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Surgical Training Model Is Safe Despite Older Surgical Patients With More Complications

Key findings

  • A surgical resident training model was proven to be safe and adequate, despite older surgical patients with more complications
  • Cardiac surgery outcomes, including reoperation rates, were similar for the surgical attending and residents with the only difference being residents’ longer operation times
  • Nine readmissions within 30 days occurred for the attending, compared to zero readmissions for residents, reflecting a necessary skewed caseload for the attending who took on the most difficult cases to protect patient safety

With the increased frequency of older patients with complications, surgeons can have a built-in disincentive to expose themselves and patients to resident-directed operations at a time when outcomes data is tracked extensively and connected to a surgeon’s and hospital’s names. A tension exists to ensure residents are fully trained on operations, while at the same time patient outcomes are protected.

Massachusetts General Hospital has an apprenticeship model in which a resident works with an attending for a two-to-three-month period. During that time, residents can assume the responsibility of having primary surgical oversight with supervision. With a cardiac surgical landscape more complex than in the past, is this teaching model safe? A first-ever comparative outcomes study led by Cardiac Surgeon George Tolis, MD, and Thoralf Sundt, MD, chief of Cardiac Surgery, finds the surgical teaching model to be safe for preparing surgical residents for cardiac operations.

The Mass General team, reporting in the Journal of Thoracic and Cardiovascular Surgery, compared case-matched (i.e. no significant differences in patient profiles) outcomes from 100 cardiac operations performed by Dr. Tolis and 100 from eight surgical residents from July 2014 to December 2016. Of these cases, most patients had undergone isolated coronary artery bypass grafting (CABG) or isolated aortic valve replacement (AVR).

Residents included in the study showed competency in each separate step of an operation. The study revealed the degree of trainee independence conferred in the past still makes sense. Outcomes from cases performed by Dr. Tolis were similar to those of his residents, even though the latter’s operating times were longer. Given that they were relatively inexperienced and in training, residents mean operative times were 4.6 vs. 2.7 hours (P <.001) for Dr. Tolis. They were also longer specifically for cardiopulmonary bypass (96 vs. 50 minutes, P <.001) and for aortic cross-clamping (78 vs. 39 minutes, P <.001).

There were no in-hospital or 30-day deaths for any patients. Researchers concluded, after controlling for Dr. Tolis’ more complicated caseload, that other outcomes were comparable, such as lengths of stay and rates of red blood cell transfusions, re-explorations, stroke or wound infections.

Due to the need to preserve patient safety at all costs, Dr. Tolis took on the most complex cases that included patients requiring an emergency operation or intra-aortic balloon pump support. Also, nine readmissions within 30 days occurred for the attending compared to zero readmissions for the residents.

Overall, the results bolstered the relevancy of Mass General’s apprenticeship model. The authors noted that the supervision and any training involved that can elongate operative times is a reality that the system does not reimburse for through added payment.

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