Initial Experience of Partial Nephrectomy and Retroperitoneal Organ Surgery using Supine Anterior Retroperitoneal Access (SARA) with the da Vinci SP Robotic System: Initial descriptive analysis

Initial Experience of Partial Nephrectomy and Retroperitoneal Organ Surgery using Supine Anterior Retroperitoneal Access (SARA) with the da Vinci SP Robotic System: Initial descriptive analysis | 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 Initial Experience of Partial Nephrectomy and Retroperitoneal Organ Surgery using Supine Anterior Retroperitoneal Access (SARA) with the da Vinci SP Robotic System: Initial descriptive analysis Hoyoung Bae, Ji Hyung Yoon, Seong Cheol Kim, Taekmin Kwon, Sungchan Park, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6926946/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose: This study aimed to describe the initial experience and perioperative outcomes of partial nephrectomy (PN) and other retroperitoneal organ surgeries using the supine anterior retroperitoneal access (SARA) technique with the da Vinci SP robotic system. Materials and Methods: Between December 2023 and December 2024, 35 retroperitoneal surgeries, including 25 PNs, were performed via SARA using a single-port robotic platform. The SARA approach utilizes anterior anatomical landmarks in the supine position to access retroperitoneal organs. Perioperative data, including operative time, warm ischemia time, estimated blood loss (EBL), postoperative renal function, length of stay (LOS), pain scores, and complications, were retrospectively reviewed. Results: Among 34 patients (mean age 60.3 years), PN was the most common procedure (73.5%). The mean tumor size for PN was 3.5 cm, and all were staged cT1a–b. There were no conversions to open surgery, no positive margins, and no major complications. Mean operative time was 200.6 minutes, warm ischemia time 21.3 minutes, and EBL 366.6 mL. Postoperative LOS averaged 7.1 days, and pain scores were well controlled (mean 2.4). sCr and hemoglobin changes were within acceptable limits. The SARA technique was also successfully applied to adrenalectomy, ureterectomy, and retroperitoneal mass excisions. Conclusions: SARA using the da Vinci SP platform is a feasible and safe approach for retroperitoneal surgeries, including PN and adrenalectomy. It offers advantages in patient positioning, surgical ergonomics, and recovery. Further studies are warranted to validate its role compared to traditional approaches and to define learning curve parameters. partial nephrectomy supine anterior retroperitoneal access retroperitoneal organ adrenal Figures Figure 1 Introduction In 2021, the incidence of kidney cancer in South Korea was reported 6,883, accounting for 2.5% of all cancer incidence and ranking tenth overall. The 5-year relative survival rate for kidney cancer has significantly improved from 64.2% during 1993-1995 to 86.4% in 2017-2021. This improvement can be largely attributed to advancements in robotic surgery [1]. In the United States, the proportion of robot-assisted partial nephrectomies (PNs) among all PNs increased from 20% to 49% between 2009 and 2012 [2]. After FDA approval of robot-assisted laparoscopic PN in 2011, this technique quickly became more prevalent than either laparoscopic PN or laparoscopic radical nephrectomy, surpassing them in 2012 and 2014, respectively [3]. Introduction of the da Vinci Single-Port (SP) system in 2018 marked a significant milestone in the development of minimally invasive surgery. This system, featuring a single 2.5-cm cannula for the insertion of a camera and three robotic arms, offers a less invasive approach than conventional multiport robotic platforms. This technological advancement is particularly beneficial in confined surgical spaces such as the retroperitoneum, enhancing instrument triangulation and dexterity [4,5]. The da Vinci SP system also enables targeting of specific anatomy during a procedure without compromising the less relevant surrounding structures, thus realizing the concept of “regionalization”. Following its introduction, there was a significant increase in the adoption of the retroperitoneal approach, with its usage increasing from 7.3% to 24.8% in a consortium of 12 institutions [6]. The supine anterior retroperitoneal access (SARA) is a minimally invasive surgical approach that enables direct anterior access to retroperitoneal organs, including the kidney and adrenal gland, with the patient in the supine position. Unlike conventional lateral decubitus retroperitoneal approaches, SARA utilizes anterior anatomical landmarks such as the psoas muscle and peritoneal reflection to develop the retroperitoneal space. This positioning improves ergonomics, facilitates simultaneous bilateral access if needed, and minimizes patient repositioning time. Since its first introduction by Pellegrino et al. in 2022, SARA has demonstrated feasibility in various retroperitoneal surgeries, such as partial nephrectomy, adrenalectomy, and lymph node dissection, and continues to expand its clinical indications. While some studies have referred to similar approaches as the low anterior approach (LAA), these were not exclusively performed in the supine position but involved both the decubitus and supine positions [7-9]. Therefore, supine anterior retroperitoneal access (SARA), first introduced and utilized by Pellegrino et al. is considered more appropriate in this context [10]. In South Korea, the use of da Vinci SP robots for retroperitoneal PNs has become increasingly common. Bang et al. reported 44 cases of PN using a da Vinci SP robot via a retroperitoneal approach; however, these procedures were performed in the lateral decubitus position [11]. In this paper, we describe our initial experiences and perioperative outcomes using this novel SARA technique with da Vinci SP robots, aiming to provide a safer, more efficient, and consistently reproducible method for 25 cases of PN, but also 9 cases of retroperitoneal organ surgery. Methods All surgical procedures were performed at a tertiary hospital by an expert surgeon from December 27, 2023, to December 18, 2024, using the da Vinci SP robotic system (Intuitive, Sunnyvale, CA, USA). This study was approved by the Institutional Review Board of a secondary medical center run by a university (approval number: 40-2025-4) and the requirement for informed consent was waived due to the retrospective nature of the study. Surgical Technique The patient was placed in the supine position and a 3-cm vertical incision was made approximately two-thirds laterally along the line from the umbilicus to the anterior superior iliac spine. The subcutaneous tissue was dissected, and the aponeurosis of the external oblique muscle was incised, after which the three muscle layers were bluntly separated. By finger dissection, the retroperitoneal space was prepared for the da Vinci SP access port (Intuitive, Sunnyvale, CA, USA), and a 12-mm AirSeal assistant port (ConMed Corp., Utica, NY, USA) was inserted in the lower part of the incision in a “sidecar” fashion. An AirSeal insufflation system (ConMed Corp., Utica, NY, USA) was used to maintain an insufflation pressure of 12 mmHg. Gas insufflation secures the retroperitoneal space without a balloon dissector. After docking, the dissection began at the psoas muscle and progressed proximally to expose further anatomical landmarks. This approach led to the identification of the ureter, followed by the inferior renal pole and hilum (Fig. 1). The rest of the procedure was typical of a PN. The artery and vessels were identified from the hilum, loops were placed, and the area was dissected to facilitate clamping. The renal mass was exposed, and the resection margin was marked. The artery was clamped using a bulldog clamp, and the mass was treated by enucleation or resection depending on its characteristics. Renorrhaphy was subsequently performed on the resection bed. Once the clamp was released, bleeding was checked and additional renorrhaphy was performed if necessary. Data Collection Data collected included demographics, preoperative, immediately postoperative, and postoperative 1 day hemoglobin (Hb) levels, estimated glomerular filtration rate (GFR), operative time, warm ischemic time, estimated blood loss (EBL), length of hospital stay (LOS), pathology score, pain score using the numeric rating scale on postoperative day 1, nephrometry score [12], and day of bowel function return. No statiscal analysis was performed. Results In this retrospective review, we analyzed 35 surgical cases between December 2023 and December 2024, with the majority being PNs (n = 25), followed by less frequent procedures such as nephroureterectomy, pyeloplasty, adrenalectomy, cyst excision, ureterectomy, and retroperitoneal mass excision. One patient simultaneously underwent PN and adrenalectomy at the same time. The overall patient demographics included 34 individuals with an average age of 60.3 ± 11.6 years, with a slightly higher proportion of males (n = 22) compared to females (n = 12) (Table 1 ). Table 1 Types of surgeries Types of surgeries, n 34 Partial nephrectomy, n (%) 25 (73.5) Nephroureterectomy, n (%) 1 (2.9) Pyeloplasty, n (%) 2 (5.9) Adrenalectomy, n (%) 2 (5.9) Cyst excision, n (%) 2 (5.9) Ureterectomy, n (%) 1 (2.9) Retroperitoneal mass excision, n (%) 1 (2.9) The average body mass index was 24.8 ± 3.2 across all surgical types, which indicated a generally healthy weight range in the cohort. Preoperative eGFR was 87.9 ± 13.7 mL/min, with perioperative and postoperative decreases of -7.7 ± 10.7 and − 3.6 ± 12.9 mL/min, respectively, reflecting the renal impact of surgeries. Hb levels remained stable preoperatively at 14.0 ± 1.4 g/dL with a minor reduction of -1.7 ± 0.9 g/dL postoperatively(Table 2 ). Table 2 Surgical outcomes Partial Nephrectomy All types of Surgeries Number of patients 25 34 Age at surgery 60.2 ± 11.9 60.3 ± 11.6 Sex Male 18 (72%) 22 (65%) Female 7 (28%) 12 (35%) BMI (kg/m 2 ) 25.0 ± 3.4 24.8 ± 3.2 Preoperative eGFR (mL/min) 89.5 ± 12.6 87.9 ± 13.7 Change in eGFR (immediate postoperative, mL/min) 1 -9.0 ± 11.6 -7.7 ± 10.7 Change in eGFR (postoperative, mL/min) 2 -5.3 ± 13.4 -3.6 ± 12.9 Preoperative Hb (g/dL) 14.0 ± 1.4 14.0 ± 1.4 Change in Hb (postoperative, g/dL) 3 -2.0 ± 0.8 -1.7 ± 0.9 Ischemia time (min) 21.3 ± 10.7 Operative time (min) 200.6 ± 79.6 203.1 ± 90.0 Console time (min) 137.8 ± 75.5 141.9 ± 88.5 EBL (mL) 366.6 ± 345.2 330.4 ± 333.7 Intraoperative transfusion, n (%) 1(4.0%) 0 LOS (days) 7.1 ± 1.4 6.9 ± 1.5 Postoperative pain score 2.4 ± 0.7 2.5 ± 0.7 Postoperative complications 0 0 Gas out (Postoperative day) 1.8 ± 0.7 1.7 ± 0.8 Positive surgical margins, n (%) 0 Tumor histopathology type, n (%) Clear 18 (72.0%) Papillary 4 (16.0%) AML 2 (8.0%) Others 1 (Oncocytoma) Tumor size (cm) 3.5 ± 1.9 Tumor location, n (%) UP 7 (28.0%) MP 11 (44.0%) LP 7 (28.0%) Clinical stage cT1a–b, n (%) 25 (100.0%) Nephrometry score (median) 7 Nephrometry score H, n (%) 4 (16.0%) BMI, body mass index; eGFR, estimated glomerular filtration rate; EBL, estimated blood loss; LOS, length of stay; Hb, hemoglobin; AML, angiomyolipoma; UP upper pole; MP, mid-pole; LP, lower pole of the kidney; H (hilum), tumors contacting the main renal artery or vein. 1 Change in eGFR (immediate postoperative) was calculated as: eGFR at post-anesthesia care unit minus preoperative eGFR 2 Change in eGFR (postoperative) was defined as: eGFR at discharge minus preoperative eGFR 3 Change in Hb was calculated as: postoperative hemoglobin minus preoperative hemoglobin The average surgery time was 203.1 ± 90.0 minutes, with the console time for robotic procedures averaging 141.9 ± 88.5 minutes. EBL was moderate at 330.4 ± 333.7 mL, highlighting the controlled surgical environment. Postoperative LOS in the hospital averaged 6.9 ± 1.5 days, demonstrating efficient recovery processes(Table 2 ). Pain management was effective, with a postoperative pain score averaging 2.5 ± 0.7, indicating well-controlled pain. Postoperative complications were minimal and no significant events were reported. Gastrointestinal recovery, as indicated by the average time to first flatus ('Gas out'), was 1.7 ± 0.8 days(Table 2 ). Focusing specifically on the 25 PN cases, the surgeries predominantly managed tumors localized to the mid-pole (MP, n = 11) of the kidney, with all patients staged between cT1a and cT1b. The average tumor size was 3.5 ± 1.9 cm. Histopathological analysis showed that the majority of tumors were of the clear cell type (n = 18), followed by papillary (n = 4) and angiomyolipomas (n = 2), with one case of oncocytoma. There were no conversions to open surgery, no postoperative major complications (Table 2 .) Discussion SARA has demonstrated its viability not only for masses located at the lower pole but also for those at the upper pole and for performing adrenalectomies. Among the 25 cases of PN analyzed, seven involved tumors at the upper pole and required an average of 149.7 minutes to complete, slightly longer than the 137.8 minutes for other locations, yet proving entirely feasible. Additionally, two successful adrenalectomies highlighted the versatility of the approach, with one involving a 4.5-cm adrenal mass on the right side and the other concurrent with a left PN. The incision site can be modified depending on the location of the target area, with upper pole masses or adrenal lesions being higher and lower ureter lesions being lower, thus proving the versatility of this approach. Surgeries typically begin with the identification of the psoas muscle as a landmark, followed by tracing the ureter to locate the pedicle, which is beneficial for procedures such as pyeloplasty and ureterectomy due to early identification of the ureter. One challenge was accessibility in patients with high body fat, although surgery was still achievable. For instance, a left PN in a patient with a body mass index of 32.71 was completed in 91 min of console time and 170 min overall. Surgeons new to the SARA technique may face challenges with orientation, with initially longer console times. An outlier case involved excessive blood loss (1,500 mL) and extended times due to equipment issues during clamping. Excluding this outlier, the results were considered reliable, and a supplementary table excluding the outlier is attached (Supplement Table 1 ). The supine retroperitoneal approach inherently offers many advantages over the decubitus position and transperitoneal approach. It does not invade the peritoneal cavity, thus reducing the potential damage to intra-abdominal organs and lowering the risk of complications such as adhesions, peritonitis, or intestinal damage. The SARA technique contributes to faster postoperative recovery and shorter hospital stay owing to reduced manipulation of intra-abdominal structures, leading to a quicker return of bowel function and less pain [ 10 , 11 ]. For patients with a history of abdominal surgery or those who have a ‘hostile abdomen,’ the retroperitoneal approach is considered a safer alternative as it avoids intra-abdominal adhesions sites. It has been successfully used in various urological procedures and is particularly suitable for the treatment of posterior kidney lesions [ 12 ]. Moreover, due to the confined space of the retroperitoneum, complications such as urinary leakage or infections are locally confined, leading to safer outcomes [ 13 ]. Despite these advantages, the integration of multiport robotic surgery into the retroperitoneal space has not been fully realized, largely because of the bulky frame of the robotic platform. This, combined with the narrow confines of the retroperitoneum, results in poor instrument triangulation and frequent external clashing of instruments [ 10 ]. Lateral decubitus positioning, widely used in various urological procedures for adequate surgical exposure, can lead to distinct complications. These include ophthalmological, musculoskeletal, neurovascular, and hemodynamic issues [ 14 – 18 ]. In contrast, the supine position provides greater stability and maintains all anatomical structures in a neutral alignment, facilitating adequate respiratory function and enhancing patient safety on the surgical table [ 19 , 20 ]. Limitations In this study, we did not perform a statistical comparison with conventional retroperitoneal organ surgery. Once a sufficient number of cases have been accumulated, performing a statistical comparison of surgical outcomes would be beneficial. The da Vinci SP robot and supine anterior retroperitoneal approach are not necessary for all surgeries but represent an additional tool that can be advantageous in specific situations. Such studies could help define the indications for SARA and facilitate more appropriate case selection. Moreover, further investigations are warranted to determine the number of cases required to overcome the learning curve and perform statistical comparisons with traditional methods. Conclusion The supine anterior retroperitoneal approach with a robotic SP for PN and retroperitoneal organ procedures is feasible and promising, with the potential to enhance benefits related to positioning and approach methods. Future studies are warranted to define clear indications for SARA, compare outcomes with conventional approaches through prospective trials, and determine the learning curve based on cumulative case volume. Abbreviations EBL estimated blood loss eGFR estimated glomerular filtration rate Hb hemoglobin LOS length of stay PN partial nephrectomy SP single port SARA supine anterior retroperitoneal access Declarations Ethics approval and consent to participate This study was approved by the Institutional Review Board of Seoul National University Seoul Metropolitan Government Boramae Medical Center (IRB No. 40-2025-4). The requirement for informed consent was waived by the same ethics committee due to the retrospective nature of the study. The study was conducted in accordance with the Declaration of Helsinki. Consent for publication Not applicable. Competing interests The authors declare that they have no competing interests. Funding This study received no external funding. Author Contribution HB and SHC contributed to the study design, data analysis, and manuscript writing. JHY and SCK collected and organized the patient data. TK and SP provided critical revision and interpretation of the results. SHC supervised the study as the corresponding author. All authors read and approved the final manuscript. Acknowledgement The authors thank the surgical nursing and administrative staff at Ulsan University Hospital for their assistance during the procedures and data collection. Data Availability The datasets generated and during the current study are available from the corresponding author and the first author on reasonable request. References Zeuschner P, Siemer S. [Robot-assisted surgery for renal cell carcinoma - today a standard?]. Aktuelle Urol. 2021;52(5):464–73. Bahler CD, Monn MF, Flack CK, Gramm AR, Gardner TA, Sundaram CP. Assessing Cost of Robotic Utilization in Partial Nephrectomy with Increasing Utilization. J Endourol. 2018;32(8):710–6. BJabaji R, HeidiFischer, TylerKern WCG. Trend of Surgical Treatment of Localized Renal Cell Carcinoma. Permanente J. 2019;23(1):18–108. Kim KH, Ahn HK, Kim M, Yoon H. Technique and perioperative outcomes of single-port robotic surgery using the da Vinci SP platform in urology. Asian J Surg. 2023;46(1):472–7. Palacios AR, Morgantini L, Trippel R, Crivellaro S, Abern MR. Comparison of Perioperative Outcomes Between Retroperitoneal Single-Port and Multiport Robot-Assisted Partial Nephrectomies. J Endourol. 2022;36(12):1545–50. Raver M, Ahmed M, Okhawere KE, Saini I, Chaturvedi R, Patel M, et al. Adoption of Single-Port Robotic Partial Nephrectomy Increases Utilization of the Retroperitoneal Approach: A Report from the Single-Port Advanced Research Consortium. J Laparoendosc Adv Surg Tech. 2025;35(2):131–7. Cannoletta D, Pellegrino AA, Pettenuzzo G, Morgantini L, Calvo RS, Torres-Anguiano JR, et al. Surgical outcomes of novel retroperitoneal low anterior vs posterior and transperitoneal access in single-port partial nephrectomy. World J Urol. 2024;42(1):387. Omidele O, Elkun Y, Connors C, Eraky A, Mehrazin R. Narrative Review of Single-Port Surgery in Genitourinary Cancers. Cancers (Basel). 2025;17(3). Razdan S, Okhawere KE, Zuluaga L, Saini I, Ucpinar B, Sauer RC, et al. Comparison of lateral flank approach and low anterior access for single port (SP) retroperitoneal partial nephrectomy: an analysis from the single port advanced research consortium (SPARC). J Robotic Surg. 2024;18(1):216. Pellegrino AA, Chen G, Morgantini L, Calvo RS, Crivellaro S. Simplifying Retroperitoneal Robotic Single-port Surgery: Novel Supine Anterior Retroperitoneal Access. Eur Urol. 2023;84(2):223–8. Bang S, Yu J, Bae H, Shin D, Park YH, Cho HJ, et al. Single-Port Versus Multi-Port Robotic Retroperitoneal Partial Nephrectomy: A Propensity Score-Matched Comparison. J Endourol. 2024;38(12):1353–8. Kutikov A, Uzzo RG. The R.E.N.A.L. nephrometry score: a comprehensive standardized system for quantitating renal tumor size, location and depth. J Urol. 2009;182(3):844–53. Srivastava A, Sureka SK, Vashishtha S, Agarwal S, Ansari MS, Kumar M. Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve. J Minim Access Surg. 2016;12(2):102–8. Zhang AS, Osorio C, Stone BK, Hong J, Alsoof D, McDonald CL, et al. Complications of Lateral Decubitus Positioning During Orthopaedic Surgery. JBJS Reviews. 2023;11(6):e2300013. Dhansura T, Kapadia S, Kapadia D. Lateral position… beware! J Anaesthesiol Clin Pharmacol. 2016;32(4):535–6. Thakare A, Singhai A, Wakode S, Hulke S, Malhotra V, Issac S, et al. Changes in Peripheral Brachial Blood Pressure from Supine to Lateral Decubitus Position in Hypertensive and Normotensive Subjects. Mymensingh Med J. 2023;32(1):240–6. Saraswat V. Effects of anaesthesia techniques and drugs on pulmonary function. Indian J Anaesth. 2015;59(9):557–64. Ren D, Zhang B, Xu J, Liu R, Wang J, Huo H et al. Effect of Upper Arm Position Changes on the Occurrence of Ipsilateral Shoulder Pain After Single-Operator Port Thoracoscopy. Front Surg. 2022;9. Guideline for positioning the patient. AORN J. 2017;105(4):P8–10. Wang N, Chai N, Li L, Bi Y, Liu S, Zhang W, et al. Safety and Efficacy of the Supine Position with the Right Shoulder Raised versus the Left Lateral Position in Peroral Endoscopic Myotomy for Achalasia: A Large-Sample Retrospective Study. Gastroenterol Res Pract. 2022;2022:3202212. Additional Declarations No competing interests reported. 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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-6926946","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":481211189,"identity":"44d4bb45-b726-4b61-bb39-22587f7f4177","order_by":0,"name":"Hoyoung Bae","email":"","orcid":"","institution":"Seoul National University Seoul Metropolitan Government Boramae Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Hoyoung","middleName":"","lastName":"Bae","suffix":""},{"id":481211190,"identity":"0ca31b0d-1dc6-46fc-92c6-14f8e8f71d0a","order_by":1,"name":"Ji Hyung Yoon","email":"","orcid":"","institution":"Ulsan University Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ji","middleName":"Hyung","lastName":"Yoon","suffix":""},{"id":481211191,"identity":"eba69b2b-b113-45bb-a973-fe05a9eb9af4","order_by":2,"name":"Seong Cheol Kim","email":"","orcid":"","institution":"Ulsan University Hospital","correspondingAuthor":false,"prefix":"","firstName":"Seong","middleName":"Cheol","lastName":"Kim","suffix":""},{"id":481211192,"identity":"b98b7da5-8aa6-469e-8ddd-04fea8c30b4d","order_by":3,"name":"Taekmin Kwon","email":"","orcid":"","institution":"Ulsan University Hospital","correspondingAuthor":false,"prefix":"","firstName":"Taekmin","middleName":"","lastName":"Kwon","suffix":""},{"id":481211193,"identity":"0713f3f7-5775-45d7-a34a-c4d7cd5501c9","order_by":4,"name":"Sungchan Park","email":"","orcid":"","institution":"Ulsan University Hospital","correspondingAuthor":false,"prefix":"","firstName":"Sungchan","middleName":"","lastName":"Park","suffix":""},{"id":481211194,"identity":"50668883-21ca-439c-b0e2-4201c212700a","order_by":5,"name":"Sang Hyeon Cheon","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0ElEQVRIie3OoQ7CMBCA4WuWTHVgtyyMVyhB8jJMYZETEyVLhiG8wAjPMAwE1+aSYQpPgACDBkOmCIMJHB0O0d9cTny5AzCZ/jKLQxQBMAAiXrurJ4SDUm8CP5B9+gtpZ3JykksMN0CZLOMjeJn4TtxDmDC5xnDLKUNaXMBvDTVnFEn9W0VyURGwEQKqEV1FpqVc1ESWjwaEVVdA8poIJ0XwdaSnSOKKYtTP0R6jM0fqzTQkUJa8injQyXfJ6lzeMXCVhnyy6qF7y2QymUxNegKPFUnrN+M1eQAAAABJRU5ErkJggg==","orcid":"","institution":"Ulsan University Hospital","correspondingAuthor":true,"prefix":"","firstName":"Sang","middleName":"Hyeon","lastName":"Cheon","suffix":""}],"badges":[],"createdAt":"2025-06-19 03:08:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6926946/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6926946/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":86141150,"identity":"5661f36f-a1b0-441f-8b54-dd424d7129fd","added_by":"auto","created_at":"2025-07-07 08:24:25","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1319246,"visible":true,"origin":"","legend":"\u003cp\u003eSurgical Steps for Performing Partial Nephrectomy via Supine Anterior Retroperitoneal Access (SARA)\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6926946/v1/cdbb5ec80b511b4b0bb9bca0.jpeg"},{"id":90967083,"identity":"7a159b29-3ad4-4901-910a-2d00d7e8ec40","added_by":"auto","created_at":"2025-09-10 06:47:12","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1879452,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6926946/v1/edfc8221-1c27-4b76-bc20-f5c0b77152ee.pdf"},{"id":86141146,"identity":"1b1e8b7a-11e0-44a4-b16e-613d3abd0e67","added_by":"auto","created_at":"2025-07-07 08:24:25","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":19230,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementTable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6926946/v1/086d9eb0163529fd486c73b7.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Initial Experience of Partial Nephrectomy and Retroperitoneal Organ Surgery using Supine Anterior Retroperitoneal Access (SARA) with the da Vinci SP Robotic System: Initial descriptive analysis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn 2021, the incidence of kidney cancer in South Korea was reported \u0026nbsp; 6,883, accounting for 2.5% of all cancer incidence and ranking tenth overall. The 5-year relative survival rate for kidney cancer has significantly improved from 64.2% during 1993-1995 to 86.4% in 2017-2021. This improvement can be largely attributed to advancements in robotic surgery [1].\u003c/p\u003e\n\u003cp\u003eIn the United States, the proportion of robot-assisted partial nephrectomies (PNs) among all PNs increased from 20% to 49% between 2009 and 2012 [2]. After FDA approval of robot-assisted laparoscopic PN in 2011, this technique quickly became more prevalent than either laparoscopic PN or laparoscopic radical nephrectomy, surpassing them in 2012 and 2014, respectively [3].\u003c/p\u003e\n\u003cp\u003eIntroduction of the da Vinci Single-Port (SP) system in 2018 marked a significant milestone in the development of minimally invasive surgery. This system, featuring a single 2.5-cm cannula for the insertion of a camera and three robotic arms, offers a less invasive approach than conventional multiport robotic platforms. This technological advancement is particularly beneficial in confined surgical spaces such as the retroperitoneum, enhancing instrument triangulation and dexterity [4,5]. The da Vinci SP system also enables targeting of specific anatomy during a procedure without compromising the less relevant surrounding structures, thus realizing the concept of “regionalization”. Following its introduction, there was a significant increase in the adoption of the retroperitoneal approach, with its usage increasing from 7.3% to 24.8% in a consortium of 12 institutions [6].\u003c/p\u003e\n\u003cp\u003eThe supine anterior retroperitoneal access (SARA) is a minimally invasive surgical approach that enables direct anterior access to retroperitoneal organs, including the kidney and adrenal gland, with the patient in the supine position. Unlike conventional lateral decubitus retroperitoneal approaches, SARA utilizes anterior anatomical landmarks such as the psoas muscle and peritoneal reflection to develop the retroperitoneal space. This positioning improves ergonomics, facilitates simultaneous bilateral access if needed, and minimizes patient repositioning time. Since its first introduction by Pellegrino et al. in 2022, SARA has demonstrated feasibility in various retroperitoneal surgeries, such as partial nephrectomy, adrenalectomy, and lymph node dissection, and continues to expand its clinical indications.\u003c/p\u003e\n\u003cp\u003eWhile some studies have referred to similar approaches as the low anterior approach (LAA), these were not exclusively performed in the supine position but involved both the decubitus and supine positions [7-9]. Therefore, supine anterior retroperitoneal access (SARA), first introduced and utilized by Pellegrino et al. is considered more appropriate in this context [10].\u003c/p\u003e\n\u003cp\u003eIn South Korea, the use of da Vinci SP robots for retroperitoneal PNs has become increasingly common. Bang et al. reported 44 cases of PN using a da Vinci SP robot via a retroperitoneal approach; however, these procedures were performed in the lateral decubitus position [11].\u003c/p\u003e\n\u003cp\u003eIn this paper, we describe our initial experiences and perioperative outcomes using this novel SARA technique with da Vinci SP robots, aiming to provide a safer, more efficient, and consistently reproducible method for 25 cases of PN, but also 9 cases of retroperitoneal organ surgery.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eAll surgical procedures were performed at a tertiary hospital by an expert surgeon from December 27, 2023, to December 18, 2024, using the da Vinci SP robotic system (Intuitive, Sunnyvale, CA, USA). This study was approved by the Institutional Review Board of a secondary medical center run by a university (approval number: 40-2025-4)\u0026nbsp;and the requirement for informed consent was waived due to the retrospective nature of the study.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSurgical Technique\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe patient was placed in the supine position and a 3-cm vertical incision was made approximately two-thirds laterally along the line from the umbilicus to the anterior superior iliac spine. The subcutaneous tissue was dissected, and the aponeurosis of the external oblique muscle was incised, after which the three muscle layers were bluntly separated. By finger dissection, the retroperitoneal space was prepared for the da Vinci SP access port (Intuitive, Sunnyvale, CA, USA), and a 12-mm AirSeal assistant port (ConMed Corp., Utica, NY, USA) was inserted in the lower part of the incision in a “sidecar” fashion. An AirSeal insufflation system (ConMed Corp., Utica, NY, USA) was used to maintain an insufflation pressure of 12 mmHg.\u003c/p\u003e\n\u003cp\u003eGas insufflation secures the retroperitoneal space without a balloon dissector. After docking, the dissection began at the psoas muscle and progressed proximally to expose further anatomical landmarks. This approach led to the identification of the ureter, followed by the inferior renal pole and hilum (Fig. 1). The rest of the procedure was typical of a PN. The artery and vessels were identified from the hilum, loops were placed, and the area was dissected to facilitate clamping. The renal mass was exposed, and the resection margin was marked. The artery was clamped using a bulldog clamp, and the mass was treated by enucleation or resection depending on its characteristics. Renorrhaphy was subsequently performed on the resection bed. Once the clamp was released, bleeding was checked and additional renorrhaphy was performed if necessary.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eData Collection\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eData collected included demographics, preoperative, immediately postoperative, and postoperative 1 day hemoglobin (Hb) levels, estimated glomerular filtration rate (GFR), operative time, warm ischemic time, estimated blood loss (EBL), length of hospital stay (LOS), pathology score, pain score using the numeric rating scale on postoperative day 1, nephrometry score [12], and day of bowel function return. No statiscal analysis was performed.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn this retrospective review, we analyzed 35 surgical cases between December 2023 and December 2024, with the majority being PNs (n\u0026thinsp;=\u0026thinsp;25), followed by less frequent procedures such as nephroureterectomy, pyeloplasty, adrenalectomy, cyst excision, ureterectomy, and retroperitoneal mass excision. One patient simultaneously underwent PN and adrenalectomy at the same time. The overall patient demographics included 34 individuals with an average age of 60.3\u0026thinsp;\u0026plusmn;\u0026thinsp;11.6 years, with a slightly higher proportion of males (n\u0026thinsp;=\u0026thinsp;22) compared to females (n\u0026thinsp;=\u0026thinsp;12) (Table\u0026nbsp;\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\u003eTypes of surgeries\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTypes of surgeries, n\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePartial nephrectomy, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25 (73.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNephroureterectomy, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePyeloplasty, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2 (5.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAdrenalectomy, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2 (5.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCyst excision, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2 (5.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUreterectomy, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRetroperitoneal mass excision, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.9)\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\u003eThe average body mass index was 24.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2 across all surgical types, which indicated a generally healthy weight range in the cohort. Preoperative eGFR was 87.9\u0026thinsp;\u0026plusmn;\u0026thinsp;13.7 mL/min, with perioperative and postoperative decreases of -7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;10.7 and \u0026minus;\u0026thinsp;3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;12.9 mL/min, respectively, reflecting the renal impact of surgeries. Hb levels remained stable preoperatively at 14.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4 g/dL with a minor reduction of -1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9 g/dL postoperatively(Table\u0026nbsp;\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\u003eSurgical outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\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=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePartial Nephrectomy\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAll types of Surgeries\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNumber of patients\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"9\" rowspan=\"10\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge at surgery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e60.2\u0026thinsp;\u0026plusmn;\u0026thinsp;11.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e60.3\u0026thinsp;\u0026plusmn;\u0026thinsp;11.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSex\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18 (72%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22 (65%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7 (28%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12 (35%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e24.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreoperative eGFR (mL/min)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e89.5\u0026thinsp;\u0026plusmn;\u0026thinsp;12.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e87.9\u0026thinsp;\u0026plusmn;\u0026thinsp;13.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChange in eGFR\u003c/p\u003e\u003cp\u003e(immediate postoperative, mL/min)\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;11.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-7.7\u0026thinsp;\u0026plusmn;\u0026thinsp;10.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChange in eGFR (postoperative, mL/min)\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;13.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;12.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreoperative Hb (g/dL)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e14.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eChange in Hb (postoperative, g/dL)\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIschemia time (min)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e21.3\u0026thinsp;\u0026plusmn;\u0026thinsp;10.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"8\" rowspan=\"9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOperative time (min)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e200.6\u0026thinsp;\u0026plusmn;\u0026thinsp;79.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e203.1\u0026thinsp;\u0026plusmn;\u0026thinsp;90.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eConsole time (min)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e137.8\u0026thinsp;\u0026plusmn;\u0026thinsp;75.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e141.9\u0026thinsp;\u0026plusmn;\u0026thinsp;88.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEBL (mL)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e366.6\u0026thinsp;\u0026plusmn;\u0026thinsp;345.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e330.4\u0026thinsp;\u0026plusmn;\u0026thinsp;333.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntraoperative transfusion, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1(4.0%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLOS (days)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePostoperative pain score\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePostoperative complications\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGas out (Postoperative day)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePositive surgical margins, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"11\" rowspan=\"12\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\" morerows=\"11\" rowspan=\"12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e\u003cp\u003eTumor histopathology type, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eClear\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18 (72.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePapillary\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4 (16.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAML\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2 (8.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOthers\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1 (Oncocytoma)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTumor size (cm)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eTumor location, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7 (28.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11 (44.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7 (28.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eClinical stage cT1a\u0026ndash;b, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25 (100.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNephrometry score (median)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNephrometry score H, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4 (16.0%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eBMI, body mass index; eGFR, estimated glomerular filtration rate; EBL, estimated blood loss; LOS, length of stay; Hb, hemoglobin; AML, angiomyolipoma; UP upper pole; MP, mid-pole; LP, lower pole of the kidney; H (hilum), tumors contacting the main renal artery or vein.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e1\u003c/sup\u003eChange in eGFR (immediate postoperative) was calculated as: eGFR at post-anesthesia care unit minus preoperative eGFR\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e2\u003c/sup\u003eChange in eGFR (postoperative) was defined as: eGFR at discharge minus preoperative eGFR\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e3\u003c/sup\u003eChange in Hb was calculated as: postoperative hemoglobin minus preoperative hemoglobin\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe average surgery time was 203.1\u0026thinsp;\u0026plusmn;\u0026thinsp;90.0 minutes, with the console time for robotic procedures averaging 141.9\u0026thinsp;\u0026plusmn;\u0026thinsp;88.5 minutes. EBL was moderate at 330.4\u0026thinsp;\u0026plusmn;\u0026thinsp;333.7 mL, highlighting the controlled surgical environment. Postoperative LOS in the hospital averaged 6.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5 days, demonstrating efficient recovery processes(Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003ePain management was effective, with a postoperative pain score averaging 2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7, indicating well-controlled pain. Postoperative complications were minimal and no significant events were reported. Gastrointestinal recovery, as indicated by the average time to first flatus ('Gas out'), was 1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8 days(Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eFocusing specifically on the 25 PN cases, the surgeries predominantly managed tumors localized to the mid-pole (MP, n\u0026thinsp;=\u0026thinsp;11) of the kidney, with all patients staged between cT1a and cT1b. The average tumor size was 3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9 cm. Histopathological analysis showed that the majority of tumors were of the clear cell type (n\u0026thinsp;=\u0026thinsp;18), followed by papillary (n\u0026thinsp;=\u0026thinsp;4) and angiomyolipomas (n\u0026thinsp;=\u0026thinsp;2), with one case of oncocytoma.\u003c/p\u003e\u003cp\u003eThere were no conversions to open surgery, no postoperative major complications (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.)\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSARA has demonstrated its viability not only for masses located at the lower pole but also for those at the upper pole and for performing adrenalectomies. Among the 25 cases of PN analyzed, seven involved tumors at the upper pole and required an average of 149.7 minutes to complete, slightly longer than the 137.8 minutes for other locations, yet proving entirely feasible. Additionally, two successful adrenalectomies highlighted the versatility of the approach, with one involving a 4.5-cm adrenal mass on the right side and the other concurrent with a left PN. The incision site can be modified depending on the location of the target area, with upper pole masses or adrenal lesions being higher and lower ureter lesions being lower, thus proving the versatility of this approach.\u003c/p\u003e\u003cp\u003eSurgeries typically begin with the identification of the psoas muscle as a landmark, followed by tracing the ureter to locate the pedicle, which is beneficial for procedures such as pyeloplasty and ureterectomy due to early identification of the ureter. One challenge was accessibility in patients with high body fat, although surgery was still achievable. For instance, a left PN in a patient with a body mass index of 32.71 was completed in 91 min of console time and 170 min overall.\u003c/p\u003e\u003cp\u003eSurgeons new to the SARA technique may face challenges with orientation, with initially longer console times. An outlier case involved excessive blood loss (1,500 mL) and extended times due to equipment issues during clamping. Excluding this outlier, the results were considered reliable, and a supplementary table excluding the outlier is attached (Supplement Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe supine retroperitoneal approach inherently offers many advantages over the decubitus position and transperitoneal approach. It does not invade the peritoneal cavity, thus reducing the potential damage to intra-abdominal organs and lowering the risk of complications such as adhesions, peritonitis, or intestinal damage. The SARA technique contributes to faster postoperative recovery and shorter hospital stay owing to reduced manipulation of intra-abdominal structures, leading to a quicker return of bowel function and less pain [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. For patients with a history of abdominal surgery or those who have a \u0026lsquo;hostile abdomen,\u0026rsquo; the retroperitoneal approach is considered a safer alternative as it avoids intra-abdominal adhesions sites. It has been successfully used in various urological procedures and is particularly suitable for the treatment of posterior kidney lesions [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Moreover, due to the confined space of the retroperitoneum, complications such as urinary leakage or infections are locally confined, leading to safer outcomes [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDespite these advantages, the integration of multiport robotic surgery into the retroperitoneal space has not been fully realized, largely because of the bulky frame of the robotic platform. This, combined with the narrow confines of the retroperitoneum, results in poor instrument triangulation and frequent external clashing of instruments [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eLateral decubitus positioning, widely used in various urological procedures for adequate surgical exposure, can lead to distinct complications. These include ophthalmological, musculoskeletal, neurovascular, and hemodynamic issues [\u003cspan additionalcitationids=\"CR15 CR16 CR17\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In contrast, the supine position provides greater stability and maintains all anatomical structures in a neutral alignment, facilitating adequate respiratory function and enhancing patient safety on the surgical table [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cb\u003eLimitations\u003c/b\u003e\u003c/p\u003e\u003cp\u003eIn this study, we did not perform a statistical comparison with conventional retroperitoneal organ surgery. Once a sufficient number of cases have been accumulated, performing a statistical comparison of surgical outcomes would be beneficial.\u003c/p\u003e\u003cp\u003eThe da Vinci SP robot and supine anterior retroperitoneal approach are not necessary for all surgeries but represent an additional tool that can be advantageous in specific situations. Such studies could help define the indications for SARA and facilitate more appropriate case selection.\u003c/p\u003e\u003cp\u003eMoreover, further investigations are warranted to determine the number of cases required to overcome the learning curve and perform statistical comparisons with traditional methods.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe supine anterior retroperitoneal approach with a robotic SP for PN and retroperitoneal organ procedures is feasible and promising, with the potential to enhance benefits related to positioning and approach methods.\u003c/p\u003e\u003cp\u003eFuture studies are warranted to define clear indications for SARA, compare outcomes with conventional approaches through prospective trials, and determine the learning curve based on cumulative case volume.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eEBL\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eestimated blood loss\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eeGFR\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eestimated glomerular filtration rate\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eHb\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ehemoglobin\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eLOS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003elength of stay\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003ePN\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003epartial nephrectomy\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eSP\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003esingle port\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eSARA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003esupine anterior retroperitoneal access\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e\u003cp\u003e This study was approved by the Institutional Review Board of Seoul National University Seoul Metropolitan Government Boramae Medical Center (IRB No. 40-2025-4). The requirement for informed consent was waived by the same ethics committee due to the retrospective nature of the study. The study was conducted in accordance with the Declaration of Helsinki.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cp\u003eNot applicable.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eCompeting interests\u003c/h2\u003e\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eThis study received no external funding.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eHB and SHC contributed to the study design, data analysis, and manuscript writing. JHY and SCK collected and organized the patient data. TK and SP provided critical revision and interpretation of the results. SHC supervised the study as the corresponding author. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors thank the surgical nursing and administrative staff at Ulsan University Hospital for their assistance during the procedures and data collection.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets generated and during the current study are available from the corresponding author and the first author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eZeuschner P, Siemer S. [Robot-assisted surgery for renal cell carcinoma - today a standard?]. Aktuelle Urol. 2021;52(5):464\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBahler CD, Monn MF, Flack CK, Gramm AR, Gardner TA, Sundaram CP. Assessing Cost of Robotic Utilization in Partial Nephrectomy with Increasing Utilization. J Endourol. 2018;32(8):710\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBJabaji R, HeidiFischer, TylerKern WCG. Trend of Surgical Treatment of Localized Renal Cell Carcinoma. Permanente J. 2019;23(1):18\u0026ndash;108.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKim KH, Ahn HK, Kim M, Yoon H. Technique and perioperative outcomes of single-port robotic surgery using the da Vinci SP platform in urology. Asian J Surg. 2023;46(1):472\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePalacios AR, Morgantini L, Trippel R, Crivellaro S, Abern MR. Comparison of Perioperative Outcomes Between Retroperitoneal Single-Port and Multiport Robot-Assisted Partial Nephrectomies. J Endourol. 2022;36(12):1545\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRaver M, Ahmed M, Okhawere KE, Saini I, Chaturvedi R, Patel M, et al. Adoption of Single-Port Robotic Partial Nephrectomy Increases Utilization of the Retroperitoneal Approach: A Report from the Single-Port Advanced Research Consortium. J Laparoendosc Adv Surg Tech. 2025;35(2):131\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCannoletta D, Pellegrino AA, Pettenuzzo G, Morgantini L, Calvo RS, Torres-Anguiano JR, et al. Surgical outcomes of novel retroperitoneal low anterior vs posterior and transperitoneal access in single-port partial nephrectomy. World J Urol. 2024;42(1):387.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOmidele O, Elkun Y, Connors C, Eraky A, Mehrazin R. Narrative Review of Single-Port Surgery in Genitourinary Cancers. Cancers (Basel). 2025;17(3).\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRazdan S, Okhawere KE, Zuluaga L, Saini I, Ucpinar B, Sauer RC, et al. Comparison of lateral flank approach and low anterior access for single port (SP) retroperitoneal partial nephrectomy: an analysis from the single port advanced research consortium (SPARC). J Robotic Surg. 2024;18(1):216.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePellegrino AA, Chen G, Morgantini L, Calvo RS, Crivellaro S. Simplifying Retroperitoneal Robotic Single-port Surgery: Novel Supine Anterior Retroperitoneal Access. Eur Urol. 2023;84(2):223\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBang S, Yu J, Bae H, Shin D, Park YH, Cho HJ, et al. Single-Port Versus Multi-Port Robotic Retroperitoneal Partial Nephrectomy: A Propensity Score-Matched Comparison. J Endourol. 2024;38(12):1353\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKutikov A, Uzzo RG. The R.E.N.A.L. nephrometry score: a comprehensive standardized system for quantitating renal tumor size, location and depth. J Urol. 2009;182(3):844\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSrivastava A, Sureka SK, Vashishtha S, Agarwal S, Ansari MS, Kumar M. Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve. J Minim Access Surg. 2016;12(2):102\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhang AS, Osorio C, Stone BK, Hong J, Alsoof D, McDonald CL, et al. Complications of Lateral Decubitus Positioning During Orthopaedic Surgery. JBJS Reviews. 2023;11(6):e2300013.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDhansura T, Kapadia S, Kapadia D. Lateral position\u0026hellip; beware! J Anaesthesiol Clin Pharmacol. 2016;32(4):535\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eThakare A, Singhai A, Wakode S, Hulke S, Malhotra V, Issac S, et al. Changes in Peripheral Brachial Blood Pressure from Supine to Lateral Decubitus Position in Hypertensive and Normotensive Subjects. Mymensingh Med J. 2023;32(1):240\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSaraswat V. Effects of anaesthesia techniques and drugs on pulmonary function. Indian J Anaesth. 2015;59(9):557\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRen D, Zhang B, Xu J, Liu R, Wang J, Huo H et al. Effect of Upper Arm Position Changes on the Occurrence of Ipsilateral Shoulder Pain After Single-Operator Port Thoracoscopy. Front Surg. 2022;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGuideline for positioning the patient. AORN J. 2017;105(4):P8\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWang N, Chai N, Li L, Bi Y, Liu S, Zhang W, et al. Safety and Efficacy of the Supine Position with the Right Shoulder Raised versus the Left Lateral Position in Peroral Endoscopic Myotomy for Achalasia: A Large-Sample Retrospective Study. Gastroenterol Res Pract. 2022;2022:3202212.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"partial nephrectomy, supine anterior retroperitoneal access, retroperitoneal organ, adrenal","lastPublishedDoi":"10.21203/rs.3.rs-6926946/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6926946/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose:\u003c/strong\u003e This study aimed to describe the initial experience and perioperative outcomes of partial nephrectomy (PN) and other retroperitoneal organ surgeries using the supine anterior retroperitoneal access (SARA) technique with the da Vinci SP robotic system.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and Methods: \u003c/strong\u003eBetween December 2023 and December 2024, 35 retroperitoneal surgeries, including 25 PNs, were performed via SARA using a single-port robotic platform. The SARA approach utilizes anterior anatomical landmarks in the supine position to access retroperitoneal organs. Perioperative data, including operative time, warm ischemia time, estimated blood loss (EBL), postoperative renal function, length of stay (LOS), pain scores, and complications, were retrospectively reviewed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Among 34 patients (mean age 60.3 years), PN was the most common procedure (73.5%). The mean tumor size for PN was 3.5 cm, and all were staged cT1a–b. There were no conversions to open surgery, no positive margins, and no major complications. Mean operative time was 200.6 minutes, warm ischemia time 21.3 minutes, and EBL 366.6 mL. Postoperative LOS averaged 7.1 days, and pain scores were well controlled (mean 2.4). sCr and hemoglobin changes were within acceptable limits. The SARA technique was also successfully applied to adrenalectomy, ureterectomy, and retroperitoneal mass excisions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eSARA using the da Vinci SP platform is a feasible and safe approach for retroperitoneal surgeries, including PN and adrenalectomy. It offers advantages in patient positioning, surgical ergonomics, and recovery. Further studies are warranted to validate its role compared to traditional approaches and to define learning curve parameters.\u003c/p\u003e","manuscriptTitle":"Initial Experience of Partial Nephrectomy and Retroperitoneal Organ Surgery using Supine Anterior Retroperitoneal Access (SARA) with the da Vinci SP Robotic System: Initial descriptive analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-07 08:24:20","doi":"10.21203/rs.3.rs-6926946/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b3c90f23-e4f5-4580-989e-c3a7a7440fa5","owner":[],"postedDate":"July 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-10T06:39:05+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-07 08:24:20","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6926946","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6926946","identity":"rs-6926946","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}