Multistate improvement in process and outcomes of carotid endarterectomy.

OBJECTIVES: The purpose of this study was to assess the effect of community-wide performance measurement and feedback on key processes and outcomes of carotid endarterectomy (CEA).
METHODS: Complete medical record (hospital chart) review for indications, care processes, and outcomes was performed on a random sample of Medicare patients undergoing CEA in 10 states (Arkansas, Georgia, Illinois, Indiana, Iowa, Kentucky, Michigan, Nebraska, Ohio, Oklahoma) during baseline (Jun 1, 1995 to May 31, 1996) and remeasurement (Jun 1, 1998 to May 31, 1999) periods. In addition to review of the index hospital stay, hospital admissions within 30 days of the procedure were reviewed and the Medicare enrollment database queried to identify out-of-hospital deaths, to determine 30-day outcome results. The baseline data by state were provided to the Medicare Quality Improvement Organizations (QIOs) in the respective states, and quality improvement initiatives were encouraged.
RESULTS: We reviewed 9945 primary CEA alone procedures, 236 CEA and coronary artery bypass grafting (CABG) procedures, and 380 repeat CEA operations during the baseline period (B), and 9745 primary CEA alone procedures, 233 CEA and CABG procedures, and 401 repeat CEA operations during the remeasurement period (R). There was a significant decrease in the combined event rate (30-day stroke or mortality) for CEA alone procedures between baseline and remeasurement (B, 5.6%; R, 5.0%). A decrease occurred in each of the indication strata; transient ischemic attack or stroke (B, 7.7%; R, 6.9%), nonspecific symptoms (B, 5.9%; R, 5.4%), and no symptoms (B, 4.1%; R, 3.8%). The combined event rate also decreased for CEA and CABG (B, 17.4%; R, 13.3%) and repeat CEA operations (B, 6.8%; R, 5.7%). The remeasurement period state-to-state variation in combined event rate for CEA alone ranged from 2.7% (Georgia) to 5.9% (Indiana) for all indications combined, from 4.4% (Georgia) to 10.9% (Michigan) in patients with recent transient ischemia or stroke, from 1.4% (Georgia) to 6.0% (Oklahoma) in patients with no symptoms, and from 3.7% (Georgia) to 7.9% (Indiana) in patients with nonspecific symptoms. There were significant increases in preoperative antiplatelet administration (62%-67%; P <.0001) and patching (29%-45%; P =.05) from baseline to remeasurement in the CEA alone subset. Preoperative antiplatelet administration and patching were associated with improved outcomes in the combined baseline and remeasurement data.
CONCLUSIONS: Community-wide quality improvement initiatives with performance measurement and confidential reporting of provider level data can lead to improvement in important care processes and outcomes. There is considerable variation between states in outcome and process, and thus continued room for improvement. Quality improvement projects that include standardized confidential outcome reporting should be encouraged. Preoperative antiplatelet therapy administration and patching rates should be considered as evidence-based performance measures.