How safe is it to train residents to perform off-pump coronary artery bypass surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, in [patients undergoing off-pump CABG] are [postoperative mortality and morbidity outcomes] acceptable when performed by [trainees]? Altogether more than 597 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. Six retrospective cohort studies directly compared the performance of trainees and experienced surgeons in off-pump coronary artery bypass graft surgery. Of the remaining papers, one recorded the performance of trainees in on-and off-pump operations and finally one paper evaluated a single trainee's performance in off-pump coronary artery bypass graft surgery, both supervised and unsupervised, over a 1-year period. It is important to note that the two respective cohort studies included in our analysis compared similar cohorts of patients. However, both studies were included in our paper as they provide additional information regarding trainee performance. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Although a heterogeneous range of postoperative complications were recorded in the identified studies, we were able to determine that, overall, there was no significant difference in the 30-day mortality seen in operations performed by trainees or experienced surgeons. The incidence of myocardial infarction and stroke were also similar among cases performed by both groups. However, senior surgeons were more likely to operate on patients with more complex or severe disease, or those requiring more urgent operations. Therefore, it was not possible to directly compare outcomes between trainees and experienced surgeons in operations of similar complexity. However, we conclude that despite the absence of randomized controlled trials comparing the performance of trainees and experienced surgeons in off-pump coronary artery bypass (OPCAB) surgery, the evidence provided in this paper supports the involvement of trainees in performing off-pump coronary artery bypass graft surgery as a reliable and safe alternative to on-pump coronary artery bypass graft surgery in selected cases.