Postoperative surgical site infections in patients undergoing spinal tumor surgery: incidence and risk factors.

STUDY DESIGN

We conducted a retrospective, case control study on patients undergoing surgery for spinal tumors. OBJECTIVE.: Our aim was to determine the incidence and to identify risk factors for surgical site infections (SSIs) in patients undergoing surgery for spinal tumors.

SUMMARY OF BACKGROUND DATA

SSIs after spinal tumor surgery may be particularly devastating as they may add to substantial surgical morbidity and may further exacerbate already existing neurologic deficits. Incidence and risk factors predisposing to SSIs in patients undergoing surgery for spinal tumors are not well studied yet.

METHODS

Between January 1995 and February 2008, 971 procedures for spinal tumors were performed on 739 patients. Excluding sacral tumors from the current study, 895 procedures on 678 patients were reviewed to identify those cases with SSIs. Furthermore, 65 infected cases and a randomly selected subset of 162 controls were analyzed by logistic regression modeling to identify the risk factors associated with SSIs.

RESULTS

There were 678 patients that were included in this study with 364 men (54%) and 314 women (46%), with an average age of 47.2 year. Sixty-five patients who developed SSIs underwent a total of 162 procedures including 78 procedures for wound debridement and washout. The incidence of SSIs was 8.89% for primary nonbony spinal tumors, 9.5% for metastatic spinal tumors, and 13.7% for primary bony spinal tumors. Staphylococcus aureus was the most commonly isolated organism (n = 22 of 65, 33%). In the multivariate logistic regression model, previous spinal surgeries, complex plastic closures, increasing number of comorbidities, presence of a hospital acquired infection at the time of a previous surgery, and increasing duration of hospital stay during primary surgery were significantly associated with increased likelihood of developing postoperative SSIs.

CONCLUSION

Surgery for spine tumors appears to be associated with a higher incidence of SSI than nontumor spine surgery. Identification of perioperative risk factors will help delineate this subset of patients with high risk for developing SSIs thus potentially allowing perioperative modification for such factors, which may lead to an overall better clinical outcome and patient satisfaction.