Experienced surgeons versus novice surgery residents: Validating a novel knot tying simulator for vessel ligation.

BACKGROUND: Vessel ligation with a knot is one of the most fundamental tasks surgeons must master. We developed a simulator designed to enable novices to acquire and refine gentle knot tying capabilities. METHODS: A bench-top, knot-tying simulator with computer-acquired assessment was tested on expert surgeons and surgery residents at an academic medical center during the years 2016 to 2018. Each participant tied a total of 8 knots in different settings (superficial versus deep) and techniques (1-handed versus 2 hands). The simulator measured vertical forces and task completion time. RESULTS: Fifteen experienced surgeons and 30 surgery residents were recruited. The expert group exerted considerably less total force during placement of the knots than the novice residents (3.8 ± 2.0 vs 9.2 ± 6.1 N, respectively; P = .0005) and the peak force exerted upward was less in the expert group (1.31 ± 0.6 vs 1.75 ± 0.84 N; P = .02). The experts also completed the task in less time (10.9 ± 3.4 vs 18.3 ± 7.2 seconds; P = 0.001). CONCLUSION: The simulator can offer residency programs a low-cost, bench-top platform to train and assess objectively the knot-tying capabilities of surgery residents.

Feedback based simulator training reduces superfluous forces exerted by novice residents practicing knot tying for vessel ligation.

BACKGROUND: Technological advances have led to the development of state-of-the-art simulators for training surgeons; few train basic surgical skills, such as vessel ligation. METHODS: A novel low-cost bench-top simulator with auditory and visual feedback that measures forces exerted during knot tying was tested on 14 surgical residents. Pre- and post-training values for total force exerted during knot tying, maximum pulling and pushing forces and completion time were compared. RESULTS: Mean time to reach proficiency during training was 11:26 min, with a mean of 15 consecutive knots. Mean total applied force for each knot were 35% lower post-training than pre-training (7.5 vs. 11.54 N (N), respectively, p = 0.039). Mean upward peak force was significantly lower after, compared to before, training (1.29 vs. 2.12 N, respectively, p = 0.004). CONCLUSIONS: Simulator training with visual and auditory force feedback improves knot-tying skills of novice surgeons.

Vascular training does matter in the outcomes of saphenous high ligation and stripping.

OBJECTIVE: Varicose vein (VV) surgery is frequently performed by surgeons without formal vascular training. We aimed to compare the outcomes of the procedure based on the background of the surgeon. METHODS: All patients registered with VV surgery between 2004 and 2016 in Portuguese public hospitals were included in the study. Intrahospital outcomes were assessed from this administrative database. A random multicenter sample of 315 patients submitted to saphenous high ligation and stripping (175 patients from six vascular surgery departments and 140 patients from five general surgery divisions) were further queried over the phone, whereby additional nonregistered outcomes were evaluated: preoperative venous ultrasound, impact on quality of life by the 14-item Chronic Venous Insufficiency Quality of Life Questionnaire, visual analogue scale evaluation (score of 1 to 5) of the aesthetic results and general satisfaction, work absence days, and time to return to physical activities. RESULTS: In 13 years, there were 153,382 patients submitted to VV surgery. Of these, 49% were operated on by general surgeons and 40% by vascular surgeons; in 11%, it was not possible to identify the specialty performing the operation. Twenty-three deaths were registered (no differences between groups). In the general surgery group, 14% of patients were hospitalized for more than one night compared with 3% in the vascular group (P < .001). Reintervention rate during the period analyzed was significantly higher in the general surgery group (13.5% vs 8.2%; P < .001). Rate of outpatient surgery was higher in the vascular surgery group (60% vs 36%; P < .001). Phone query revealed similar overall satisfaction and improvement in quality of life in both groups (4.2 vs 4.0 [P = .275] and 35% vs 36% [P = .745], respectively). However, patients operated on by general surgeons reported worse surgical scars (2.8 vs 2.1; P = .007), higher number of residual VVs (2.4 vs 1.7; P = .006), and higher number of days absent from work (40 vs 27 days; P = .005) and took longer to resume physical activities (60 vs 41 days; P = .001). CONCLUSIONS: Despite that the majority of VV surgery in Portugal is executed by general surgeons, this study highlights important advantages when it is performed by surgeons with vascular training.

Endoscopic Sphenopalatine Artery Ligation: General Applicability in a Teaching Unit.

BACKGROUND:: Endoscopic sphenopalatine artery ligation (ESPAL) is the intervention of choice for refractory epistaxis in specialist ear, nose and throat (ENT)units and should be within the repertoire of competencies for all ENT trainees. Following its recent incorporation within the United Kingdom competency-based training syllabus as an explicit outcome standard, the ESPAL is not uncommonly being delivered by trainees under appropriate supervision. We assessed the efficacy and outcome of ESPAL in epistaxis management within our teaching hospitals. METHODS:: Retrospective, structured review of all ESPAL procedures performed for epistaxis between December 2005 and December 2013. The techniques of ligation, operator grade, and outcome were studied. RESULTS:: Sixty-five patients (41 male:24 female; average age of 58.2 years) were identified in whom 67 artery ligations were performed (63 unilateral; 2 bilateral). Overall, success rate of ESPAL was 92.3% (60/65), with 5 rebleed cases recorded within 30 days of the primary procedure. Sixteen (24.6%) underwent "clipping," 26 (40.0%) had diathermy ligation, 18 (27.7%) had both clipping and diathermy, and in 5 (7.7%) patients, the ligation technique was not recorded. In 31 (47.7%) of 65 cases, a consultant was the principal surgeon. The remaining 34 (52.3%) of 65 cases were performed by trainees with (24, 70.6%) or without (10, 29.4%) supervision. There was no correlation between rebleed and operators' grade, level of supervision, or ligation technique. CONCLUSION:: With appropriate training, ESPAL can achieve hemostasis in teams of varying grades of operators without significant reduction in outcome. To further enhance the technical learning curve, the utility of simulation-based training could offer continuous and longitudinal development of skills.

Is Speed a Desirable Difficulty for Learning Procedures? An Initial Exploration of the Effects of Chronometric Pressure.

PURPOSE: To determine whether "chronometric pressure" (i.e., a verbal prompt to increase speed) could predictably alter medical learners' speed-accuracy trade-off during a simulated surgical task, thus modifying the challenge. METHOD: The authors performed a single-task, interrupted time-series study, enrolling surgery residents and medical students from two institutions in September and October 2015. Participants completed 10 repetitions of a simulated blood vessel ligation (placement of two ligatures 1 cm apart). Between repetitions 5 and 6, participants were verbally encouraged to complete the next repetition 20% faster than the previous one. Outcomes included time and accuracy (ligature tightness, placement distance). Data were analyzed using random-coefficients spline models. RESULTS: The authors analyzed data from 78 participants (25 medical students, 16 first-year residents, 37 senior [second-year or higher] residents). Overall, time decreased from the 1st (mean [standard deviation] 39.8 seconds [18.4]) to the 10th (29.6 [12.5]) repetition. The spline model showed a decrease in time between repetitions 5 and 6 of 8.6 seconds (95% confidence interval: -11.1, -6.1). The faster time corresponded with declines in ligature tightness (unadjusted difference -19%; decrease in odds 0.86 [0.76, 0.98]) and placement accuracy (unadjusted difference -5%; decrease in odds 0.86 [0.75, 0.99]). Significant differences in the speed-accuracy trade-off were seen by training level, with senior residents demonstrating the greatest decline in accuracy as speed increased. CONCLUSIONS: Chronometric pressure influenced the speed-accuracy trade-off and modified the challenge level in a simulated surgical task. It may help unmask correctable deficiencies or false plateaus in learners' skill development.

The effect of a multidisciplinary regional educational programme on the quality of colon cancer resection.

AIM: Mesocolic plane surgery with central vascular ligation produces an oncologically superior specimen following colon cancer resection and appears to be related to optimal outcomes. We aimed to assess whether a regional educational programme in optimal mesocolic surgery led to an improvement in the quality of specimens. METHOD: Following an educational programme in the Capital and Zealand areas of Denmark, 686 cases of primary colon cancer resected across six hospitals were assessed by grading the plane of surgery and undertaking tissue morphometry. These were compared to 263 specimens resected prior to the educational programme. RESULTS: Across the region, the mesocolic plane rate improved from 58% to 77% (P < 0.001). One hospital had previously implemented optimal surgery as standard prior to the educational programme and continued to produce a high rate of mesocolic plane specimens (68%) with a greater distance between the tumour and the high tie (median for all fresh cases: 113 vs 82 mm) and lymph node yield (33 vs 18) compared to the other hospitals. Three of the other hospitals showed a significant improvement in the plane of surgical resection. CONCLUSION: A multidisciplinary regional educational programme in optimal mesocolic surgery improved the oncological quality of colon cancer specimens as assessed by mesocolic planes; however, there was no significant effect on the amount of tissue resected centrally. Surgeons who attempt central vascular ligation continue to produce more radical specimens suggesting that such educational programmes alone are not sufficient to increase the amount of tissue resected around the tumour.

Vessel Ligation Fundamentals: A Comparison of Technical Evaluations by Crowdsourced Nonclinical Personnel and Surgical Faculty.

BACKGROUND: Evaluation of fundamental surgical skills is invaluable to the training of medical students and junior residents. This study assessed the effectiveness of crowdsourcing nonmedical personnel to evaluate technical proficiency at simulated vessel ligation. STUDY DESIGN: Fifteen videos were captured of participants performing vessel ligation using a low-fidelity model (5 attending surgeons and 5 medical students before and after training). These videos were evaluated by nonmedical personnel recruited through Amazon Mechanical Turk, as well as by 3 experienced surgical faculty. Evaluation criteria were based on Objective Structured Assessment of Technical Skills (scale: 5-25). Results were compared using Wilcoxon signed rank-sum and Cronbach's alpha (α). RESULTS: Thirty-two crowd workers evaluated all 15 videos. Crowd workers scored attending surgeon videos significantly higher than pretraining medical student videos (20.5 vs 14.9, p < 0.001), demonstrating construct validity. Across all videos, crowd evaluations were more lenient than expert evaluations (19.1 vs 14.5, p < 0.001). However, average volunteer evaluations correlated more strongly with average expert evaluations (α = 0.95) than the strength of correlation between any 2 individual expert evaluators (α = 0.72-0.88). Combined reimbursement for all workers was $80.00. CONCLUSION: After adjustments for score inflation, crowdsourced can evaluate surgical fundamentals with excellent validity. This resource is considerably less costly and potentially more reliable than individual expert evaluations.

Force feedback vessel ligation simulator in knot-tying proficiency training.

BACKGROUND: Tying gentle secure knots is an important skill. We have developed a force feedback simulator that measures force exerted during knot tying. This pilot study examines the benefits of this simulator in a deliberate practice curriculum. METHODS: The simulator consists of silastic tubing with a force sensor. Knot quality was assessed using digital caliper measurement. Participants performed 10 vessel ligations as a pretest, then were shown force readings and tied knots until reaching proficiency targets. Average peak forces precurriculum and postcurriculum were compared using Student t test. RESULTS: Participants exerted significantly less force after completing the curriculum (.61 N ± .22 vs 1.42 N ± .53, P < .001), and had fewer air knots (10% vs 27%). The curriculum was completed in an average of 19.4 ± 6.27 minutes and required an average of 11.7 ± 4.03 knots to reach proficiency. CONCLUSIONS: This study demonstrates the feasibility of real-time feedback in learning to tie delicate knots. The curriculum can be completed in a reasonable amount of time, and may also work as a warm-up exercise before a surgical case.

Design of vessel ligation simulator for deliberate practice.

BACKGROUND: Surgical residents develop technical skills at variable rates, often based on random chance of cases encountered. One such skill is tying secure knots without exerting excessive force. This study describes the design of a simulator using a force sensor to measure instantaneous forces exerted on a blood vessel analog during vessel ligation and the development of expert-derived performance goals. MATERIALS AND METHODS: Vessel ligations were performed on Silastic tubing at an offset from a Vernier Force Sensor. Nine experts (surgical faculty and senior residents) and 10 novices (junior residents) were recruited to each perform 10 vessel ligations (two square knots each) with two-handed and one-handed techniques. Internal consistency for the series of vessel ligations was tested with Cronbach alpha. Maximum forces exerted by novices and experts were compared using Student t-test. RESULTS: Internal consistency across the 10 ligations on the simulator was excellent (Cronbach alpha = 0.91). The expert group on average exerted a significantly lower maximum force when compared with novices while performing two-handed (0.76 ± 0.39 N versus 1.12 ± 0.49 N, P < 0.01) and one-handed (0.84 ± 0.32 N versus 1.36 ± 0.44 N, P < 0.01) vessel ligations. CONCLUSIONS: Although the expert group performed vessel ligations with significantly lower peak force than the novice group, there were novices who performed at the expert level. This is consistent with the conceptual framework of milestones and suggests that the skill of gentle knot-tying can be measured and develops at different chronologic levels of training in different individuals. This simulator can be used as part of a deliberate practice curriculum with instantaneous visual feedback.

Objective assessment of the suture ligature method for the laparoscopic intestinal anastomosis model using a new computerized system.

BACKGROUND: The purpose of this study was to develop a new objective assessment system for the suture ligature method employed in the laparoscopic intestinal anastomosis model. Suturing skills were evaluated objectively using this system. METHODS: This study compared 17 expert surgeons, each of whom had performed >500 laparoscopic procedures, with 36 novice surgeons, each of whom had performed <15 laparoscopic procedures. Each examinee performed a specific skill assessment task using an artificial model that mimics living tissue, which is linked with the Suture Simulator Instruction Evaluation Unit. The model used internal air pressure measurements and image processing to evaluate suturing skills. Five criteria were used to evaluate the skills of participants. RESULTS: The volumes of air pressure leak in the expert and novice groups were 21.13 ± 6.68 and 8.51 ± 8.60 kPa, respectively. The numbers of full-thickness sutures in the expert and novice groups were 2.94 ± 0.24 pairs and 2.47 ± 0.77 pairs, respectively. Suture tensions in the expert and novice groups were 60.99 ± 11.81 and 80.90 ± 16.63 %, respectively. The areas of wound-opening in the expert and novice groups were 1.76 ± 2.17 and 11.06 ± 15.37 mm(2), respectively. The performance times in the expert and novice groups were 349 ± 120 and 750 ± 269 s, respectively. Significant differences between the expert and novice groups for each criterion were observed. The acceptable range of values for each criterion except for the number of full-thickness sutures was statistically defined by the performance of the expert group. CONCLUSIONS: Our system is useful for the quantitative assessment of suturing skill in laparoscopic surgery. We believe that this system is a useful tool for training and assessment of laparoscopic surgeons.

Preliminary evaluation of the pattern cutting and the ligating loop virtual laparoscopic trainers.

INTRODUCTION: The Fundamentals of Laparoscopic Surgery (FLS) trainer is currently the standard for training and evaluating basic laparoscopic skills. However, its manual scoring system is time-consuming and subjective. The Virtual Basic Laparoscopic Skill Trainer (VBLaST©) is the virtual version of the FLS trainer which allows automatic and real time assessment of skill performance, as well as force feedback. In this study, the VBLaST© pattern cutting (VBLaST-PC©) and ligating loop (VBLaST-LL©) tasks were evaluated as part of a validation study. We hypothesized that performance would be similar on the FLS and VBLaST© trainers, and that subjects with more experience would perform better than those with less experience on both trainers. METHODS: Fifty-five subjects with varying surgical experience were recruited at the Learning Center during the 2013 SAGES annual meeting and were divided into two groups: experts (PGY 5, surgical fellows and surgical attendings) and novices (PGY 1-4). They were asked to perform the PC or the ligating loop task on the FLS and the VBLaST© trainers. Their performance scores for each trainer were calculated and compared. RESULTS: There were no significant differences between the FLS and VBLaST© scores for either the PC or the ligating loop task. Experts' scores were significantly higher than the scores for novices on both trainers. CONCLUSION: This study showed that the subjects' performance on the VBLaST© trainer was similar to the FLS performance for both tasks. Both the VBLaST-PC© and the VBLaST-LL© tasks permitted discrimination between the novice and expert groups. Although concurrent and discriminant validity has been established, further studies to establish convergent and predictive validity are needed. Once validated as a training system for laparoscopic skills, the system is expected to overcome the current limitations of the FLS trainer.

Outcomes following neonatal patent ductus arteriosus ligation done by pediatric surgeons: a retrospective cohort analysis.

PURPOSE: Patent Ductus Arteriosus (PDA) ligation in premature infants is an urgent procedure performed by some but not all pediatric surgeons. Proficiency in PDA ligation is not a requirement of Canadian pediatric surgery training. Our purpose was to determine the outcomes of neonatal PDA ligation done by pediatric surgeons. METHODS: We performed a retrospective review of premature infants who underwent PDA ligation by pediatric surgeons in 3 Canadian centers from 2005 to 2009. Outcomes were compared to published controls. RESULTS: The review identified 98 patients with a mean corrected GA and weight at repair of 29 weeks and 1122 g, respectively. There were no intraoperative deaths. The 30-day and inhospital mortality rates were 1% and 5%. Mortality and morbidity were comparable to the published outcomes. CONCLUSIONS: This study documents that a significant number of preterm infant PDA ligations are safely done by pediatric surgeons. To meet the Canadian needs for this service by pediatric surgeons, proficiency in PDA ligation should be considered important in pediatric surgery training programs.

Comparison between the traditional and the new training model using rabbits in the assessment.

PURPOSE: Compare the new training model for vessel ligation with the traditional using rabbits in the assessment. METHODS: From 106 academics of the Division of Operative Technique and Experimental Surgery, 36 were divided into two groups and offered them two training models of ligature. The group was invited to participate to an experimental procedure with rabbits and reproduce the technique trained. The procedure consisted of performing ligatures in saphenous veins of the legs of rabbits. The students were evaluated by objective criteria by an observer evaluator and answered a questionnaire at the end of the procedure. RESULTS: The medical students who have had training with the new model had a higher number of hits compared to the other group performing ligatures without clamping with hemostatic forceps (p<0.05). There was also a higher number of hits for the new model group to perform ligation temporary and permanent ligation with the use of forceps (p>0.05). The questionnaires indicated that the new model develops more ability to work in groups (p=0.088). CONCLUSIONS: The project promotes the implementation of the new model for training ligature, indicating that the new model is better to the traditional surgical practice.

Comparison between the traditional and the new training model using rabbits in the assessment / Comparação entre o tradicional e o novo modelo de treinamento utilizando coelhos para a avaliação

PURPOSE: Compare the new training model for vessel ligation with the traditional using rabbits in the assessment. METHODS: From 106 academics of the Division of Operative Technique and Experimental Surgery, 36 were divided into two groups and offered them two training models of ligature. The group was invited to participate to an experimental procedure with rabbits and reproduce the technique trained. The procedure consisted of performing ligatures in saphenous veins of the legs of rabbits. The students were evaluated by objective criteria by an observer evaluator and answered a questionnaire at the end of the procedure. RESULTS: The medical students who have had training with the new model had a higher number of hits compared to the other group performing ligatures without clamping with hemostatic forceps (p<0.05). There was also a higher number of hits for the new model group to perform ligation temporary and permanent ligation with the use of forceps (p>0.05). The questionnaires indicated that the new model develops more ability to work in groups (p=0.088). CONCLUSIONS: The project promotes the implementation of the new model for training ligature, indicating that the new model is better to the traditional surgical practice.

OBJETIVO: Comparar o novo modelo de treinamento de ligadura de vaso com o tradicional a partir de modelo experimental com coelhos. MÉTODOS: De 106 acadêmicos da Disciplina de Técnica Operatória e Cirurgia Experimental, 36 foram distribuídos em dois grupos e foram ofertados a eles dois modelos de treinamento de ligadura. O grupo foi convidado a participar de procedimento experimental com coelhos para a reprodução da técnica treinada. O procedimento consistiu da realização de ligaduras nas veias safenas das coxas dos coelhos. Os acadêmicos foram avaliados por critérios objetivos por avaliador observador e responderam a um questionário ao final procedimento. RESULTADOS: Os acadêmicos que tiveram treinamento com o novo modelo tiveram maior número de acertos quando comparado o outro grupo para realização de ligaduras sem clampeamento com pinças hemostáticas (p<0,05). Houve maior número de acertos para realização de ligadura temporária e de ligadura definitiva com uso de pinças (p>0,05) para o grupo do novo modelo. Os questionários indicaram que o novo modelo desenvolve mais a habilidade de trabalho em grupo (p=0,088). CONCLUSÃO: O projeto favorece a implantação do novo modelo para treinamento de ligaduras, indicando que o novo modelo se aproxima mais com a prática cirúrgica que o tradicional.

[Hypogastric artery ligation. Safety and efficacy of a training program]. / Ligadura de arterias hipogástricas. Seguridad y eficacia de un programa de adiestramiento.

Bilateral hypogastric artery ligation is a technique described in the antiquity to restrain the hemorrhage in the gynecological and obstetric surgery. There are few Gineco-obstetricians that dominate the technique, for what intended a training program, in which was to demonstrate their security and effectiveness. We carry out a program where were qualified 14 gineco-obstetricians, theoretical and surgically. Results were analyzed finding an acceptable security with 1.5% of complications and an effectiveness demonstrated when having to the program 92.9% of students that reached the competition. We intend to reply the course in other hospital units, in order to decrease the maternal mortality for hemorrhage obstetric or gynecological.