Evaluation of quality and quantity of randomized controlled trials in hepatobiliary surgery: A scoping/mapping review.

AIM: To evaluate the quantity and quality of randomized controlled trials (RCTs) in hepatobiliary surgery and for identifying gaps in current evidences. METHODS: A systematic search was conducted in MEDLINE (via PubMed), Web of Science, and Cochrane Controlled Register of Trials (CENTRAL) for RCTs of hepatobiliary surgery published from inception until the end of 2023. The quality of each study was assessed using the Cochrane risk-of-bias (RoB) tool. The associations between risk of bias and the region and publication date were also assessed. Evidence mapping was performed to identify research gaps in the field. RESULTS: The study included 1187 records. The number and proportion of published randomized controlled trials (RCTs) in hepatobiliary surgery increased over time, from 13 RCTs (.0005% of publications) in 1970-1979 to 201 RCTs (.003% of publications) in 2020-2023. There was a significant increase in the number of studies with a low risk of bias in RoB domains (p < .01). The proportion of RCTs with low risk of bias improved significantly after the introduction of CONSORT guidelines (p < .001). The evidence mapping revealed a significant research focus on major and minor hepatectomy and cholecystectomy. However, gaps were identified in liver cyst surgery and hepatobiliary vascular surgery. Additionally, there are gaps in the field of perioperative management and nutrition intervention. CONCLUSION: The quantity and quality of RCTs in hepatobiliary surgery have increased over time, but there is still room for improvement. We have identified gaps in current research that can be addressed in future studies.

Comparing a virtual reality head-mounted display to on-screen three-dimensional visualization and two-dimensional computed tomography data for training in decision making in hepatic surgery: a randomized controlled study.

OBJECTIVE: Evaluation of the benefits of a virtual reality (VR) environment with a head-mounted display (HMD) for decision-making in liver surgery. BACKGROUND: Training in liver surgery involves appraising radiologic images and considering the patient's clinical information. Accurate assessment of 2D-tomography images is complex and requires considerable experience, and often the images are divorced from the clinical information. We present a comprehensive and interactive tool for visualizing operation planning data in a VR environment using a head-mounted-display and compare it to 3D visualization and 2D-tomography. METHODS: Ninety medical students were randomized into three groups (1:1:1 ratio). All participants analyzed three liver surgery patient cases with increasing difficulty. The cases were analyzed using 2D-tomography data (group "2D"), a 3D visualization on a 2D display (group "3D") or within a VR environment (group "VR"). The VR environment was displayed using the "Oculus Rift ™" HMD technology. Participants answered 11 questions on anatomy, tumor involvement and surgical decision-making and 18 evaluative questions (Likert scale). RESULTS: Sum of correct answers were significantly higher in the 3D (7.1 ± 1.4, p < 0.001) and VR (7.1 ± 1.4, p < 0.001) groups than the 2D group (5.4 ± 1.4) while there was no difference between 3D and VR (p = 0.987). Times to answer in the 3D (6:44 ± 02:22 min, p < 0.001) and VR (6:24 ± 02:43 min, p < 0.001) groups were significantly faster than the 2D group (09:13 ± 03:10 min) while there was no difference between 3D and VR (p = 0.419). The VR environment was evaluated as most useful for identification of anatomic anomalies, risk and target structures and for the transfer of anatomical and pathological information to the intraoperative situation in the questionnaire. CONCLUSIONS: A VR environment with 3D visualization using a HMD is useful as a surgical training tool to accurately and quickly determine liver anatomy and tumor involvement in surgery.

Comparison of the modified piggyback with standard piggyback and conventional orthotopic liver transplantation techniques: a network meta-analysis.

BACKGROUND: In conventional orthotopic liver transplantation (OLT), the recipient's retrohepatic inferior vena cava (IVC) is completely clamped and replaced with the donor IVC. The piggyback technique has been used to preserve venous return, either via an end-to-side or standard piggyback (SPB), or via a side-to-side or modified piggyback (MPB) anastomosis, using a venous cuff from the recipient hepatic veins with partially clamping and preserves the recipient's inferior vena cava. However, whether these piggyback techniques improve the efficacy of OLT is unclear. To address the low quality of the available evidence, we performed a meta-analysis to compare the efficacy of conventional, MPB, and SPB techniques. METHODS: Literature was searched in Medline and Web of Science databases for relevant articles published until 2021 without any time restriction. A Bayesian network meta-analysis was performed to compare the intra- and postoperative outcomes of conventional OLT, MPB, and SPB techniques. RESULTS: Forty studies were included, comprising 10,238 patients. MPB and SPB had significantly shorter operation times and fewer transfusions of red blood cell and fresh frozen plasma than conventional techniques. However, there were no differences between MPB and SPB in operation time and blood product transfusion. There were also no differences in primary non-function, retransplantation, portal vein thrombosis, acute kidney injury, renal dysfunction, venous outflow complications, length of hospital and intensive care unit stay, 90-day mortality rate, and graft survival between the three techniques. CONCLUSION: MBP and SBP techniques reduce the operation time and need for blood transfusion compared with conventional OLT, but postoperative outcomes are similar. This indicates that all techniques can be implemented based on the experience and policy of the transplant center.

Surgical management of primary liver cancers during the COVID-19 pandemic: overcoming the dilemma with standardization.

BACKGROUND: The present study evaluates the impact of the pandemic on outcomes after surgical treatment for primary liver cancer in a high-volume hepatopancreatobiliary surgery center. METHODS: Patients, who underwent liver resection for primary liver resection between January 2019 and February 2020, comprised pre-pandemic control group. The pandemic period was divided into two timeframes: early pandemic (March 2020-January 2021) and late pandemic (February 2021-December 2021). Liver resections during 2022 were considered as the post-pandemic period. Peri-, and postoperative patient data were gathered from a prospectively maintained database. RESULTS: Two-hundred-eighty-one patients underwent liver resection for primary liver cancer. The number of procedures decreased by 37.1% during early phase of pandemic, but then increased by 66.7% during late phase, which was comparable to post-pandemic phase. Postoperative outcomes were similar between four phases. The duration of hospital stay was longer during the late phase, but not significantly different compared to other groups. CONCLUSION: Despite an initial reduction in number of surgeries, COVID-19 pandemic had no negative effect on outcomes of surgical treatment for primary liver cancer. The structured standard operating protocol in a high-volume and highly specialized surgical center can withstand negative effects, a pandemic may have on treatment of patients.

Repeat liver resection for recurrent intrahepatic cholangiocarcinoma: meta-analysis.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a relatively rare malignancy. The aim of this meta-analysis was to evaluate outcomes of repeat liver resection and non-surgical approaches for treatment of recurrent ICC. METHODS: PubMed, Embase, and Web of Science databases were searched from their inception until March 2021 for studies of patients with recurrent ICC. Studies not published in English were excluded. Two meta-analyses were performed: a single-arm meta-analysis of studies reporting pooled short- and long-term outcomes after repeat liver resection for recurrent ICC (meta-analysis A), and a meta-analysis of studies comparing 1-, 3-, and 5-year overall survival (OS) rates after repeat liver resection and non-surgical approaches for recurrent ICC (meta-analysis B). RESULTS: Of 543 articles retrieved in the search, 28 were eligible for inclusion. Twenty-four studies (390 patients) were included in meta-analysis A and nine studies (591 patients) in meta-analysis B. After repeat liver resection, 1-, 3-, and 5-year OS rates were 87 (95 per cent c.i. 81 to 91), 58 (48 to 68), and 39 (29 to 50) per cent respectively. The 1-, 3-, and 5-year OS rates were higher after repeat liver resection than without surgery: odds ratio 2.70 (95 per cent c.i. 1.28 to 5.68), 2.89 (1.15 to 7.27), and 5.91 (1.59, 21.90) respectively. CONCLUSION: Repeat liver resection is a suitable strategy for recurrent ICC in selected patients. It improves short- and long-term outcomes compared with non-surgical treatments.

Portal vein arterialization as a salvage procedure in hepatopancreatobiliary surgery: a systematic review.

Background: Portal vein arterialization (PVA) is a possible option when hepatic artery reconstruction is impossible during liver resection. The aim of this study was to review the literature on the clinical application of PVA in hepatopancreatobiliary (HPB) surgery. Methods: We performed a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched the PubMed, Embase and Web of Science databases until December 2019. Experimental (animal) studies, review articles and letters were excluded. Results: Twenty studies involving 57 patients were included. Cholangiocarcinoma was the most common indication for surgery (40 patients [74%]). An end-to-side anastomosis between a celiac trunk branch and the portal vein was the main PVA technique (35 patients [59%]). Portal hypertension was the most common longterm complication (12 patients [21%] after a mean of 4.1 mo). The median followup period was 12 (range 1-87) months. The 1-, 3- and 5-year survival rates were 64%, 27% and 20%, respectively. Conclusion: Portal vein arterialization can be considered as a rescue option to improve the outcome in patients with acute liver de-arterialization when arterial reconstruction is not possible. To prevent portal hypertension and liver injuries due to thrombosis or overarterialization, vessel calibre adjustment and timely closure of the anastomosis should be considered. Further prospective experimental and clinical studies are needed to investigate the potential of this procedure in patients whose liver is suddenly de-arterialized during HPB procedures.

Contexte: L'artérialisation de la veine porte (AVP) est une option envisageable lorsqu'il est impossible de reconstruire l'artère hépatique au moment d'une résection du foie. Le but de cette étude était de faire le point sur la littérature concernant l'application clinique de l'AVP en cours de chirurgie hépatopancréatobiliaire (HPB). Méthodes: Nous avons procédé à une revue systématique selon les directives PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Nous avons interrogé systématiquement les bases de données PubMed, Embase et Web of Science jusqu'à décembre 2019. Les études expérimentales (chez l'animal), les articles de synthèse et les lettres ont été exclus. Résultats: Vingt études regroupant 57 patients ont été incluses. Le cholangiocarcinome était la plus fréquente indication de la chirurgie (40 patients [74 %]). L'anastomose terminolatérale d'une branche du tronc cæliaque avec la veine porte a été la principale technique d'AVP (35 patients [59 %]). L'hypertension portale a été la plus fréquente complication (12 patients [21 %] après une moyenne de 4,1 mois). Le suivi médian a été de 12 mois (éventail, 1­87 mois). Les taux de survie moyens à 1, 3 et 5 ans ont été de 64 %, 27 % et 20 %, respectivement. Conclusion: L'artérialisation de la veine porte peut être considérée comme une option de dernier ressort pour améliorer l'état des patients victimes d'une désartérialisation hépatique aiguë lorsque la reconstruction artérielle est impossible. Pour prévenir l'hypertension portale et les lésions au foie dues à la thrombose ou à l'hyperartérialisation, il faut veiller à ajuster le calibre vasculaire et fermer rapidement l'anastomose. D'autres études expérimentales et cliniques prospectives s'imposent afin d'analyser le potentiel de cette intervention chez les patients dont le foie se trouve subitement désartérialisé durant une chirurgie HPB.

A systematic review and meta-analysis of randomized controlled trials comparing laparoscopic and open liver resection.

BACKGROUND/PURPOSE: The dissemination of laparoscopic liver resection (LLR) has been based on non-randomized studies and reviews of these. Aim of this study was to evaluate if the randomized evidence comparing LLR to open liver resection (OLR) supports these findings. METHODS: A prospectively registered (reviewregistry866) systematic review and meta-analysis following Cochrane and PRISMA guidelines comparing LLR to OLR for benign and malignant diseases was performed via Medline, Web of Science, CENTRAL up to 31.12.2020. The main outcome was postoperative complications. Risk of bias was assessed with the Cochrane Risk of Bias tool 2.0, certainty of evidence was assessed using the GRADE approach. RESULTS: The search yielded 2080 results. 13 RCTs assessing mostly minor liver resections with 1457 patients were included. There were reduced odds of experiencing any complication (Odds ratio (OR) [95% confidence interval (CI)]: 0·42 [0·30, 0·58]) and severe complications (OR[CI]: 0·51 [0·31, 0·84]) for patients undergoing LLR. LOS was shorter (Mean difference (MD) [CI]: -2·90 [-3·88, -1·92] days), blood loss was lower (MD: [CI]: -115·41 [-146·08, -84·75] ml), and functional recovery was better for LLR. All other outcomes showed no significant differences. CONCLUSIONS: LLR shows significant postoperative benefits. RCTs assessing long-term outcomes and major resections are needed.

Impact of Surgeon's Experience on Vascular and Haemorrhagic Complications After Kidney Transplantation.

OBJECTIVE: The aim of this study was to investigate the independent risk factors of vascular and haemorrhagic complications after kidney transplantation (KTx) and to evaluate how the surgeon's experience affects the rate of vascular and haemorrhagic complications. METHODS: After exclusion of paediatric and multi-organ transplantations, 1462 KTx operations between 2000 and 2016 were analysed. Independent risk factors were evaluated by multivariable logistic regression analysis. The generalised estimating equation logit model was used to display learning curve progression and determine the best cut off number of KTx operations to reduce vascular and haemorrhagic complications. RESULTS: Vascular and haemorrhagic complications occurred in 38 KTx cases (2.6%). Renal vein thrombosis was the most common complication (0.6%). Graft loss occurred in 11 of 38 (28.9%) cases. Donor age of >60 years (OR 3.687, 95% CI 1.663-8.175, p = 0.001), recipient cardiovascular disease (CVD) (OR 2.270, 95% CI 1.071-4.810, p = 0.032), and surgeon's experience (OR 0.875, 95% CI 0.783-0.977, p = 0.018) were independent predictors of vascular and haemorrhagic complications. Twenty-six previous KTx operations are needed to decrease predicted probability of post-KTx vascular and haemorrhagic complications below 2.6%. CONCLUSIONS: The surgeon's experience is an independent risk factor for vascular and haemorrhagic complications after KTx. Acceptable post-operative vascular and haemorrhagic complications are achieved after a minimum of 26 KTx. As a donor age of >60 years and recipient CVD are also independent risk factors for vascular and haemorrhagic complications, it is suggested that these patients should preferably be operated on by surgeons who have performed more than 26 KTx operations.

The optimal intestinal segment length for experimental size-mismatched intestinal transplantation: Defining the maximum length with the lowest blood flow needs in a porcine model.

Transplanted Intestinal Segments (IS) must match the perfusion capacities of the recipient. This can be challenging during a size-mismatched SBTX. In this study, we defined the maximum IS length with lowest blood flow needs in a porcine model by evaluating the physiological perfusion rates of different IS lengths. Blood flow in the SMA, aorta segment four, and general circulatory parameters were monitored before and after sequential intestinal resection. IS lengths of 30 cm, 60 cm, 120 cm, and 300 cm (n = 8 each) were compared. The IS blood flow requirements increased with IS length (30 cm: 19.5 ± 3.4 mL/min; 60 cm: 16.9 ± 6.7 mL/min; 120 cm: 34.9 ± 8.5 mL/min; 300 cm: 62.9 ± 11.6 mL/min). Absolute IS blood flow (P = .004), percentage IS blood flow uptake from the SMA (P = .001), and percentage IS blood flow uptake from the aorta (P = .005) increased significantly between 60 cm and 120 cm. We concluded that 60 cm was the maximum IS length before blood flow demands significantly increased in a porcine model.

Does acid-base equilibrium correlate with remnant liver volume during stepwise liver resection?

Small for size and flow syndrome (SFSF) is one of the most challenging complications following extended hepatectomy (EH). After EH, hepatic artery flow decreases and portal vein flow increases per 100 g of remnant liver volume (RLV). This causes hypoxia followed by metabolic acidosis. A correlation between acidosis and posthepatectomy liver failure has been postulated but not studied systematically in a large animal model or clinical setting. In our study, we performed stepwise liver resections on nine pigs to defined SFSF limits as follows: step 1: segment II/III resection, step 2: segment IV resection, step 3: segment V/VIII resection (RLV: 75, 50, and 25%, respectively). Blood gas values were measured before and after each step using four catheters inserted into the carotid artery, internal jugular vein, hepatic artery, and portal vein. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. EH correlated with reduced BE in the hepatic artery. Pco2 values increased after 75% resection in the jugular vein. In contrast, arterial Po2 increased after every resection, whereas the venous Po2 decreased slightly. There were differences in venous [Formula: see text], BE in the hepatic artery, and Pco2 in the jugular vein after 75% liver resection. Because 75% resection is the limit for SFSF, these noninvasive blood evaluations may be used to predict SFSF. Further studies with long-term follow-up are required to validate this correlation.NEW & NOTEWORTHY This is the first study to evaluate acid-base parameters in major central and hepatic vessels during stepwise liver resection. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. Extended hepatectomy correlated with reduced BE in the hepatic artery. Because 75% resection is the limit for small for size and flow syndrome (SFSF), postresection blood gas evaluations may be used to predict SFSF.

Prophylaxis of lymphocele formation after kidney transplantation via peritoneal fenestration: a systematic review.

Lymphocele formation after kidney transplantation is a frequent complication which causes pain, secondary graft loss, rehospitalizations and reoperations. Therefore, prophylaxis of lymphocele formation is of utmost importance. To assess the effectiveness of peritoneal fenestration in renal transplantation to prevent lymphocele development. A systematic literature search was conducted combined with hand-searches on lymphocele prevention following renal transplantation using peritoneal fenestration. A qualitative and quantitative analysis of included trials was conducted. We identified three trials including 414 patients and 437 transplantations which studied peritoneal fenestration. Only one randomized controlled trial was identified. Critical appraisal uncovered a number of methodological flaws, predominantly in the nonrandomized studies. Most importantly endpoint definitions varied among trials, selection bias was high and interventions and follow-up were not standardized. Meta-analysis of the included trials showed a significant reduction of clinically symptomatic lymphoceles (OR: 0.23, 95% CI: 0.09-0.64, P = 0.005) and overall postoperative fluid collections (OR: 0.49, 95% CI: 0.28-0.88, P = 0.02) without a significant increase in other surgical complications. Although peritoneal fenestration is a promising technique to reduce lymphocele formation, only few studies have investigated this technique so far. Given the low methodological quality of included trials, more studies are necessary to evaluate the effectiveness and the risks and benefits of this technique.

A simplified technique of pancreas transplantation in a porcine model.

BACKGROUND: The incidence of diabetes has been steadily increasing. The only curative option for diabetes is pancreas transplantation (PTx). Porcine models are valuable because of their anatomical and physiological similarities to human beings. Our aim is to introduce a simplified technique of PTx in a porcine model. METHODS: In Landrace pigs (n = 32), after median laparotomy, the pancreas was mobilized, and the portal and splenic veins were divided. The proper hepatic and splenic arteries and the bile duct were also prepared, and the duodenal bulb was prepared and stapled. The third portion of the duodenum was freed up to the ligament of Treitz and stapled, and the renal arteries were ligated. After systemic heparinization, the pancreas was perfused through the abdominal aorta with histidine-tryptophan-ketoglutarate solution. The portal and splenic veins were cut for evaluating the sufficiency of perfusion. Whole pancreaticoduodenal graft was procured along with an aortic jump graft containing mesenteric and celiac trunks. In recipients, after total pancreatectomy, the suprarenal inferior vena cava and infrarenal aorta were prepared for vascular anastomosis in an end-to-side manner. After pancreas reperfusion, duodenoduodenostomy was performed in an end-to-side manner. RESULTS: Median cold and warm ischemia times were 10 h (range, 9-14 h) and 50 min (range, 35-80 min), respectively. The hemodynamic status was stable throughout the operation. The median follow-up period was 7 days (range, 4-10). There were no major intra- and postoperative complications. CONCLUSION: By using an aortic jump graft, there was no need to perform additional arterial reconstruction resulting in a short warm ischemic and operation time. End-to-side portocaval and duodenoduodenal anastomoses make this model of PTx a very feasible method for experimental evaluations.

Promising Results of Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy for Perihilar Cholangiocarcinoma in a Systematic Review and Single-Arm Meta-Analysis.

BACKGROUND: ALPPS popularity is increasing among surgeons worldwide and its indications are expanding to cure patients with primarily unresectable liver tumors. Few reports recommended limitations or even contraindications of ALPPS in perihilar cholangiocarcinoma (phCC). Here, we discuss the results of ALPPS in patients with phCC in a systematic review as well as a pooled data analysis. METHODS: MEDLINE and Web of Science databases were systematically searched for relevant literature up to December 2023. All studies reporting ALPPS in the management of phCC were included. A single-arm meta-analysis of proportions was carried out to estimate the overall rate of outcomes. RESULTS: After obtaining 207 articles from the primary search, data of 18 studies containing 112 phCC patients were included in our systematic review. Rates of major morbidity and mortality were calculated to be 43% and 22%, respectively. The meta-analysis revealed a PHLF rate of 23%. One-year disease-free survival was 65% and one-year overall survival was 69%. CONCLUSIONS: ALPPS provides a good chance of cure for patients with phCC in comparison to alternative treatment options, but at the expense of debatable morbidity and mortality. With refinement of the surgical technique and better perioperative patient management, the results of ALPPS in patients with phCC were improved.

Clinical Research in Renal Transplantation: A Bibliometric Perspective on a Half-century of Innovation and Progress.

BACKGROUND: Groundbreaking biomedical research has transformed renal transplantation (RT) into a widespread clinical procedure that represents the mainstay of treatment for end-stage kidney failure today. Here, we aimed to provide a comprehensive bibliometric perspective on the last half-century of innovation in clinical RT. METHODS: The Web of Science Core Collection was used for a comprehensive screening yielding 123 303 research items during a 50-y period (January 1973-October 2022). The final data set of the 200 most-cited articles was selected on the basis of a citation-based strategy aiming to minimize bias. RESULTS: Studies on clinical and immunological outcomes (n = 63 and 48), registry-based epi research (n = 38), and randomized controlled trials (n = 35) dominated the data set. Lead US authors have signed 110 of 200 articles. The overall level of evidence was high, with 84% of level1 and -2 reports. Highest numbers of these articles were published in New England Journal of Medicine , Transplantation , and American Journal of Transplantation. Increasing trend was observed in the number of female authors in the postmillennial era (26% versus 7%). CONCLUSIONS: This study highlights important trends in RT research of the past half-century. This bibliometric perspective identifies the most intensively researched areas and shift of research interests over time; however, it also describes important imbalances in distribution of academic prolificacy based on topic, geographical aspects, and gender.

Do we need animal hands-on courses for transplantation surgery?

BACKGROUND: Transplantation surgery requires many years of training. This study evaluates and presents the results of our recent four-yr animal hands-on courses of transplantation surgery on participants' training. METHODS: Since 2008, five two-d hands-on courses of transplantation surgery were performed on swine models at our department. Sixty-one participants were asked to answer three questionnaires (pre-course, immediate post-course, subsequent post-course). The questions pertained to their past education, expectations, and evaluation of our courses, as well as our course's effectiveness in advancing their surgical abilities. The results were analyzed, compared and are presented herein. RESULTS: On average, 1.8 multiorgan procurements, 2.3 kidney, 1.5 liver, and 0.7 pancreas transplantations were performed by each participant. 41.7% of participants considered their previous practical training only satisfactory; 85% hoped for more opportunities to practice surgery; 73.3% evaluated our courses as very good; and 95.8% believed that our courses had fulfilled their expectations. 66% found the effectiveness of our course in advancing their surgical abilities very good; 30% good, and 4% satisfactory. CONCLUSION: Animal hands-on courses of transplantation surgery are one of the best options to learn and practice different operations and techniques in a near to clinical simulated model. Regular participation in such courses with a focus on practical issues can provide optimal opportunities for trainees with the advantage of direct mentoring and feedback.

Intestinal transplantation: review of operative techniques.

The improvement of outcomes in intestinal transplantation (ITx) over the last two decades has been made possible through standardization in surgical techniques, improvements in immunosuppressive and induction protocols, and post-operative patient care. From a surgical technical point of view, all different types of small bowel containing transplants can be categorized into three main prototypes, including isolated small bowel, liver-small bowel, and multivisceral transplantations. In this review, we describe these three main prototypes and discuss the most important technical modifications of each type, as well as donor and recipient procedures, and highlight the more recent operative technical topics of discussion in the literature.