Postoperative Fever Evaluation Following Lumbar Fusion Procedures

OBJECTIVE: This study aimed to determine the incidence of postoperative fever, the workup conducted for postoperative fever, the rate of subsequent fever-related diagnoses or complications, and the risk factors associated with fever following lumbar fusion. METHODS: A retrospective review of patients undergoing lumbar fusion was performed. For patients in whom fever (≥38.6°C) was documented, charts were reviewed for any fever workup or diagnosis. Multivariate regression was used to identify independent risk factors for the development of postoperative fever. RESULTS: A total of 868 patients met the inclusion criteria, of whom 105 exhibited at least 1 episode of fever during hospitalization. The first documentation of fever occurred during the first 24 hours in 43.8% of cases, during postoperative hours 24–48 in 53.3%, and later than 48 hours postoperatively in 2.9%. At least 1 component of a fever workup was conducted in 47 of the 105 patients who had fever, resulting in fever-associated diagnoses in 4 patients prior to discharge. Three patients who had fever during the inpatient stay developed complications after discharge. On multivariate analysis, operations longer than 150 minutes (relative risk [RR], 1.66; p=0.015) and narcotic consumption greater than 85 oral morphine equivalents on postoperative day 0 (RR, 1.53; p=0.038) were independently associated with an increased risk of developing postoperative fever. CONCLUSION: The results of this study suggest that inpatient fever occurred in roughly 1 in 8 patients following lumbar fusion surgery. In most cases where a fever workup was performed, no cause of fever was detected. Longer operative time and increased early postoperative narcotic use may increase the risk of developing postoperative fever.