis of complications, readmissions and reinterventions\u003c/em\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-9012568/v1/1c9a727e277b4dec1c8ef55a.png"},{"id":105035454,"identity":"2e15dd24-0934-4421-ac4d-abb9987d150a","added_by":"auto","created_at":"2026-03-20 07:26:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":757329,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9012568/v1/d463ec7e-5228-4906-9f5d-554313c6f49a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Feasibility and Safety of Ambulatory Bariatric Surgery in a High-Volume Center: A Comparative Study with Inpatient Procedures","fulltext":[{"header":"Key Points","content":"\u003cp\u003e- Ambulatory bariatric surgery, performed within structured ERPs, is feasible and safe in carefully selected patients.\u003c/p\u003e\u003cp\u003e- Same-day discharge was achieved in 98% of eligible cases with no increase in major complications, readmissions, or reoperations.\u003c/p\u003e\u003cp\u003e- Comparative analysis with inpatient procedures showed equivalent safety outcomes and potential for substantial healthcare cost reduction.\u003c/p\u003e\u003cp\u003e- Implementation of optimized recovery pathways can expand surgical capacity without compromising patient safety in high-volume bariatric centers.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eObesity is a chronic, multifactorial disease associated with significant morbidity, impaired quality of life, and reduced life expectancy (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Bariatric and metabolic surgery remains the most effective long-term treatment for severe obesity and its associated metabolic disorders, achieving sustained weight loss and improvement in comorbidities with low perioperative mortality rates. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eDuring the past two decades, the implementation of Enhanced Recovery After Protocols (ERPs) has led to substantial advances in perioperative care, minimizing physiological stress, reducing length of stay (LOS), and improving postoperative outcomes (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). These protocols have allowed the progressive transition from inpatient to ambulatory (same-day discharge) bariatric surgery in appropriately selected patients.\u003c/p\u003e \u003cp\u003eSeveral studies from the United States, Europe, and Asia have demonstrated that outpatient bariatric surgery can be safely implemented under ERPs programs, provided that patient selection is stringent and perioperative pathways standardized. Reported benefits include lower healthcare costs, faster recovery, and greater hospital bed availability, with no increase in postoperative complications or readmissions.(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eEvidence from Latin American centers remains limited. In Argentina, our group reported the feasibility and safety of sleeve gastrectomy performed with short-stay hospitalization (less than 24 hours) (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). However, the feasibility of same-day bariatric surgery had not been comprehensively assessed despite increasing surgical volumes and the growing need to optimize hospital resources. The COVID-19 pandemic further accelerated the adoption of ambulatory surgical protocols to alleviate inpatient demand while maintaining patient safety.\u003c/p\u003e \u003cp\u003eThe present study aimed to evaluate the feasibility and safety of ambulatory bariatric surgery compared with inpatient surgery in a high-volume center in Buenos Aires, Argentina, using prospectively collected data from 2017 to 2022.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy population and sample\u003c/h2\u003e \u003cp\u003eThis study included all patients who underwent bariatric surgery between January 2017 and December 2022 at a high-volume bariatric center (N\u0026thinsp;=\u0026thinsp;2,505).\u003c/p\u003e \u003cp\u003eThe year 2017 was selected as the starting point because, by that time, all participating surgeons had completed their learning curves for the bariatric procedures performed, thereby minimizing operator-related bias in the analysis.\u003c/p\u003e \u003cp\u003ePatients were classified into two groups:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eAmbulatory group\u003c/span\u003e \u0026ndash; patients operated between 2021 and 2022 who met inclusion criteria for same-day discharge and presented no exclusion criteria.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInpatient group\u003c/span\u003e \u0026ndash; patients operated between 2017 and 2020 (standard 24-hour admission) and those between 2021 and 2022 who did not meet criteria for ambulatory surgery or were excluded intra- or postoperatively.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eAdditionally, three subgroups were analyzed according to discharge modality: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) ambulatory by medical criteria, (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) inpatient by medical indication (e.g., BMI, comorbidities, complexity), and (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) eligible ambulatory cases requiring admission for operational reasons (late schedule, distant residence, etc.).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eInclusion and exclusion criteria\u003c/h3\u003e\n\u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInclusion criteria\u003c/span\u003e: age\u0026thinsp;\u0026lt;\u0026thinsp;65 years, BMI\u0026thinsp;\u0026lt;\u0026thinsp;65 kg/m\u0026sup2;, residence\u0026thinsp;\u0026lt;\u0026thinsp;50 km or less than 1 hour from the surgical center, and independent mobility.\u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eExclusion criteria\u003c/span\u003e: severe systemic disease or anticoagulant therapy, surgeon\u0026rsquo;s discretion, surgery ending after 14:00 h, intraoperative complications (bleeding, adhesions, instability), need for drain placement, or patient refusal of same-day discharge.\u003c/p\u003e\n\u003ch3\u003eVariables\u003c/h3\u003e\n\u003cp\u003ePrimary variables assessed the \u003cb\u003efeasibility\u003c/b\u003e and \u003cb\u003esafety\u003c/b\u003e of implementing an enhanced recovery ambulatory bariatric surgery protocol. \u003cb\u003eFeasibility\u003c/b\u003e included appropriate patient selection, postoperative hemodynamic stability, adequate pain control and liquid oral intake, 24/7 access to the surgical team, and availability of a hospital network for urgent readmission.\u003c/p\u003e \u003cp\u003e \u003cb\u003eSafety\u003c/b\u003e variables included rates of readmission and reoperation within 48 hours due to procedure-related complications (intra-abdominal or endoluminal bleeding, intolerance, uncontrolled pain, or thromboembolic events). Mortality was not analyzed as no 30-day mortality was reported during the study period.\u003c/p\u003e \u003cp\u003eSecondary variables included demographic and anthropometric factors (age, sex, BMI, preoperative weight loss) and metabolic comorbidities (T2DM, hypertension, dyslipidemia), considered non-significant for primary outcome analysis but relevant for matching and subgroup characterization.\u003c/p\u003e\n\u003ch3\u003eEnhanced Recovery Protocol (ERP)\u003c/h3\u003e\n\u003cp\u003eA standardized ERP pathway was applied as a multidisciplinary approach to optimize outcomes in bariatric patients. The protocol incorporated perioperative strategies to reduce physiological stress, minimize pain, and promote early recovery.\u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePreoperative phase\u003c/span\u003e: Patient education, shortened fasting with intake of isotonic fluids until a few hours before surgery, and administration of nonsteroidal anti-inflammatory drugs (NSAIDs) were used to enhance analgesia and attenuate the metabolic stress response.\u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eIntraoperative phase\u003c/span\u003e: Minimally invasive laparoscopic techniques were employed whenever possible. Local anesthetic infiltration was performed at all trocar sites and intraperitoneally, combined with meticulous hemostasis and suction of residual blood to minimize peritoneal irritation. A multimodal analgesic regimen including corticosteroids, antiemetics, and antispasmodics was used, minimizing opioid consumption.\u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePostoperative phase\u003c/span\u003e: Early mobilization and oral liquid intake were encouraged to prevent thromboembolic and pulmonary complications. Pain was managed with NSAIDs and regional analgesia when indicated.\u003c/p\u003e \u003cp\u003eThis ERP aimed to improve recovery, reduce complications, and shorten hospital stay without compromising patient safety.\u003c/p\u003e\n\u003ch3\u003eData Processing and Statistical Analysis\u003c/h3\u003e\n\u003cp\u003eSurgical data were extracted from the institutional registry (FileMaker Pro 11 Advanced) and exported anonimaly to Microsoft Excel for filtering and tabulation according to inclusion and exclusion criteria. Numerical variables were expressed as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and categorical variables as proportions.\u003c/p\u003e \u003cp\u003eComparisons between groups were performed using the independent-samples t test for quantitative variables and Fisher\u0026rsquo;s exact or chi-square tests for categorical variables. A two-tailed p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003cp\u003eTo minimize selection bias from the non-random allocation of ambulatory versus inpatient surgery, a propensity score matching (PSM) model was applied using sex, age, BMI, preoperative weight loss, comorbidities, HbA1c, and procedure type as covariates, with 1:1 nearest-neighbor pairing. Analyses were performed using IBM SPSS Statistics version 26 (IBM Corp., USA).\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eEthical Considerations\u003c/h2\u003e \u003cp\u003e The study was approved by the Biomedical Ethics Committee of Churruca Medical Complex (Buenos Aires, Argentina), where the author serves as staff surgeon of the Bariatric Surgery Program. All procedures complied with the Declaration of Helsinki, national research ethics guidelines (Resolution 1480/11, Ministry of Health), and the Personal Data Protection Law 25.326. Given its retrospective observational design, the requirement for informed consent was waived.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eBetween January 2017 and December 2022, a total of 2,505 patients underwent bariatric surgery, including 2,106 women (84.1%), with a mean age of 40.7 years (range 14\u0026ndash;69; SD 37.3) and a mean BMI of 45.0 kg/m\u0026sup2; (22.2\u0026ndash;85.5; SD 5.97). The mean BMI by age percentile was 40.6 kg/m\u0026sup2; (P25), 43.6 kg/m\u0026sup2; (P50), and 48.1 kg/m\u0026sup2; (P75).\u003c/p\u003e \u003cp\u003eThe overall prevalence of metabolic comorbidities was type 2 diabetes (T2DM) 14.9%, hypertension (HTN) 29%, and dyslipidemia 29%. (Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOverall Population\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost matching (n\u0026thinsp;=\u0026thinsp;626)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40,73 (14\u0026ndash;69 DD: 37,3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWomen (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e84,1%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45,02kg/m2 (22,2\u0026ndash;85,53 DD: 5,97)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- P25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40,63kg/m2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- P50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43,56kg/m2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- P75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48,08kg/m2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14,9%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHTN (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDyslipidemia (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eSurgical distribution\u003c/h3\u003e\n\u003cp\u003eAmong all procedures, sleeve gastrectomy accounted for 1,843 cases (73.6%), one-anastomosis gastric bypass (OAGB) for 479 (19.1%), Roux-en-Y gastric bypass (RYGB) for 86 (3.4%), revisional procedures for 88 (3.5%), and other techniques for 9 (0.4%). (FIGURE \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eHospitalization modality\u003c/h2\u003e \u003cp\u003eThe COVID-19 pandemic prompted a modification of postoperative management. Before March 2020, all patients were admitted for 24 hours post-surgery. After elective activity resumed in March 2021, a structured ambulatory surgery protocol was implemented, allowing same-day discharge (6\u0026ndash;8 h postoperative observation) for patients meeting predefined inclusion criteria.\u003c/p\u003e \u003cp\u003eOverall, 1,713 cases (68.4%) involved 24-hour hospitalization and 792 (31.6%) were managed as ambulatory procedures. Of the inpatient cases, 1,527 (89.1%) occurred before March 2020, while 186 (10.9%) took place after March 2021 in patients who did not qualify for ambulatory management or required extended observation due to intra- or postoperative events.\u003c/p\u003e \u003cp\u003eAmong 978 patients operated after the ambulatory protocol implementation, 792 (81%) were successfully discharged on the same day. Reasons for exclusion included 137 patients (14%) not meeting preoperative criteria (age, BMI, comorbidities, distance, or surgical timing), 33 (3.4%) with intraoperative findings (adhesions, bleeding, hemodynamic instability, or drain requirement), and 16 (1.6%) who failed discharge due to poor pain control or gastrointestinal intolerance. (FIGURE \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWhen only eligible candidates were considered (n\u0026thinsp;=\u0026thinsp;808), the success rate for ambulatory surgery was 98.0%, with 1.98% (n\u0026thinsp;=\u0026thinsp;16) requiring overnight admission.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eReadmissions and reoperations\u003c/h2\u003e \u003cp\u003eIn the ambulatory cohort (n\u0026thinsp;=\u0026thinsp;742), 12 patients (1.6%) required readmission, mainly for bleeding (n\u0026thinsp;=\u0026thinsp;10; 83.3%), and 5 (0.67%) underwent reoperation (3 intra-abdominal, 2 gastrointestinal hemorrhages). All patients maintained direct postoperative phone contact with the surgical team, and given that all lived within 40 km and had personal transportation, readmissions occurred within two hours of initial contact.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eComparative analysis\u003c/h2\u003e \u003cp\u003eTo compare outcomes between groups, a 1:1 propensity score matching was performed based on sex, age, BMI, preoperative weight loss, comorbidities, HbA1c level, and surgical type, resulting in 626 matched patients (313 ambulatory vs. 313 inpatient). Baseline variables showed no significant differences except for BMI, which was slightly higher in the inpatient group (45.8 vs. 44.6 kg/m\u0026sup2;, not clinically relevant). (Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePost-matching ambulatory and inpatient group population.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003ePost matching (n\u0026thinsp;=\u0026thinsp;626)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInpatient\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAmbulatory\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35,86 (10,21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40,62 (9,84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,413\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWomen (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e81,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e86,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,079\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45,82 (6,20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44,58 (6,94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,019\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e%preopWL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11,51 (5,50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11,91 (5,60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,377\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13,1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,566\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHbAc1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5,75 (0,85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5,73 (0,87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,695\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDyslipidemia (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,707\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHTN (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,928\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAfter matching, major complications occurred in 1.9% of ambulatory and 4.2% of inpatient cases (p\u0026thinsp;=\u0026thinsp;0.161). Readmission rates were 1.9% vs. 2.6% (p\u0026thinsp;=\u0026thinsp;0.788) and reoperation rates were 0.6% vs. 1.6% (p\u0026thinsp;=\u0026thinsp;0.450). (Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e \u003cb\u003eand\u003c/b\u003e FIGURE \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Although not statistically significant, all outcomes demonstrated a favorable trend toward ambulatory procedures.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparative analysis of complications, readmissions and reinterventions\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003ePost matching (n\u0026thinsp;=\u0026thinsp;626)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInpatient\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAmbulatory\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eComplication (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,161\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReadmission (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,788\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReoperation (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,450\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe implementation of Enhanced Recovery Protocols has transformed perioperative management, including bariatric surgery. Beyond clear economic advantages for healthcare systems\u0026mdash;reducing costs and inpatient bed occupancy\u0026mdash;this approach optimizes surgical throughput and shortens patient waiting times for elective procedures. Several studies have confirmed these benefits: Fleming first reported a 25% cost reduction in outpatient laparoscopic cholecystectomy compared with inpatient care (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e), while Teixeira (2016) (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) and Manzia (2020) (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) observed 35\u0026ndash;300% reductions in total hospital expenditures and improved bed turnover in Latin American and European series. A meta-analysis by Friedlander (2019), including more than 73,000 patients, demonstrated significantly lower direct and 30-day costs for ambulatory surgery across multiple general procedures (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003ePatient acceptance has also been consistently high. Fassiadis (2004) reported\u0026thinsp;\u0026gt;\u0026thinsp;90% satisfaction after outpatient cholecystectomy (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e), and Kleipool (2024) confirmed similarly favorable perceptions using the BODY-Q scale in ambulatory gastric bypass (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Shorter hospitalization enhances comfort and autonomy while minimizing disruption of daily activities, a benefit particularly valuable for pediatric and elderly populations (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAmbulatory surgery represents a cost-effective and safe management model that maintains quality of care while expanding surgical access. During the COVID-19 pandemic, this modality proved essential to sustain elective activity while preserving inpatient capacity for infected patients. Literature reviews have estimated overall savings of 25\u0026ndash;65%, driven by reduced bed occupancy, operating room optimization, and fewer cancellations (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). The experience in our center during the pandemic mirrored these findings, as ambulatory bariatric protocols allowed continued access to essential treatment for morbid obesity\u0026mdash;one of the main modifiable risk factors for severe COVID-19\u0026mdash;while minimizing exposure risk and conserving hospital resources.\u003c/p\u003e \u003cp\u003eSafety concerns remain the main barrier to wider adoption of outpatient bariatric surgery. However, evidence indicates that with appropriate patient selection and surgical expertise, outcomes are equivalent to inpatient care. Warner (1993) showed no increase in morbidity in outpatient procedures (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e), and our previous series of short-stay sleeve gastrectomy (mean stay 18 h) already demonstrated low bleeding (0.87%), intolerance (0.61%), and readmission (0.15%) rates, with all major complications occurring after postoperative day 5 (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). These findings supported our transition to true same-day discharge.\u003c/p\u003e \u003cp\u003eComparable evidence supports these results. Inaba (2018), analyzing MBSAQIP data, found higher morbidity and readmissions among poorly selected outpatient cases, emphasizing the importance of inclusion criteria (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). In contrast, in our series\u0026mdash;where criteria were strictly applied\u0026mdash;complications, readmissions, and reoperations were lower, albeit without statistical significance. Our selection parameters were broader than most published series, including patients up to BMI 60 kg/m\u0026sup2; and age 55 years, and encompassing both primary and revisional procedures, a distinctive feature not reported in previous studies.\u003c/p\u003e \u003cp\u003eConsistent with Vanetta\u0026rsquo;s 2023 meta-analysis of 33,403 ambulatory bariatric cases, our findings confirm high feasibility and safety (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). The meta-analysis reported a\u0026thinsp;~\u0026thinsp;90% success rate for same-day discharge and readmission rates of 0.6\u0026ndash;8.5%, comparable to our 1.6%. Gastrointestinal intolerance was the most common cause of readmission in prior reports, whereas in our series 83.3% of readmissions were due to hemorrhage, and no deaths occurred.\u003c/p\u003e \u003cp\u003eLimitations of this study include its single-center design and operations performed by the same experienced team, which could bias outcomes toward lower complication rates. However, since all surgeons had completed their learning curves before 2017, this effect is likely minimal. Additionally, smoking status was excluded from analysis due to underreporting before 2020.\u003c/p\u003e \u003cp\u003eOverall, our findings demonstrate that ambulatory bariatric surgery is feasible, safe, and cost-effective when applied within well-defined selection and recovery protocols. Importantly, its feasibility and safety rely not only on the strict application of preoperative inclusion criteria but also on the experience and clinical judgment of the surgical team in identifying, during the intraoperative phase, those patients who should be excluded from same-day discharge due to specific events or conditions. This combined approach provides a sustainable alternative for healthcare systems operating under capacity constraints.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eTo our knowledge, this is the first study comparing outcomes of ambulatory versus inpatient bariatric surgery performed by the same surgical team after completion of the learning curve.\u003c/p\u003e \u003cp\u003eIn this series, ambulatory bariatric surgery proved to be feasible and safe within our setting when compared with inpatient bariatric surgery, while providing the well-documented advantages of this modality\u0026mdash;namely, reduced healthcare costs, optimized use of hospital beds and operating room schedules for elective procedures, and earlier return to work.\u003c/p\u003e \u003cp\u003eThe implementation of enhanced recovery protocols and the strict adherence to well-defined inclusion and exclusion criteria are essential to ensure that ambulatory bariatric surgery can be performed with safe outcomes equivalent to inpatient management.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthical Statements\u003c/p\u003e\n\u003cp\u003eEthical approval: Conducted per institutional and national committees based on the 1964 Helsinki Declaration.\u003c/p\u003e\n\u003cp\u003eInformed consent: All patients provided consent for inclusion in the institutional database.\u003c/p\u003e\n\u003cp\u003eConflict of interest: The author is speaker for EziSurg Medical.\u003c/p\u003e\n\u003cp\u003eFunding: No external funding was received.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eL.D. wrote the main manuscript text. P.C. performed the statistical analysis. F.M. and S.G. were responsible for patient recruitment and updating clinical records. E.F. carried out the final revisions and corrections of the manuscript. All authors reviewed the manuscript\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eOMS. (2024, March 1). Obesidad y Sobrepeso. Organizaci\u0026oacute;n Mundial de la Salud. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.who.int/es/news-room/fact-sheets/detail/obesity-and-overweight\u003c/span\u003e\u003cspan address=\"https://www.who.int/es/news-room/fact-sheets/detail/obesity-and-overweight\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCaceres Tavara y Espinoza Solano. (2023). 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Surg Endosc (2016) 30:5596\u0026ndash;5600 \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00464-016-4933-7\u003c/span\u003e\u003cspan address=\"10.1007/s00464-016-4933-7\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFleming WR, Michell I, Douglas M. Audit of outpatient laparoscopic cholecystectomy. Universities of Melbourne HPB Group. Aust N Z J Surg. 2000;70(6):423- 7.\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1046/j.1440-1622.2000.01840.x\u003c/span\u003e\u003cspan address=\"10.1046/j.1440-1622.2000.01840.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 10843397.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTeixeira UF, Goldoni MB, Machry MC, Ceccon PN, Fontes PR, Waechter FL, AMBULATORY LAPAROSCOPIC CHOLECYSTECTOMY IS SAFE. 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Where Is the Value in Ambulatory Versus Inpatient Surgery? Ann Surg. 2021;273(5):909\u0026ndash;916. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/SLA.0000000000003578\u003c/span\u003e\u003cspan address=\"10.1097/SLA.0000000000003578\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 31460878.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFassiadis N, Pepas L, Grandy-Smith S, Paix A, El-Hasani S. Outcome and patient acceptance of outpatient laparoscopic cholecystectomy. JSLS. 2004 Jul-Sep;8(3):251\u0026ndash;3. PMID: 15347113; PMCID: PMC3016801.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKleipool SC, Willinge GJA, Mathijssen EGE, Romijnders KAGJ, de Castro SMM, Marsman HA, van Rutte PWJ, van Veen RN. Patient Satisfaction and Experience with Same-Day Discharge After Laparoscopic Roux-en-Y Gastric Bypass: A Mixed-Methods study. 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PMID: 36209031.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"obesity-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"obsu","sideBox":"Learn more about [Obesity Surgery](https://link.springer.com/journal/11695)","snPcode":"11695","submissionUrl":"https://submission.springernature.com/new-submission/11695/3","title":"Obesity Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-9012568/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9012568/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmbulatory bariatric surgery has emerged as a safe and efficient alternative to traditional inpatient care when performed in carefully selected patients within structured enhanced recovery programs. The implementation of Enhanced Recovery Protocols (ERPs) protocols has enabled significant reductions in length of stay, postoperative morbidity, and healthcare costs without compromising patient safety. However, limited data are available from Latin American high-volume centers.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjectives\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo compare the feasibility and safety of ambulatory versus inpatient bariatric surgery in patients operated between 2017 and 2022 at a high-volume specialized bariatric center in Buenos Aires, Argentina.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA retrospective comparative study including all consecutive bariatric procedures performed from January 2017 to December 2022 (N = 2505). Patients were divided into an inpatient group (n = 1713) and an ambulatory group (n = 792). A 1:1 matched-pair analysis (sex, age, BMI, preoperative weight loss, comorbidities, and procedure type) generated 313 patients per group. Primary outcomes were major complications, 48hr-readmissions, and 30-day reoperations. Statistical significance was set at p \u0026lt; 0.05.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMajor complications occurred in 1.9% of ambulatory patients versus 4.2% of inpatients (p = 0.161). Readmission rates were 1.9% and 2.6%, respectively (p = 0.788), and reoperation rates 0.6% versus 1.6% (p = 0.450). No mortality occurred. The success rate for same-day discharge among eligible patients was 98.0%.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmbulatory bariatric surgery, within Enhanced Recovery Protocols (ERPs) and strict patient selection, is feasible and safe in a high-volume Latin American center, showing comparable outcomes to inpatient surgery while reducing hospitalization demands and healthcare costs.\u003c/p\u003e","manuscriptTitle":"Feasibility and Safety of Ambulatory Bariatric Surgery in a High-Volume Center: A Comparative Study with Inpatient Procedures","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-19 16:11:35","doi":"10.21203/rs.3.rs-9012568/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-23T14:07:08+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-17T22:41:23+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-09T14:33:30+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-24T14:28:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"263764770440258440628702704359881146115","date":"2026-03-22T14:26:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"133419477909724894677132318035773795308","date":"2026-03-20T11:43:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"202509382480575301465775608908463546013","date":"2026-03-18T00:46:38+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-16T20:33:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-05T15:17:14+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-04T08:47:57+00:00","index":"","fulltext":""},{"type":"submitted","content":"Obesity Surgery","date":"2026-03-02T16:54:39+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"obesity-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"obsu","sideBox":"Learn more about [Obesity Surgery](https://link.springer.com/journal/11695)","snPcode":"11695","submissionUrl":"https://submission.springernature.com/new-submission/11695/3","title":"Obesity Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"eddefe7d-c9c0-4dc5-a193-0ac365407fa0","owner":[],"postedDate":"March 19th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-15T21:53:13+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-19 16:11:35","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9012568","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9012568","identity":"rs-9012568","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}