The Benefits of Expert Instruction in Microsurgery Courses

Rat Microvascular Model is Tolerant to Technical Errors

BACKGROUND

 Extensive studies have been conducted using the rat model to understand the potential technical errors that lead to anastomotic failure. However, current literature indicates that the rat model has excellent tolerance to diverse errors committed by microsurgeons. The error-investigating rat model is often created by one or two experienced surgeons, and only one isolated technical error is examined. These biases may potentially cause limitations of the results from previous studies. Meanwhile, venous anastomoses have rarely been investigated in previous literature. Therefore, it is important to elucidate this topic with a more comprehensive study design.

METHODS

 Ninety-four arterial and 94 venous anastomoses on Sprague-Dawley rat femoral vessels that were performed by 47 microsurgeons who participated in the microsurgery course at the Columbia University and the University of Thessaloniki were evaluated. In total, 10 technical errors were examined: (1) disruption of suture line, (2) back-wall stitch, (3) oblique stitch, (4) wide bite, (5) partial thickness bite, (6) unequal suture distance, (7) tear in vessel wall, (8) excessively tight suture, (9) suture threads in lumen, and (10) large edge overlap. The frequency of each error committed, and the 30-minute postoperative patency was also recorded. The underlying causal relationship between these errors, potential interaction, and the short-term anastomosis patency was analyzed statistically.

RESULTS

 Only the back-wall stitch was found to have a significant causal effect on arterial anastomosis failure (p < 0.001). Back-wall stitch, wide bite, and partial thickness bite significantly impact venous anastomosis patency (p < 0.001). No other statistically significant result was found.

CONCLUSION

 Overall, the rat model is highly resilient to various technical errors despite these mistakes being often considered clinically unacceptable. Therefore, researchers need to consider the resilience of the rat model when designing and analyzing future studies. In addition, microsurgery instructors should focus on individual stitch quality rather than the final patency.

Evaluation of a Microsurgery Training Curriculum

BACKGROUND

 Microsurgery is one of the most challenging areas of surgery with a steep learning curve. To address this educational need, microsurgery curricula have been developed and validated, with the majority focus on technical skills only. The aim of this study was to report on the evaluation of a well-established curriculum using the Kirkpatrick model.

METHODS

 A training curriculum was delivered over 5 days between 2017 and 2020 focusing on (1) microscopic field manipulation, (2) knot tying, nondominant hand usage, (3) 3-D models/anastomosis, and (4) tissue experience. The Kirkpatrick model was applied to evaluate the curriculum at four levels: (1) participants' feedback (2) skills development using a validated, objective assessment tool (Global Assessment Score form) and CUSUM charts were constructed to model proficiency gain (3) and (4) assessing skill retention/long-term impact.

RESULTS

 In total, 155 participants undertook the curriculum, totaling 5,425 hours of training. More than 75% of students reported the course as excellent, with the remaining voting for "good." All participants agreed that the curriculum met expectations and would recommend it. Significant improvement in anastomosis attainment scores between days 1 and 3 (median score 4) and days 4 and 5 (median score 5) (W = 494.5, p = 0.00170). The frequency of errors reduced with successive attempts (chi square = 9.81, p = 0.00174). The steepest learning curve was in anastomosis and patency domains, requiring 11 attempts on average to reach proficiency. In total, 88.5% survey respondents could apply the skills learnt and 76.9% applied the skills learnt within 6 months. Key areas of improvement were identified from this evaluation, and actions to address them were implemented in the following programs.

CONCLUSION

 Robust evaluation of curriculum can be applied to microsurgery training demonstrating its efficacy in reducing surgical errors with an improvement in overall technical skills that can extend to impact clinical practice. It allows the identification of areas of improvement, driving the refinement of training programs.

Validation of a simplified evaluation grid applied to the microsurgery on inert material via smartphone

OBJECTIVES

Microsurgery is usually performed in experimental research models and clinical surgery. It requires meticulous technical skills and continuous training. Inert materials such as Shirataki noodles are readily available and low-cost consumables regularly used for practice. The objective of this study was to evaluate the repeatability and reproducibility of a simplified evaluation grid of suture on inert material (Shirataki Konnyaku noodle) under smartphone magnification.

MATERIAL AND METHODS

Ten students performed end-to-end suture on inert material with magnification via their smartphone. Each suture was filmed, and the videos were randomized. Each student was evaluated on each video three times over three consecutive days, using a simplified evaluation grid. Intra- and inter-observer agreement was evaluated on Concordance Correlation Coefficients. Values were assessed on Pearson's correlation coefficient.

RESULTS

Intra-observer correlation was weak for 2 items (0.288 and 0.246) and moderate for the other 2 (0.419 and 0.529). Inter-observer correlation was weak for 3 items (0.344, 0.358, and 0.276) and close to zero for the other (0.034).

CONCLUSION

This simplified evaluation grid for microsurgery training on inert material via smartphone was poorly repeatable and reproducible. Loss of certain items in the grid due to the use of inert material probably impaired relevance.

Fundamentals of Microsurgery: A Novel Simulation Curriculum Based on Validated Laparoscopic Education Approaches

BACKGROUND

 Microsurgical techniques have a steep learning curve. We adapted validated surgical approaches to develop a novel, competency-based microsurgical simulation curriculum called Fundamentals of Microsurgery (FMS). The purpose of this study is to present our experience with FMS and quantify the effect of the curriculum on resident performance in the operating room.

METHODS

 Trainees underwent the FMS curriculum requiring task progression: (1) rubber band transfer, (2) coupler tine grasping, (3) glove laceration repair, (4) synthetic vessel anastomosis, and (5) vessel anastomosis in a deep cavity. Resident anastomoses were also evaluated in the operative room with the Stanford Microsurgery and Resident Training (SMaRT) tool to evaluate technical performance. The National Aeronautics and Space Administration Task Load Index (NASA-TLX) and Short-Form Spielberger State-Trait Anxiety Inventory (STAI-6) quantified learner anxiety and workload.

RESULTS

 A total of 62 anastomoses were performed by residents in the operating room during patient care. Higher FMS task completion showed an increased mean SMaRT score (p = 0.05), and a lower mean STAI-6 score (performance anxiety) (p = 0.03). Regression analysis demonstrated residents with higher SMaRT score had lower NASA-TLX score (mental workload) (p < 0.01) and STAI-6 scores (p < 0.01).

CONCLUSION

 A novel microsurgical simulation program FMS was implemented. We found progression of trainees through the program translated to better technique (higher SMaRT scores) in the operating room and lower performance anxiety on STAI-6 surveys. This suggests that the FMS curriculum improves proficiency in basic microsurgical skills, reduces trainee mental workload, anxiety, and improves intraoperative clinical proficiency.

Reduction of the Number of Live Animals Used for Microsurgical Skill Acquisition: An Experimental Randomized Noninferiority Trial

BACKGROUND

 Live animals have been used for decades as one of the many training models for developing surgical skills. Microsurgery in particular relies on training for skill acquisition and maintenance, using live animal models, especially rats (murine models). Efforts are underway to reduce the number of rats sacrificed to achieve this objective.

METHODS

 A group of students with minimal microsurgical experience, after having gone through a basic microsurgical course, were randomly split into three equal groups, all three groups following a 24-week standard training program based on low- and medium-fidelity training models with standardized murine training days. In addition to the standard training regimen, each participant performed supplementary training on live rats every 4, 6, or 8 weeks. According to the training program, the procedures have been performed on chicken legs, flower petals, and rats, each procedure being blindly assessed and evaluated using validated models and scales. The primary evaluated outcome was the Stanford Microsurgery and Resident Training (SMaRT) scale result of the final rat anastomosis performed by each group, for which the tested hypothesis was one of noninferiority. The secondary outcomes were represented by the final rat anastomosis time, final chicken leg anastomosis result and time, and the final petal score.

RESULTS

 After the 24th week, no differences were observed between the three groups regarding their microsurgical skills, as measured by the aforementioned surgical outcomes. All participants improved significantly during the study (mean [standard deviation] 19 ± 4 points on the SMaRT scale), with no significant differences between the groups, p < 0.001 for noninferiority.

CONCLUSION

 A training regimen based on low- and moderate-fidelity models, with the addition of training on a live rat every 8 weeks was noninferior to a training regimen that used a live rat every 6 weeks and also noninferior to a training regimen that used a live rat every 4 weeks.

Video-Based Microsurgical Education versus Stationary Basic Microsurgical Course: A Noninferiority Randomized Controlled Study

BACKGROUND

 Repetitive training is essential for microsurgical performance. This study aimed to compare the improvement in basic microsurgical skills using two learning methods: stationary microsurgical course with tutor supervision and self-learning based on digital instructional materials. We hypothesized that video-based training provides noninferior improvement in basic microsurgical skills.

METHODS

 In this prospective study, 80 participants with no prior microsurgical experience were randomly divided into two groups: the control group, trained under the supervision of a microsurgical tutor, and the intervention group, where knowledge was based on commonly available online instructional videos without tutor supervision. Three blinded expert microsurgeons evaluated the improvement in basic microsurgical skills in both groups. The evaluation included an end-to-end anastomosis test using the Ten-Point Microsurgical Anastomosis Rating Scale (MARS10) and a six-stitch test on a latex glove. Statistically significant differences between groups were identified using standard noninferiority analysis, chi-square, and t-tests.

RESULTS

 Seventy-seven participants completed the course. Baseline test scores did not differ significantly between groups. After the 4-day microsurgical course, both groups showed statistically significant improvement in microsurgical skills measured using the MARS10. The performed tests showed that data for self-learning using digital resources provides noninferior data for course with surpervision on the initial stage of microsurgical training (7.84; standard deviation [SD], 1.92; 95% confidence interval [CI], 7.25-8.44) to (7.72; SD, 2.09; 95% CI, 7.07-8.36).

CONCLUSION

 Video-based microsurgical training on its initial step provides noninferior improvement in microsurgical skills to training with a dedicated instructor.

MicrosimUC: Validation of a Low-Cost, Portable, Do-It-Yourself Microsurgery Training Kit

BACKGROUND

 Microsurgery depends largely on simulated training to acquire skills. Courses offered worldwide are usually short and intensive and depend on a physical laboratory. Our objective was to develop and validate a portable, low-cost microsurgery training kit.

METHODS

 We modified a miniature microscope. Twenty general surgery residents were selected and divided into two groups: (1) home-based training with the portable microscope (MicrosimUC, n = 10) and (2) the traditional validated microsurgery course at our laboratory (MicroLab, n = 10). Before the intervention, they were assessed making an end-to-end anastomosis in a chicken wing artery. Then, each member of the MicrosimUC group took a portable kit for remote skill training and completed an eight-session curriculum. The laboratory group was trained at the laboratory. After completion of training, they were all reassessed. Pre- and posttraining procedures were recorded and rated by two blind experts using time, basic, and specific scales. Wilcoxon's and Mann-Whitney tests were used to compare scores. The model was tested by experts (n = 10) and a survey was applied to evaluate face and content validity.

RESULTS

 MicrosimUC residents significantly improved their median performance scores after completion of training (p < 0.05), with no significant differences compared with the MicroLab group. The model was rated very useful for acquiring skills with 100% of experts considering it for training. Each kit had a cost of U.S. $92, excluding shipping expenses.

CONCLUSION

 We developed a low-cost, portable microsurgical training kit and curriculum with significant acquisition of skills in a group of residents, comparable to a formal microsurgery course.

Superiority of living animal models in microsurgical training: beyond technical expertise

Background

Many studies are investigating the role of living and nonliving models to train microsurgeons. There is controversy around which modalities account for the best microsurgical training. In this study, we aim to provide a systematic literature review of the practical modalities in microsurgery training and compare the living and nonliving models, emphasizing the superiority of the former. We introduce the concept of non-technical skill acquisition in microsurgical training with the use of living laboratory animals in the context of a novel proposed curriculum.

Methods

A literature search was conducted on PubMed/Medline and Scopus within the past 11 years based on a combination of the following keywords: “microsurgery,” “training,” “skills,” and “models.” The online screening process was performed by two independent reviewers with the Covidence tool. A total of 101 papers was identified as relevant to our study. The protocol was reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

Results

Living models offer the chance to develop both technical and non-technical competencies (i.e., leadership, situation awareness, decision-making, communication, and teamwork). Prior experience with ex vivo tissues helps residents consolidate basic skills prior to performing more advanced techniques in the living tissues. Trainees reported a higher satisfaction rate with the living models.

Conclusions

The combination of living and nonliving training microsurgical models leads to superior results; however, the gold standard remains the living model. The validity of the hypothesis that living models enhance non-technical skills remains to be confirmed.

Level of evidence: Not ratable.