Utility of Preoperative Laboratory Testing in Assessing Risk of Adverse Outcomes After Anterior Cervical Discectomy and Fusion: Insights from National Surgical Registry

Background: Preoperative laboratory tests are varied in their administration among physicians, and previous studies have published conflicting reports on their utility. Anterior cervical discectomy and fusion (ACDF) is a commonly performed spine surgery, and patients often undergo preoperative testing. We sought to assess the relationship between preoperative laboratory values and risk for adverse postoperative outcomes after ACDF. Methods: The American College of Surgeons–National Surgical Quality Improvement Program was queried from 2012 to 2017 to identify patients undergoing elective ACDF. Multivariable logistic regression was performed to assess the association between abnormal laboratory test values and adverse 30-day outcomes. Relative predictor importance was determined using an importance metric defined as Wald χ² penalized by degrees of freedom. Results: A total of 47,111 patients were included. On multivariable analysis, high creatinine (P = 0.030), anemia (P < 0.001), hyponatremia (P = 0.034), and leukocytosis (P < 0.001) were found to be significantly associated with any 30-day complications. Anemia (P < 0.001), hypernatremia (P = 0.028), hyponatremia (P = 0.016), and leukocytosis (P < 0.001) were found to be significantly associated with serious 30-day complications. High creatinine (P = 0.027), anemia (P < 0.001), hyponatremia (P = 0.047), and leukocytosis (P = 0.004) were found to be significantly associated with 30-day unplanned readmissions. High blood urea nitrogen (P = 0.007), high creatinine (P = 0.028), anemia (P < 0.001), low platelet count (P < 0.001), hyponatremia (P < 0.001), and leukocytosis (P < 0.001) were found to be significantly associated with nonhome discharge. Predictor importance analysis revealed that abnormal preoperative laboratory values were important determinants in predicting these 30-day outcomes. Conclusions: Our analyses indicate that abnormal preoperative laboratory values are associated with increased risk for adverse outcomes after elective ACDF and can be used in predictive analyses of outcomes.