Quality-of-life outcomes of the ROBOtic-assisted versus Conventional Open Partial nephrectomy (ROBOCOP) II trial.

OBJECTIVES: To comprehensively compare quality-of-life (QoL) outcomes between open partial nephrectomy (OPN) and robot-assisted PN (RAPN) from the randomised ROBOtic-assisted versus Conventional Open Partial nephrectomy (ROBOCOP) II trial, as QoL data comparing OPN and RAPN are virtually non-existent, especially not from randomised controlled trials (RCTs). PATIENTS AND METHODS: The ROBOCOP II was a single-centre, open-label RCT between OPN and RAPN. The pre-planned analyses of QoL outcomes are presented. Data were analysed descriptively in a modified intention-to-treat population. RESULTS: A total of 50 patients underwent surgery. At postoperative Day 90 (POD90), there was no significant difference for the Kidney Disease Quality of Life-Short Form questionnaire score (mean [sd] OPN 72 [20] vs RAPN 76 [15], P = 0.850), while there were advantages for RAPN in the subdomains of 'Pain' (P = 0.006) and 'Physical functioning' (P = 0.011) immediately after surgery. For the European Organisation for Research and Treatment of Cancer quality of life questionnaire 30-item core there were overall advantages directly after surgery (mean [sd] score OPN 63 [20] vs RAPN 75 [17], P = 0.031), as well as for the subdomains 'Fatigue' (P = 0.026), 'Pain' (P = 0.002) and 'Constipation' (P = 0.045) but no differences at POD90. There were no differences for the EuroQoL five Dimensions five Levels questionnaire at POD90 (mean [sd] score OPN 70 [22] vs RAPN 72 [17], P = 1.0) or at any other time point. Finally, no significant differences were found for the overall Convalescence and Recovery Evaluation questionnaire score at POD90 (mean [sd] OPN 84 [13] vs RAPN 86 [10], P = 0.818) but less pain in the RAPN group (P = 0.017) directly after surgery. CONCLUSIONS: Pain and physical functioning as subdomains of QoL are improved after RAPN compared to OPN in the early postoperative course, while there are no differences anymore after 3 months.

Pulse modulation in En-Bloc HoLEP: does it really matter? A propensity score matched analysis.

INTRODUCTION: Holmium laser enucleation of the prostate (HoLEP) is an established option in the surgical treatment of benign prostatic hyperplasia. Pulse modulation, such as MOSES® technology, has recently been introduced and may offer potential advantages in HoLEP. METHODS: Perioperative data from 117 patients who underwent MOSES® laser enucleation of the prostate (MoLEP) were collected. Propensity score matching using prostate volume, age, body mass index (BMI), and anticoagulant intake was performed using a database of 237 patients treated with HoLEP. In total, 234 patients were included in the analysis. RESULTS: Prostate volume (104 vs. 102 ml), age (70 vs. 71 years), BMI (27 vs. 27), and anticoagulant intake (34 vs. 35%) did not differ significantly between the groups. There were no significant differences in operation time (61.5 vs. 58.1 min, p = 0.42), enucleation efficiency (2.5 vs. 2.6 g/min, p = 0.74), hemostasis time (7.8 vs. 8 min, p = 0.75) and hemoglobin drop (0.9 vs. 0.7 mg/dl, p = 0.48). The complication rates were low in both groups (16.2% for HoLEP and 17.1% for MoLEP). No differences were noted in the Clavien-Dindo Classification (p = 0.63) and the Comprehensive Complication Index (p = 0.24). The rate of complications > CDC IIIa was 0.9% for HoLEP (endoscopic coagulation) and 1.7% for MoLEP (2 cases of endoscopic coagulation). No transfusions were administered. CONCLUSION: Overall, the enucleation efficiency was high in both groups and the procedure time was short. HoLEP is an efficient and safe treatment option in experienced hands, regardless of the use of pulse modulation technology.

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.

Cyclin A2 Expression as Predictive Biomarker in Muscle-Invasive Upper Tract Urothelial Carcinoma.

INTRODUCTION: The aim was to evaluate the prognostic value of altered Cyclin A2 (CCNA2) gene expression in upper tract urothelial carcinoma (UTUC) and to assess its predictive potential as a prognostic factor for overall survival (OS) and disease-free survival. METHODS: 62 patients who underwent surgical treatment for UTUC were included. Gene expression of CCNA2, MKI67, and p53 was analyzed by quantitative reverse transcriptase polymerase chain reaction. Survival analyses were performed using the Kaplan-Meier method and the log-rank test. For Cox regression analyses, uni- and multivariable hazard ratios were calculated. Spearman correlation was used to analyze correlation of CCNA2 expression with MKI67 and p53. RESULTS: The median age of the cohort was 73 years, and it consisted of 48 males (77.4%) and 14 females (22.6%). Patients with high CCNA2 expression levels showed longer OS (HR 0.33; 95% CI: 0.15-0.74; p = 0.0073). Multivariable Cox regression analyses identified CCNA2 overexpression (HR 0.37; 95% CI: 0.16-0.85; p = 0.0189) and grading G2 (vs. G3) (HR 0.39; 95% CI: 0.17-0.87; p = 0.0168) to be independent predictors for longer OS. CCNA2 expression correlated positively with MKI67 expression (Rho = 0.4376, p = 0.0005). CONCLUSION: Low CCNA2 expression is significantly associated with worse OS. Thus, CCNA2 might serve as a potential biomarker in muscle-invasive UTUC and may be used to characterize a subset of patients having an unfavorable outcome and for future risk assessment scores.

A self-supervised vision transformer to predict survival from histopathology in renal cell carcinoma.

PURPOSE: To develop and validate an interpretable deep learning model to predict overall and disease-specific survival (OS/DSS) in clear cell renal cell carcinoma (ccRCC). METHODS: Digitised haematoxylin and eosin-stained slides from The Cancer Genome Atlas were used as a training set for a vision transformer (ViT) to extract image features with a self-supervised model called DINO (self-distillation with no labels). Extracted features were used in Cox regression models to prognosticate OS and DSS. Kaplan-Meier for univariable evaluation and Cox regression analyses for multivariable evaluation of the DINO-ViT risk groups were performed for prediction of OS and DSS. For validation, a cohort from a tertiary care centre was used. RESULTS: A significant risk stratification was achieved in univariable analysis for OS and DSS in the training (n = 443, log rank test, p < 0.01) and validation set (n = 266, p < 0.01). In multivariable analysis, including age, metastatic status, tumour size and grading, the DINO-ViT risk stratification was a significant predictor for OS (hazard ratio [HR] 3.03; 95%-confidence interval [95%-CI] 2.11-4.35; p < 0.01) and DSS (HR 4.90; 95%-CI 2.78-8.64; p < 0.01) in the training set but only for DSS in the validation set (HR 2.31; 95%-CI 1.15-4.65; p = 0.02). DINO-ViT visualisation showed that features were mainly extracted from nuclei, cytoplasm, and peritumoural stroma, demonstrating good interpretability. CONCLUSION: The DINO-ViT can identify high-risk patients using histological images of ccRCC. This model might improve individual risk-adapted renal cancer therapy in the future.

Telestration with augmented reality improves the performance of the first ten ex vivo porcine laparoscopic cholecystectomies: a randomized controlled study.

INTRODUCTION: The learning curve in minimally invasive surgery (MIS) is steep compared to open surgery. One of the reasons is that training in the operating room in MIS is mainly limited to verbal instructions. The iSurgeon telestration device with augmented reality (AR) enables visual instructions, guidance, and feedback during MIS. This study aims to compare the effects of the iSurgeon on the training of novices performing repeated laparoscopic cholecystectomy (LC) on a porcine liver compared to traditional verbal instruction methods. METHODS: Forty medical students were randomized into the iSurgeon and the control group. The iSurgeon group performed 10 LCs receiving interactive visual guidance. The control group performed 10 LCs receiving conventional verbal guidance. The performance assessment using Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores, the total operating time, and complications were compared between the two groups. RESULTS: The iSurgeon group performed LCs significantly better (global GOALS 17.3 ± 2.6 vs. 16 ± 2.6, p ≤ 0.001, LC specific GOALS 7 ± 2 vs. 5.9 ± 2.1, p ≤ 0.001, global OSATS 25.3 ± 4.3 vs. 23.5 ± 3.9, p ≤ 0.001, LC specific OSATS scores 50.8 ± 11.1 vs. 41.2 ± 9.4, p ≤ 0.001) compared to the control group. The iSurgeon group had significantly fewer intraoperative complications in total (2.7 ± 2.0 vs. 3.6 ± 2.0, p ≤ 0.001) than the control group. There was no difference in operating time (79.6 ± 25.7 vs. 84.5 ± 33.2 min, p = 0.087). CONCLUSION: Visual guidance using the telestration device with AR, iSurgeon, improves performance and lowers the complication rates in LCs in novices compared to conventional verbal expert guidance.

Video-based training of situation awareness enhances minimally invasive surgical performance: a randomized controlled trial.

BACKGROUND: Many training curricula were introduced to deal with the challenges that minimally invasive surgery (MIS) presents to the surgeon. Situational awareness (SA) is the ability to process information effectively. It depends on general cognitive abilities and can be divided into three steps: perceiving cues, linking cues to knowledge and understanding their relevance, and predicting possible outcomes. Good SA is crucial to predict and avoid complications and respond efficiently. This study aimed to introduce the concept of SA into laparoscopic training. METHODS: This is a prospective, randomized, controlled study conducted at the MIS Training Center of Heidelberg University Hospital. Video sessions showing the steps of the laparoscopic cholecystectomy (LC) were used for cognitive training. The intervention group trained SA with interposed questions inserted into the video clips. The identical video clips, without questions, were presented to the control group. Performance was assessed with validated scores such as the Objective Structured Assessment of Technical Skills (OSATS) during LC. RESULTS: 72 participants were enrolled of which 61 were included in the statistical analysis. The SA-group performed LC significantly better (OSATS-Score SA: 67.0 ± 11.5 versus control: 59.1 ± 14.0, p value = 0.034) and with less errors (error score SA: 3.5 ± 1.9 versus control: 4.7 ± 2.0, p value = 0.027). No difference in the time taken to complete the procedure was found. The benefit assessment analysis showed no difference between the groups in terms of perceived learning effect, concentration, or expediency. However, most of the control group indicated retrospectively that they believed they would have benefitted from the intervention. CONCLUSION: This study suggests that video-based SA training for laparoscopic novices has a positive impact on performance and error rate. SA training should thus be included as one aspect besides simulation and real cases in a multimodal curriculum to improve the efficiency of laparoscopic surgical skills training.

Force-based assessment of tissue handling skills in simulation training for robot-assisted surgery.

INTRODUCTION: Although robotic-assisted surgery is increasingly performed, objective assessment of technical skills is lacking. The aim of this study is to provide validity evidence for objective assessment of technical skills for robotic-assisted surgery. METHODS: An international multicenter study was conducted with participants from the academic hospitals Heidelberg University Hospital (Germany, Heidelberg) and the Amsterdam University Medical Centers (The Netherlands, Amsterdam). Trainees with distinctly different levels of robotic surgery experience were divided into three groups (novice, intermediate, expert) and enrolled in a training curriculum. Each trainee performed six trials of a standardized suturing task using the da Vinci Surgical System. Using the ForceSense system, five force-based parameters were analyzed, for objective assessment of tissue handling skills. Mann-Whitney U test and linear regression were used to analyze performance differences and the Wilcoxon signed-rank test to analyze skills progression. RESULTS: A total of 360 trials, performed by 60 participants, were analyzed. Significant differences between the novices, intermediates and experts were observed regarding the total completion time (41 s vs 29 s vs 22 s p = 0.003), mean non zero force (29 N vs 33 N vs 19 N p = 0.032), maximum impulse (40 Ns vs 31 Ns vs 20 Ns p = 0.001) and force volume (38 N3 vs 32 N3 vs 22 N3 p = 0.018). Furthermore, the experts showed better results in mean non-zero force (22 N vs 13 N p = 0.015), maximum impulse (24 Ns vs 17 Ns p = 0.043) and force volume (25 N3 vs 16 N3 p = 0.025) compared to the intermediates (p ≤ 0.05). Lastly, learning curve improvement was observed for the total task completion time, mean non-zero force, maximum impulse and force volume (p ≤ 0.05). CONCLUSION: Construct validity for force-based assessment of tissue handling skills in robot-assisted surgery is established. It is advised to incorporate objective assessment and feedback in robot-assisted surgery training programs to determine technical proficiency and, potentially, to prevent tissue trauma.

Telestration with augmented reality improves surgical performance through gaze guidance.

BACKGROUND: In minimally invasive surgery (MIS), trainees need to learn how to interpret the operative field displayed on the laparoscopic screen. Experts currently guide trainees mainly verbally during laparoscopic procedures. A newly developed telestration system with augmented reality (iSurgeon) allows the instructor to display hand gestures in real-time on the laparoscopic screen in augmented reality to provide visual expert guidance (telestration). This study analysed the effect of telestration guided instructions on gaze behaviour during MIS training. METHODS: In a randomized-controlled crossover study, 40 MIS naive medical students performed 8 laparoscopic tasks with telestration or with verbal instructions only. Pupil Core eye-tracking glasses were used to capture the instructor's and trainees' gazes. Gaze behaviour measures for tasks 1-7 were gaze latency, gaze convergence and collaborative gaze convergence. Performance measures included the number of errors in tasks 1-7 and trainee's ratings in structured and standardized performance scores in task 8 (ex vivo porcine laparoscopic cholecystectomy). RESULTS: There was a significant improvement 1-7 on gaze latency [F(1,39) = 762.5, p < 0.01, ηp2 = 0.95], gaze convergence [F(1,39) = 482.8, p < 0.01, ηp2 = 0.93] and collaborative gaze convergence [F(1,39) = 408.4, p < 0.01, ηp2 = 0.91] upon instruction with iSurgeon. The number of errors was significantly lower in tasks 1-7 (0.18 ± 0.56 vs. 1.94 ± 1.80, p < 0.01) and the score ratings for laparoscopic cholecystectomy were significantly higher with telestration (global OSATS: 29 ± 2.5 vs. 25 ± 5.5, p < 0.01; task-specific OSATS: 60 ± 3 vs. 50 ± 6, p < 0.01). CONCLUSIONS: Telestration with augmented reality successfully improved surgical performance. The trainee's gaze behaviour was improved by reducing the time from instruction to fixation on targets and leading to a higher convergence of the instructor's and the trainee's gazes. Also, the convergence of trainee's gaze and target areas increased with telestration. This confirms augmented reality-based telestration works by means of gaze guidance in MIS and could be used to improve training outcomes.

Crossover-effects in technical skills between laparoscopy and robot-assisted surgery.

INTRODUCTION: Robot-assisted surgery is often performed by experienced laparoscopic surgeons. However, this technique requires a different set of technical skills and surgeons are expected to alternate between these approaches. The aim of this study is to investigate the crossover effects when switching between laparoscopic and robot-assisted surgery. METHODS: An international multicentre crossover study was conducted. Trainees with distinctly different levels of experience were divided into three groups (novice, intermediate, expert). Each trainee performed six trials of a standardized suturing task using a laparoscopic box trainer and six trials using the da Vinci surgical robot. Both systems were equipped with the ForceSense system, measuring five force-based parameters for objective assessment of tissue handling skills. Statistical comparison was done between the sixth and seventh trial to identify transition effects. Unexpected changes in parameter outcomes after the seventh trial were further investigated. RESULTS: A total of 720 trials, performed by 60 participants, were analysed. The expert group increased their tissue handling forces with 46% (maximum impulse 11.5 N/s to 16.8 N/s, p = 0.05), when switching from robot-assisted surgery to laparoscopy. When switching from laparoscopy to robot-assisted surgery, intermediates and experts significantly decreased in motion efficiency (time (sec), resp. 68 vs. 100, p = 0.05, and 44 vs. 84, p = 0.05). Further investigation between the seventh and ninth trial showed that the intermediate group increased their force exertion with 78% (5.1 N vs. 9.1 N, p = 0.04), when switching to robot-assisted surgery. CONCLUSION: The crossover effects in technical skills between laparoscopic and robot-assisted surgery are highly depended on the prior experience with laparoscopic surgery. Where experts can alternate between approaches without impairment of technical skills, novices and intermediates should be aware of decay in efficiency of movement and tissue handling skills that could impact patient safety. Therefore, additional simulation training is advised to prevent from undesired events.

Robotic-assisted versus laparoscopic bowel anastomoses: randomized crossover in vivo experimental study.

BACKGROUND: Initial learning curves are potentially shorter in robotic-assisted surgery (RAS) than in conventional laparoscopic surgery (LS). There is little evidence to support this claim. Furthermore, there is limited evidence how skills from LS transfer to RAS. METHODS: A randomized controlled, assessor blinded crossover study to compare how RAS naïve surgeons (n = 40) performed linear-stapled side-to-side bowel anastomoses in an in vivo porcine model with LS and RAS. Technique was rated using the validated anastomosis objective structured assessment of skills (A-OSATS) score and the conventional OSATS score. Skill transfer from LS to RAS was measured by comparing the RAS performance of LS novices and LS experienced surgeons. Mental and physical workload was measured with the NASA-task load index (NASA-Tlx) and the Borg-scale. OUTCOMES: In the overall cohort, there were no differences between RAS and LS for surgical performance (A-OSATS, time, OSATS). Surgeons that were naïve in both LS and RAS had significantly higher A-OSATS scores in RAS (Mean (Standard deviation (SD)): LS: 48.0 ± 12.1; RAS: 52.0 ± 7.5); p = 0.044) mainly deriving from better bowel positioning (LS: 8.7 ± 1.4; RAS: 9.3 ± 1.0; p = 0.045) and closure of enterotomy (LS: 12.8 ± 5.5; RAS: 15.6 ± 4.7; p = 0.010). There was no statistically significant difference in how LS novices and LS experienced surgeons performed in RAS [Mean (SD): novices: 48.9 ± 9.0; experienced surgeons: 55.9 ± 11.0; p = 0.540]. Mental and physical demand was significantly higher after LS. CONCLUSION: The initial performance was improved for RAS versus LS for linear stapled bowel anastomosis, whereas workload was higher for LS. There was limited transfer of skills from LS to RAS.

Perioperative Antibiotic Prophylaxis in Radical Prostatectomy: "Single-Shot" versus Multiday Regimen.

INTRODUCTION: Perioperative antibiotic prophylaxis (AP) is common in radical prostatectomy (RP). Yet there is no standard recommendation in international guidelines due to poor evidence. It is of great importance that these perioperative AP are sufficiently checked and systemically validated. The objective of this study was to determine whether a "single-shot" (single-use) perioperative AP yields equivalent results compared to a multiday prophylaxis in RP regarding postoperative wound infections and urinary tract infections. METHODS: 376 patients treated by RP at the University Medical Centre Mannheim, from 2014 to 2016, were included in this retrospective study. RP was performed either in a robotic-assisted or open manner. One group received an intravenous dose of perioperative AP with either ciprofloxacin or levofloxacin, continued by an oral dose of AP with ciprofloxacin or levofloxacin until catheter removal, while the other group received a single-shot intravenous perioperative AP with either ciprofloxacin or cefuroxime. RESULTS: There was no significant difference regarding the occurrence of postoperative infections between both AP regimes (p = 0.5). Age, body mass index, and ASA classification did not differ significantly between both groups (p > 0.25). Except for surgery time (p < 0.05), perioperative parameters, such as the preoperative presence of germ-free urine culture, length of hospital stay, catheter time, drain lay time, Gleason score, and TNM stadium, did not differ significantly. CONCLUSION: The present study shows that perioperative single-shot AP does not entail any disadvantage compared to the multiday AP in terms of postoperative infections after RP.

Predicting Complexity in Transurethral Resection of Bladder Tumours: External Validation and Modification of the Bladder Complexity Score.

INTRODUCTION: First external validation of the Bladder Complexity Score (BCS) for predicting complex transurethral resection of bladder tumours (TURBT). METHODS: For BCS calculation, TURBTs performed at our institution between January 2018 and December 2019 were reviewed for the presence of preoperative characteristics listed in the Bladder Complexity Checklist (BCC). Receiver operating characteristics (ROC) analysis was used for BCS validation. To establish a modified BCS (mBCS) with maximum area under the curve (AUC), multivariable logistic regression (MLR) analysis was performed with all BCC-characteristics for different definitions of complex TURBT. RESULTS: 723 TURBTs were included in statistical analyses. Cohort's mean BCS was 11.2 ± 2.4 points (range: 5.5-22 points). In ROC analysis, BCS could not predict complex TURBT (AUC 0.573 [95% CI: 0.517-0.628]). MLR identified tumour size (OR 2.662, p < 0.001), and tumour number > 10 (OR 6.390, p = 0.032) as sole predictors for the modified endpoint of complex TURBT defined as a procedure meeting > 1 criterion: incomplete resection, surgery > 1 h, intraoperative complication, postoperative complications Clavien-Dindo ≥ III. mBCS increased the prediction to an AUC of 0.770 (95% CI: 0.667-0.874). CONCLUSION: In this first external validation, BCS remained an insufficient predictor of complex TURBT. mBCS requires reduced parameters, is more predictive and easier to apply in clinical practice.

Perioperative Outcome of Thulium Laser Enucleation of the Prostate versus Robot-Assisted Simple Prostatectomy: A Propensity Score-Matched Analysis.

INTRODUCTION: The aim of this study was to investigate and compare clinical safety and efficiency of Thulium laser enucleation of the prostate (ThuLEP) and robot-assisted simple prostatectomy (RASP) for the treatment of large gland benign prostatic hyperplasia in a tertiary care center. METHODS: Perioperative data of 39 patients who underwent RASP in our institution from 2015 to 2021 was collected. Propensity score matching using prostate volume, patient age, and body mass index (BMI) was performed from a database of 1,100 Patients treated by ThuLEP from 2009 to 2021. A total of 76 patients were matched. Preoperative parameters such as BMI, age, and prostate volume, as well as intra- and postoperative parameters such as operation time, resection weight, transfusion rate, postoperative catheterization time, length of hospital stay (LoS), hemoglobin drop, postoperative urinary retention (PUR), Clavien-Dindo Classification (CDC), and the Combined Complication Index (CCI), were evaluated. RESULTS: There was no difference in mean hemoglobin drop (2.2 vs. 1.9 g/dL, p = 0.34), yet endoscopic surgery showed superiority in mean operation time (109 vs. 154 min, p < 0.001), mean postoperative catheterization time (3.3 vs. 7.2 days, p < 0.001), and mean LOS (5.4 vs. 8.4 days, p < 0.001). Complication rates evaluated by CDC (p = 0.11) and CCI (p = 0.89) were similar in both groups. Within the documented complications, transfusion rate (0 vs. 3, p = 0.08) and the occurrence of PUR (1 vs. 2, p = 0.5) showed no significant difference. CONCLUSION: ThuLEP and RASP show similar perioperative efficacy and a low rate of complications. ThuLEP had shorter operation times, shorter catheterization time, and a shorter LoS.

Effects of individualised positive end-expiratory pressure titration on respiratory and haemodynamic parameters during the Trendelenburg position with pneumoperitoneum: A randomised crossover physiologic trial.

BACKGROUND: The Trendelenburg position with pneumoperitoneum during surgery promotes dorsobasal atelectasis formation, which impairs respiratory mechanics and increases lung stress and strain. Positive end-expiratory pressure (PEEP) can reduce pulmonary inhomogeneities and preserve end-expiratory lung volume (EELV), resulting in decreased inspiratory strain and improved gas-exchange. The optimal intraoperative PEEP strategy is unclear. OBJECTIVES: To compare the effects of individualised PEEP titration strategies on set PEEP levels and resulting transpulmonary pressures, respiratory mechanics, gas-exchange and haemodynamics during Trendelenburg position with pneumoperitoneum. DESIGN: Prospective, randomised, crossover single-centre physiologic trial. SETTING: University hospital. PATIENTS: Thirty-six patients receiving robot-assisted laparoscopic radical prostatectomy. INTERVENTIONS: Randomised sequence of three different PEEP strategies: standard PEEP level of 5 cmH 2 O (PEEP 5 ), PEEP titration targeting a minimal driving pressure (PEEP ΔP ) and oesophageal pressure-guided PEEP titration (PEEP Poeso ) targeting an end-expiratory transpulmonary pressure ( PTP ) of 0 cmH 2 O. MAIN OUTCOME MEASURES: The primary endpoint was the PEEP level when set according to PEEP ΔP and PEEP Poeso compared with PEEP of 5 cmH 2 O. Secondary endpoints were respiratory mechanics, lung volumes, gas-exchange and haemodynamic parameters. RESULTS: PEEP levels differed between PEEP ΔP , PEEP Poeso and PEEP5 (18.0 [16.0 to 18.0] vs. 20.0 [18.0 to 24.0]vs. 5.0 [5.0 to 5.0] cmH 2 O; P  < 0.001 each). End-expiratory PTP and lung volume were lower in PEEP ΔP compared with PEEP Poeso ( P  = 0.014 and P  < 0.001, respectively), but driving pressure, lung stress, as well as respiratory system and dynamic elastic power were minimised using PEEP ΔP ( P  < 0.001 each). PEEP ΔP and PEEP Poeso improved gas-exchange, but PEEP Poeso resulted in lower cardiac output compared with PEEP 5 and PEEP ΔP . CONCLUSION: PEEP ΔP ameliorated the effects of Trendelenburg position with pneumoperitoneum during surgery on end-expiratory PTP and lung volume, decreased driving pressure and dynamic elastic power, as well as improved gas-exchange while preserving cardiac output. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00028559, date of registration 2022/04/27). https://drks.de/search/en/trial/DRKS00028559.

Development of biotissue training models for anastomotic suturing in pancreatic surgery.

BACKGROUND: Anastomotic suturing is the Achilles heel of pancreatic surgery. Especially in laparoscopic and robotically assisted surgery, the pancreatic anastomosis should first be trained outside the operating room. Realistic training models are therefore needed. METHODS: Models of the pancreas, small bowel, stomach, bile duct, and a realistic training torso were developed for training of anastomoses in pancreatic surgery. Pancreas models with soft and hard textures, small and large ducts were incrementally developed and evaluated. Experienced pancreatic surgeons (n = 44) evaluated haptic realism, rigidity, fragility of tissues, and realism of suturing and knot tying. RESULTS: In the iterative development process the pancreas models showed high haptic realism and highest realism in suturing (4.6 ± 0.7 and 4.9 ± 0.5 on 1-5 Likert scale, soft pancreas). The small bowel model showed highest haptic realism (4.8 ± 0.4) and optimal wall thickness (0.1 ± 0.4 on -2 to +2 Likert scale) and suturing behavior (0.1 ± 0.4). The bile duct models showed optimal wall thickness (0.3 ± 0.8 and 0.4 ± 0.8 on -2 to +2 Likert scale) and optimal tissue fragility (0 ± 0.9 and 0.3 ± 0.7). CONCLUSION: The biotissue training models showed high haptic realism and realistic suturing behavior. They are suitable for realistic training of anastomoses in pancreatic surgery which may improve patient outcomes.

Pancreatic surgery with or without drainage: propensity score-matched study.

BACKGROUND: A recent RCT has shown that routine intraoperative drain placement after pancreatoduodenectomy (PD) is not necessary. The aim was to confirm this in real-world conditions. METHODS: A propensity score-matched (PSM) analysis of patients with and without drainage after PD or distal pancreatectomy (DP) at a high-volume centre was undertaken. Main outcomes were complications and duration of hospital stay. Multivariable regression analysis was used to assessed which factors led to intraoperative drainage after the standard was changed from drain to no drain. RESULTS: Of 377 patients who underwent PD, 266 were included in PSM analysis. No drain was associated with fewer major complications (42 (31.6 per cent) versus 62 (46.6 per cent); P = 0.017), shorter duration of hospital stay (mean(s.d.) 14.7(8.5) versus 19.6(14.9) days; P = 0.001), and required fewer interventional drain placements (8.4 versus 19.8 per cent; P = 0.013). In PSM analysis after DP (112 patients), no drainage was associated with fewer clinically relevant postoperative pancreatic fistulas (9 versus 18 per cent; P = 0.016), fewer overall complications (mean(s.d.) comprehensive complication index score 15.9(15.4) versus 24.8(20.4); P = 0.012), and a shorter hospital stay (9.3(7.0) versus 13.5(9.9) days; P = 0.011). Multivisceral resection (OR 2.80, 95 per cent c.i. 1.10 to 7.59; P = 0.034) and longer operating times (OR 1.56, 1.04 to 2.36; P = 0.034) influenced the choice to place a drain after PD. Greater blood loss was associated with drainage after DP (OR 1.14, 1.02 to 1.30; P = 0.031). CONCLUSION: Standard pancreatic resections can be performed safely without drainage. Surgeons were more reluctant to omit drainage after complex pancreatic resections.

Pancreatic surgery has traditionally relied on the use of drains placed during surgery that should facilitate outflow of fluids from the operating site. This principle has recently been challenged by specially designed studies showing that patients who do not receive a drain may have fewer complications. The present study has demonstrated that these results also apply to routine clinical settings outside the constraints of surgical trials.

Development and validity evidence of an objective structured assessment of technical skills score for minimally invasive linear-stapled, hand-sewn intestinal anastomoses: the A-OSATS score.

INTRODUCTION: The aim of this study was to develop a reliable objective structured assessment of technical skills (OSATS) score for linear-stapled, hand-sewn closure of enterotomy intestinal anastomoses (A-OSATS). MATERIALS AND METHODS: The Delphi methodology was used to create a traditional and weighted A-OSATS score highlighting the more important steps for patient outcomes according to an international expert consensus. Minimally invasive novices, intermediates, and experts were asked to perform a minimally invasive linear-stapled intestinal anastomosis with hand-sewn closure of the enterotomy in a live animal model either laparoscopically or robot-assisted. Video recordings were scored by two blinded raters assessing intrarater and interrater reliability and discriminative abilities between novices (n = 8), intermediates (n = 24), and experts (n = 8). RESULTS: The Delphi process included 18 international experts and was successfully completed after 4 rounds. A total of 4 relevant main steps as well as 15 substeps were identified and a definition of each substep was provided. A maximum of 75 points could be reached in the unweighted A-OSATS score and 170 points in the weighted A-OSATS score respectively. A total of 41 anastomoses were evaluated. Excellent intrarater (r = 0.807-0.988, p < 0.001) and interrater (intraclass correlation coefficient = 0.923-0.924, p < 0.001) reliability was demonstrated. Both versions of the A-OSATS correlated well with the general OSATS and discriminated between novices, intermediates, and experts defined by their OSATS global rating scale. CONCLUSION: With the weighted and unweighted A-OSATS score, we propose a new reliable standard to assess the creation of minimally invasive linear-stapled, hand-sewn anastomoses based on an international expert consensus. Validity evidence in live animal models is provided in this study. Future research should focus on assessing whether the weighted A-OSATS exceeds the predictive capabilities of patient outcomes of the unweighted A-OSATS and provide further validity evidence on using the score on different anastomotic techniques in humans.

Value of Radiomics of Perinephric Fat for Prediction of Intraoperative Complexity in Renal Tumor Surgery.

INTRODUCTION: The aim of this study was to assess the value of computed tomography (CT)-based radiomics of perinephric fat (PNF) for prediction of surgical complexity. METHODS: Fifty-six patients who underwent renal tumor surgery were included. Radiomic features were extracted from contrast-enhanced CT. Machine learning models using radiomic features, the Mayo Adhesive Probability (MAP) score, and/or clinical variables (age, sex, and body mass index) were compared for the prediction of adherent PNF (APF), the occurrence of postoperative complications (Clavien-Dindo Classification ≥2), and surgery duration. Discrimination performance was assessed by the area under the receiver operating characteristic curve (AUC). In addition, the root mean square error (RMSE) and R2 (fraction of explained variance) were used as additional evaluation metrics. RESULTS: A single feature logit model containing "Wavelet-LHH-transformed GLCM Correlation" achieved the best discrimination (AUC 0.90, 95% confidence interval [CI]: 0.75-1.00) and lowest error (RMSE 0.32, 95% CI: 0.20-0.42) at prediction of APF. This model was superior to all other models containing all radiomic features, clinical variables, and/or the MAP score. The performance of uninformative benchmark models for prediction of postoperative complications and surgery duration were not improved by machine learning models. CONCLUSION: Radiomic features derived from PNF may provide valuable information for preoperative risk stratification of patients undergoing renal tumor surgery.

Machine Learning for Surgical Phase Recognition: A Systematic Review.

OBJECTIVE: To provide an overview of ML models and data streams utilized for automated surgical phase recognition. BACKGROUND: Phase recognition identifies different steps and phases of an operation. ML is an evolving technology that allows analysis and interpretation of huge data sets. Automation of phase recognition based on data inputs is essential for optimization of workflow, surgical training, intraoperative assistance, patient safety, and efficiency. METHODS: A systematic review was performed according to the Cochrane recommendations and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed, Web of Science, IEEExplore, GoogleScholar, and CiteSeerX were searched. Literature describing phase recognition based on ML models and the capture of intraoperative signals during general surgery procedures was included. RESULTS: A total of 2254 titles/abstracts were screened, and 35 full-texts were included. Most commonly used ML models were Hidden Markov Models and Artificial Neural Networks with a trend towards higher complexity over time. Most frequently used data types were feature learning from surgical videos and manual annotation of instrument use. Laparoscopic cholecystectomy was used most commonly, often achieving accuracy rates over 90%, though there was no consistent standardization of defined phases. CONCLUSIONS: ML for surgical phase recognition can be performed with high accuracy, depending on the model, data type, and complexity of surgery. Different intraoperative data inputs such as video and instrument type can successfully be used. Most ML models still require significant amounts of manual expert annotations for training. The ML models may drive surgical workflow towards standardization, efficiency, and objectiveness to improve patient outcome in the future. REGISTRATION PROSPERO: CRD42018108907.