What is the best technique in parenchymal transection in laparoscopic liver resection? Comprehensive review for the clinical question on the 2nd International Consensus Conference on Laparoscopic Liver Resection

Current Status of Laparoscopic Liver Resection

The evolution of laparoscopic liver surgery, originating in the 1990s, has been marked by significant advancements and milestones, overcoming initial technical hurdles and gaining widespread acceptance within the surgical community as a precise and safe alternative to open procedures. Along this journey, numerous challenges emerged, leading to the accumulation of evidence and the development of guidelines aimed at assisting surgeons in determining the safety, suitability, and complexity of laparoscopic liver resection. This chapter provides a thorough examination of key aspects of laparoscopic liver resection, including difficulty scoring systems, criteria for patient selection, technical considerations, outcomes across different types of liver lesions, and the innovative solutions developed to address challenges, thus offering a comprehensive overview of laparoscopic liver resection, and highlighting its evolving significance in modern hepatobiliary surgery.

Safety and Feasibility of Laparoscopic Liver Resection with the Clamp-Crush Method Using the BiSect

BACKGROUND

Various energy devices are available for resection of the liver parenchyma during laparoscopic liver resection (LLR). We have historically performed liver resections using the Cavitron Ultrasonic Surgical Aspirator (CUSA). More recently, we have used new bipolar forceps (BiSect; Erbe Elektromedizin GmbH, Tübingen, Germany) to perform clamp-crush dissection with good results. The BiSect is a reusable bipolar forceps with a laparoscopic dissecting forceps tip and both an incision mode and coagulation mode. We evaluated the perioperative clinical course of patients who underwent LLR using the clamp-crush method with the BiSect compared with the CUSA.

METHODS

This single-center case control study involved patients with liver metastasis from colorectal cancer who underwent LLR using either the BiSect or CUSA at our hospital from January 2019 to December 2022. We performed the LLR using CUSA from January 2019 to early October 2020. After introduction of the BiSect in late October 2020, we used BiSect for the LLR. Before surgery, the three-dimensional liver was constructed based on computed tomography images, and a preoperative simulation was performed. We evaluated the results of LLR using the BiSect versus the CUSA and assessed the short-term results of LLR.

RESULTS

During the study period, we performed partial liver resection using the BiSect in 26 patients and the CUSA in 16 patients. In the BiSect group, the median bleeding volume was 55 mL, the median operation time was 227 minutes, and the median postoperative length of hospital stay was 9 days. In the CUSA group, the median bleeding volume was 87 mL, the median operation time was 305 minutes, and the median postoperative length of hospital stay was 10 days. There were no statistically significant differences in the clinical course including bile leakage, bile duct stenosis, and post operative hospital stay between the two groups.

CONCLUSIONS

Compared with LLR using the CUSA, the clamp-crush method using the BiSect in LLR is a safe and useful liver transection technique. Further study should be conducted to clarify whether BiSect is safe and useful in LLR for patients with other tumor types and patients who undergo other procedures.

The CUSA Clarity Soft Tissue Removal Study: Clinical Performance Investigation of the CUSA Clarity Ultrasonic Surgical Aspirator System for Soft Tissue Removal During Liver Surgery

Background: Intraoperative blood loss has an unfavorable impact on the outcome of patients undergoing liver surgery. Today, the use of devices capable of minimizing this risk with high technical performance becomes mandatory. Into this scenario fits the CUSA® Clarity Ultrasonic Surgical Aspirator System. This prospective survey involving five liver surgery centers had the objective of investigating whether this innovative ultrasonic surgical aspirator is safe and effective in the transection of the liver parenchyma. Materials and Methods: This clinical study was a prospective, multicenter, single-arm Post-Market Clinical Follow-up study investigating 100 subjects who underwent liver surgery using the CUSA Clarity Ultrasonic Surgical Aspirator System at five centers during a period of 1 year and 8 months. After collecting all the patient's clinical information and instrument usage details, surgeons completed a brief survey giving their opinions on the performance of CUSA. Therefore, safety and efficacy outcomes were evaluated. Results: Surgeons had a 95% success rate in complete removal of the mass with an average overall operative time of 4 hours and 34 minutes. Overall, there were no complications or device deficiencies. Conclusion: The CUSA Clarity Ultrasonic Surgical Aspirator System performs well during liver surgery with a low complication rate. ClinicalTrials.gov Identifier: NCT04298268.

A "cui prodest" evaluation on the development of a minimally invasive liver surgery program: a differential benefit analysis of open and laparoscopic approach for left and right hemihepatectomies

BACKGROUND

The correlation between technical feasibility and short-term clinical advantage provided by laparoscopic over open technique for major hepatectomies is unclear. This monocentric retrospective study investigates the possible differences in the benefit provided by minimally invasive approach between left and right hepatectomy, deepening the concept of differential benefit in the setting of anatomical major resections.

METHODS

All hemihepatectomies performed from January 2004 to December 2021 were identified in the institutional database. A propensity score method was used to match minimal invasive (MILS) and open pairs in the left hemihepatectomies (LH) and right hemihepatectomies (RH) groups with a 1:1 ratio to adjust any potential selection bias. The differential benefit for left and right hepatectomy provided by laparoscopic over open technique was evaluated in a pure analysis (i.e., including cases converted to open) and a risk-adjusted analysis (i.e., after excluding open conversion from the laparoscopic series).

RESULTS

The analysis of the risk-adjusted differential benefit demonstrated better result of the MILS in the RH group than in the LH group, in terms of blood loss (∆ blood loss - 150 and - 350, respectively; differential benefit: 200 mL, p < 0.05), morbidity (∆ rate of morbidity - 11.3% and - 18.1%, respectively; differential benefit: 6.8%, p < 0.05) and length of stay, LOS (∆ LOS - 1 day and - 3 days, respectively; differential benefit: 2 days, p < 0.05).

CONCLUSION

While MILS is associated with improved clinical outcomes both in left and right hepatectomy procedures, the greater advantage provided by laparoscopy was documented in patients undergoing right hepatectomy, i.e. for more technically demanding procedures. A MILS program should include the broadest range of liver resections to ensure the full benefits of the laparoscopic technique.

The Outcome of Conversion to Hand-Assisted Laparoscopic Surgery in Laparoscopic Liver Resection

BACKGROUND

Hand-assisted laparoscopic surgery (HALS) is known as a useful option. However, the outcome and predictor of conversion to HALS in laparoscopic liver resection (LLR) are unclear.

METHODS

Data from consecutive patients who planned pure LLR between 2011 and 2020 were retrospectively reviewed. Univariate and multivariate analyses were performed and compared pure LLR, HALS, and converted open liver resection (OLR).

RESULTS

Among the 169 LLRs, conversion to HALS was performed in 19 (11.2%) and conversion to OLR in 16 (9.5%). The most frequent reasons for conversion to HALS were failure to progress (11 cases). Subsequently, bleeding (3 cases), severe adhesion (2 cases), and oncological factors (2 cases) were the reasons. In the multivariable analysis, the tumor located in segments 7 or 8 (p = 0.002) was evaluated as a predictor of conversion to HALS. Pure LLR and HALS were associated with less blood loss than conversion to OLR (p = 0.005 and p = 0.014, respectively). However, there was no significant difference in operation time, hospital stay, or severe complications.

CONCLUSIONS

The predictor of conversion to HALS was a tumor located in segments 7 or 8. The outcome of conversion to HALS was not inferior to pure LLR in terms of bleeding, operation time, hospital stay, or severe complication.

Laparoscopic liver resection with "ultrasonic scalpel mimic CUSA" technique

BACKGROUND

Liver parenchymal transection is the most critical step for laparoscopic liver resection (LLR). Ultrasonic scalpel (Harmonic) is a common used energy instrument in LLR; however, it is only recommended for superficial layer transection and the Cavitron Ultrasonic Surgical Aspirator (CUSA) is recommended for deep layer dissection. We herein introduce the "Harmonic mimic CUSA" technique for LLR.

METHODS

We retrospectively reviewed the medical records of the patients who underwent LLR using CUSA or the "Harmonic mimic CUSA" for parenchymal transection between July 2018 and October 2020 at West China Hospital of Sichuan University. Observation indicators included general demographic information, operative time, intraoperative blood loss, blood transfusion volume, complication rate, hospital stay, and the costs. Perioperative data was compared between the two groups by propensity score matching analysis (PSM).

RESULTS

A total of 298 patients, including 192 in Harmonic group and 106 in CUSA group, were enrolled in this study. After a 1:1 PSM, 99 patients using "Harmonic mimic CUSA" were matched with 99 patients via CUSA for parenchymal transection in LLRs. The Harmonic group had significantly less intraoperative blood loss (mean, 150 ml vs. 250 ml, P < 0.001), shorter operative time (mean 170 min vs. 250 min, P < 0.001) and less costs (mean 6723$ vs. 8307$, P < 0.001). The conversion to laparotomy, length of postoperative hospital stay, complications were comparable between the two groups. There perioperative mortality was nil.

CONCLUSION

The "Harmonic mimic CUSA" technique is safe, simple and feasible for LLR, which may be an alternative to CUSA for LLR.

Predictors of a difficult Pringle maneuver in laparoscopic liver resection and evaluation of alternative procedures to assist bleeding control

PURPOSE

To evaluate the predictors of a difficult Pringle maneuver (PM) in laparoscopic liver resection (LLR) and to assess alternative procedures to PM.

METHODS

Data from patients undergoing LLR between 2013 and 2020 were reviewed retrospectively. Univariate and multivariate analyses were performed and the outcomes of patients who underwent PM or alternative procedures were compared.

RESULTS

Among 106 patients who underwent LLR, PM could not be performed in 18 (17.0%) because of abdominal adhesions in 14 (77.8%) and/or collateral flow around the hepatoduodenal ligament in 5 (27.8%). Multivariate analysis revealed that Child-Pugh classification B (p = 0.034) and previous liver resection (p < 0.001) were independently associated with difficulty in performing PM in LLR. We evaluated pre-coagulation of liver tissue using microwave tissue coagulators, saline irrigation monopolar, clamping of the hepatoduodenal ligament using an intestinal clip, and hand-assisted laparoscopic surgery as alternatives procedures to PM. There were no significant differences in blood loss (p = 0.391) or transfusion (p = 0.518) between the PM and alternative procedures.

CONCLUSIONS

Child-Pugh classification B and previous liver resection were identified as predictors of a difficult PM in LLR. The alternative procedures were found to be effective.

Augmented Reality and Image-Guided Robotic Liver Surgery

Artificial intelligence makes surgical resection easier and safer, and, at the same time, can improve oncological results. The robotic system fits perfectly with these more or less diffused technologies, and it seems that this benefit is mutual. In liver surgery, robotic systems help surgeons to localize tumors and improve surgical results with well-defined preoperative planning or increased intraoperative detection. Furthermore, they can balance the absence of tactile feedback and help recognize intrahepatic biliary or vascular structures during parenchymal transection. Some of these systems are well known and are already widely diffused in open and laparoscopic hepatectomies, such as indocyanine green fluorescence or ultrasound-guided resections, whereas other tools, such as Augmented Reality, are far from being standardized because of the high complexity and elevated costs. In this paper, we review all the experiences in the literature on the use of artificial intelligence systems in robotic liver resections, describing all their practical applications and their weaknesses.

The Italian Consensus on minimally invasive simultaneous resections for synchronous liver metastasis and primary colorectal cancer: A Delphi methodology

At the time of diagnosis synchronous colorectal cancer, liver metastases (SCRLM) account for 15-25% of patients. If primary tumour and synchronous liver metastases are resectable, good results may be achieved performing surgical treatment incorporated into the chemotherapy regimen. So far, the possibility of simultaneous minimally invasive (MI) surgery for SCRLM has not been extensively investigated. The Italian surgical community has captured the need and undertaken the effort to establish a National Consensus on this topic. Four main areas of interest have been analysed: patients' selection, procedures, techniques, and implementations. To establish consensus, an adapted Delphi method was used through as many reiterative rounds were needed. Systematic literature reviews were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses instructions. The Consensus took place between February 2019 and July 2020. Twenty-six Italian centres participated. Eighteen clinically relevant items were identified. After a total of three Delphi rounds, 30-tree recommendations reached expert consensus establishing the herein presented guidelines. The Italian Consensus on MI surgery for SCRLM indicates possible pathways to optimise the treatment for these patients as consensus papers express a trend that is likely to become shortly a standard procedure for clinical pictures still on debate. As matter of fact, no RCT or relevant case series on simultaneous treatment of SCRLM are available in the literature to suggest guidelines. It remains to be investigated whether the MI technique for the simultaneous treatment of SCRLM maintain the already documented benefit of the two separate surgeries.

[Minimally invasive liver surgery]

Minimally invasive liver surgery is safe and can be performed with results practically equal to those in open surgery. There are different techniques of parenchyma dissection and hemostasis available for the safe performance of minor and major resections, both laparoscopically and robotics based. Due to its technical options robotics-based surgery is a further development of laparoscopy. Expertise in minimally invasive and in liver surgery are essential prerequisites.

Robotic ICG guided anatomical liver resection in a multi-centre cohort: an evolution from "positive staining" into "negative staining" method

BACKGROUND

Laparoscopic major anatomical liver resection is challenging. The robotic liver resection (RLR) approach, with Firefly indocyanine green (ICG) imaging, was proposed to overcome the limitations of laparoscopy. The aim of this multi-centre international study was to evaluate the use of Firefly ICG imaging in anatomical RLR.

METHODS

A retrospective study of consecutive patients undergoing RLR anatomical resection with intra-operative ICG administration from January 2015 to July 2018 were enrolled. Patients who underwent simultaneous or en-bloc resections of other organs were excluded.

RESULTS

A total of 52 patients were recruited of which 32 patients were healthy donors, 17 with malignancy and 3 for benign conditions. 12 patients had cirrhosis. 28 patients underwent a right hepatectomy (53.8%) with left hepatectomy performed with 18 patients. 40 patients underwent negative staining and 12 patients via direct portal vein injection for positive staining. ICG demarcation line was visualized in 43 patients and was clearer than the ischaemic demarcation line in 29 patients. All resections for malignancy had clear margins. There were no 30-day/inpatient mortalities.

CONCLUSION

Robotic ICG guided hepatectomy technique for anatomical liver resection is safe, feasible and has the benefit for improved visualization in healthy donors and cirrhotic patients.

Laparoscopic hepatectomy versus open hepatectomy for hepatocellular carcinoma: A propensity case-matched analysis of the long-term survival

Backgrounds/Aims

Despite the widespread popularity of laparoscopic surgery, laparoscopic liver resection (LLR) remains in evolution. This study aimed to compare the long-term outcomes for patients undergoing laparoscopic versus open hepatectomy for hepatocellular carcinoma (HCC) ≤7 cm.

Methods

Patients diagnosed with HCC treated by hepatectomy from October 2000 to May 2019 were included. Excluding tumors larger than 7 cm, 1:2 propensity score matching was performed between laparoscopic and open hepatectomies. The perioperative outcomes, 5-year overall survival (OS) and disease-free survival (DFS) of the two groups were compared.

Results

Forty-five patients who underwent LLR were matched to 90 open hepatectomy (OH) during the same period. LLR group had shorter median hospital stay (5 days vs. 9 days, p=0.00) but required longer operative time (326.0 minutes vs. 272.5 minutes, p=0.018) than the OH group. The 5-year overall survival was better in the LLR group (84.9% vs. 61.1%; p=0.036), though there was no significant difference in the 5-year disease free survival (20.0% vs. 22.2%, p=0.613). The rate of R0 resection was comparable between the 2 groups with a slightly better margin distance in the LLR (5 mm vs. 3 mm, p=0.043).

Conclusions

Laparoscopic liver resection is safe and feasible for cirrhotic patients with HCC size up to 7 cm. It has better short-term outcomes and comparable perioperative blood loss and complication rates. The resection margin is not jeopardized and the 5-year overall and disease-free survivals are comparable with the open group.

Pure Laparoscopic Hepatectomy for Tumors Close to the Major Hepatic Veins: Intraparenchymal Identification of the Major Hepatic Veins using the Ventral Approach

BACKGROUND

Laparoscopic hepatectomy for tumors close to the major hepatic veins (HVs) is a technically demanding procedure that is relatively contraindicated. We investigated this surgical technique and the outcomes of intraparenchymal identification of the major HVs using the ventral approach in pure laparoscopic hepatectomy for tumors close to the major HVs.

METHODS

In the present study, tumors < 10 mm from the major HVs were defined as lesions in proximity to the major HVs. The cranio-ventral part of the liver parenchyma along the targeted major hepatic veins was opened to facilitate an open cutting plane. After a wide exposure of the surgical plane, the targeted major HVs were identified.

RESULTS

Thirteen patients with tumors close to the major HVs underwent laparoscopic hepatectomy. The median operative time was 260 min (range, 160-410 min), while the intraoperative blood loss was 100 mL (range, 30-310 mL). The median Pringle maneuver time was 45 min (range, 40-75 min). The median tumor size was 50 mm (range, 17-140 mm), and the median tumor margin was 4 mm (range, 0-10 mm). Three patients (23.1%) experienced minor postoperative complications. The median postoperative hospital stay was 7 days (range, 4-25 days).

CONCLUSIONS

Pure laparoscopic hepatectomy for tumors close to the major HVs is technically feasible in selected patients. Intraparenchymal identification of the major HVs using the ventral approach achieves transection plane accuracy and avoids inadvertent injury to the major HVs.

Landmarks to identify segmental borders of the liver: A review prepared for PAM-HBP expert consensus meeting 2021

BACKGROUND

In preparation for the upcoming consensus meeting in Tokyo in 2021, this systematic review aimed to analyze the current available evidence regarding surgical anatomy of the liver, focusing on useful landmarks, strategies and technical tools to perform precise anatomic liver resection (ALR).

METHODS

A systematic review was conducted on MEDLINE/PubMed for English articles and on Ichushi database for Japanese articles until September 2020. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN).

RESULTS

A total of 3169 manuscripts were obtained, 1993 in English and 1176 in Japanese literature. Subsequently, 63 English and 20 Japanese articles were selected and reviewed. The quality assessment of comparative series and case series was revealed to be usually low; only six articles were qualified as high quality. Forty-two articles focused on analyzing intersegmental/sectional planes and their relationship with specific hepatic landmark veins. In 12 articles, the authors aimed to investigate liver surface anatomic structures, while 36 articles aimed to study technological tools and contrast agents for surgical segmentation during ALR. Although Couinaud's classification has remained the cornerstone in daily diagnostic/surgical practices, it does not always portray the realistic liver segmentation and there has been no standardization on which a single strategy should be followed to perform precise ALR.

CONCLUSIONS

A global consensus should be pursued in order to establish clear guidelines and proper recommendations to perform ALR in the era of minimally invasive surgery.

Efficiency of a radiofrequency sealer (Aquamantys) for parenchymal transection during laparoscopic hepatectomy

INTRODUCTION

The methods of liver parenchymal transection vary across institutions. In this study, we used a radiofrequency (RF) sealer (Aquamantys) as a hemostatic device during laparoscopic liver transection; we also evaluated the usefulness of RF sealers.

METHODS

From April 2016 to May 2019, 113 consecutive laparoscopic hepatectomy patients, excluding patients with combined resection of other organs, were examined. Patient characteristics, operative factors, and postoperative complications were compared between the Cavitron ultrasonic surgical aspirator (CUSA) + soft coagulation system (VIO) group; (n = 32) and the CUSA + Aquamantys group; (n = 81). The former underwent liver transection by CUSA and VIO from April 2016 to March 2017, while the latter underwent liver transection using CUSA and Aquamantys from April 2017 to May 2019.

RESULTS

The median difficulty score was significantly higher in the CUSA + VIO group (5.5 points vs 5.0 points; P = .04). Blood loss per unit area and the liver parenchymal transection speed were not significantly different between the groups. After propensity score matching, blood loss per unit area was similar between the groups, but the parenchymal transection speed of the CUSA + Aquamantys group was significantly higher (0.92 cm² /min vs 0.64 cm² /min; P = .017). Postoperative complications were similar between the groups.

CONCLUSION

In laparoscopic hepatectomy, hemostasis of the transection plane with an RF sealer did not reduce blood loss during parenchymal transection. However, the liver parenchymal transection speed was increased.

The usefulness of the totally intra-corporeal pringle maneuver with Penrose drain tube during laparoscopic left side liver resection

Backgrounds/Aims

The Pringle maneuver is generally performed to reduce the amount of blood loss during hepatic resection. During laparoscopic liver resection, the Pringle maneuver can be used in several ways. We have developed a new Pringle maneuver (PM) with Penrose drain tube to sufficiently control blood loss during laparoscopic liver resection. This study was performed to determine the safety and outcome during laparoscopic left-sided hepatectomy performed using this new method.

Methods

We describe the technique and results of the left-sided liver resection with totally intracorporeal PM with Penrose drain tube. We performed 37 laparoscopic left-sided hepatic resections with (PM group) or without the Penrose PM (No PM group). We retrospectively compared the short-term operative outcome between the No PM group (n=12) and the PM group (n=25) during laparoscopic left-sided liver resection.

Results

Median PM duration was 34.3 min. The median duration of the surgery using the totally intracorporeal PM with Penrose drain tube was 174 min, while the surgical duration required for resection without the PM was 156 min. The median volume of operative blood loss was lower in the PM group than in the No PM group (No PM group (341 ml) vs. PM group (165 ml)). There was no postoperative mortality and no open conversion.

Conclusions

The totally intracorporeal PM with Penrose drain tube for laparoscopic hepatectomy is safe, reproducible, and can facilitate liver dissection during left-sided liver resection.

Robotic hepatic parenchymal transection: a two-surgeon technique using ultrasonic dissection and irrigated bipolar coagulation

Liver transection is the most challenging part of hepatectomy due to the risk of hemorrhage which is associated with postoperative morbidity and mortality and reduced long-term survival. Parenchymal ultrasonic dissection (UD) with bipolar coagulation (BPC) has been widely recognized as a safe, effective, and standard technique during open and laparoscopic hepatectomy. We here introduce our technique of robotic liver transection using UD with BPC and report on short-term perioperative outcomes. From a single-institution prospective liver surgery database, we identified patients who underwent robotic liver resection. Demographic, anesthetic, perioperative, and oncologic data were analyzed. Fifty patients underwent robotic liver resection using UD and BPC for liver malignancies (n = 42) and benign lesions (n = 8). The median age of the patients was 67 years and 28 were male. According to the difficulty scoring system, 60% (n = 30) of liver resection were considered difficult. Three cases (6%) were converted to open surgery. The median operative time was 240 min, and the median estimated blood loss was 200 ml; 2 patients required operative transfusions. The overall complication rate was 38% (grade I, 29; grade II, 15; grade III, 3; grade IV, 1). Seven patients (14%) experienced biliary leakage. The median length of hospital stay post-surgery was 7 (range 3-20) days. The R0 resection rate was 92%. Robotic parenchymal transection using UD and irrigated BPC appears a simple, safe, and effective technique. However, our results must be confirmed in larger series or in randomized controlled trials.

Clamp-Crush Technique for Laparoscopic Liver Resection

Liver parenchymal transection is the most important process in laparoscopic liver resection (LLR). Various surgical methods and devices for LLR have been applied including the cavitron ultrasonic surgical aspirator, ultrasonic scalpel, and staplers. Very few reports have investigated the clamp--crush technique for LLR.1^,2 Current study shows a clamp-crush technique for LLR and evaluates its perioperative outcomes. The clamp-crush technique was performed using simple forceps and the Pringle maneuver under a low central venous pressure. The vessels that remained after crushing were clipped if they were thick; or removed with an ultrasonic cutting-coagulation system if they were thin. Sixty-one LLRs were performed using the clamp-crush technique. Pathological cirrhosis was observed in 22 patients (36.0%). The types of resection were as follows: 31 wedge resections (50.8%), 11 segmentectomies (19.0%), 9 sectionectomies (14.8%), and 10 hemihepatectomies (16.4%). The intraoperative blood loss was 62 ml; the surgical duration was 272 min. The postoperative major complication (Clavien-Dindo ≥ IIIa) rate was 4.9%. The median hospital stay was 8 days (range = 4-53 days). A 76-year-old female underwent right LLR for a 9-cm HCC. The right hepatic artery and portal vein were dissected separately. After mobilizing the liver, parenchymal transection was performed using the clamp-crush technique. The middle hepatic vein was totally exposed. Intraoperative blood loss was 32 ml and the surgical duration was 5 h 32 min with no postoperative complications. The clamp-crush technique is safe and feasible for LLR and could contribute to quick parenchymal transection and flattening of the transection plane.

Techniques for laparoscopic liver parenchymal transection

Laparoscopic liver surgery has gained wide acceptance resulting in a paradigm shift of liver surgery. Technical innovations and accumulation of surgeon's experience have allowed laparoscopic liver resection (LLR) to become an effective procedure with favorable peri- and post-operative outcomes. Through the overall process of LLR, liver parenchymal transection remains the most critical step with the aim of minimizing blood loss and secures the appropriate cutting line, i.e., securing major vessels and obtaining adequate surgical margin clearance for malignancies. Multiple preoperative imaging modalities and intraoperative ultrasonography findings may contribute to the best determination of the appropriate cutting line during the LLR; however, technical expertise in minimizing and controlling bleeding during liver parenchymal transection is still a challenge for safe LLR, and therefore represents a major concern for hepatobiliary surgeons. Along with the historical fact that the technique of liver parenchymal transection itself is chosen according to surgeon's preference and "savoir-faire", the best technical modality in laparoscopic liver parenchymal transection remains to be determined. However, better understanding the technical issue may serve a contribution to the standardization of LLR. This review article therefore focuses on the technical aspects of the laparoscopic liver parenchymal transection.

Novel biodegradable magnesium alloy clips compared with titanium clips for hepatectomy in a rat model

Background

The use of surgical metal clips is crucial for ligating vessels in various operations. The currently available metal clips have several drawbacks; they are permanent and interfere with imaging techniques such as computed tomography (CT) or magnetic resonance (MR) imaging and carry the potential risk of endo-clip migration. We recently developed a novel magnesium (Mg) alloy for biodegradable clips that reduces artifacts on CT imaging. This study aimed to examine the tolerance, biodegradability, and biocompatibility of the Mg alloy clips compared with those of standard titanium (Ti) clips in hepatectomy.

Methods

Thirty Wistar rats were divided into two groups based on the clip used (groups A and B). The vascular pedicle, including hepatic artery, portal vein, bile duct, and hepatic vein of the left lateral lobe, was ligated with the Ti clip in group A or the Mg alloy clip in group B, and then the left lateral lobe was removed. The rats were sacrificed at 1, 4, 12, 24, and 36 weeks after surgery. Clinical and histological evaluations were performed. Absorption rate was calculated by measuring the clip volume.

Results

Although the Mg alloy clips showed biodegradability over time, there were no significant differences in the serum concentration of Mg between the two groups. The remaining volume ratio of Mg alloy clips was 95.5, 94.3, 80.0, 36.2, and 16.7% at 1, 4, 12, 24, and 36 weeks, respectively. No side effects occurred. Most of the microscopic changes were similar in both groups.

Conclusions

The new biodegradable Mg alloy clips are safe and feasible in vessel ligation for hepatectomy in a rat model and reduce artifacts in CT imaging compared with the standard Ti clips.

Our experience of repeat laparoscopic liver resection in patients with recurrent hepatocellular carcinoma

BACKGROUND

Repeat liver resection is an effective treatment approach for patients with recurrent hepatocellular cell carcinoma (HCC). However, the surgical feasibility and oncological significance of repeat laparoscopic liver resection (r-LLR) remain unproven. This study evaluates and compares the clinical outcomes of non-anatomic r-LLR applied towards recurrent HCC, with those of primary LLR (p-LLR) for primary HCC.

METHODS

This retrospective study reports 104 patients with HCC, treated with LLR between 2014 and 2018. Twenty eight of these patients underwent r-LLR for recurrent HCC. The clinical and surgical variables were reviewed for all cases.

RESULTS

The analysis was limited to non-anatomic resection across both groups (r-LLR: 89% (25/28) vs. p-LLR: 80% (61/76)). There were no statistically significant differences about patient background between the two groups, with the exception of Child-Pugh classification. r-LLR surgical techniques included single-site laparoscopic adhesiolysis (32%, 8/25), Pringle maneuver (8%, 2/25), and crush-clamp method using BiClamp for hepatic parenchymal transection (72%, 18/25). No severe postoperative complications were observed in the r-LLR group. Postoperative hospital stays and procedure-related postoperative survival were similar for both groups.

CONCLUSIONS

Non-anatomical r-LLR renders comparable surgical and oncological outcomes. Our data suggest that non-anatomical r-LLR is a safe and feasible therapeutic approach to recurrent HCC.

Comparison of Outcomes Between Open Major Hepatectomy Using CUSA and Laparoscopic Major Hepatectomy Using "Lotus" Liver Blade. A Propensity Score Matched Analysis

Introduction: Evolution in laparoscopic liver surgery during the past two decades is an indisputable fact. According to the second international consensus conference for laparoscopic liver resection held in Morioka, Japan in 2014 major resections are still regarded as innovative procedures in the exploration phase. On this basis, our study aims to explore the efficacy and safety of laparoscopic vs. open major liver resection and therefore increase the existing evidence on major laparoscopic liver surgery. Methods: All consecutive patients who underwent major liver resection, open and laparoscopic from January 2016 to May 2018 were identified from our prospectively maintained database. Propensity score matching analysis was performed using R statistical tool in SPSS to isolate matched open and laparoscopic cases which were compared for intraoperative and postoperative short-term outcomes. Lotus ultrasonic energy device was used for parenchymal transection in laparoscopic cases vs. CUSA in open procedures. Results: Propensity score matching analysis was performed on 82 consecutive patients (61 open and 21 laparoscopic major hepatectomies) resulting in 40 matched patients, 20 in each group. The mean total duration of surgery and duration of parenchymal transection were slightly longer in the laparoscopic group (p = 0.419, p = 0.348). There was no difference in the intraoperative and postoperative transfusion rates. Patients after laparoscopic surgery were discharged 2 days earlier on average (p = 0.310). No difference was observed in complication rates and mortality. Conclusion: Our data did not reveal inferiority of the laparoscopic major hepatectomy vs. the open approach in any parameter compared. The use of the Lotus ultrasonic energy device appeared to be efficient and safe for parenchymal transection in the laparoscopic procedures.

Pushing the limits of liver surgery for colorectal liver metastases: Current state and future directions

Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery. Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover, changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.

Feasibility Study of a Newly Developed Hybrid Energy Device Used During Laparoscopic Liver Resection in a Porcine Model

BACKGROUND

Although various devices have been clinically used for laparoscopic liver resection (LLR), the best device for liver parenchymal transection remains unknown. Olympus Corp (Tokyo, Japan) developed a laparoscopic hybrid pencil (LHP) device, which is the first electric knife to combine ultrasound and electric energy with a monopolar output. We aimed to evaluate the feasibility of using the LHP device and to compare it with the laparoscopic monopolar pencil (LMP) and laparoscopic ultrasonic shears (LUS) devices for LLR in a porcine model.

METHODS

Nine male piglets underwent laparoscopic liver lobe transections using each device. The operative parameters were evaluated in the 3 groups (n = 24 lobes) during the acute study period. The imaging findings from contrast-enhanced computed tomography and histopathological findings of autopsy on postoperative day 7 were compared among groups (n = 6 piglets) during the long-term study.

RESULTS

The transection time was shorter ( P = .001); there was less blood loss ( P = .018); and tip cleaning ( P < .001) and instrument changes were less often required ( P < .001) in the LHP group than in the LMP group. The LHP group had fewer instances of bleeding ( P < .001) and coagulator usage ( P < .001) than did the LUS group. In the long-term study, no postoperative adverse events occurred in the 3 groups. The thermal spread and depth of the LHP device were equivalent to those of the LMP and LUS devices (vs LMP: P = .226 and .159; vs LUS: P = 1.000 and .574).

CONCLUSIONS

The LHP device may be an efficient device for LLR if it can be applied to human surgery.

Laparoscopic liver resection: a review of current indications and surgical techniques

Laparoscopic liver resection (LLR) has been the most impressive development in the field of liver surgery in recent two decades. Technical innovations and experience accumulation have made LLR a safe and effective procedure with faster postoperative recovery. Despite the fast spreading of the procedure, details regarding the indications, oncological outcomes and technical essentials were still disputable. To address these issues, two international consensus conferences were hold to update the knowledge in this field. The statements of the both conferences were not conclusive and more high-quality researches are required. In this article, we reviewed the development and the current state of LLR. Indications, outcomes, surgical techniques and devices used in LLR were also discussed.

[Technical aspects of laparoscopic liver surgery : Transfer from open to laparoscopic liver surgery]

BACKGROUND

Laparoscopic surgery has become the standard for most visceral surgery procedures in many hospitals. Now, liver resections are also being increasingly carried out laparoscopically. The advantages of the laparoscopic technique have been demonstrated in numerous case series and in a recent randomized controlled trial.

AIMS

The aim of this review article is to present the available techniques for laparoscopic liver surgery (LLS).

METHODS

The technical variations reported in the literature as well as the own experience with LLS are reported.

RESULTS

Optimal patient and trocar positions are crucial for successful LLS and they are chosen according to the planned type of liver surgery: the literature offers several options in particular for surgery of the cranial and dorsal liver segments. As for open liver surgery, a restrictive volume management and the application of the Pringle maneuver are helpful to reduce intraoperative blood loss in LLS. In addition, several dissection techniques have been adopted from open liver surgery. The Cavitron Ultrasound Surgical Aspirator (CUSA™) is particularly suitable for parenchymal dissection close to major vascular structures, since it guarantees a meticulous parenchymal dissection with minimal vascular injuries.

CONCLUSION

The developments of minimally invasive surgery nowadays allow complex liver resections, which can mostly be performed comparable to open liver surgery. Hopefully, minimally invasive liver surgery will further develop in Germany in the near future, since it offers several advantages over open liver surgery.

Impact of Ultrasonic Scalpels for Liver Parenchymal Transection on Postoperative Bleeding and Bile Leakage

BACKGROUND/AIM

Novel techniques for liver parenchymal transection have emerged and they are available to the hepatobiliary surgeon. The aim of our study was to compare two types of ultrasonic scalpels (Lotus and Harmonic) and examine how they perform either alone or in combination with the SonaStar ultrasonic surgical aspiration system regarding postoperative bleeding and bile leakage.

PATIENTS AND METHODS

Our prospectively maintained database of patients who underwent liver resections in our Department was reviewed. One hundred and two patients with solid liver lesions underwent liver resection by a senior hepatobiliary surgeon in our department during a period of 51 months. They were divided into four groups according to the devices that were used for liver parenchymal transection.

RESULTS

Patients were divided into the following groups: group 1: Lotus, 32 patients (31.4%); group 2: Lotus+SonaStar, 27 patients (26.5%); group 3: Harmonic, 27 patients (26.5%); group 4: Harmonic+SonaStar, 16 patients (15.7%). There were 5 cases of postoperative bleeding and 9 cases of postoperative bile leakage. No significant difference was found concerning postoperative bleeding (group 1: 2/32; 6.3%, group 2: 2/27; 7.4%, group 3: 0/27; 0%, group 4: 1/16; 6.3%) (p=0.577). Furthermore, no actual difference was detected in terms of postoperative bile leakage (group 1: 2/32; 6.3%, group 2: 3/27; 11.1%, group 3: 3/27; 11.1%, group 4: 1/16; 6.3%) (p=0.866).

CONCLUSION

Both Lotus and Harmonic ultrasonic scalpels provide adequate and similar results concerning postoperative hemorrhage and cholorrhea.

Intermittent Pringle Versus Continuous Half-Pringle Maneuver for Laparoscopic Liver Resections of Tumors in Segment 7

Segment 7 is considered an unfavorable portion for laparoscopic hepatectomy because of technical difficulties in exposure and controlling bleeding. We compared intermittent Pringle with continuous half-Pringle maneuver in laparoscopic liver resections of tumors in segment 7. A retrospective analysis was conducted in a total of 36 consecutive patients with tumors in segment 7 undergoing laparoscopic liver resections between July 2011 and February 2016 (16 in the Pringle group versus 20 in the half-Pringle group). The two groups were well matched in baseline characteristics. The operative time (274.5 ± 34.3 versus 237.6 ± 41.8 min), overall declamping time (28.4 ± 8.6 versus 2.3 ± 2.5 min), and ischemic duration (69.7 ± 16.5 versus 52.7 ± 13.2 min) were significantly longer in the Pringle group (P < 0.05). The amount of intraoperative blood loss (612.5 ± 222.3 versus 417.4 ± 163.8 mL) and transfusion (335.2 ± 58.7 versus 224.8 ± 76.2 mL) was significantly greater in the Pringle group (P < 0.05). The Pringle group was associated with significantly lower postoperative albumin and higher C-reactive protein levels on postoperative days 1, 3, and 7 (P < 0.05). Laparoscopic hepatectomy for tumors in segment 7 can be performed safely and effectively with successful exposure of surgical field and proper hepatic blood flow occlusion. Continuous half-Pringle maneuver offers the advantages of less operative time and blood loss, less injury, and better recovery.

Comprehensive evaluation of liver resection procedures: surgical mind development through cognitive task analysis

Background

Liver resection is a complex procedure for trainee surgeons. Cognitive task analysis (CTA) facilitates understanding and decomposing tasks that require a great proportion of mental activity from experts.

Methods

Using CTA and video-based coaching to compare liver resection by open and laparoscopic approaches, we decomposed the task of liver resection into exposure (visual field building), adequate tension made at the working plane (which may change three-dimensionally during the resection process), and target processing (intervention strategy) that can bridge the gap from the basic surgical principle.

Results

The key steps of highly-specialized techniques, including hanging maneuvers and looping of extra-hepatic hepatic veins, were shown on video by open and laparoscopic approaches.

Conclusions

Familiarization with laparoscopic anatomical orientation may help surgeons already skilled at open liver resection transit to perform laparoscopic liver resection smoothly. Facilities at hand (such as patient tolerability, advanced instruments, and trained teams of personnel) can influence surgical decision making. Application of the rationale and realizing the interplay between the surgical principles and the other paramedical factors may help surgeons in training to understand the mental abstractions of experienced surgeons, to choose the most appropriate surgical strategy effectively at will, and to minimize the gap.

Topical hemostasis in laparoscopic surgery

A major goal during any surgical intervention is minimization of blood loss, which reduces the need for blood transfusion. In open surgery, the possibility for the surgeon to use the hands directly in contact with the bleeding tissues for hemostasis, makes mechanical methods, such as compression, ligatures or sutures, important to achieve proper hemostasis. In laparoscopic surgery, where the intervention is performed by means of small incisions through which the surgeon's hand cannot directly achieve the tissues, the problem of hemostasis is critical and needs more attention. Either in open or in laparoscopic surgery, significant bleeding during surgery is controlled through vessel ligation, suturing, and electrocautery. Topical hemostatic agents are useful adjuncts to surgical hemostasis for controlling non-specific bleeding. The introduction of different devices and topical agents has made possible to perform more complex interventions also in laparoscopy. The Authors discuss about the type, the field of application, the side effects of the hemostatic devices and of the topical hemostatic agents.

Setting up a robotic hepatectomy program: a Western-European experience and perspective

Currently the majority of liver resections are performed via open resection. Nevertheless, minimally invasive liver surgery is gaining ground and conventional laparoscopy has proven to be beneficial in different fields of liver surgery compared to open resections. Still, conventional laparoscopy has a few downsides, from which straight instruments, 2-dimensional view and awkward ergonomics are the most obvious. The robotic surgical system is developed to overcome these limitations. It offers several advantages over conventional laparoscopy to optimize conditions in minimally invasive surgery: instruments are wristed with a wide range of motion and the view is 3-dimensional and magnified. With instruments with a greater range of motion than in laparoscopic surgery, the use of a robotic system potentially broadens indications for minimally invasive liver resection. Here, we discuss the steps of setting up a robotic hepatectomy program against the background of the initial experience at our institution.

Feasibility and Technique for Transvaginal Natural Orifice Transluminal Endoscopic Surgery Liver Resection: A Porcine Model

INTRODUCTION

Natural orifice transluminal endoscopic surgery (NOTES) is a challenging minimally invasive procedure. Although laparoscopic techniques for liver resection are gaining acceptance worldwide, few studies have investigated NOTES liver resection. We used a porcine model to assess the feasibility and safety of transvaginal NOTES liver resection (TV NOTES LR).

MATERIALS AND METHODS

Nine female pigs underwent TV NOTES LR. A nonsurvival acute porcine model with general anesthesia was used in all cases. Using hybrid NOTES technique, we placed only 1 umbilical 12-mm umbilical trocar in the abdominal wall, which was used to create pneumoperitoneum. A laparoscope was then advanced to obtain intra-abdominal visualization. A 15-mm vaginal trocar was inserted under direct laparoscopic vision, and a flexible endoscope was introduced through the vaginal trocar. A long, flexible grasper and endocavity retractor were used to stably retract the liver. The liver edge was partially transected using energy devices inserted through the umbilical trocar. To transect the left lateral lobe, a flexible linear stapler was inserted alongside the vaginal trocar. A specimen extraction bag was deployed and extracted transvaginally. Blood loss, bile leakage, operative time, and specimen size were evaluated. Necropsy studies were performed after the procedures.

RESULTS

Eighteen transvaginal NOTES partial liver resections and 4 transvaginal NOTES left lateral lobectomies were successfully performed on 9 pigs. Mean operative time was 165.8 minutes, and mean estimated blood loss was 76.6 mL. All TV NOTES LRs were performed without complications or deaths. Necropsy showed no bile leakage from remnant liver.

CONCLUSIONS

Our porcine model suggests that TV NOTES LR is technically feasible and safe and has the potential for clinical use as a minimally invasive alternative to conventional laparoscopic liver resection.

Selective Hemihepatic Vascular Occlusion Versus Pringle Maneuver in Hepatectomy for Primary Liver Cancer

Background

This study was conducted to compare the clinical effects of two techniques used for inflow occlusion during hepatectomy (selective hemihepatic vascular occlusion vs. Pringle maneuver) for the treatment of primary liver cancer.

Material/Methods

A total of 63 patients with primary hepatocellular carcinoma who underwent hepatectomy during June 2006 and June 2011 were included in this retrospective study. A total of 26 patients in group A accepted selective hemihepatic vascular occlusion, and 37 patients in group B underwent the Pringle maneuver during hepatectomy. The intraoperative conditions, postoperative liver function recovery, and complication rates were compared between these two groups.

Results

There were no significant differences in intraoperative blood loss, blood transfusion, occlusion time, and postoperative complication rates between group A and group B (P>0.05). However, postoperative serum levels of alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), and albumin (ALB) in group A were significantly lower than those in group B (P<0.05). Moreover, there were noteworthy differences in peripheral artery pressure and sphygmus (P<0.05).

Conclusions

During hepatectomy, selective hemihepatic vascular occlusion benefits the patients with primary hepatocellular carcinoma by reducing the hepatic damage and improving postoperative hepatic function recovery, compared with the Pringle maneuver.

Evolution and revolution of laparoscopic liver resection in Japan

Due to important technological developments and improved endoscopic techniques, laparoscopic liver resection (LLR) is now considered the approach of choice and is increasingly performed worldwide. Recent systematic reviews and meta‐analyses of observational data reported that LLR was associated with less bleeding, fewer complications, and no oncological disadvantage; however, no prospective randomized trials have been conducted. LLR will continue to evolve as a surgical approach that improves patient's quality of life. LLR will not totally supplant open liver surgery, and major LLR remains to be technically challenging procedure. The success of LLR depends on individual learning curves and adherence to surgical indications. A recent study proposed a scoring system for stepwise application of LLR, which was based on experience at high‐volume Japanese centers. A cluster of deaths after major LLR was sensationally reported by the Japanese media in 2014. In response, the Japanese Society of Hepato‐Biliary‐Pancreatic Surgery conducted emergency data collection on operative mortality. The results demonstrated that mortality was not higher than that for open procedures except for hemi‐hepatectomy with biliary reconstruction. An online prospective registry system for LLR was established in 2015 to be transparent for patients who might potentially undergo treatment with this newly developed, technically demanding surgical procedure.

Central Venous Pressure Drop After Hypovolemic Phlebotomy is a Strong Independent Predictor of Intraoperative Blood Loss During Liver Resection

BACKGROUND

Intraoperative hypovolemic phlebotomy (HP) has been suggested to reduce central venous pressure (CVP) before hepatectomy. This study aimed to analyze the impact of CVP drop after HP on intraoperative blood loss and postoperative renal function.

METHODS

A retrospective review of a prospective database including 100 consecutive patients (43 males and 57 females; mean age, 65 years; range 23-89 years) undergoing liver resection with HP was performed. The primary outcome variable was estimated blood loss (EBL), and the secondary outcome was postoperative serum creatinin (Scr). A multivariate linear regression analysis was performed to identify predictors of intraoperative blood loss.

RESULTS

The median CVP before blood salvage was 8 mmHg (range 4-30 mmHg). The median volume of hypovolemic phlebotomy was 400 ml (range 200-1000 ml). After HP, CVP decreased to a median of 3 mmHg (range -2 to 16 mmHg), resulting in a median CVP drop of 5.5 mmHg (range 2-14 mmHg). The median EBL during liver resection was 165 ml (range 0-800 ml). The median preoperative serum creatinin (Scr) was 0.82 g/dl (range 0.5-1.74 g/dl), and the postoperative Scr on day 1 was 0.74 g/dl (range 0.44-1.68 g/dl). The CVP drop was associated with EBL (P < 0.001). There was no significant impact of CVP drop on postoperative Scr.

CONCLUSION

A CVP drop after HP is a strong independent predictor of EBL during liver resection. The authors advocate the routine use of HP to reduce perioperative blood loss and transfusion rates in liver surgery. As a predictive tool, CVP drop might help surgeons decide whether a laparoscopic approach is safe.

Application of stapling devices in liver surgery: Current status and future prospects

The liver is a vascular-rich solid organ. Safe and effective dissection of the vessels and liver parenchyma, and control of intraoperative bleeding are the main concerns when performing liver resection. Several studies have confirmed that intraoperative blood loss and postoperative transfusion are predictors of postoperative morbidity and mortality in liver surgery. Various methods and instruments have been developed during hepatectomy. Stapling devices are crucial for safe and rapid anastomosis. They are used to divide hepatic veins and portal branches, and to transect liver parenchyma in open liver resection. In recent years, laparoscopic liver surgery has developed rapidly, and is now preferred by many surgeons. Stapling devices have also been gradually introduced in laparoscopic liver surgery, from dividing vascular and biliary structures to parenchymal transection. This may be because staplers make manipulation more simple, rapid and safe. Even in single incision laparoscopic surgery, which is recognized as a new minimally invasive technique, staplers are also utilized, especially in left lateral hepatectomy. For safe application of stapling devices in liver surgery, more related designs and modifications, such as application of a suitable laparoscopic articulating liver tissue crushing device, a staple line reinforcement technique with the absorbable polymer membrane or radiofrequency ablation assistance, are still needed. More randomized studies are needed to demonstrate the benefits and find broader indications for the use of stapling devices, to help expand their application in liver surgery.

What has changed after the Morioka consensus conference 2014 on laparoscopic liver resection?

The 2(nd) International Consensus Conference on Laparoscopic Liver Resection (ICCLLR) was held 4(th)-6(th) October, 2014, in Morioka, Japan. The level of evidence appears to be low in the field of laparoscopic liver resection (LLR) to create strong recommendations. Therefore, an independent jury-based consensus model was applied to better define the current role of LLR and to develop internationally accepted recommendations. The three-day conference was very intense with full of insightful discussions on assessment of LLR and its future directions. The jury drew the statements based on the presentations and documents prepared by the expert. LLR is theoretically superior to open liver resection (OLR) because the laparoscope allows better exposure with a magnified view, and the pneumoperitoneum pressure reduces hepatic vein bleeding from the cut surface. During the ICCLLR, we shared these theoretical advantages in LLR and the conceptual change of liver resection. After the ICCLLR, a couple of important studies have been published to prove this theoretical superiority of LLR over OLR in short-term outcomes without deteriorating long-term outcomes. Another new concept was proposed at the ICCLLR: parenchyma sparing (limited) anatomical resection. Review of the literature supports anatomical resection with parenchyma sparing strategy for LLR irrespective of hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). Just after the ICCLLR, sensational news of clustered mortality after LLR was reported in the Japanese media and they impacted on daily practice of LLR in Japan. The most important message from the ICCLLR is to protect patients from this new surgical procedure. The ICCLLR recommended three actions for the protection of patients: (I) prospective reporting registry for transparency; (II) a difficulty scoring system to select patients; (III) creation of a formal structure of education. The online prospective registry system including items to calculate the difficulty score has been created in Japan after the ICCLLR for the safe development of LLR.

An ex vivo liver training model continuously perfused to simulate bleeding for suture skills involved in laparoscopic liver resection: development and validity

BACKGROUND

Suture skills are essential to laparoscopic liver resection. The current suture training models are not ideal enough. The aim of this study is to develop and verify a highly simulated-bleeding continuously perfused training model (CPTM) and to evaluate its training efficacy.

METHODS

CPTM was constructed using fresh lamb liver whose portal veins were perfused with red-dyed liquid gelatin. Construct validity of CPTMs was tested in 33 participants with three levels of laparoscopic experience (experts, intermediates, and novices) who were demanded to finish one superficial stitch and one deep stitch for suture hemostasis on CPTMs. The CPTMs were also evaluated by the experts. CPTMs were compared with dry box training models (DBTMs) regarding training efficacy among the novices who were assigned to DBTM and CPTM groups to, respectively, complete a 10-day training on CPTMs or DBTMs. Before and after their assignments, their superficial stitches were assessed by completion time, suture accuracy, and suture knot performance while their deep stitches by completion time and bleeding control.

RESULTS

CPTM proved to be construct valid by both superficial and deep stitches. Significant differences were found regarding completion time (763, 271, 174 s), suture accuracy (4.4, 1.8, 0.2 mm), and suturing knot performance (12.1, 21.5, 22.0) for superficial stitches (p < 0.001), as well as regarding completion time (807, 423, 277 s) for deep stitches (p < 0.001). Positive comments were given by all experts. CPTMs helped novices to acquire laparoscopic suture skills. Their training efficacy was significantly better than that of DBTMs (p < 0.05). Learning curves of CPTM group plateaued at the sixth round for superficial stitches and at the seventh round for deep stitches.

CONCLUSION

CPTM offers trainees a highly simulated-bleeding means to acquire advanced laparoscopic suture skills. The suture skills learned on CPTMs may improve significantly at the seventh round.

Laparoscopic liver resection for hepatocellular carcinoma with cirrhosis in a single institution

BACKGROUND

In a statement by the second International Consensus Conference for Laparoscopic Liver Resection (LLR), minor LLR was confirmed to be a standard surgical practice, as it has become adopted by an increasing proportion of surgeons. However, it is unclear whether this applies to the more complex group of patients suffering from cirrhosis. Therefore, the aim of this retrospective study was to compare the feasibility and safety of LLR for hepatocellular carcinoma (HCC) between non-liver cirrhosis (NLC) patients and liver cirrhosis (LC) patients at a single high-volume laparoscopy center.

METHODS

From the beginning of 2000 to the end of 2013, open liver resection (OLR) was performed in 99 HCC patients, and LLR was in 118. The HCC patients who underwent LLR were divided into NLC-LLR (n=60) and LC-LLR (n=58) groups, and we compare the short-term outcomes between them.

RESULTS

There was no significant difference in the incidence of blood loss and transfusion requirements between the NLC-LLR group and the LC-LLR group, although wedge resection was mainly performed in the LC-LLR group. There was no significant difference in the complication rate between the two groups, and the remarkable finding was that there was a significantly lower incidence of postoperative ascites in the LC-LLR group than in the NLC-LLR group.

CONCLUSIONS

According to our experience, it appears that LLR for selected HCC patients with cirrhosis is a feasible and promising procedure that is associated with less blood loss and fewer postoperative complications, especially the incidence of postoperative ascites. Further investigations are clearly warranted.

Intermittent Pringle maneuver versus continuous hemihepatic vascular inflow occlusion using extra-glissonian approach in laparoscopic liver resection

BACKGROUND

Despite accumulated experience and advancing techniques for laparoscopic hepatectomy, bleeding remains the major concern during parenchymal transection. The vascular inflow control technique is still important to decrease intraoperative blood loss. The objective of this study was to compare intermittent Pringle with continuous hemihepatic vascular inflow occlusion using extra-glissonian approach in laparoscopic liver resection.

METHODS

Between January 2011 and January 2015, a total of 79 consecutive patients with tumors locating either in the right or in the left hemiliver were included into this retrospective study (45 in the Pringle group vs. 34 in the half-Pringle group). Preoperative clinical characteristics, intraoperative details, postoperative complications and outcomes of patients were compared.

RESULTS

The two groups were well matched according to clinical characteristics, tumor features, types of liver resection and histopathology (P > 0.05). The mean operative time (247.5 ± 61.3 vs. 221.4 ± 48.7 min, P = 0.0446), ischemic duration (62.8 ± 28.3 vs. 44.1 ± 20.5 min, P = 0.0017) and overall declamping time (21.2 ± 8.2 vs. 0.9 ± 1.9 min, P < 0.05) were significantly longer in the Pringle group than in the half-Pringle group. The mean amount of intraoperative blood loss (568.2 ± 325.1 vs. 420.7 ± 307.2 mL, P = 0.0444) and transfusion (266.1 ± 123.4 vs. 203.2 ± 144.6 mL, P = 0.0406) were significantly greater in the Pringle group. The overall operative morbidity rate was significantly higher in the Pringle group (40 vs. 17.6%, P = 0.0324). The Pringle group was associated with significantly higher alanine aminotransferase and aspartate transaminase levels on postoperative day (POD) 7 and lower albumin levels on PODs 1 and 3 (P < 0.05). The C-reactive protein levels were significantly higher in the Pringle group than in the half-Pringle group on POD 1 (37.5 ± 21.4 vs. 28.2 ± 19.0 mg/L, P = 0.0484), POD 3 (114.0 ± 53.4 vs. 90.6 ± 47.9 mg/L, P = 0.0474) and POD 7 (54.9 ± 29.8 vs. 40.1 ± 26.4 mg/L, P = 0.0245).

CONCLUSION

Continuous hemihepatic vascular inflow occlusion using extra-glissonian approach offers the advantages of less operative time and blood loss, less injury and better recovery in laparoscopic liver resection.

Long-term and perioperative outcomes of laparoscopic versus open liver resection for colorectal liver metastases with propensity score matching: a multi-institutional Japanese study

BACKGROUND

The aim of the present study was to clarify the surgical outcome and long-term prognosis of laparoscopic liver resection (LLR) compared with conventional open liver resection (OLR) in patients with colorectal liver metastases (CRLM).

METHODS

A one-to-two propensity score matching (PSM) analysis was applied. Covariates (P < 0.2) used for PSM estimation included preoperative levels of CEA and CA19-9; primary tumor differentiation; primary pathological lymph node metastasis; number, size, location, and distribution of CRLM; existence of extrahepatic metastasis; extent of hepatic resection; total bilirubin and prothrombin activity levels; and preoperative chemotherapy. Perioperative data and long-term survival were compared.

RESULTS

From 2005 to 2010, 1,331 patients with hepatic resection for CRLM were enrolled. By PSM, 171 LLR and 342 OLR patients showed similar preoperative clinical characteristics. Median estimated blood loss (163 g vs 415 g, P < 0.001) and median postoperative hospital stay (12 days vs 14 days; P < 0.001) were significantly reduced in the LLR group. Morbidity and mortality were similar. Five-year rates of recurrence-free, overall, and disease-specific survival did not differ significantly. The R0 resection rate was similar.

CONCLUSIONS

In selected CRLM patients, LLR is strongly associated with lower blood loss and shorter hospital stay and has equivalent long-term survival comparable with OLR.