Nobody does it better? The impact of surgeon specialty on outcomes for carotid endarterectomy.
- Presenter:
Chair: Melayne McInnes; Discussant: Melayne McInnes Wed June 7, 2006 9:45-11:15 Room 226
Rationale: Carotid endarterectomy (CEA) is a surgical procedure that is used as a prophylaxis for stroke. It is one of the most frequently performed surgical procedures in the United States. Traditionally, this procedure has been performed by surgeons in at least four specialties: vascular surgery, cardiothoracic surgery, general surgery, and neurosurgery. Although a few studies address the effect of surgeon specialty on outcomes, these studies have focused on inpatient mortality, which is not a common outcome, and no study has examined the impact of surgical specialty on long-term rates of stroke and other cerebrovascular events that the procedure is given to prevent.
Objectives: The purpose of this study was to determine whether surgeon specialty was associated with long-term outcomes of patients undergoing CEA in Pennsylvania.
Methodology: Data were from the Pennsylvania Health Care Cost Containment Council (PHC4) and included 17,635 patients admitted for CEA between 1995 and 1997. Long term outcomes were taken from patient readmission data for the 5-year follow-up period ending in 2002. The primary outcomes studied were mortality, stroke, combined stroke and mortality, transient ischemic attack (TIA), and re-occlusion of the ipsilateral artery. Time to event for these outcomes was modeled using a Cox proportional hazards model. Secondary outcomes included length of stay and total charges. These were modeled using a generalized linear model assuming a gamma family and a log link function.
Results: Using general surgeon as the reference group, and controlling for age, race, severity, and admission type, we found no significant difference across surgical specialties in overall mortality at 5 years after CEA. Patients treated by vascular surgeons were found to have significantly fewer (P=.005) strokes at 5 years than those treated by general surgeons. Patients of cardiothoracic (P=.085) and neurosurgeons (P=.969) did not have significantly fewer strokes than those treated by general surgeons. We found no significant difference across surgeon specialties for combined 5 year stroke and death rate. Patients of vascular surgeons had fewer TIAs than those of general surgeons (P=.041) at 5 years. Patients treated by cardiothoracic (P=.508) and neurosurgeons (P=.890) did not have significantly different 5 year TIA rates from those treated by general surgeons. Finally, patients of vascular surgeons were found to have a significantly lower re-occlusion rate (P=.009) when compared to patients of general surgeons. Patients of cardiothoracic (P=.247) and neurosurgeons (P=.284) did not have a significantly different re-occlusion rate than those treated by general surgeons.
Conclusions: These results suggest that there are significant differences in outcomes for carotid endarterectomy associated with the training of the operating surgeon. One explanation for this is the human capital differences that are fostered by the surgical specialties. There may also be learning-by-doing dimensions as surgeons who perform operations on vessels and on the neck may have an advantage in terms of outcomes.
