Fundamental technical skills of EndoVascular Surgery: A preliminary study on its impact on skills and stress during procedures.

OBJECTIVES: Our objective is twofold: determining if simulation allows residents to reach proficient surgeons' performance concerning Fundamental technical skills of EndoVascular Surgery (FEVS) and to while investigating the effects of the program on surgeon's stress. MATERIAL & METHODS: Using a FEVS training simulator, 8 endovascular FEVS were performed by vascular surgery residents (simulator-naive (SNR) or simulator-experienced (SER)) and seniors. Total time needed to complete the 8 tasks, called Total Completion Time (TCT), was the main evaluation criterion. Analgesia Nociception Index (ANI), was monitored during simulation. Likert scale questionnaire was filled after each simulation. RESULTS: For each task, TCT was significantly lower for SER and seniors than SNR (p=0.0163). After only 5 simulations, SER were able to reach and even exceed the seniors' level in terms of TCT, with a median time of 10.8 minutes for SER and 11.9 minutes for seniors, and wire's movements with a median distance during cannulation of 4.44 m for SER and 4.17m for seniors. Seniors remained better than SER in terms of precise wire manipulation (wire movement after cannulation), 4.17m against 4.44m (3.72-5.96) respectively. Based on the Likert scale, stress analysis, seniors felt less stressed than both residents' groups (p=0.0618). Seniors' initial ANI and mean ANI over the session was were significantly lower than those of the residents, p=0.0358 and p=0.0250 respectively. CONCLUSION: We showed that 5 simulation sessions allowed residents to reach experienced surgeons' capacities on FEVS concerning TCT. Subjectively, seniors felt less stressed than residents, contrary to the results of our objective measures of stress.

Editor's Choice -- Type IIIb Endoleaks: Fabric Perforations of Explanted New Generation Endoprostheses.

OBJECTIVE: To analyse explanted endografts (EGs) and describe fabric degradation responsible for type IIIb endoleaks. METHODS: As part of the European collaborative retrieval programme, 32 EGs with fabric defects on macroscopic evaluation were selected. The explanted EGs were processed and studied based on the ISO 9001 certified standard protocol. It includes instructions on the collection, transportation, cleaning, and examination of explanted material. The precise analysis was performed with a digital microscope of 20 - 200 times magnification. Possible perforation mechanisms were assessed in stress tests. RESULTS: The median time to explantation of the 32 EGs was 54 months. The explants included 65 separate EG modules, with 46 (70.8%) having a combined 388 fabric perforations. Each EG had a median of 4.79 mm2 (interquartile range [IQR] 9.86 mm2) of cumulated hole area (an average of 0.13% of an EG's area). There were 239 (61.6%) expanded polytetrafluoroethylene (ePTFE; 11 EGs) and 149 (38.4%) polyethylene terephthalate (PET; 21 EGs) fabric ruptures, with no difference in hole distribution between these types of material. Overall, 126 (32.5%) stent related and 262 (67.5%) non-stent related fabric perforations were identified. Perforations caused by fabric fatigue in ePTFE (151, 63.2%) and material kinking in PET (41, 27.5%) were the most common. The stent related perforations were larger in size (0.80 mm2) than non-stent related perforations (0.19 mm2); p < .001. Wider interstent spaces and prolonged implantation duration were associated with an increased risk of stent related perforation development; p < .001 and p = .004, respectively. Large stent related perforations were also detected in the short term, suggesting mechanical issues as underlying causes. CONCLUSION: The fabric of EGs may degrade and lead to the development of perforations. The largest perforations are stent related. Their occurrence and size depend on the implantation time and the EG shape affected by arterial tortuosity. The conclusions are limited to the samples from a select explant group.

Calcification of Synthetic Vascular Grafts: A Systematic Review.

Objective: Calcification of vascular grafts, including polyethylene terephthalate (PET) and expanded polytetrafluoroethylene (ePTFE) grafts may contribute to graft failure, but is under reported. The aim of this study was to review the literature to assess whether vascular graft calcification is deleterious to vascular graft outcomes. Data sources: The Medline and Embase databases were searched. Review methods: A systematic literature search according to PRISMA Guidelines was performed using a combined search strategy of MeSH terms. The MeSH terms used were "calcification, physiologic", "calcinosis", "vascular grafting", "blood vessel prosthesis", "polyethylene terephthalates", and "polytetrafluoroethylene". Results: The systematic search identified 17 cases of PET graft calcification and 73 cases of ePTFE graft calcification over a 35 year period. All cases of PET graft calcification were reported in grafts explanted for graft failure. The majority of cases of ePTFE graft calcification were unexpectedly noted in grafts used during cardiovascular procedures and subsequently removed. Conclusion: Calcification of synthetic vascular grafts is under reported but can compromise the long term performance of the grafts. More data, including specific analysis of radiological findings as well as explant analysis are needed to obtain a more sensitive and specific analysis of the prevalence and incidence of vascular graft calcification and the impact of calcification on synthetic graft outcomes.

Multiple metrics assessment method for a reliable evaluation of corneal suturing skills.

This study aimed to evaluate the efficiency of a multiple metrics assessment method to differentiate between surgeons of differing experience while performing a corneal suturing task. Volunteer ophthalmologists were assigned to three groups (senior [SG], junior [JG] and novice [NG]) according to their experience in corneal suturing. All participants performed three sessions of corneal wound closure by three stitches. Suturing and participant posture were recorded with cameras, and assessed by two blind assessors for stitch quality (using Zhang score) and ergonomics (using Rapid Upper Limb Assessment [RULA] score). Task duration was recorded. Objective analyses of stitches geometry and instrument position were carried out. We included 24 participants: 5 in the SG, 8 in the JG and 11 in the NG. Stitch quality was significantly better and time to perform the procedure significantly lower in more experienced groups (p < 0.001 and p = 0.002, respectively). SG participants better respected regular distance and parallelism between stitches compared to others (p = 0.01). Instrument position was similar between groups, although SG participants minimized their back-and-forth movements compared to NG participants. Ergonomics assessment was similar. Multiple metrics assessment efficiently determined how to differentiate between novices and experienced surgeons on corneal suturing skills, providing hints for future training studies.

Technological Pathways to Produce Compressed and Highly Pure Hydrogen from Solar Power.

Hydrogen (H2 ) produced from renewables will have a growing impact on the global energy dynamics towards sustainable and carbon-neutral standards. The share of green H2 is still too low to meet the net-zero target, while the demand for high-quality hydrogen continues to rise. These factors amplify the need for economically viable H2 generation technologies. The present article aims at evaluating the existing technologies for high-quality H2 production based on solar energy. Technologies such as water electrolysis, photoelectrochemical and solar thermochemical water splitting, liquid metal reactors and plasma conversion utilize solar power directly or indirectly (as carbon-neutral electrons) and are reviewed from the perspective of their current development level, technical limitations and future potential.

Objective Evaluation of Clock Face Suture Using the Objective Structured Assessment of Technical Skill (OSATS) Checklist.

Objective: Assessment of the quality of the final product (QFP) is critical in simulation training, such as the clock face suture (CFS) exercise that is used to assess trainees' needle handling and suturing accuracy. Objective Structured Assessment of Technical Skill (OSATS) scores are the gold standard for the evaluation of trainees. The aim was to investigate variability in the use of OSATS checklists and to evaluate a semi-automatic method of suture analysis vs. OSATS scores. Methods: Details of 287 CFSs performed by trainees during Fundamentals in Vascular Surgery examinations were collected. All were rated according to a seven item OSATS checklist, including QFP score and an overall score by one or two expert surgeons immediately after completion. Interassessor variability was assessed for the CFS that were assessed by two assessors.In order to assess intra- and interassessor variability, 50 CFS pictures were chosen randomly and submitted to three expert surgeons to rate the QFP twice and to carry out a semi-automatic image analysis of each CFS and the estimated cumulative error (CE; mm) recorded. It was hypothesised that the CE correlates to OSATS checklist items or overall score. Variables were compared for correlation with OSATS results using a linear regression. A Pearson's test was used to confirm the proposed hypothesis. Results: Mean ± standard deviation overall score for the OSATS checklist was 20.61 ± 6.33. Inter- and intra-assessor correlation were statistically significant regarding OSATS checklist items. Both correlations presented a low coefficient of determination, indicating variability. The mean CE was 16.07 ± 4.84 mm, and the correlation between the QFP and CE was statistically significant, proving that CE is an objective metric by which to assess the QFP. Conclusion: OSATS score demonstrated intra- and interassessor variability, although there was a significant correlation between scores. CE is an objective metric that is not subject to assessor subjectivity or interassessor variability and is correlated with the gold standard of evaluation.

Xray Exposure Time in Dedicated Academic Simulation Programs Is Realistic of Patient Procedures.

OBJECTIVE: To ascertain whether simulated endovascular procedures are comparable to real life operating room (OR) procedures, particularly with regard to irradiation time. METHODS: This was a retrospective study comparing simulation with clinical data. Fluoroscopy time and overall operation time were compared between simulated abdominal aortic endovascular repair (EVAR) and iliac procedures that were performed, respectively, from 2016 to 2019 and from 2015 to 2019, and clinical EVAR and iliac procedures performed in the OR between January 2018 and November 2021. RESULTS: Within the defined periods, 171 simulated procedures (91 EVAR, 80 iliac) and 199 clinical procedures (111 EVAR, 88 iliac) were performed. For both EVAR and iliac procedures, median total procedure time was much longer during real surgery (p < .001). However, median total fluoroscopy time remained the same, whether the procedure was real surgery or performed on the simulator, for iliac procedures (8.47 minutes in the OR, 8.35 minutes on the simulator, p = .61) and for EVAR procedures (14.80 minutes in the OR, 15.00 minutes on the simulator p = .474). CONCLUSION: Simulated endovascular procedures are comparable with real life OR procedures, particularly with regard to irradiation time when integrated in a dedicated curriculum.

Resident Skills Assessment in Corneal Suturing: A Comprehensive Review of Currently Proposed Educational Programs and Evaluation Tools.

Purpose This study aimed to perform a comprehensive review of publications proposing educational programs for resident skills assessment in corneal suturing. Methods An extensive online article search in PubMed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PISMA) reporting guidelines was performed to identify prospective comparative studies or prospective before/after studies published up to March 2021 and reporting the assessment of ophthalmology residents' skills in corneal suturing during dedicated training sessions. Results Three studies were identified for review. The first reported the efficiency of an electromagnetic tracking system placed on the surgeon's fingers coupled with a computer analysis of movements and time to identify surgeons with different backgrounds in corneal suturing. The second reported the efficiency of the reference system in assessing the improvement of corneal suturing conducted by residents after a training session, with video-based assessment for economy and confidence of movement, limiting tissue damage and precision of operative technique, reviewed by blind assessors. The third proposed an innovative remote corneal suturing training method using Zoom for direct feedback to the residents. The stitch quality was assessed for length, depth, radiality, and tension. The results were similar when compared with a group of residents without feedback. Conclusion This review underlines the rarity and disparity of available tools for corneal suturing assessment, justifying the need for more complete models to be designed. These should consider body ergonomics and stitch quality and time. Comparative studies involving novices and attendings may provide reliable evaluation of existing gaps and specific metrics to target, helping residents to approach their superiors' experience.

Comparing a Neutropenic Diet to a Food Safety-Based Diet in Pediatric Patients Undergoing Hematopoietic Stem Cell Transplantation.

Neutropenic diets were adopted as a way to decrease the infection risks in immunocompromised individuals, but these diets result in significant restrictions in the variety and types of foods an individual may consume. We used a controlled before-and-after study design in consecutive pediatric and young adult patients who underwent hematopoietic stem cell transplant at our center between January 1, 2014, and December 31, 2014. From January through June, all patients were placed on a traditional neutropenic diet; on July 1, we liberalized the bone marrow transplant (BMT) diet to a modified BMT diet. We compared the incidence of bloodstream infections in the first 100 days post-transplant, incidence of norovirus in the first 100 days, total parenteral nutrition days through day 100, incidence of grade 3 to 4 graft-versus-host disease at day 100, gastrointestinal graft-versus-host disease (any stage), and 100-day overall survival. In addition, we administered an investigator-created survey to evaluate food cravings, nausea, diet limitations, and subjective quality of life. In total, 102 patients underwent hematopoietic stem cell transplant during the study period. Forty-nine (48%) received the neutropenic diet and 53 (52%) the BMT diet. Other than more males receiving the neutropenic diet (67% versus 47%, P = 0.05), there were no statistical demographic and outcome differences between the 2 groups. Additionally, 46 subjects (45%) completed the investigator-created questionnaire. There was no difference in the perceived food cravings, nausea, diet limitations, and subjective quality of life between the 2 cohorts. These data demonstrate noninferiority of the modified BMT diet over the traditional neutropenic diet. We believe the food safety-based diet offers a greater variety of food, which may assist in the transition to a normal diet.

An isolated perfused pig heart model for the development, validation and translation of novel cardiovascular magnetic resonance techniques.

BACKGROUND: Novel cardiovascular magnetic resonance (CMR) techniques and imaging biomarkers are often validated in small animal models or empirically in patients. Direct translation of small animal CMR protocols to humans is rarely possible, while validation in humans is often difficult, slow and occasionally not possible due to ethical considerations. The aim of this study is to overcome these limitations by introducing an MR-compatible, free beating, blood-perfused, isolated pig heart model for the development of novel CMR methodology. METHODS: 6 hearts were perfused outside of the MR environment to establish preparation stability. Coronary perfusion pressure (CPP), coronary blood flow (CBF), left ventricular pressure (LVP), arterial blood gas and electrolyte composition were monitored over 4 hours. Further hearts were perfused within 3T (n = 3) and 1.5T (n = 3) clinical MR scanners, and characterised using functional (CINE), perfusion and late gadolinium enhancement (LGE) imaging. Perfusion imaging was performed globally and selectively for the right (RCA) and left coronary artery (LCA). In one heart the RCA perfusion territory was determined and compared to infarct size after coronary occlusion. RESULTS: All physiological parameters measured remained stable and within normal ranges. The model proved amenable to CMR at both field strengths using typical clinical acquisitions. There was good agreement between the RCA perfusion territory measured by selective first pass perfusion and LGE after coronary occlusion (37% versus 36% of the LV respectively). CONCLUSIONS: This flexible model allows imaging of cardiac function in a controllable, beating, human-sized heart using clinical MR systems. It should aid further development, validation and clinical translation of novel CMR methodologies, and imaging sequences.

A protein interaction node at the neurotransmitter release site: domains of Aczonin/Piccolo, Bassoon, CAST, and rim converge on the N-terminal domain of Munc13-1.

Multidomain scaffolding proteins organize the molecular machinery of neurotransmitter vesicle dynamics during synaptogenesis and synaptic activity. We find that domains of five active zone proteins converge on an interaction node that centers on the N-terminal region of Munc13-1 and includes the zinc-finger domain of Rim1, the C-terminal region of Bassoon, a segment of CAST1/ELKS2, and the third coiled-coil domain (CC3) of either Aczonin/Piccolo or Bassoon. This multidomain complex may constitute a center for the physical and functional integration of the protein machinery at the active zone. An additional connection between Aczonin and Bassoon is mediated by the second coiled-coil domain of Aczonin. Recombinant Aczonin-CC3, expressed in cultured neurons as a green fluorescent protein fusion protein, is targeted to synapses and suppresses vesicle turnover, suggesting involvements in synaptic assembly as well as activity. Our findings show that Aczonin, Bassoon, CAST1, Munc13, and Rim are closely and multiply interconnected, they indicate that Aczonin-CC3 can actively participate in neurotransmitter vesicle dynamics, and they highlight the N-terminal region of Munc13-1 as a hub of protein interactions by adding three new binding partners to its mechanistic potential in the control of synaptic vesicle priming.