Post-operative hyperglycemia and its association with surgical site infection after instrumented spinal fusion.

ABSTRACT

OBJECTIVE: To evaluate the correlation between postoperative hyperglycemia and surgical site infection among patients who underwent primary instrumented spinal fusion surgery. PATIENTS AND METHODS: We collected data on all eligible patients treated at our institution over the course of 2005-2017. We defined serum hyperglycemia using a primary threshold of serum glucose ≥140 mg/dL and used ≥115 mg/dL as a secondary test. We used logistic regression techniques to evaluate unadjusted results for serum hyperglycemia on revision surgeries for infection, followed by sequential adjustment for sociodemographic and procedural characteristics. RESULTS: We included 3664 patients. Surgical site infections occurred in 4%. Post-operative hyperglycemia was significantly associated with a higher rate of revision surgery for infection (p = 0.02). Following adjusted analysis, hyperglycemia remained a statistically significant predictor for revision surgery due to infection (OR 2.19; 95 % CI 1.13, 4.25). Similar results were evident when using the lower threshold of ≥115 mg/dL (OR 2.36; 95 % CI 1.06, 5.23). CONCLUSIONS: This study highlights the importance of measuring serum glucose after spinal fusion and the need for heightened surveillance and/or treatment in those who exhibit postoperative hyperglycemia. In this context, it could be advantageous to use a lower threshold for hyperglycemia (115 mg/dL) in order to trigger interventions for glycemic control.