Tissue-based coronary surgery simulation: medical student deliberate practice can achieve equivalency to senior surgery residents

Abstract

Objective: The study objective was to assess the impact of dedicated instruction and deliberate practice on fourth-year medical students' proficiency in performing a coronary anastomosis using a porcine heart model, compared with nonsimulator-trained senior general surgery residents.

Methods: Ten fourth-year medical students were trained to perform a coronary anastomosis using the porcine simulator. Students trained for 4 months using deliberate practice methodology and one-on-one instruction. At the end of the training, each student was filmed performing a complete anastomosis. Eleven senior general surgery residents were filmed performing an anastomosis after a single tutorial. All films were graded by 3 independent cardiac surgeons in a blinded fashion. The primary outcome was the median final score (range, 1-10) of a modified Objective Structured Assessment of Technical Skill scale. The secondary outcome was time to completion in seconds. Statistical analysis used both parametric (Student t test) and nonparametric (Wilcoxon rank-sum) methods.

Results: The median combined final score for medical students was 3 (interquartile range, 2.3-4.8), compared with 4 (interquartile range, 3.3-5.3) for residents (P = .102). The overall median individual final scores were 3 (interquartile range, 2-6) for grader 1, 3 (interquartile range, 2-5) for grader 2, and 4 (interquartile range, 3-5) for grader 3. For each individual grader, there was no difference in median final scores between medical students and residents. The mean time to completion was 792.7 seconds (95% confidence interval, 623.4-962) for medical students and 659 seconds (95% confidence interval, 599.1-719) for residents (P = .118).

Conclusions: Dedicated instruction of fourth-year medical students with deliberate and distributed practice of microvascular techniques using a porcine end-to-side coronary artery anastomosis simulation model results in performance comparable to that of senior general surgery residents. These results suggest that focused tissue simulator training can compress the learning curve to acquire technical proficiency in comparison with real-time training.