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

The technique of off-pump coronary artery bypass graft (OPCABG) surgery differs considerably from on-pump CABG. This study investigates the impact of surgical training on clinical outcome in patients undergoing OPCABG.

All 251 OPCABG cases performed by one service over an 18-month period were analyzed. The 83 operations (33%) performed by two trainees under supervision were compared with the 168 operations (67%) performed by an experienced consultant surgeon. Patient and disease characteristics, intraoperative and postoperative data, morbidity and mortality were analyzed using univariate and multivariate analysis. Data were extracted from a prospective database.

Patients operated on by the consultant were more likely to have had unstable angina (p = 0.003, odds ratio [OR] = 3.5), impaired left ventricular function (ejection fraction < 0.3; p = 0.005, OR = 2.4), or previous cardiac surgery (p = 0.03). They were more likely to receive three or more grafts (p = 0.017, OR = 2.0). Operative mortality was 2.4% (consultant) and 0% (trainees; p = 0.31). Postoperative morbidity, such as reoperation for bleeding (consultant 3% versus trainees 1.2%), stroke (0.6% versus 1.2%), and hemofiltration (3.6% versus 0%) was similar between the two patient groups. Stay in the intensive care unit was not significantly different in the two groups.

In our experience, trainee surgeons are less likely to operate on patients with unstable angina or cardiac dysfunction. Operative morbidity and mortality are, however, similar in patients operated on by either an experienced consultant surgeon or trainees. We believe OPCABG can be taught safely to trainees under supervision.