Can the American College of Surgeons Risk Calculator Predict 30-day Complications after Spine Surgery?

Abstract

Study Design.Retrospective cohort study.Objective.The aim of this study was to assess the American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) Risk Calculator's ability to predict 30-day complications after spine surgery.Summary of Background Data.Surgical risk calculators may identify patients at increased risk for complications, improve outcomes, enhance the informed consent process, and help modify risk factors. The ACS NSQIP Risk Calculator was developed from a cohort of >1.4 million patients, using 2805 unique CPT codes. It uses 21 patient predictors and the planned procedure to predict the risk of 12 different outcomes within 30 days following surgery.Methods.A retrospective chart review was performed on patients who underwent primary lumbar and cervical fusions with at least 30-day postoperative follow-up between 2009 and 2015 at a single-institution. Descriptive statistics were calculated for the overall sample, anterior versus posterior fusion (cervical only), and single versus multilevel fusion. Logistic regression models were fit with actual complication occurrence as the dependent variable in each model and ACS estimated risk as the independent variable. The c-statistic was used as the measure of concordance for each model. Receiver-operating charateristic curves depicted the predictive ability of the estimated risks. Acceptable concordance was set at c >0.80.Results.A total of 237 lumbar and 404 cervical patients were included in the study. The Risk Calculator risk estimates significantly predicted (P < 0.001) "any complication"and "discharge to skilled nursing facility"among the cervical cohort and demonstrated no significant outcome prediction the lumbar cohort.Conclusion.The ACS Risk-Calculator accurately predicted complications in the categories of "any complication"and "discharge to skilled nursing facility"for our cervical cohort and failed to demonstrate benefit for our lumbar cohort. Although the ACS Risk-Calculator may be useful in general surgery, our findings demonstrate that it does not necessarily provide accurate information for patients undergoing spinal surgery.Level of Evidence: 3.