Revised Cardiac Risk Index as a Predictor for Myocardial Infarction and Cardiac Arrest Following Posterior Lumbar Decompression

STUDY DESIGN: A retrospective analysis of prospectively collected data. OBJECTIVE: The aim of this study was to determine the ability of Revised Cardiac Risk Index (RCRI) to predict adverse cardiac events following posterior lumbar decompression (PLD). SUMMARY OF BACKGROUND DATA: PLD is an increasingly common procedure used to treat a variety of degenerative spinal conditions. The RCRI is used to predict risk for cardiac events following noncardiac surgery. There is a paucity of literature that directly addresses the relationship between RCRI and outcomes following PLD, specifically, the discriminative ability of the RCRI to predict adverse postoperative cardiac events. METHODS: ACS-NSQIP was utilized to identify patients undergoing PLD from 2006 to 2014. Fifty-two thousand sixty-six patients met inclusion criteria. Multivariate and ROC analysis was utilized to identify associations between RCRI and postoperative complications. RESULTS: Membership in the RCRI=1 cohort was a predictor for myocardial infarction (MI) [odds ratio (OR) = 3.3, P = 0.002] and cardiac arrest requiring cardiopulmonary resuscitation (CPR) (OR = 3.4, P = 0.013). Membership in the RCRI = 2 cohort was a predictor for MI (OR = 5.9, P = 0.001) and cardiac arrest requiring CPR (OR = 12.5), Membership in the RCRI = 3 cohort was a predictor for MI (OR = 24.9) and cardiac arrest requiring CPR (OR = 26.9, P = 0.006). RCRI had a good discriminative ability to predict both MI [area under the curve (AUC) = 0.876] and cardiac arrest requiring CPR (AUC = 0.855). The RCRI had a better discriminative ability to predict these outcomes that did ASA status, which had discriminative abilities of "fair" (AUC = 0.799) and "poor" (AUC = 0.674), respectively. P < 0.001 unless otherwise specified. CONCLUSION: RCRI was predictive of cardiac events following PLD, and RCRI had a better discriminative ability to predict MI and cardiac arrest requiring CPR than did ASA status. Consideration of the RCRI as a component of preoperative surgical risk stratification can minimize patient morbidity and mortality. Studies such as this can allow for implementation of guidelines that better estimate the preoperative risk profile of surgical patients. LEVEL OF EVIDENCE: 3.