Combination of the right hepatic vein occlusion and pringle maneuver in laparoscopic right posterior sectionectomy: protocol for a prospective non-randomized controlled study using propensity score-matched analysis

Combination of the right hepatic vein occlusion and pringle maneuver in laparoscopic right posterior sectionectomy: protocol for a prospective non-randomized controlled study using propensity score-matched 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 Study protocol Combination of the right hepatic vein occlusion and pringle maneuver in laparoscopic right posterior sectionectomy: protocol for a prospective non-randomized controlled study using propensity score-matched analysis Wugui Yang, Yufu Peng, Yubo Yang, Bin Liang, Bo Li, Yonggang Wei, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4727602/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 Introduction: Laparoscopic right posterior hepatectomy, particularly for standard anatomical resection, presents significant technical challenges. Achieving complete exposure of right hepatic vein (RHV) is the critical step in this procedure. To date, there is currently no universally accepted technique to ensure the safe exposure of RHV. To address this gap, this study designs a novel technique involving RHV occlusion and Pringle maneuver for enhancing the safety of RHV exposure in laparoscopic anatomical right posterior hepatectomy (LARPH). A comparative analysis between this innovative approach and traditional technique is performing to investigate the safety and efficacy of this innovative approach. Methods and analysis: This prospective non-randomized controlled trial is being conducted at West China Hospital and Sanya People’s Hospital. Patients undergoing LARPH using the novel technique (double occlusion) will be assigned to the experimental group, while those using the traditional technique (Pringle maneuver only) will be assigned to the control group. Perioperative outcomes and follow-up data will be collected and analyzed. PSM analysis with 1:1 ratio matching will be used to mitigate the potential selection deviation. The primary outcome is intraoperative blood loss. Secondary outcomes include the rate of successful RHV exposure, the incidence of CO 2 embolism, postoperative complications, as well as morbidity and mortality at 30 days and 90 days. Discussion In this study, the outflow occlusion of the target area is innovative adopted: the RHV is selectively occluded in LARPH to control the outflow of S67. Combined with the pringle maneuver, our technique potential has the benefits of reduced the risk of hemorrhage and CO 2 gas embolism. By developing and disseminating standardized protocols based on best practices and evidence from successful cases, this study aims to establish a safe, efficacy, and easily disseminated novel surgical technique. Trial registration: This study has been prospectively registered at Chinese Clinical Trial Registry ( https://www.chictr.org.cn/index.html ) on May 26, 2023. The identifier is ChiCTR2300071832 and the registry name is “Caudodorsal approach combined with the occlusion of the right hepatic vein and Pringle maneuver in laparoscopic right posterior sectionectomy”. Laparoscopic liver resection Anatomical resection Occlusion of right hepatic vein Pringle maneuver Double occlusion Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Continuous advancements in laparoscopic equipment and the establishment of a robust theoretical framework in minimal invasive surgery are contribute to the increasing application of laparoscopic techniques in the treatment of hepatic space-occupying lesions. The indications of laparoscopic liver resection covered a wide range of benign diseases, malignant tumors, and living donor liver transplantation [ 1 , 2 ]. Despite these improvements, laparoscopic right posterior hepatectomy is still a technically challenging procedure, particularly concerning anatomical resection [ 3 ]. The challenges faced by surgeons in laparoscopic anatomical right posterior hepatectomy (LARPH) could be attributed to the following two significant factors. Firstly, the deep location of the posterior area within the subcostal cavity limited the surgical visibility and operative space during surgery, causing increased difficulty and complexity in exposure, parenchymal transection, and hemostasis. Secondly, the right hepatic vein (RHV) was featured with thin vascular wall and numerous branches, which was vulnerable to injury during the exposing procedure. Meanwhile, because of the absence of the venous valve in RHV to prevent blood reflux from the inferior vena cava, the presence of venous perforations on the RHV carried an evaluated risk of hemorrhage, which has the potential to obscure the operative field or disorder the circulatory dynamics. Additionally, the carbon dioxide (CO 2 ) gas embolism may occur when CO 2 infiltrates into the bloodstream through venous perforations, leading to detrimental effects on respiration and circulation [ 4 , 5 ]. All these factors would contribute to an increased risk of conversion to open surgery and even lead to some potential life-threatening complications [ 6 ]. To enhance the practice of LARPH, several effective strategies have been reported in recent years. The caudate lobe‑first approach, proposed by Professor Honda, effectively simplified the exposure of the right posterior Glissonean pedicle by dividing of the caudate lobe [ 7 ]. This method facilitated a clearer surgical field and improved the precision of the procedure. Additionally, conducting parenchymal transection from the dorsal to ventral sides was aligned with the unique laparoscopic caudodorsal view and the anatomical features of the hepatic vein [ 8 , 9 ], which potentially mitigated the risk of RHV injury. Furthermore, the Pringle maneuver could effectively control the hepatic inflow by occluding hepatoduodenal ligament, which has been demonstrated the effect in reducing the blood loss during parenchymal transection [ 10 , 11 ]. Unfortunately, although these techniques have collectively contributed to the safe, efficient LARPH, they have yet to address the safe exposure of the right hepatic vein. In terms of anesthesia intervention, several studies demonstrated that a low central venous pressure (CVP) could reduce the risk of bleeding and emphasized the necessity of controlling low central venous pressure (CLCVP) for hepatic vein exposure [ 12 , 13 ]. However, managing CLCVP was technique demanding and involved potential risks of CO 2 gas embolism, acidosis, and acute kidney injury [ 14 – 16 ]. It is challenging to balance the risk of hemorrhage from the hepatic vein and the risk of CO 2 gas embolism from managing CLCVP, particularly in less experienced surgical centers. With regard to surgical technique, the adoption of a root-to-peripheral approach to expose RHV was hopeful in mitigating the risk of bifurcation injury [ 17 , 18 ]. However, this technique required a high degree of surgical expertise. Meanwhile, the injury of hepatic vein caused by anatomical variation, tissue traction, and unintentional incision was hard to avoid using this approach. Given these complexities, there is a pressing need for practical and widely accepted strategies to ensure the safe exposure of RHV. Herein, we propose an innovative technique of RHV occlusion aimed at ensuring safe exposure of RHV by interrupting the communication of RHV-IVC. This technique is designed to control the blood loss by preventing the blood reflux from IVC after hepatic inflow occlusion and to mitigate the risk of CO 2 gas embolism by preventing CO 2 into the bloodstream of IVC. Meanwhile, the Pringle maneuver will be adopted in this study to minimize intraoperative blood loss by controlling the hepatic inflow. Furthermore, the caudo-dorsal approach will be adopted to identify the target Glissonean pedicle and transecting the parenchyma in this study. This study will detail steps this novel technique for laparoscopic anatomical right posterior sectionectomy using the caudo-dorsal approach combined with double occlusion (RHV occlusion plus Pringle maneuver). The feasibility, safety, and efficacy of the double occlusion will be evaluated in this prospective study. Methods Study setting The study is a prospective non-randomized controlled trial aimed at evaluating the feasibility, safety, and efficacy of the double occlusion (RHV occlusion plus Pringle maneuver) in LARPH. This study will be conducted in two liver surgery centers: Division of Liver Surgery, Department of General Surgery, West China Hospital of Sichuan University, China; Department of General Surgery, Sanya People’s Hospital, China. Eligibility criteria This study will consecutively enroll eligible patients undergoing LARPH from May 2023 to December 2025. Patients undergoing LARPH using the novel technique (double occlusion) will be assigned to the experimental group, while those undergoing LARPH by using the traditional technique (Pringle maneuver only) will be assigned to the control group. Surgical strategies for all patients will be formulated and acquired consensus by three experienced surgeons. And patient will be matched in both groups on a 1:1 basis propensity score matching (PSM) to mitigate the potential selection bias (Fig. 1 ). Inclusion criteria (1) Patients aged 18 to 80 years old, inclusive of both males and females; (2) Patients eligible for general anesthesia or laparoscopic hepatectomy without contraindications; (3) Liver function classified as Child-Pugh A, with Indocyanine green (ICG) clearance test showing a retention ratio after 15 minutes < 15% [ 19 ]; (4) Diagnosis of liver malignant tumor, which included hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), combined HCC-ICC, or liver metastasis. (5) Tumor diameter ≤ 5 cm, without invasion over liver capsule or diaphragm; (6) Suitability for LARPH (S7 and S67) confirmed by a feasibility evaluation conducted by three experienced hepatobiliary pancreatic (HBP) experts, with an expected incision margin ≥ 1cm. Exclusion criteria (1) Patients with previous upper-abdominal surgery history; (2) Presence of cancer embolus in the main trunk of portal vein, bile duct, or RHV; (3) LARPH performed with other organs resection (except for gallbladder); (4) LARPH performed with additional segments resection or performed with radiofrequency ablation. Intervention Pre-operative assessment A comprehensive preoperative assessment will be conducted for all patients. The blood tests include complete blood count, liver and renal function tests, coagulation profile evaluation, serum alpha-fetoprotein (AFP) level, Protein Induced by Vitamin K Absence or Antagonist II (PIVKA II) level, and hepatitis B and C serology screening. Liver function will be assessed using the Child-Pugh grading system and the ICG-15 clearance test. Tumor characteristics including size, number, and location will be assessed through following imaging examinations: abdominal enhanced computed tomography (CT), contrast-enhanced ultrasonography (CEUS), or Magnetic Resonance Imaging (MRI). Patient's performance status will be recorded according to Eastern Cooperative Oncology Group (ECOG) criteria [ 20 ] and the American Society of Anesthesiologists physical status [ 21 ]. Additionally, chest CT scan will be utilized to evaluate pulmonary comorbidities. Surgical technique General steps The patient will be placed in the left 30 º trunk rotation Trendelenburg position. Five trocars will be inserted into the upper abdomen as follows: one optical trocar (10 mm), two main operating trocars (12 mm) and two assistant trocars (5 mm). And the pneumoperitoneum will be established with CO 2 and the intraperitoneal pressure will maintain 12–14 mmHg. A 30° laparoscope will provide a flexible view during this procedure. The caudo-dorsal approach combined with the occlusion of the RHV and Pringle maneuver (1) The right liver will be fully mobilized by dissecting perihepatic ligaments, allowing it to be uplifted and rotated towards the left side. Makuuchi ligament will be divided then to gain access to the secondary porta of the liver. The RHV will be isolated by dissecting the secondary porta from both the caudal and cranial sides. Extrahepatic suspension of RHV will be performed using an endo-retractor with a string (Fig. 2 ). (2) The caudate lobe first approach will be adopted to access and identify the target Glissonean pedicle (G7 or G67). For the exposure of G7, the caudate lobe will be transected along the midline in parallel with the ventral central line of the IVC. This is followed by detaching the caudate process from the posterior Glissonean pedicle. Then the G7 will be identified [ 22 ]. Theoretically, the G67 crosses over the border between the right posterior section and the caudate lobe. Therefore, the G67 could be isolated by dividing the caudate lobe. After identifying the ventral aspect of G67, the dorsal aspect of G67 will be exposed by dividing the caudate lobe along the rightmost line of the IVC between the right Glissonean pedicle and IVC [ 7 ]. The target pedicle is divided and the ischemic demarcation of its portal territory will be outlined on the liver surface (Fig. 3 ). (3) The pringle maneuver will be prepared and applied intermittently during parenchymal transection (15 min hepatic inflow occlusion with 5 min release for one cycle). The root of RHV will be clamped extrahepatic by a Bulldog clamp to interrupt the communication of RHV-IVC. (Fig. 4 ) (4) Following the double occlusion, parenchymal transection will be performed along the ischemic line on the liver surface and along the RHV landmark as reached deeper portion by using ultrasonic scalpel and BiClamp devices. In this process, intraparenchymal vascular and biliary structures greater than 5 mm will be ligated by using Hem-o-lock clips (Weck Surgical Instruments) and titanium clips. The parenchyma will be divided until the RHV is fully exposed on the transection surface, and then the resection will be completed. (Fig. 4 ) The caudo-dorsal approach combined with the Pringle maneuver only The main process is mostly consistent with the experimental group with one notable exception: the occlusion of RHV will not be adopted in this group. Post-operative management in the hospital Antibiotics will be administered prophylactically for 48 hours throughout the 48-hour perioperative period. Electrocardiograph monitoring and nasal catheter oxygen inhalation will last 24 hours. Blood routine, liver and renal function tests, and coagulation profile evaluation will be measured on postoperative days 1, 3, 5, and 7. The homogeneous postoperative management will be applied in both groups. Follow-up All patients will be assessed every three months following operation. These follow-up evaluations will include liver and renal function, blood routine examination, coagulation function test, AFP, PIVKA II, US/CT/MRI of the upper abdomen, recurrence information, and death information. Criteria for discontinuing or modifying allocated interventions Intraoperative ultrasonography indicates the presence of lesion in other liver segments requiring surgical intervention, the patient will be automatically excluded from the study. If a patient who has signed an informed consent form does not receive the assigned surgical method, they will be excluded from the study. Outcomes and measurements Primary outcome The primary outcome is the intra-operative blood loss volume, which will be calculated by using the formula: Blood loss volume = Total aspiration volume + Weights of soaked gauze - (Volume of flushing fluid + Weights of dry gauze). Secondary outcomes The secondary outcomes include perioperative outcomes. The short-term objective of this study is to explore the feasibility, safety, and efficacy of the double occlusion (RHV occlusion plus Pringle maneuver) in LARPH. The main measurements are as follows. Intraoperative: operative time, pringle maneuver time, blood transfusion volumes, intraoperative major events, conversion (defined as the change of surgical approach from laparoscopic to open) rate, the rate of RHV success exposure (definition: the successful exposure was defined as the complete exposure of RHV), the incidence of CO2 embolism. Postoperative: postoperative complications according to Clavien–Dindo classification, CCI score, post-operative stays in hospital, ICU stay, in-hospital, 30-day, and 90-day morbidity and mortality. The principal investigator is responsible for the observation, documentation, and management of adverse events that occur during the implementation process. In case of serious adverse events, timely reporting to the ethics committee is essential. Sample size As the primary outcome of this study, the intraoperative blood loss volume was used to calculate the sample size. According to a previously reported series, the intraoperative blood loss was 250 ml using the Glissonean pedicle‑first and venous craniocaudal approach [ 8 ]. In our initial practice, 157 ml intraoperative was observed. With a sampling ratio of 1 and an 80% power at the 0.050 level of significance, a sample size of 33 patients will be needed, and considering a dropout rate of 10%, 36 patients will be needed to be enrolled in each group. Data management The clinical data of participant is recorded at the Hospital Information System. Researchers will collect and load these data into case collection tables in a timely, complete, correct, and clear manner. The data is then saved to the database system and backed up in a timely manner.​ The contact information of patient and family would be saved by researcher to promote participant retention and complete follow-up. Statistical plan PSM analysis will be used to minimize the possible selection deviation, which will be carried out as 1:1 ratio matching and encompass the following variables: age, gender, BMI, ASA score, comorbidities, preoperative liver function, tumor numbers, and size. Perioperative outcomes will be assessed by Pearson’s chi-squared test, Fisher’s exact test, or McNemar’s test (for categorical variables), and the T-test or Mann–Whitney U test or Wilcoxon rank test (for continuous variables). Continuous data will be presented as mean and interquartile range and categorical variables will be expressed as numbers and percentages. Statistical analyses will be conducted using SPSS software version 27.0 (IBM SPSS Inc., Chicago, IL). A p-value of < 0.05 indicates statistical significance. Ethics, recruitment and dissemination This study will be conducted according to the Declaration of Helsinki. Team members (including all the authors) will explain the purpose, risks, benefits, and rights of participation in the trial to the eligible patient. Only after confirming that the patient understands the above information and voluntarily agrees to participate in the clinical study, the informed consent form could be signed. The study was approved by the Ethics Committee of West China Hospital (NO.2023616). The trial has been registered at the Chinese Clinical Trial Registry (chictr.org.cn), identifier: ChiCTR2300071832. The findings will be published in peer-reviewed journals and presented at scientific conferences. Discussion Anatomical resection (AR) is defined as the complete removal of the target portal territory, including the tumor and liver segment. Extensive researches have confirmed the efficacy of AR in reduced the risk of tumor recurrence and improved overall survival rates. [ 23 – 25 ]. Performing AR is technical demanding in both laparoscopic and open liver surgeries, which means a comprehensive preoperative plan and a standardized surgical procedure are essential to ensure perioperative safety. However, the current absence of standardized surgical procedures presents a significant challenge in implementing LARPH. In recent years, various strategies have emerged to optimize the process of LARPH. These techniques include the trans-fissural Glissonean approach, the intrahepatic Glissonian approach, the extrahepatic Glissonean approach, and dorsal approach [ 8 , 26 – 28 ]. These advancements have significantly contributed to the standardization of the surgical procedure for LARPH by enhancing the precise identification of target Glissonean pedicle and optimizing the technological process of liver resection. However, controlling intraoperative bleeding from RHV is still a formidable challenge for ensuring the safety of LARPH. In previous studies, excessive intraoperative blood loss and perioperative blood transfusions were associated with increased perioperative mortality and morbidity, unfavorable prognosis, as well as an increased recurrence rates of HCC [ 29 – 32 ]. The RHV was featured with thin vascular wall and numerous branches, which is susceptible to injury during parenchymal transection and traction [ 33 ]. When the Pringle maneuver is applied to occlude inflow blood, hemorrhage primarily originates hepatic venous system due to its lack of valves preventing blood reflux from IVC. Meanwhile, the venous wall is hard to repair in a moist surgical field. Additionally, the incidence of CO 2 gas embolism resulting from CO 2 infiltrates into the bloodstream is another main concern in LARPH. The presence of larger venous perforations on the RHV carries a potential risk of CO2 gas embolism, which poses adverse effects on respiration and circulation [ 14 ]. Given these risks, improving the safety of RHV exposure is crucial for optimizing LARPH. Theoretically, the technique of double occlusions (inflow and outflow) can significantly reduce blood loss to keep the operative field dry. After applying the double occlusion, the venous hole could be repaired with a lower risk of hemorrhage and CO 2 gas embolism. Traditionally, total vascular occlusion (involved clamping of the hepatic artery, portal vein, and IVC) has been applied for the above purposes [ 34 , 35 ]. However, the ischemia region was significantly extended in the total vascular occlusion technique, which would increase the risk of ischemia-reperfusion injury and liver function impaired. In addition, the occlusion of IVC would disturb the circulatory stabilization. After recanalizing the IVC, the ischemia-reperfusion would impair the renal function and even lead to acute renal insufficiency. In the present study, the outflow occlusion of the target area was innovative adopted: the RHV is selectively occluded in LARPH to control the outflow of S67. Combined with the pringle maneuver, our technique aims to retain the benefits of reduced the risk of hemorrhage and CO 2 gas embolism while avoiding the liver function impaired caused by total liver ischemia and the ischemia-reperfusion injury caused by clamping IVC. Meanwhile, this is the first study to compare the perioperative outcomes between double occlusions with the Pringle maneuver only. To date, this technique has not been supported by high-level medical evidence, only a few case reports and technique presentations for other segments resection described [ 36 – 38 ]. Herein, the safety and efficacy of the double occlusion (hepatic inflow control and target outflow control) will be assessed in this study. And the caudate lobe-first approach and a parenchymal transection direction from dorsal to ventral (caudo-dorsal approach) will be adopted in this study due to the following advantages: (1) reducing the risk of adverse injury caused by the various variations of the target branch (2) aligning with the laparoscopic caudodorsal view and (3) conforming to the anatomical features of the RHV (the main trunk of RHV was located on the dorsal side of the liver while its branches were extended toward the ventral side) [ 7 , 8 , 17 , 18 ]. In summary, LARPH is a technique-demanding procedure lacking standard surgical method by the hitherto. How to improve the safety of RHV exposure is a critical concern of LARPH. Pringle maneuver and RHV occlusion are innovatively combined to achieve parenchymal transection under the control of both hepatic inflow and outflow. This study adopts the innovative technique of double occlusion to perform LARPH. By developing and disseminating standardized protocols based on best practices and evidence from successful cases, this study aims to establish a safe, efficacy, and easily disseminated novel surgical technique. Abbreviations LARPH Laparoscopic anatomical right posterior hepatectomy CO 2 Carbon dioxide RHV Right hepatic vein CVP Central venous pressure CLCVP Controlling low central venous pressure IVC Inferior vena cava HCC Hepatocellular carcinoma ICC Intrahepatic cholangiocarcinoma AFP Alpha-fetoprotein PIVKA II Protein Induced by Vitamin K Absence or Antagonist II CEUS Contrast-enhanced ultrasonography CT Computed tomography MRI Magnetic Resonance Imaging CCI Comprehensive Complication Index AR Anatomical resection Declarations Ethics approval and consent to participate This study will be conducted according to the Declaration of Helsinki. The study was approved by the Ethics Committee of West China Hospital (NO.2023616). Eligible patients will be enrolled only after obtaining written informed consent. Consent for publication Not applicable. Availability of data and materials The data set will be kept confidential until the publication of trial results in an international journal. After that, the data set will be open upon an individual party’s request. Competing interests The authors declare that they have no competing interests. Funding: This work was supported by grant from the Sichuan Science and Technology Program (No. 2023YFQ0094). Funders have no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Authors' contributions Design and study conception: L.F., W.YG., L.B 1 . P.YF., and Y.WG.; Patients recruit: Y.WG., Y.YB., and L.B 2 ., Surgeon: L.F., W.YG., and L.B 1 . Acquisition and storage of data: Y.WG., Y.YB., and L.B 2 ., Analysis and interpretation: Y.WG., P.YF., L.F., Y.YB., and L.B 2 . Participation in drafting: Y.WG., P.YF., and L.F.; Participation in revising: all the authors. All the authors approved the final version. L.B 1 : Bo Li L.B 2 : Bin Liang Acknowledgements Not applicable. References Jia, C., et al., Laparoscopic liver resection: a review of current indications and surgical techniques. Hepatobiliary Surg Nutr, 2018. 7 (4): p. 277-288. Schmelzle, M., et al., Laparoscopic liver resection: indications, limitations, and economic aspects. Langenbecks Arch Surg, 2020. 405 (6): p. 725-735. Hasegawa, Y., et al., A novel model for prediction of pure laparoscopic liver resection surgical difficulty. Surg Endosc, 2017. 31 (12): p. 5356-5363. Sharma, K.C., et al., Laparoscopic surgery and its potential for medical complications. Heart Lung, 1997. 26 (1): p. 52-64; quiz 65-7. Fors, D., et al., Elevated PEEP without effect upon gas embolism frequency or severity in experimental laparoscopic liver resection. Br J Anaesth, 2012. 109 (2): p. 272-8. 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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-4727602","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Study protocol","associatedPublications":[],"authors":[{"id":332051589,"identity":"778eb675-791a-4027-b506-d6bcbfbef8af","order_by":0,"name":"Wugui Yang","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Wugui","middleName":"","lastName":"Yang","suffix":""},{"id":332051594,"identity":"0dd7e07b-8898-4999-9d68-6744ff1b7d24","order_by":1,"name":"Yufu Peng","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Yufu","middleName":"","lastName":"Peng","suffix":""},{"id":332051597,"identity":"3a3993e3-5cf9-4bf3-8976-3f9f5541e59a","order_by":2,"name":"Yubo Yang","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Yubo","middleName":"","lastName":"Yang","suffix":""},{"id":332051598,"identity":"8fa11fd4-f4bf-4548-a9e7-8b667b2dfefc","order_by":3,"name":"Bin Liang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Bin","middleName":"","lastName":"Liang","suffix":""},{"id":332051599,"identity":"7e5acaf4-6cbe-4b7b-ba9f-ed3878594476","order_by":4,"name":"Bo Li","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Bo","middleName":"","lastName":"Li","suffix":""},{"id":332051600,"identity":"b3dcb883-5769-447d-9414-8757a2a15518","order_by":5,"name":"Yonggang Wei","email":"","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":false,"prefix":"","firstName":"Yonggang","middleName":"","lastName":"Wei","suffix":""},{"id":332051601,"identity":"d764349c-fc02-44f4-918a-3b0640fe00f7","order_by":6,"name":"Fei Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAz0lEQVRIiWNgGAWjYBACPmYGhg8MBjZ2bOzNBw58+EGEFjZmBsYZDAZpyfw8xxIPzuwhRgsDSAvDYcaZM3yMD3OwEaOFncew4UNBGrPBDZ4Phxl4GOT5xQ4QchiPYeMMAxs+g9u9Gw4XWDAYzpydQFCL+WMeA6Atd85uODyDhyHB4DZhLYbNfwwOM264kfPgMA8bsVoYDEDez2EgVgtbYWMPJJANgIEsQdgv/PyHNzb8+AOOyscfPvywkeeXJqAFHUiQpnwUjIJRMApGAXYAAJIsQt7w27wQAAAAAElFTkSuQmCC","orcid":"","institution":"West China Hospital of Sichuan University","correspondingAuthor":true,"prefix":"","firstName":"Fei","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2024-07-12 03:18:50","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4727602/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4727602/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":62218865,"identity":"a8a34a1e-6597-435f-9e50-37488fb417e3","added_by":"auto","created_at":"2024-08-11 12:06:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":122283,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/8afb207be51f1b1cfbcc1677.png"},{"id":62220533,"identity":"f83b677e-2fb4-4ada-b639-f689d6853145","added_by":"auto","created_at":"2024-08-11 12:22:54","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6400289,"visible":true,"origin":"","legend":"\u003cp\u003eKey steps of the RHV exposure. \u003cstrong\u003eA\u003c/strong\u003e Mobilization of the right liver, \u003cstrong\u003eB \u003c/strong\u003eThe Makuuchi ligament was divided to detach the liver from IVC, \u003cstrong\u003eC \u003c/strong\u003eThe RHV was isolated from the caudal side, \u003cstrong\u003eD\u003c/strong\u003e The RHV was isolated from the cranial side \u003cstrong\u003eE\u003c/strong\u003e The RHV was isolated using the endo-retractor \u003cstrong\u003eF\u003c/strong\u003eExtrahepatic suspension of the RHV.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/7c01e93443c7666c2721ed01.png"},{"id":62218867,"identity":"ee096423-0445-4d23-831e-9e971bb910bd","added_by":"auto","created_at":"2024-08-11 12:06:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":6110025,"visible":true,"origin":"","legend":"\u003cp\u003eKey steps of the target Glissonean branch identification. \u003cstrong\u003eA\u003c/strong\u003e The caudate lobe was transected along the midline in parallel with the ventral central line of the IVC, \u003cstrong\u003eB\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe caudate process was detached from the posterior Glissonean pedicle and the G7 was identified, \u003cstrong\u003eC \u003c/strong\u003eThe caudate lobe was divided along the rightmost line of the IVC to expose the G67, \u003cstrong\u003eD\u003c/strong\u003e the G67 was exposed and suspended \u003cstrong\u003eE\u003c/strong\u003e The ischemic line functioned as the boundary of S7, \u003cstrong\u003eF \u003c/strong\u003eThe\u003cstrong\u003e \u003c/strong\u003eischemic line functioned as the boundary of S67\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/196014c436e7fcc030645e90.png"},{"id":62218868,"identity":"08190931-66cd-4269-83ae-14518c092338","added_by":"auto","created_at":"2024-08-11 12:06:54","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":6859934,"visible":true,"origin":"","legend":"\u003cp\u003eParenchymal transection under double occlusion. \u003cstrong\u003eA \u003c/strong\u003eThe pringle maneuver was adopted to control the hepatic inflow, \u003cstrong\u003eB\u003c/strong\u003e The RHV was clamped to control the hepatic outflow of S67, \u003cstrong\u003eC\u003c/strong\u003e Parenchymal was transected along the ischemic line on the liver surface, \u003cstrong\u003eD \u003c/strong\u003eParenchymal transection continued along the RHV landmark when RHV was exposed on the cross-section, \u003cstrong\u003eE \u003c/strong\u003eThe\u003cstrong\u003e \u003c/strong\u003efinal cutting surface of S67, \u003cstrong\u003eF\u003c/strong\u003e The final cutting surface of S7.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/8a83b8e249117a9d0af15cdc.png"},{"id":62222660,"identity":"f3cbcc28-9bcd-43ad-a07e-b1e0296e8129","added_by":"auto","created_at":"2024-08-11 12:39:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":18998105,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/cdef8582-6993-4e98-b79c-30143cdd016b.pdf"},{"id":62219529,"identity":"74c30c7d-b565-4d31-a4cb-02a495723754","added_by":"auto","created_at":"2024-08-11 12:14:54","extension":"doc","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":126858,"visible":true,"origin":"","legend":"","description":"","filename":"SPIRITFillablechecklist15Aug2013.doc","url":"https://assets-eu.researchsquare.com/files/rs-4727602/v1/e3061a94bcc288463aa6fd9b.doc"}],"financialInterests":"No competing interests reported.","formattedTitle":"Combination of the right hepatic vein occlusion and pringle maneuver in laparoscopic right posterior sectionectomy: protocol for a prospective non-randomized controlled study using propensity score-matched analysis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eContinuous advancements in laparoscopic equipment and the establishment of a robust theoretical framework in minimal invasive surgery are contribute to the increasing application of laparoscopic techniques in the treatment of hepatic space-occupying lesions. The indications of laparoscopic liver resection covered a wide range of benign diseases, malignant tumors, and living donor liver transplantation [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Despite these improvements, laparoscopic right posterior hepatectomy is still a technically challenging procedure, particularly concerning anatomical resection [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The challenges faced by surgeons in laparoscopic anatomical right posterior hepatectomy (LARPH) could be attributed to the following two significant factors. Firstly, the deep location of the posterior area within the subcostal cavity limited the surgical visibility and operative space during surgery, causing increased difficulty and complexity in exposure, parenchymal transection, and hemostasis. Secondly, the right hepatic vein (RHV) was featured with thin vascular wall and numerous branches, which was vulnerable to injury during the exposing procedure. Meanwhile, because of the absence of the venous valve in RHV to prevent blood reflux from the inferior vena cava, the presence of venous perforations on the RHV carried an evaluated risk of hemorrhage, which has the potential to obscure the operative field or disorder the circulatory dynamics. Additionally, the carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) gas embolism may occur when CO\u003csub\u003e2\u003c/sub\u003e infiltrates into the bloodstream through venous perforations, leading to detrimental effects on respiration and circulation [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. All these factors would contribute to an increased risk of conversion to open surgery and even lead to some potential life-threatening complications [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo enhance the practice of LARPH, several effective strategies have been reported in recent years. The caudate lobe‑first approach, proposed by Professor Honda, effectively simplified the exposure of the right posterior Glissonean pedicle by dividing of the caudate lobe [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. This method facilitated a clearer surgical field and improved the precision of the procedure. Additionally, conducting parenchymal transection from the dorsal to ventral sides was aligned with the unique laparoscopic caudodorsal view and the anatomical features of the hepatic vein [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], which potentially mitigated the risk of RHV injury. Furthermore, the Pringle maneuver could effectively control the hepatic inflow by occluding hepatoduodenal ligament, which has been demonstrated the effect in reducing the blood loss during parenchymal transection [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eUnfortunately, although these techniques have collectively contributed to the safe, efficient LARPH, they have yet to address the safe exposure of the right hepatic vein. In terms of anesthesia intervention, several studies demonstrated that a low central venous pressure (CVP) could reduce the risk of bleeding and emphasized the necessity of controlling low central venous pressure (CLCVP) for hepatic vein exposure [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. However, managing CLCVP was technique demanding and involved potential risks of CO\u003csub\u003e2\u003c/sub\u003e gas embolism, acidosis, and acute kidney injury [\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. It is challenging to balance the risk of hemorrhage from the hepatic vein and the risk of CO\u003csub\u003e2\u003c/sub\u003e gas embolism from managing CLCVP, particularly in less experienced surgical centers. With regard to surgical technique, the adoption of a root-to-peripheral approach to expose RHV was hopeful in mitigating the risk of bifurcation injury [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. However, this technique required a high degree of surgical expertise. Meanwhile, the injury of hepatic vein caused by anatomical variation, tissue traction, and unintentional incision was hard to avoid using this approach. Given these complexities, there is a pressing need for practical and widely accepted strategies to ensure the safe exposure of RHV.\u003c/p\u003e \u003cp\u003eHerein, we propose an innovative technique of RHV occlusion aimed at ensuring safe exposure of RHV by interrupting the communication of RHV-IVC. This technique is designed to control the blood loss by preventing the blood reflux from IVC after hepatic inflow occlusion and to mitigate the risk of CO\u003csub\u003e2\u003c/sub\u003e gas embolism by preventing CO\u003csub\u003e2\u003c/sub\u003e into the bloodstream of IVC. Meanwhile, the Pringle maneuver will be adopted in this study to minimize intraoperative blood loss by controlling the hepatic inflow. Furthermore, the caudo-dorsal approach will be adopted to identify the target Glissonean pedicle and transecting the parenchyma in this study.\u003c/p\u003e \u003cp\u003eThis study will detail steps this novel technique for laparoscopic anatomical right posterior sectionectomy using the caudo-dorsal approach combined with double occlusion (RHV occlusion plus Pringle maneuver). The feasibility, safety, and efficacy of the double occlusion will be evaluated in this prospective study.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy setting\u003c/h2\u003e \u003cp\u003eThe study is a prospective non-randomized controlled trial aimed at evaluating the feasibility, safety, and efficacy of the double occlusion (RHV occlusion plus Pringle maneuver) in LARPH. This study will be conducted in two liver surgery centers: Division of Liver Surgery, Department of General Surgery, West China Hospital of Sichuan University, China; Department of General Surgery, Sanya People\u0026rsquo;s Hospital, China.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eEligibility criteria\u003c/h2\u003e \u003cp\u003eThis study will consecutively enroll eligible patients undergoing LARPH from May 2023 to December 2025. Patients undergoing LARPH using the novel technique (double occlusion) will be assigned to the experimental group, while those undergoing LARPH by using the traditional technique (Pringle maneuver only) will be assigned to the control group. Surgical strategies for all patients will be formulated and acquired consensus by three experienced surgeons. And patient will be matched in both groups on a 1:1 basis propensity score matching (PSM) to mitigate the potential selection bias (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eInclusion criteria\u003c/h2\u003e \u003cp\u003e(1) Patients aged 18 to 80 years old, inclusive of both males and females;\u003c/p\u003e \u003cp\u003e(2) Patients eligible for general anesthesia or laparoscopic hepatectomy without contraindications;\u003c/p\u003e \u003cp\u003e(3) Liver function classified as Child-Pugh A, with Indocyanine green (ICG) clearance test showing a retention ratio after 15 minutes\u0026thinsp;\u0026lt;\u0026thinsp;15% [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e];\u003c/p\u003e \u003cp\u003e(4) Diagnosis of liver malignant tumor, which included hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), combined HCC-ICC, or liver metastasis.\u003c/p\u003e \u003cp\u003e(5) Tumor diameter\u0026thinsp;\u0026le;\u0026thinsp;5 cm, without invasion over liver capsule or diaphragm;\u003c/p\u003e \u003cp\u003e(6) Suitability for LARPH (S7 and S67) confirmed by a feasibility evaluation conducted by three experienced hepatobiliary pancreatic (HBP) experts, with an expected incision margin\u0026thinsp;\u0026ge;\u0026thinsp;1cm.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003eExclusion criteria\u003c/h2\u003e \u003cp\u003e(1) Patients with previous upper-abdominal surgery history;\u003c/p\u003e \u003cp\u003e(2) Presence of cancer embolus in the main trunk of portal vein, bile duct, or RHV;\u003c/p\u003e \u003cp\u003e(3) LARPH performed with other organs resection (except for gallbladder);\u003c/p\u003e \u003cp\u003e(4) LARPH performed with additional segments resection or performed with radiofrequency ablation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003eIntervention\u003c/h2\u003e \u003cdiv id=\"Sec8\" class=\"Section4\"\u003e \u003ch2\u003ePre-operative assessment\u003c/h2\u003e \u003cp\u003eA comprehensive preoperative assessment will be conducted for all patients. The blood tests include complete blood count, liver and renal function tests, coagulation profile evaluation, serum alpha-fetoprotein (AFP) level, Protein Induced by Vitamin K Absence or Antagonist II (PIVKA II) level, and hepatitis B and C serology screening. Liver function will be assessed using the Child-Pugh grading system and the ICG-15 clearance test. Tumor characteristics including size, number, and location will be assessed through following imaging examinations: abdominal enhanced computed tomography (CT), contrast-enhanced ultrasonography (CEUS), or Magnetic Resonance Imaging (MRI). Patient's performance status will be recorded according to Eastern Cooperative Oncology Group (ECOG) criteria [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] and the American Society of Anesthesiologists physical status [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Additionally, chest CT scan will be utilized to evaluate pulmonary comorbidities.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003eSurgical technique\u003c/h2\u003e \u003cp\u003eGeneral steps\u003c/p\u003e \u003cp\u003eThe patient will be placed in the left 30 \u0026ordm; trunk rotation Trendelenburg position. Five trocars will be inserted into the upper abdomen as follows: one optical trocar (10 mm), two main operating trocars (12 mm) and two assistant trocars (5 mm). And the pneumoperitoneum will be established with CO\u003csub\u003e2\u003c/sub\u003e and the intraperitoneal pressure will maintain 12\u0026ndash;14 mmHg. A 30\u0026deg; laparoscope will provide a flexible view during this procedure.\u003c/p\u003e \u003cp\u003eThe caudo-dorsal approach combined with the occlusion of the RHV and Pringle maneuver\u003c/p\u003e \u003cp\u003e(1) The right liver will be fully mobilized by dissecting perihepatic ligaments, allowing it to be uplifted and rotated towards the left side. Makuuchi ligament will be divided then to gain access to the secondary porta of the liver. The RHV will be isolated by dissecting the secondary porta from both the caudal and cranial sides. Extrahepatic suspension of RHV will be performed using an endo-retractor with a string (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e(2) The caudate lobe first approach will be adopted to access and identify the target Glissonean pedicle (G7 or G67). For the exposure of G7, the caudate lobe will be transected along the midline in parallel with the ventral central line of the IVC. This is followed by detaching the caudate process from the posterior Glissonean pedicle. Then the G7 will be identified [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Theoretically, the G67 crosses over the border between the right posterior section and the caudate lobe. Therefore, the G67 could be isolated by dividing the caudate lobe. After identifying the ventral aspect of G67, the dorsal aspect of G67 will be exposed by dividing the caudate lobe along the rightmost line of the IVC between the right Glissonean pedicle and IVC [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The target pedicle is divided and the ischemic demarcation of its portal territory will be outlined on the liver surface (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e(3) The pringle maneuver will be prepared and applied intermittently during parenchymal transection (15 min hepatic inflow occlusion with 5 min release for one cycle). The root of RHV will be clamped extrahepatic by a Bulldog clamp to interrupt the communication of RHV-IVC. (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e(4) Following the double occlusion, parenchymal transection will be performed along the ischemic line on the liver surface and along the RHV landmark as reached deeper portion by using ultrasonic scalpel and BiClamp devices. In this process, intraparenchymal vascular and biliary structures greater than 5 mm will be ligated by using Hem-o-lock clips (Weck Surgical Instruments) and titanium clips. The parenchyma will be divided until the RHV is fully exposed on the transection surface, and then the resection will be completed. (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe caudo-dorsal approach combined with the Pringle maneuver only\u003c/p\u003e \u003cp\u003eThe main process is mostly consistent with the experimental group with one notable exception: the occlusion of RHV will not be adopted in this group.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003ePost-operative management in the hospital\u003c/h2\u003e \u003cp\u003eAntibiotics will be administered prophylactically for 48 hours throughout the 48-hour perioperative period. Electrocardiograph monitoring and nasal catheter oxygen inhalation will last 24 hours. Blood routine, liver and renal function tests, and coagulation profile evaluation will be measured on postoperative days 1, 3, 5, and 7. The homogeneous postoperative management will be applied in both groups.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eFollow-up\u003c/h2\u003e \u003cp\u003eAll patients will be assessed every three months following operation. These follow-up evaluations will include liver and renal function, blood routine examination, coagulation function test, AFP, PIVKA II, US/CT/MRI of the upper abdomen, recurrence information, and death information.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eCriteria for discontinuing or modifying allocated interventions\u003c/h2\u003e \u003cp\u003eIntraoperative ultrasonography indicates the presence of lesion in other liver segments requiring surgical intervention, the patient will be automatically excluded from the study. If a patient who has signed an informed consent form does not receive the assigned surgical method, they will be excluded from the study.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eOutcomes and measurements\u003c/h2\u003e \u003cdiv id=\"Sec14\" class=\"Section3\"\u003e \u003ch2\u003ePrimary outcome\u003c/h2\u003e \u003cp\u003eThe primary outcome is the intra-operative blood loss volume, which will be calculated by using the formula: Blood loss volume\u0026thinsp;=\u0026thinsp;Total aspiration volume\u0026thinsp;+\u0026thinsp;Weights of soaked gauze - (Volume of flushing fluid\u0026thinsp;+\u0026thinsp;Weights of dry gauze).\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eSecondary outcomes\u003c/h2\u003e \u003cp\u003eThe secondary outcomes include perioperative outcomes.\u003c/p\u003e \u003cp\u003eThe short-term objective of this study is to explore the feasibility, safety, and efficacy of the double occlusion (RHV occlusion plus Pringle maneuver) in LARPH. The main measurements are as follows.\u003c/p\u003e \u003cp\u003eIntraoperative: operative time, pringle maneuver time, blood transfusion volumes, intraoperative major events, conversion (defined as the change of surgical approach from laparoscopic to open) rate, the rate of RHV success exposure (definition: the successful exposure was defined as the complete exposure of RHV), the incidence of CO2 embolism.\u003c/p\u003e \u003cp\u003ePostoperative: postoperative complications according to Clavien\u0026ndash;Dindo classification, CCI score, post-operative stays in hospital, ICU stay, in-hospital, 30-day, and 90-day morbidity and mortality.\u003c/p\u003e \u003cp\u003eThe principal investigator is responsible for the observation, documentation, and management of adverse events that occur during the implementation process. In case of serious adverse events, timely reporting to the ethics committee is essential.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eSample size\u003c/h2\u003e \u003cp\u003eAs the primary outcome of this study, the intraoperative blood loss volume was used to calculate the sample size. According to a previously reported series, the intraoperative blood loss was 250 ml using the Glissonean pedicle‑first and venous craniocaudal approach [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In our initial practice, 157 ml intraoperative was observed. With a sampling ratio of 1 and an 80% power at the 0.050 level of significance, a sample size of 33 patients will be needed, and considering a dropout rate of 10%, 36 patients will be needed to be enrolled in each group.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eData management\u003c/h2\u003e \u003cp\u003eThe clinical data of participant is recorded at the Hospital Information System. Researchers will collect and load these data into case collection tables in a timely, complete, correct, and clear manner. The data is then saved to the database system and backed up in a timely manner.​ The contact information of patient and family would be saved by researcher to promote participant retention and complete follow-up.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eStatistical plan\u003c/h2\u003e \u003cp\u003ePSM analysis will be used to minimize the possible selection deviation, which will be carried out as 1:1 ratio matching and encompass the following variables: age, gender, BMI, ASA score, comorbidities, preoperative liver function, tumor numbers, and size. Perioperative outcomes will be assessed by Pearson\u0026rsquo;s chi-squared test, Fisher\u0026rsquo;s exact test, or McNemar\u0026rsquo;s test (for categorical variables), and the T-test or Mann\u0026ndash;Whitney U test or Wilcoxon rank test (for continuous variables). Continuous data will be presented as mean and interquartile range and categorical variables will be expressed as numbers and percentages. Statistical analyses will be conducted using SPSS software version 27.0 (IBM SPSS Inc., Chicago, IL). A p-value of \u0026lt;\u0026thinsp;0.05 indicates statistical significance.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eEthics, recruitment and dissemination\u003c/h2\u003e \u003cp\u003e This study will be conducted according to the Declaration of Helsinki. Team members (including all the authors) will explain the purpose, risks, benefits, and rights of participation in the trial to the eligible patient. Only after confirming that the patient understands the above information and voluntarily agrees to participate in the clinical study, the informed consent form could be signed. The study was approved by the Ethics Committee of West China Hospital (NO.2023616). The trial has been registered at the Chinese Clinical Trial Registry (chictr.org.cn), identifier: ChiCTR2300071832. The findings will be published in peer-reviewed journals and presented at scientific conferences.\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eAnatomical resection (AR) is defined as the complete removal of the target portal territory, including the tumor and liver segment. Extensive researches have confirmed the efficacy of AR in reduced the risk of tumor recurrence and improved overall survival rates. [\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Performing AR is technical demanding in both laparoscopic and open liver surgeries, which means a comprehensive preoperative plan and a standardized surgical procedure are essential to ensure perioperative safety. However, the current absence of standardized surgical procedures presents a significant challenge in implementing LARPH.\u003c/p\u003e \u003cp\u003eIn recent years, various strategies have emerged to optimize the process of LARPH. These techniques include the trans-fissural Glissonean approach, the intrahepatic Glissonian approach, the extrahepatic Glissonean approach, and dorsal approach [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan additionalcitationids=\"CR27\" citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. These advancements have significantly contributed to the standardization of the surgical procedure for LARPH by enhancing the precise identification of target Glissonean pedicle and optimizing the technological process of liver resection.\u003c/p\u003e \u003cp\u003eHowever, controlling intraoperative bleeding from RHV is still a formidable challenge for ensuring the safety of LARPH. In previous studies, excessive intraoperative blood loss and perioperative blood transfusions were associated with increased perioperative mortality and morbidity, unfavorable prognosis, as well as an increased recurrence rates of HCC [\u003cspan additionalcitationids=\"CR30 CR31\" citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The RHV was featured with thin vascular wall and numerous branches, which is susceptible to injury during parenchymal transection and traction [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. When the Pringle maneuver is applied to occlude inflow blood, hemorrhage primarily originates hepatic venous system due to its lack of valves preventing blood reflux from IVC. Meanwhile, the venous wall is hard to repair in a moist surgical field. Additionally, the incidence of CO\u003csub\u003e2\u003c/sub\u003e gas embolism resulting from CO\u003csub\u003e2\u003c/sub\u003e infiltrates into the bloodstream is another main concern in LARPH. The presence of larger venous perforations on the RHV carries a potential risk of CO2 gas embolism, which poses adverse effects on respiration and circulation [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Given these risks, improving the safety of RHV exposure is crucial for optimizing LARPH.\u003c/p\u003e \u003cp\u003eTheoretically, the technique of double occlusions (inflow and outflow) can significantly reduce blood loss to keep the operative field dry. After applying the double occlusion, the venous hole could be repaired with a lower risk of hemorrhage and CO\u003csub\u003e2\u003c/sub\u003e gas embolism. Traditionally, total vascular occlusion (involved clamping of the hepatic artery, portal vein, and IVC) has been applied for the above purposes [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. However, the ischemia region was significantly extended in the total vascular occlusion technique, which would increase the risk of ischemia-reperfusion injury and liver function impaired. In addition, the occlusion of IVC would disturb the circulatory stabilization. After recanalizing the IVC, the ischemia-reperfusion would impair the renal function and even lead to acute renal insufficiency.\u003c/p\u003e \u003cp\u003eIn the present study, the outflow occlusion of the target area was innovative adopted: the RHV is selectively occluded in LARPH to control the outflow of S67. Combined with the pringle maneuver, our technique aims to retain the benefits of reduced the risk of hemorrhage and CO\u003csub\u003e2\u003c/sub\u003e gas embolism while avoiding the liver function impaired caused by total liver ischemia and the ischemia-reperfusion injury caused by clamping IVC. Meanwhile, this is the first study to compare the perioperative outcomes between double occlusions with the Pringle maneuver only. To date, this technique has not been supported by high-level medical evidence, only a few case reports and technique presentations for other segments resection described [\u003cspan additionalcitationids=\"CR37\" citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Herein, the safety and efficacy of the double occlusion (hepatic inflow control and target outflow control) will be assessed in this study.\u003c/p\u003e \u003cp\u003eAnd the caudate lobe-first approach and a parenchymal transection direction from dorsal to ventral (caudo-dorsal approach) will be adopted in this study due to the following advantages: (1) reducing the risk of adverse injury caused by the various variations of the target branch (2) aligning with the laparoscopic caudodorsal view and (3) conforming to the anatomical features of the RHV (the main trunk of RHV was located on the dorsal side of the liver while its branches were extended toward the ventral side) [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn summary, LARPH is a technique-demanding procedure lacking standard surgical method by the hitherto. How to improve the safety of RHV exposure is a critical concern of LARPH. Pringle maneuver and RHV occlusion are innovatively combined to achieve parenchymal transection under the control of both hepatic inflow and outflow. This study adopts the innovative technique of double occlusion to perform LARPH. By developing and disseminating standardized protocols based on best practices and evidence from successful cases, this study aims to establish a safe, efficacy, and easily disseminated novel surgical technique.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"543\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLARPH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eLaparoscopic anatomical right posterior hepatectomy\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCarbon dioxide\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRHV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eRight hepatic vein\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCVP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eCentral venous pressure\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCLCVP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eControlling low central venous pressure\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIVC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eInferior vena cava\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eHCC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eHepatocellular carcinoma\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eICC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eIntrahepatic cholangiocarcinoma\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAFP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAlpha-fetoprotein\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePIVKA II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eProtein Induced by Vitamin K Absence or Antagonist II\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCEUS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eContrast-enhanced ultrasonography\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eComputed tomography\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMRI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMagnetic Resonance Imaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCCI\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eComprehensive Complication Index\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAnatomical resection\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study will be conducted according to the Declaration of Helsinki. The study was approved by the Ethics Committee of West China Hospital (NO.2023616). Eligible patients will be enrolled only after obtaining written informed consent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data set will be kept confidential until the publication of trial results in an international journal. After that, the data set will be open upon an individual party’s request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by grant from the Sichuan Science and Technology Program (No. 2023YFQ0094). Funders have no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDesign and study conception: L.F., W.YG., L.B\u003csup\u003e1\u003c/sup\u003e. P.YF., and Y.WG.;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePatients recruit: Y.WG., Y.YB., and L.B\u003csup\u003e2\u003c/sup\u003e.,\u003c/p\u003e\n\u003cp\u003eSurgeon: L.F., W.YG., and L.B\u003csup\u003e1\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAcquisition and storage of data: Y.WG., Y.YB., and L.B\u003csup\u003e2\u003c/sup\u003e.,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAnalysis and interpretation: Y.WG., P.YF., L.F., Y.YB., and L.B\u003csup\u003e2\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eParticipation in drafting: Y.WG., P.YF., and L.F.;\u003c/p\u003e\n\u003cp\u003eParticipation in revising: all the authors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll the authors approved the final version.\u003c/p\u003e\n\u003cp\u003eL.B\u003csup\u003e1\u003c/sup\u003e: Bo Li\u003c/p\u003e\n\u003cp\u003eL.B\u003csup\u003e2\u003c/sup\u003e: Bin Liang\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eJia, C., et al., \u003cem\u003eLaparoscopic liver resection: a review of current indications and surgical techniques.\u003c/em\u003e Hepatobiliary Surg Nutr, 2018. \u003cstrong\u003e7\u003c/strong\u003e(4): p. 277-288.\u003c/li\u003e\n\u003cli\u003eSchmelzle, M., et al., \u003cem\u003eLaparoscopic liver resection: indications, limitations, and economic aspects.\u003c/em\u003e Langenbecks Arch Surg, 2020. \u003cstrong\u003e405\u003c/strong\u003e(6): p. 725-735.\u003c/li\u003e\n\u003cli\u003eHasegawa, Y., et al., \u003cem\u003eA novel model for prediction of pure laparoscopic liver resection surgical difficulty.\u003c/em\u003e Surg Endosc, 2017. \u003cstrong\u003e31\u003c/strong\u003e(12): p. 5356-5363.\u003c/li\u003e\n\u003cli\u003eSharma, K.C., et al., \u003cem\u003eLaparoscopic surgery and its potential for medical complications.\u003c/em\u003e Heart Lung, 1997. \u003cstrong\u003e26\u003c/strong\u003e(1): p. 52-64; quiz 65-7.\u003c/li\u003e\n\u003cli\u003eFors, D., et al., \u003cem\u003eElevated PEEP without effect upon gas embolism frequency or severity in experimental laparoscopic liver resection.\u003c/em\u003e Br J Anaesth, 2012. \u003cstrong\u003e109\u003c/strong\u003e(2): p. 272-8.\u003c/li\u003e\n\u003cli\u003eEgger, M.E., et al., \u003cem\u003eAnesthetic and operative considerations for laparoscopic liver resection.\u003c/em\u003e Surgery, 2017. \u003cstrong\u003e161\u003c/strong\u003e(5): p. 1191-1202.\u003c/li\u003e\n\u003cli\u003eHomma, Y., et al., \u003cem\u003ePure laparoscopic right posterior sectionectomy using the caudate lobe-first approach.\u003c/em\u003e Surg Endosc, 2019. \u003cstrong\u003e33\u003c/strong\u003e(11): p. 3851-3857.\u003c/li\u003e\n\u003cli\u003eFerrero, A., et al., \u003cem\u003eLaparoscopic right posterior anatomic liver resections with Glissonean pedicle-first and venous craniocaudal approach.\u003c/em\u003e Surg Endosc, 2021. \u003cstrong\u003e35\u003c/strong\u003e(1): p. 449-455.\u003c/li\u003e\n\u003cli\u003eMaeda, K., et al., \u003cem\u003ePure laparoscopic right hemihepatectomy using the caudodorsal side approach (with videos).\u003c/em\u003e J Hepatobiliary Pancreat Sci, 2018. \u003cstrong\u003e25\u003c/strong\u003e(7): p. 335-341.\u003c/li\u003e\n\u003cli\u003ePringle, J.H., \u003cem\u003eV. 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systematic review and meta-analysis.\u003c/em\u003e Asian J Surg, 2021. \u003cstrong\u003e44\u003c/strong\u003e(9): p. 1143-1150.\u003c/li\u003e\n\u003cli\u003eGalperin, E.I., et al., \u003cem\u003eA new simplified method of selective exposure of hepatic pedicles for controlled hepatectomies.\u003c/em\u003e HPB Surg, 1989. \u003cstrong\u003e1\u003c/strong\u003e(2): p. 119-30.\u003c/li\u003e\n\u003cli\u003eMachado, M.A., et al., \u003cem\u003eIntrahepatic Glissonian approach for laparoscopic right segmental liver resections.\u003c/em\u003e Am J Surg, 2008. \u003cstrong\u003e196\u003c/strong\u003e(4): p. e38-42.\u003c/li\u003e\n\u003cli\u003eLee, M.J., et al., \u003cem\u003eTailored Strategy for Dissecting the Glissonean Pedicle in Laparoscopic Right Posterior Sectionectomy: Extrahepatic, Intrahepatic, and Transfissural Glissonean Approaches (with Video).\u003c/em\u003e World J Surg, 2022. \u003cstrong\u003e46\u003c/strong\u003e(8): p. 1962-1968.\u003c/li\u003e\n\u003cli\u003eYamamoto, 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\u003cem\u003eControl of the inflow and outflow system during liver resection.\u003c/em\u003e J Hepatobiliary Pancreat Sci, 2012. \u003cstrong\u003e19\u003c/strong\u003e(1): p. 15-8.\u003c/li\u003e\n\u003cli\u003eQu, Z., et al., \u003cem\u003eTreatment of hepatic venous system hemorrhage and carbon dioxide gas embolization during laparoscopic hepatectomy via hepatic vein approach.\u003c/em\u003e Front Oncol, 2022. \u003cstrong\u003e12\u003c/strong\u003e: p. 1060823.\u003c/li\u003e\n\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":"Laparoscopic liver resection, Anatomical resection, Occlusion of right hepatic vein, Pringle maneuver, Double occlusion","lastPublishedDoi":"10.21203/rs.3.rs-4727602/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4727602/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e \u003cp\u003eLaparoscopic right posterior hepatectomy, particularly for standard anatomical resection, presents significant technical challenges. Achieving complete exposure of right hepatic vein (RHV) is the critical step in this procedure. To date, there is currently no universally accepted technique to ensure the safe exposure of RHV. To address this gap, this study designs a novel technique involving RHV occlusion and Pringle maneuver for enhancing the safety of RHV exposure in laparoscopic anatomical right posterior hepatectomy (LARPH). A comparative analysis between this innovative approach and traditional technique is performing to investigate the safety and efficacy of this innovative approach.\u003c/p\u003e\u003ch2\u003eMethods and analysis:\u003c/h2\u003e \u003cp\u003eThis prospective non-randomized controlled trial is being conducted at West China Hospital and Sanya People\u0026rsquo;s Hospital. Patients undergoing LARPH using the novel technique (double occlusion) will be assigned to the experimental group, while those using the traditional technique (Pringle maneuver only) will be assigned to the control group. Perioperative outcomes and follow-up data will be collected and analyzed. PSM analysis with 1:1 ratio matching will be used to mitigate the potential selection deviation. The primary outcome is intraoperative blood loss. Secondary outcomes include the rate of successful RHV exposure, the incidence of CO\u003csub\u003e2\u003c/sub\u003e embolism, postoperative complications, as well as morbidity and mortality at 30 days and 90 days.\u003c/p\u003e\u003ch2\u003eDiscussion\u003c/h2\u003e \u003cp\u003eIn this study, the outflow occlusion of the target area is innovative adopted: the RHV is selectively occluded in LARPH to control the outflow of S67. Combined with the pringle maneuver, our technique potential has the benefits of reduced the risk of hemorrhage and CO\u003csub\u003e2\u003c/sub\u003e gas embolism. By developing and disseminating standardized protocols based on best practices and evidence from successful cases, this study aims to establish a safe, efficacy, and easily disseminated novel surgical technique.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e \u003cp\u003eThis study has been prospectively registered at Chinese Clinical Trial Registry (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.chictr.org.cn/index.html\u003c/span\u003e\u003cspan address=\"https://www.chictr.org.cn/index.html\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) on May 26, 2023. The identifier is ChiCTR2300071832 and the registry name is \u0026ldquo;Caudodorsal approach combined with the occlusion of the right hepatic vein and Pringle maneuver in laparoscopic right posterior sectionectomy\u0026rdquo;.\u003c/p\u003e","manuscriptTitle":"Combination of the right hepatic vein occlusion and pringle maneuver in laparoscopic right posterior sectionectomy: protocol for a prospective non-randomized controlled study using propensity score-matched analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-11 12:06:49","doi":"10.21203/rs.3.rs-4727602/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":"1f7cd7cb-1865-4b94-bf13-0db2a15df09c","owner":[],"postedDate":"August 11th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-08-11T12:06:51+00:00","versionOfRecord":[],"versionCreatedAt":"2024-08-11 12:06:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4727602","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4727602","identity":"rs-4727602","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}