Does the level of experience of residents affect outcomes of coronary artery bypass surgery?

Ann Thorac Surg. 2009 Apr;87(4):1127-33; discussion 1133-4. doi: 10.1016/j.athoracsur.2008.12.080.


Background: At our institution, coronary artery bypass grafting (CABG) operations are performed by staff surgeons or by first- or second-year cardiothoracic residents under the direct supervision of attending surgeons. We evaluated the influence of surgical seniority on outcomes.

Methods: Using prospectively collected data from our departmental database, we identified all primary, isolated CABG operations (n = 1,042) performed between July 1997 and April 2007. Operations were then stratified according to the seniority of the primary surgeon: first-year cardiothoracic resident (CT1), second-year cardiothoracic resident (CT2), or staff surgeon. Data were examined for any association between seniority and surgical outcomes.

Results: Staff, CT2, and CT1 surgeons performed 47 (4%), 610 (59%), and 385 (37%) cases, respectively. Efficiency was correlated with experience: for CT1, CT2, and staff surgeons, respectively, operative times averaged 345, 313, and 302 minutes; perfusion times averaged 118, 106, and 96 minutes; and cross-clamp times averaged 68, 58, and 57 minutes (p < 0.05 for all comparisons). The incidences of major morbidity (10.1%, 12.3%, 12.8%) and operative mortality (0.8%, 1.5%, 2.1%) were similar after operations performed by CT1, CT2, and staff surgeons, respectively (p > 0.15 for all). In univariate and multivariate analyses, the seniority of the primary surgeon did not independently predict morbidity or perioperative mortality. On follow-up (mean, 1,485 +/- 1,015 days), there was no significant difference in patient survival (log-rank, p = 0.64).

Conclusions: Lower academic seniority was associated with longer CABG operative times but did not affect outcomes. Thus, training residents to perform CABG is safe and is characterized by progressive improvement in their technical efficiency.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aged
  • Clinical Competence
  • Coronary Artery Bypass / statistics & numerical data*
  • Efficiency
  • Fellowships and Scholarships*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Time Factors
  • Treatment Outcome