Extent of resection and underlying liver disease influence the accuracy of the preoperative risk assessment with the ACS NSQIP Risk Calculator.

BACKGROUND: Depending on the extent of liver resection and the underlying liver disease, liver surgery is associated with a significant risk for postoperative complications. Therefore, adequate patient selection is crucial. The aim of this study was to assess the accuracy of the American College of Surgeons risk calculator (ACS-RC) taking into account liver parenchyma quality and type of liver resection. STUDY DESIGN: From 01/2019 to 03/2023 patients undergoing open or minimally invasive liver resection for benign or malignant indications at the University Hospital Basel were included. Brier score and feature importance analysis (FIA) were performed to investigate the accuracy of the ACS-RC. RESULTS: 376 patients were included, 214 (57%) underwent partial hepatectomy, 89 (24%) hemi-hepatectomy and 73 (19%) trisegmentectomy. Most patients had underlying liver diseases, 143 (38%) patients with fibrosis, 75 (20%) with steatosis and 61 (16%) with cirrhosis. The ACS-RC adequately predicted surgical site infection (Brier score 0.035), urinary tract infection (Brier score 0.038) and death (Brier score 0.046), moderate accuracy was achieved for serious complications (Brier score 0.216) and overall complications (Brier score 0.180). Compared to the overall cohort, the prediction was limited in patients with cirrhosis, fibrosis and steatosis as well as for patients undergoing hemi-hepatectomies and trisegmentectomies. Including liver parenchyma quality led to improved prediction accuracy. CONCLUSION: The ACS-RC is a reliable tool to estimate 30-day postoperative morbidity, especially for patients with healthy liver parenchyma undergoing partial liver resections. However, accurate perioperative risk prediction should adjust for underlying liver disease and extended liver resections.

Informing Decision-making for Transected Margin Reresection in Intraductal Papillary Mucinous Neoplasm-derived PDAC: An International Multicenter Study.

OBJECTIVE: To assess the prognostic impact of margin status in patients with resected intraductal papillary mucinous neoplasms (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and to inform future intraoperative decision-making on handling differing degrees of dysplasia on frozen section. SUMMARY BACKGROUND DATA: The ideal oncologic surgical outcome is a negative transection margin with normal pancreatic epithelium left behind. However, the prognostic significance of reresecting certain degrees of dysplasia or invasive cancer at the pancreatic neck margin during pancreatectomy for IPMN-derived PDAC is debatable. METHODS: Consecutive patients with resected and histologically confirmed IPMN-derived PDAC (2002-2022) from six international high-volume centers were included. The prognostic relevance of a positive resection margin (R1) and degrees of dysplasia at the pancreatic neck margin were assessed by log-rank test and multivariable Cox-regression for overall survival (OS) and recurrence-free survival (RFS). RESULTS: Overall, 832 patients with IPMN-derived PDAC were included with 322 patients (39%) having an R1-resection on final pathology. Median OS (mOS) was significantly longer in patients with an R0 status compared to those with an R1 status (65.8 vs. 26.3 mo P<0.001). Patients without dysplasia at the pancreatic neck margin had similar OS compared to those with low-grade dysplasia (mOS: 78.8 vs. 66.8 months, P=0.344). However, high-grade dysplasia (mOS: 26.1 mo, P=0.001) and invasive cancer (mOS: 25.0 mo, P<0.001) were associated with significantly worse OS compared to no or low-grade dysplasia. Patients who underwent conversion of high-risk margins (high-grade or invasive cancer) to a low-risk margin (low-grade or no dysplasia) after intraoperative frozen section had significantly superior OS compared to those with a high-risk neck margin on final pathology (mOS: 76.9 vs. 26.1 mo P<0.001). CONCLUSIONS: In IPMN-derived PDAC, normal epithelium or low-grade dysplasia at the neck have similar outcomes while pancreatic neck margins with high-grade dysplasia or invasive cancer are associated with poorer outcomes. Conversion of a high-risk to low-risk margin after intraoperative frozen section is associated with survival benefit and should be performed when feasible.

Total versus Partial Pancreatectomy in Patients with Pancreatic Cancer Arising from Multifocal or Diffuse Intraductal Papillary Mucinous Neoplasia - A Multicenter Observational Study.

AIM: To investigate the impact of total pancreatectomy (TP) on oncological outcomes for patients at high-risk of local recurrence or secondary progression in the remnant gland after partial pancreatectomy (PP) for IPMN-associated cancer. SUMMARY BACKGROUND DATA: Major risk factors for invasive progression in the remnant gland include multifocality, diffuse main duct dilation, and the presence of invasive cancer. In these high-risk patients, a TP may be oncologically beneficial. However, current guidelines discourage TP, especially in elderly patients. METHODS: This international multicenter study compares TP versus PP in patients with adenocarcinoma arising from multifocal or diffuse IPMN (2002-2022). Log-rank test and multivariable Cox-analysis with interaction analysis was performed to assess overall survival (OS), disease-free survival (DFS), and local-DFS. RESULTS: Of 359 included patients, 162 (45%) were treated with TP, whereas 197 (55%) underwent PP. Despite TP and PP having similar R0-rates (59% vs. 58%, P=0.866), patients undergoing a TP had significantly longer local-DFS compared to PP (P=0.039). However, no difference in OS was observed between the two surgical approaches (P=0.487). In a multivariable analysis, young age (optimal cut-off ≤63.6 yrs) was associated with an OS benefit derived from TP (HR:0.44, 95%CI:0.22-0.89), whereas no significant difference was observed in elderly patients (HR:1.24, 95%CI:0.92-1.67, Pinteraction=0.007). CONCLUSION: Since overall, patients with diffuse or multifocal IPMN with an invasive component do not benefit from TP in terms of OS, the indication for TP may be individualized to young patients who have sufficient life expectancy to benefit from the prevention of secondary progression or local recurrence.

The PLET (Portable Laparoscopic Endo-Trainer) study: a randomized controlled trial of home- versus hospital-based surgical training.

PURPOSE: The purpose of this study was to assess the effect of training with a personal, portable laparoscopic endo-trainer (PLET) on residents' laparoscopic skills. METHODS: The study took place at a tertiary-care academic university hospital in Switzerland. All participants were randomized to either a home- or hospital-based PLET training group, and surgical skill performance was assessed using five laparoscopic exercises. 24 surgical residents, 13 females and 11 males, were enrolled at any training stage. Nine residents completed the assessments. Endpoints consisted of subjective and objective assessment ratings as well as exercise time and qualitative data up to 12 weeks. The primary outcome was the difference in exercise time and secondary outcomes included performance scores as well as qualitative data. RESULTS: The hospital-based training group performed exercises number 1, 3 and 4 faster at 12 weeks than at baseline (p = .003, < 0.001 and 0.024). Surgical skill performance was not statistically significantly different in any of the endpoints between the hospital- and home-based training groups at 12 weeks. Both the subjective and objective assessment ratings significantly improved in the hospital-based training group between baseline and 12 weeks (p = .006 and 0.003, respectively). There was no statistically significant improvement in exercise time as well as subjective and objective assessment ratings over time in the home-based training group. The qualitative data suggested that participants who were randomized to the hospital-based training group wished to have the PLET at home and vice versa. Several participants across groups lacked motivation because of their workload or time constraints, though most believed the COVID-19 pandemic had no influence on their motivation or the time they had for training. CONCLUSION: The PLET enhances laparoscopic surgical skills over time in a hospital-based training setting. In order to understand and optimize motivational factors, further research is needed. TRIAL REGISTRATION: This trial was retrospectively registered on clinicaltrials.gov (NCT06301230).

Preoperative Surgical or Endoscopic Bile Duct Drainage in Pancreatic Cancer.

BACKGROUND: Patients with pancreatic cancer and obstructive jaundice routinely undergo endoscopic stent placement (ES). It is well known that ES causes bacterial contamination and infectious complications after pancreatic resection. OBJECTIVE: To compare short-term outcomes and survival in patients undergoing pancreatic head resection after preoperative ES vs preoperative surgical drainage (SD) via T-tube insertion. METHODS: Patients with obstructive jaundice who underwent SD or ES from 2016 to 2022 were identified from a prospective database. Outcome analyses included microbiological bile contamination, overall morbidity and assessment of the overall complication burden using the Comprehensive Complication Index (CCI). Overall survival was investigated by Kaplan‒Meier analysis. RESULTS: A total of 55 patients with SD were identified and matched with 110 ES patients. After the primary intervention, ES patients experienced more complications (ES: 17.3% vs. SD: 3.6%; P=0.013). The overall complication burden after pancreatic resection was higher in ES patients than in SD patients (CCI: 27.2 vs. 19.9; P=0.022). Additionally, bacterial contamination of the bile was more frequent in ES patients compared to SD individuals (94.3% vs. 7.1%; P<0.001) with similar bacteria in 83.3% of postoperative abdominal infections in ES patients. While overall survival did not differ between the two groups, patients with postinterventional complications after ES had an impaired survival compared to those without complications (11.3 mo vs. 20.4 mo; P=0.03). CONCLUSION: SD for obstructive jaundice in resectable pancreatic cancer is associated with a lower overall complication burden. Additionally, patients with complications after ES experience worse overall survival. These findings indicate to rethink our standards of treatment of obstructive jaundice in patients with pancreatic cancer.

Challenges in multi-centric generalization: phase and step recognition in Roux-en-Y gastric bypass surgery.

PURPOSE: Most studies on surgical activity recognition utilizing artificial intelligence (AI) have focused mainly on recognizing one type of activity from small and mono-centric surgical video datasets. It remains speculative whether those models would generalize to other centers. METHODS: In this work, we introduce a large multi-centric multi-activity dataset consisting of 140 surgical videos (MultiBypass140) of laparoscopic Roux-en-Y gastric bypass (LRYGB) surgeries performed at two medical centers, i.e., the University Hospital of Strasbourg, France (StrasBypass70) and Inselspital, Bern University Hospital, Switzerland (BernBypass70). The dataset has been fully annotated with phases and steps by two board-certified surgeons. Furthermore, we assess the generalizability and benchmark different deep learning models for the task of phase and step recognition in 7 experimental studies: (1) Training and evaluation on BernBypass70; (2) Training and evaluation on StrasBypass70; (3) Training and evaluation on the joint MultiBypass140 dataset; (4) Training on BernBypass70, evaluation on StrasBypass70; (5) Training on StrasBypass70, evaluation on BernBypass70; Training on MultiBypass140, (6) evaluation on BernBypass70 and (7) evaluation on StrasBypass70. RESULTS: The model's performance is markedly influenced by the training data. The worst results were obtained in experiments (4) and (5) confirming the limited generalization capabilities of models trained on mono-centric data. The use of multi-centric training data, experiments (6) and (7), improves the generalization capabilities of the models, bringing them beyond the level of independent mono-centric training and validation (experiments (1) and (2)). CONCLUSION: MultiBypass140 shows considerable variation in surgical technique and workflow of LRYGB procedures between centers. Therefore, generalization experiments demonstrate a remarkable difference in model performance. These results highlight the importance of multi-centric datasets for AI model generalization to account for variance in surgical technique and workflows. The dataset and code are publicly available at https://github.com/CAMMA-public/MultiBypass140.

Is neoadjuvant chemotherapy followed by surgery the appropriate treatment for esophagogastric signet ring cell carcinomas? A systematic review and meta-analysis.

Background: The impact of neoadjuvant chemotherapy (nCTX) on survival and tumor response in patients with esophagogastric signet ring cell carcinoma (SRCC) is still controversial. Methods: Two independent reviewers performed a systematic literature search in Medline, CENTRAL, and Web of Science including prospective and retrospective two-arm non-randomized and randomized controlled studies (RCTs). Data was extracted on overall survival (OS) and tumor regression in resected esophagogastric SRCC patients with or without nCTX. Survival data was analyzed using published hazard ratios (HR) if available or determined it from other survival data or survival curves. OS and histopathological response rates by type of tumor (SRCC vs. non-SRCC) were also investigated. Results: Out of 559 studies, ten (1 RCT, 9 non-RCTs) were included in this meta-analysis (PROSPERO CRD42022298743) investigating 3,653 patients in total. The four studies investigating survival in SRCC patients treated with nCTX + surgery vs. surgery alone showed no survival benefit for neither intervention, but heterogeneity was considerable (HR, 1.01; 95% CI, 0.61-1.67; p = 0.98; I2 = 89%). In patients treated by nCTX + surgery SRCC patients showed worse survival (HR, 1.45; 95% CI, 1.21-1.74; p < 0.01) and lower rate of major histopathological response than non-SRCC patients (OR, 2.47; 95% CI, 1.78-3.44; p < 0.01). Conclusion: The current meta-analysis could not demonstrate beneficial effects of nCTX for SRCC patients. Histopathological response to and survival benefits of non-taxane-based nCTX seem to be lower in comparison to non-SRC esophagogastric cancer. However, certainty of evidence is low due to the scarcity of high-quality trials. Further research is necessary to determine optimal treatment for SRCC patients. Systematic Review Registration: https://www.crd.york.ac.uk/, PROSPERO (CRD42022298743).

Breaking down barriers to bariatric care: a qualitative study on how telemedicine could transform patient experiences in a Swiss monocentric setting.

OBJECTIVE: Telemedicine is becoming an increasingly feasible option for patients with chronic diseases due to its convenience, cost-effectiveness and ease of access. While there are certain limitations, the benefits can be appreciated by those seeking repetitive care. The perception of telemedicine as an alternative to recurrent, in-person appointments for patients with obesity in structured bariatric programmes is still unclear. This content analysis' primary endpoint was to explore how patients within our bariatric programme perceived telemedicine and virtual consultations as a new way of communication during COVID-19. DESIGN: A qualitative study using semistructured interviews and qualitative content analysis method by Elo and Kyngäs following four steps: data familiarisation, coding and categorising with Quirkos software and final interpretation guided by developed categories. SETTING: University Hospital, Switzerland. PARTICIPANTS: We conducted 33 interviews with 19 patients from a structured bariatric programme. RESULTS: Most patients shared positive experiences, acknowledging the convenience and accessibility of virtual appointments. Others voiced concerns, especially regarding telemedicine's limitations. These reservations centred around the lack of physical examinations, difficulties in fostering connections with healthcare providers, as well as barriers stemming from language and technology. The research identified a spectrum of patient preferences in relation to telemedicine versus in-person visits, shaped by the immediacy of their concerns and their availability. CONCLUSION: While telemedicine is increasingly accepted by the public and provides accessible and cost-effective options for routine follow-up appointments, there are still obstacles to overcome, such as a lack of physical examination and technological limitations. However, integrating virtual alternatives, like phone or video consultations, into routine bariatric follow-ups could improve continuity and revolutionise bariatric care.

Machine learning-based preoperative analytics for the prediction of anastomotic leakage in colorectal surgery: a swiss pilot study.

BACKGROUND: Anastomotic leakage (AL), a severe complication following colorectal surgery, arises from defects at the anastomosis site. This study evaluates the feasibility of predicting AL using machine learning (ML) algorithms based on preoperative data. METHODS: We retrospectively analyzed data including 21 predictors from patients undergoing colorectal surgery with bowel anastomosis at four Swiss hospitals. Several ML algorithms were applied for binary classification into AL or non-AL groups, utilizing a five-fold cross-validation strategy with a 90% training and 10% validation split. Additionally, a holdout test set from an external hospital was employed to assess the models' robustness in external validation. RESULTS: Among 1244 patients, 112 (9.0%) suffered from AL. The Random Forest model showed an AUC-ROC of 0.78 (SD: ± 0.01) on the internal test set, which significantly decreased to 0.60 (SD: ± 0.05) on the external holdout test set comprising 198 patients, including 7 (3.5%) with AL. Conversely, the Logistic Regression model demonstrated more consistent AUC-ROC values of 0.69 (SD: ± 0.01) on the internal set and 0.61 (SD: ± 0.05) on the external set. Accuracy measures for Random Forest were 0.82 (SD: ± 0.04) internally and 0.87 (SD: ± 0.08) externally, while Logistic Regression achieved accuracies of 0.81 (SD: ± 0.10) and 0.88 (SD: ± 0.15). F1 Scores for Random Forest moved from 0.58 (SD: ± 0.03) internally to 0.51 (SD: ± 0.03) externally, with Logistic Regression maintaining more stable scores of 0.53 (SD: ± 0.04) and 0.51 (SD: ± 0.02). CONCLUSION: In this pilot study, we evaluated ML-based prediction models for AL post-colorectal surgery and identified ten patient-related risk factors associated with AL. Highlighting the need for multicenter data, external validation, and larger sample sizes, our findings emphasize the potential of ML in enhancing surgical outcomes and inform future development of a web-based application for broader clinical use.

Long-term quality of life after hybrid robot-assisted and open Ivor Lewis esophagectomy for esophageal cancer in a single center: a comparative analysis.

PURPOSE: Due to improved survival of esophageal cancer patients, long-term quality of life (QoL) is increasingly gaining importance. The aim of this study is to compare QoL outcomes between open Ivor Lewis esophagectomy (Open-E) and a hybrid approach including laparotomy and a robot-assisted thoracic phase (hRob-E). Additionally, a standard group of healthy individuals serves as reference. METHODS: With a median follow-up of 36 months after hRob-E (n = 28) and 40 months after Open-E (n = 43), patients' QoL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) QoL Questionnaire Core 30 (QLQ-C30) and the EORTC Esophagus specific QoL questionnaire 18 (QLQ-OES18). RESULTS: Patients showed similar clinical-pathological characteristics, but hRob-E patients had significantly higher ASA scores at surgery (p < 0.001). Patients and healthy controls reported similar global health status and emotional and cognitive functions. However, physical functioning of Open-E patients was significantly reduced compared to healthy controls (p = 0.019). Operated patients reported reduced role and social functioning, fatigue, nausea and vomiting, dyspnea, and diarrhea. A trend towards a better pain score after hRob-E compared to Open-E emerged (p = 0.063). Regarding QLQ-OES18, hRob-E- and Open-E-treated patients similarly reported eating problems, reflux, and troubles swallowing saliva. CONCLUSIONS: The global health status is not impaired after esophagectomy. Despite higher ASA scores, QoL of hRob-E patients is similar to that of patients operated with Open-E. Moreover, patients after hRob-E appear to have a better score regarding physical functioning and a better pain profile than patients after Open-E, indicating a benefit of minimally invasive surgery.

Structured feedback and operative video debriefing with critical view of safety annotation in training of laparoscopic cholecystectomy: a randomized controlled study.

BACKGROUND: The learning curve in minimally invasive surgery (MIS) is lengthened compared to open surgery. It has been reported that structured feedback and training in teams of two trainees improves MIS training and MIS performance. Annotation of surgical images and videos may prove beneficial for surgical training. This study investigated whether structured feedback and video debriefing, including annotation of critical view of safety (CVS), have beneficial learning effects in a predefined, multi-modal MIS training curriculum in teams of two trainees. METHODS: This randomized-controlled single-center study included medical students without MIS experience (n = 80). The participants first completed a standardized and structured multi-modal MIS training curriculum. They were then randomly divided into two groups (n = 40 each), and four laparoscopic cholecystectomies (LCs) were performed on ex-vivo porcine livers each. Students in the intervention group received structured feedback after each LC, consisting of LC performance evaluations through tutor-trainee joint video debriefing and CVS video annotation. Performance was evaluated using global and LC-specific Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores. RESULTS: The participants in the intervention group had higher global and LC-specific OSATS as well as global and LC-specific GOALS scores than the participants in the control group (25.5 ± 7.3 vs. 23.4 ± 5.1, p = 0.003; 47.6 ± 12.9 vs. 36 ± 12.8, p < 0.001; 17.5 ± 4.4 vs. 16 ± 3.8, p < 0.001; 6.6 ± 2.3 vs. 5.9 ± 2.1, p = 0.005). The intervention group achieved CVS more often than the control group (1. LC: 20 vs. 10 participants, p = 0.037, 2. LC: 24 vs. 8, p = 0.001, 3. LC: 31 vs. 8, p < 0.001, 4. LC: 31 vs. 10, p < 0.001). CONCLUSIONS: Structured feedback and video debriefing with CVS annotation improves CVS achievement and ex-vivo porcine LC training performance based on OSATS and GOALS scores.

Laparoscopic but not open surgical skills can be transferred to robot-assisted surgery: A systematic review and meta-analysis.

BACKGROUND: With an increase in robot-assisted surgery across all specialties, adequate training and credentialing strategies need to be identified to ensure patients safety. The meta-analysis assesses the transferability of technical surgical skills between laparoscopic surgery, open surgery, and robot-assisted surgery. DESIGN: A systematic search was conducted in Medline, Cochrane Central Register of Controlled Trials, and Web of Science. Outcomes were categorized into time, process, product, and composite outcome measures and pooled separately using Hedges'g (standardized mean difference [SMD]). Subgroup analyses were performed to assess the effect of study design, virtual reality platforms and task difficulty. RESULTS: Out of 14,120 screened studies, 30 were included in the qualitative synthesis and 26 in the quantitative synthesis. Technical surgical skill transfer was demonstrated from laparoscopic to robot-assisted surgery (composite: SMD 0.40, 95%-confidence interval [CI] [0.19; 0.62], time: SMD 0.62, CI [0.33; 0.91]) and vice versa (composite: SMD 0.66, CI [0.33; 0.99], time [basic skills]: SMD 0.36, CI [0.01; 0.72]). No skill transfer was seen from open to robot-assisted surgery with limited available data. CONCLUSION: Technical surgical skills can be transferred from laparoscopic to robot-assisted surgery and vice versa. Robot-assisted and laparoscopic surgical skills training and credentialing should not be regarded separately, but a reasonable combination could shorten overall training times and increase efficiency. Previous experience in open surgery should not be considered as an imperative prerequisite for training in robot-assisted surgery. Recommendations for studies assessing skill transfer are proposed to increase comparability and significance of future studies. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42018104507.

Educational challenges and opportunities for the future generation of surgeons: a scoping review.

PURPOSE: Surgery offers exciting opportunities but comes with demanding challenges that require attention from both surgical program administrators and aspiring surgeons. The hashtag #NoTrainingTodayNoSurgeonsTomorrow on 𝕏 (previously Twitter) underscores the importance of ongoing training. Our scoping review identifies educational challenges and opportunities for the next generation of surgeons, analyzing existing studies and filling gaps in the literature. METHODS: Following the PRISMA guidelines, MEDLINE/PubMed was searched in February 2022, using the MeSH terms "surgeons/education," for articles in English or German on general, abdominal, thoracic, vascular, and hand surgery and traumatology targeting medical students, surgical residents, future surgeons, and fellows. RESULTS: The initial search yielded 1448 results. After a step-by-step evaluation process, 32 publications remained for complete review. Three main topics emerged: surgical innovations and training (n = 7), surgical culture and environment (n = 19), and mentoring (n = 6). The articles focusing on surgical innovations and training mainly described the incorporation of structured surgical training methods and program initiatives. Articles on surgical culture examined residents' burnout, well-being, and gender issues. Challenges faced by women, including implicit bias and sexual harassment, were highlighted. Regarding mentoring, mentees' needs, training challenges, and the qualities expected of both mentors and mentees were addressed. CONCLUSION: At a time of COVID-19-driven surgical innovations, the educational and working environment of the new generation of surgeons is changing. Robotic technology and other innovations require future surgeons to acquire additional technological and digital expertise. With regard to the cultural aspects of training, surgery needs to adapt curricula to meet the demands of the new generation of surgeons, but even more it has to transform its culture.

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.

Hepatic Artery Infusion Chemotherapy for Primary and Secondary Malignancies of the Liver: State of the Art and Current High-Level Evidence.

BACKGROUND: Hepatic artery infusion chemotherapy (HAI) has been proposed as a valuable adjunct for multimodal therapy of primary and secondary liver malignancies. This review provides an overview of the currently available evidence of HAI, taking into account tumor response and long-term oncologic outcome. SUMMARY: In colorectal liver metastases (CRLM), HAI in combination with systemic therapy leads to high response rates (85-90%) and conversion to resectablity in primary unresectable disease in up to 50%. HAI in combination with systemic therapy in CRLM in the adjuvant setting shows promising long-term outcomes with up to 50% 10-year survival in a large, non-randomized single-center cohort. For hepatocellular carcinoma patients, response rates as high as 20-40% have been reported for HAI and long-term outcomes compare well to other therapies. Similarly, survival for patients with unresectable intrahepatic cholangiocarcinoma 3 years after treatment with HAI is reported as high as 34%, which compares well to trials of systemic therapy where 3-year survival is usually below 5%. However, evidence is mainly limited by highly selected, heterogenous patient groups, and outdated chemotherapy regimens. The largest body of evidence stems from small, often non-randomized cohorts, predominantly from highly specialized single centers. KEY MESSAGE: In well-selected patients with primary and secondary liver malignancies, HAI might improve response rates and, possibly, long-term survival. Results of ongoing randomized trials will show whether a wider adoption of HAI is justified, particularly to increase rates of resectability in advanced malignant diseases confined to the liver.

Effects of endoluminal vacuum sponge therapy on the perfusion of gastric conduit in a porcine model for esophagectomy.

BACKGROUND: After esophagectomy, the postoperative rate of anastomotic leakage is up to 30% and is the main driver of postoperative morbidity. Contemporary management includes endoluminal vacuum sponge therapy (EndoVAC) with good success rates. Vacuum therapy improves tissue perfusion in superficial wounds, but this has not been shown for gastric conduits. This study aimed to assess gastric conduit perfusion with EndoVAC in a porcine model for esophagectomy. MATERIAL AND METHODS: A porcine model (n = 18) was used with gastric conduit formation and induction of ischemia at the cranial end of the gastric conduit with measurement of tissue perfusion over time. In three experimental groups EndoVAC therapy was then used in the gastric conduit (- 40, - 125, and - 200 mmHg). Changes in tissue perfusion and tissue edema were assessed using hyperspectral imaging. The study was approved by local authorities (Project License G-333/19, G-67/22). RESULTS: Induction of ischemia led to significant reduction of tissue oxygenation from 65.1 ± 2.5% to 44.7 ± 5.5% (p < 0.01). After EndoVAC therapy with - 125 mmHg a significant increase in tissue oxygenation to 61.9 ± 5.5% was seen after 60 min and stayed stable after 120 min (62.9 ± 9.4%, p < 0.01 vs tissue ischemia). A similar improvement was seen with EndoVAC therapy at - 200 mmHg. A nonsignificant increase in oxygenation levels was also seen after therapy with - 40 mmHg, from 46.3 ± 3.4% to 52.5 ± 4.3% and 53.9 ± 8.1% after 60 and 120 min respectively (p > 0.05). An increase in tissue edema was observed after 60 and 120 min of EndoVAC therapy with - 200 mmHg but not with - 40 and - 125 mmHg. CONCLUSIONS: EndoVAC therapy with a pressure of - 125 mmHg significantly increased tissue perfusion of ischemic gastric conduit. With better understanding of underlying physiology the optimal use of EndoVAC therapy can be determined including a possible preemptive use for gastric conduits with impaired arterial perfusion or venous congestion.

Short-term Outcomes of Robotic Versus Open Pancreatoduodenectomy: Propensity Score-matched Analysis.

OBJECTIVE: The goal of the current study was to investigate the perioperative outcomes of robotic pancreaticoduodenectomy (RPD) and open pancreaticoduodenectomy (OPD) in a high-volume center. BACKGROUND: Despite RPDs prospective advantages over OPD, current evidence comparing the 2 has been limited and has prompted further investigation. The aim of this study was to compare both approaches while including the learning curve phase for RPD. METHODS: A 1:1 propensity score-matched analysis of a prospective database of RPD with OPD (2017-2022) at a high-volume center was performed. The main outcomes were overall- and pancreas-specific complications. RESULTS: Of 375 patients who underwent PD (OPD n=276; RPD n=99), 180 were included in propensity score-matched analysis (90 per group). RPD was associated with less blood loss [500 (300-800) vs 750 (400-1000) mL; P =0.006] and more patients without a complication (50% vs 19%; P <0.001). Operative time was longer [453 (408-529) vs 306 (247-362) min; P <0.001]; in patients with ductal adenocarcinoma, fewer lymph nodes were harvested [24 (18-27) vs 33 (27-39); P <0.001] with RPD versus OPD. There were no significant differences for major complications (38% vs 47%; P =0.291), reoperation rate (14% vs 10%; P =0.495), postoperative pancreatic fistula (21% vs 23%; P =0.858), and patients with the textbook outcome (62% vs 55%; P =0.452). CONCLUSIONS: Including the learning phase, RPD can be safely implemented in high-volume settings and shows potential for improved perioperative outcomes versus OPD. Pancreas-specific morbidity was unaffected by the robotic approach. Randomized trials with specifically trained pancreatic surgeons and expanded indications for the robotic approach are needed.

Intraoperative liver deformation and organ motion caused by ventilation, laparotomy, and pneumoperitoneum in a porcine model for image-guided liver surgery.

BACKGROUND: Image-guidance promises to make complex situations in liver interventions safer. Clinical success is limited by intraoperative organ motion due to ventilation and surgical manipulation. The aim was to assess influence of different ventilatory and operative states on liver motion in an experimental model. METHODS: Liver motion due to ventilation (expiration, middle, and full inspiration) and operative state (native, laparotomy, and pneumoperitoneum) was assessed in a live porcine model (n = 10). Computed tomography (CT)-scans were taken for each pig for each possible combination of factors. Liver motion was measured by the vectors between predefined landmarks along the hepatic vein tree between CT scans after image segmentation. RESULTS: Liver position changed significantly with ventilation. Peripheral regions of the liver showed significantly higher motion (maximal Euclidean motion 17.9 ± 2.7 mm) than central regions (maximal Euclidean motion 12.6 ± 2.1 mm, p < 0.001) across all operative states. The total average motion measured 11.6 ± 0.7 mm (p < 0.001). Between the operative states, the position of the liver changed the most from native state to pneumoperitoneum (14.6 ± 0.9 mm, p < 0.001). From native state to laparotomy comparatively, the displacement averaged 9.8 ± 1.2 mm (p < 0.001). With pneumoperitoneum, the breath-dependent liver motion was significantly reduced when compared to other modalities. Liver motion due to ventilation was 7.7 ± 0.6 mm during pneumoperitoneum, 13.9 ± 1.1 mm with laparotomy, and 13.5 ± 1.4 mm in the native state (p < 0.001 in all cases). CONCLUSIONS: Ventilation and application of pneumoperitoneum caused significant changes in liver position. Liver motion was reduced but clearly measurable during pneumoperitoneum. Intraoperative guidance/navigation systems should therefore account for ventilation and intraoperative changes of liver position and peripheral deformation.

An international Delphi consensus for surgical quality assessment of lymphadenectomy and anastomosis in minimally invasive total gastrectomy for gastric cancer.

BACKGROUND: Minimally invasive total gastrectomy (MITG) is a mainstay for curative treatment of patients with gastric cancer. To define and standardize optimal surgical techniques and further improve clinical outcomes through the enhanced MITG surgical quality, there must be consensus on the key technical steps of lymphadenectomy and anastomosis creation, which is currently lacking. This study aimed to determine an expert consensus from an international panel regarding the technical aspects of the performance of MITG for oncological indications using the Delphi method. METHODS: A 100-point scoping survey was created based on the deconstruction of MITG into its key technical steps through local and international expert opinion and literature evidence. An international expert panel comprising upper gastrointestinal and general surgeons participated in multiple rounds of a Delphi consensus. The panelists voted on the issues concerning importance, difficulty, or agreement using an online questionnaire. A priori consensus standard was set at > 80% for agreement to a statement. Internal consistency and reliability were evaluated using Cronbach's α. RESULTS: Thirty expert upper gastrointestinal and general surgeons participated in three online Delphi rounds, generating a final consensus of 41 statements regarding MITG for gastric cancer. The consensus was gained from 22, 12, and 7 questions from Delphi rounds 1, 2, and 3, which were rephrased into the 41 statetments respectively. For lymphadenectomy and aspects of anastomosis creation, Cronbach's α for round 1 was 0.896 and 0.886, and for round 2 was 0.848 and 0.779, regarding difficulty or importance. CONCLUSIONS: The Delphi consensus defined 41 steps as crucial for performing a high-quality MITG for oncological indications based on the standards of an international panel. The results of this consensus provide a platform for creating and validating surgical quality assessment tools designed to improve clinical outcomes and standardize surgical quality in MITG.