Vessel ligation training via an adaptive simulation curriculum

Simulation for technical skill acquisition in open vascular surgery

BACKGROUND

Simulation has an increasingly prominent role in modern vascular surgery training. However, it is important to understand how simulation is most effectively delivered to best use the time and resources available. The aim of this narrative review is therefore to critically appraise open technical skill acquisition in the operating room environment and provide recommendations for the future development of evidence-based simulation for open vascular surgery.

METHODS

A systematic search strategy was used to retrieve relevant studies from PubMed, Medline, Web of Science, EMBASE, and the Cochrane databases in July 2019. Included papers were independently screened by two reviewers. Data were subsequently extracted using a standardized proforma and thematically analyzed.

RESULTS

Thirteen studies were included. All demonstrated that simulation is effective in improving confidence and/or competence in performing open technical skills when assessed by previously validated metrics. However, not all participants or course schedules achieved equal benefit, with distributed practice for junior trainees over several weeks achieving a greater improvement in technical skill compared with senior trainees or longer course schedules for some tasks.

CONCLUSIONS

Simulation can be an effective adjunct to traditional operative experience for technical skill acquisition in open vascular surgery. Future work should focus on developing models to address a wider range of training needs, as well as further defining the optimum schedule for the style, content, and timing of simulation for specific learner groups.

Comparison of knot-tying proficiency and knot characteristics for square and reversing half hitch alternating-post surgical knots in a simulated deep body cavity among notice medical students

BACKGROUND

Proficiency-based knot-tying curricula have been developed for square knots for medical students, but, to our knowledge, no such curriculum exists for the reverse half hitch alternating-post (RHAP) knot. We aimed to compare medical students' knot-tying proficiency, knot-tying self-confidence and final knot characteristics for RHAP and square knots in a simulated deep body cavity.

METHODS

We performed a within-subject prospective crossover study of novice medical students who received 30 minutes of training in tying both RHAP and square knots. Participant performance was assessed via a knot-tying checklist, and knot configuration, tensile strength, tightness (loop circumference) and mechanism of failure were also assessed. Participants' self-reported confidence in knot tying was captured.

RESULTS

Twenty-one students participated in the study. Mean scores on the knot-tying checklist were significantly higher for RHAP knots than for square knots (6.9 [standard deviation (SD) 2.1] v. 5.2 [SD 2.3], p < 0.01), and RHAP knots were significantly tighter than square knots (46.8 mm [SD 0.4 mm] v. 49.3 mm [SD 0.7 mm], p < 0.05). There were no differences between RHAP and square knots in correct knot configuration, breaking strength or mechanism of failure. Reverse half hitch alternating-post knots were easier to tie within a deep-body cavity, whereas square knots were easier to learn.

CONCLUSION

Novice medical students were more proficient in tying RHAP knots than square knots in a simulated deep body cavity. Students were able to construct RHAP knots more securely and reported increased confidence in tying RHAP knots at depth compared to square knots.

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.

Declining Operative Experience for Junior-Level Residents: Is This an Unintended Consequence of Minimally Invasive Surgery?

INTRODUCTION

Our group has previously demonstrated an upward shift from junior to senior resident participation in common general surgery operations, traditionally performed by junior-level residents. The objective of this study was to evaluate if this trend would correct over time. We hypothesized that junior resident case volume would improve.

METHODS

A sample of essential laparoscopic and open general surgery procedures (appendectomy, inguinal herniorrhaphy, cholecystectomy, and partial colectomy) was chosen for analysis. The American College of Surgeons National Surgical Quality Improvement Program Participant Use Files were queried for these procedures between 2005 and 2012. Cases were stratified by participating resident post-graduate year with "junior resident" defined as post-graduate year1-3. Logistic regression was performed to determine change in junior resident participation for each type of procedure over time.

RESULTS

A total of 185,335 cases were included in the study. For 3 of the operations we considered, the prevalence of laparoscopic surgery increased from 2005-2012 (all p < 0.001). Cholecystectomy was an exception, which showed an unchanged proportion of cases performed laparoscopically across the study period (p = 0.119). Junior resident participation decreased by 4.5%/y (p < 0.001) for laparoscopic procedures and by 6.2%/y (p < 0.001) for open procedures. The proportion of laparoscopic surgeries performed by junior-level residents decreased for appendectomy by 2.6%/y (p < 0.001) and cholecystectomy by 6.1%/y (p < 0.001), whereas it was unchanged for inguinal herniorrhaphy (p = 0.75) and increased for partial colectomy by 3.9%/y (p = 0.003). A decline in junior resident participation was seen for all open surgeries, with appendectomy decreasing by 9.4%/y (p < 0.001), cholecystectomy by 4.1%/y (p < 0.002), inguinal herniorrhaphy by 10%/y (p < 0.001) and partial colectomy by 2.9%/y (p < 0.004).

CONCLUSIONS

Along with the proliferation of laparoscopy for common general surgical procedures there has been a concomitant reduction in the participation of junior-level residents. As previously thought, familiarity with laparoscopy has not translated to redistribution of basic operations from senior to junior residents. This trend has significant implications for general surgery resident education.

Cumulative sum: An individualized proficiency metric for laparoscopic fundamentals

BACKGROUND

A reliable metric of technical proficiency is indispensable to the training of fellows and residents. The purpose of this study was to determine whether cumulative sum (Cusum) has predictive validity in laparoscopic training. We hypothesized that Cusum would be a better predictor of technical ability in fundamentals of laparoscopic surgery (FLS) than traditional practice volume metrics.

METHODS

Twenty medical students were recruited to practice three FLS tasks: peg transfer, circle cut, and intracorporeal knot tie. Up to 7hours of self-directed practice was allotted to each participant. Practice attempts were scored by standard FLS criteria and monitored via Cusum. Each participant's terminal Cusum performance was analyzed retrospectively. Posttests were conducted by faculty blinded to practice performance.

RESULTS

Eighteen participants completed the study (90%). Median adjusted posttest scores were 102.3, 84.1, and 78.6 for peg transfer, circle cut, and knot tie, respectively. For the knot tie task, participants who exceeded the Cusum decision interval during their final practice attempts performed significantly higher on posttesting (81.2 vs 71.5, p=0.015). Knot tie terminal Cusum score was positively associated with posttest performance after adjusting for practice volume (p=0.031). Total practice volume and practice time were not significantly associated with posttest performance for any FLS task.

CONCLUSION

Cusum score is a more valid representation of FLS proficiency than practice volume or practice time. Incorporating Cusum in a clinical setting may promote more efficient allocation of time resources and operative volume.