Surgical Care Improvement Project measure for postoperative glucose control should not be used as a measure of quality after cardiac surgery

Abstract

The current Surgical Care Improvement Project (SCIP) measure for controlled postoperative 6-am glycemic control after cardiac surgery identifies those with blood glucose levels of ≤200 mg/dL. The purpose of the present study was to evaluate the effect of achieving this SCIP measure on risk-adjusted postoperative cardiac surgical outcomes. The data were analyzed for all cardiac surgery patients from a single institution (June 2010 to August 2012). The patients were categorized by the postoperative 6-am glucose levels into 2 SCIP measure cohorts: SCIP (≤200 mg/dL) versus non-SCIP (>200 mg/dL). Propensity-matched cohort comparisons and multiple regression analyses assessed the associations between SCIP measure compliance and the risk-adjusted outcomes. Of 1703 patients, 1527 (90%) achieved SCIP measure glycemic control. Preoperative diabetes was more common among the non-SCIP patients (P<.001); the median Society of Thoracic Surgeons-predicted mortality (P=.14) was similar between the 2 groups. No significant differences were observed in major morbidity, mortality, or resource usage among the propensity-matched cohorts. After adjustment for Society of Thoracic Surgeons-predicted risk, non-SCIP status was not associated with increased mortality (P=.44), composite major morbidity (P=.16), major sternal complications (P=.68), total intensive care unit duration (P=.70), or postoperative length of stay (P=.27). Similar risk-adjusted results were estimated for patients undergoing isolated coronary artery bypass grafting. Achieving the SCIP measure for controlled postoperative 6-am blood glucose levels ≤200 mg/dL after cardiac surgery was not associated with improved risk-adjusted mortality, morbidity, or hospital resource usage. These data suggest that this metric might not be a valid measure of postoperative cardiac surgical quality.