Urinary Tract Infection Following Posterior Lumbar Fusion Procedures An American College of Surgeons National Surgical Quality Improvement Program Study

Study Design. Retrospective review of prospectively collected data. Objective. To determine the incidence and risk factors for the development of a urinary tract infection (UTI) after a posterior lumbar fusion procedure. Summary of Background Data. UTI after surgery is common and has important clinical consequences for both patients and the health care system. Few studies have examined UTI after spinal fusion procedures. Methods. Patients undergoing posterior lumbar fusion procedures during 2011 to 2013 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Statistical comparisons were made using multivariate regression with adjustment for demographic, comorbidity, and operative characteristics. Results. A total of 10,825 patients met inclusion criteria. The incidence of a UTI was 1.77% (95% confidence interval = 1.52%-2.02%). Independent risk factors for a UTI were greater age (for 50 59 yr, relative risk [RR] = 1.0; 60 69 yr, RR = 2.1; >= 70 yr, RR = 3.5; P < 0.001), female sex (RR = 2.2, P < 0.001), dependent functional status (RR = 2.1, P = 0.010), malnutrition (RR = 2.3, P = 0.004), diabetic status (for non-insulin-dependent diabetes, RR = 1.5; for insulin-dependent diabetes, RR = 1.9; P = 0.011), and increased operative duration (for 120-179 min, RR = 1.4; 180-239 min, RR = 2.3; and for >= 240 min, RR = 2.7; P < 0.001). Patients who developed a UTI had a greater risk for systemic sepsis than other patients (11.5% vs. 0.63%; adjusted RR = 14.4, P < 0.001). Patients who developed a UTI had a greater risk for readmission than other patients (36.7% vs. 5.0%; adjusted RR = 6.1, P < 0.001). Conclusion. UTIs occur in nearly 1 in 50 patients undergoing posterior lumbar fusion procedures. Patients who are older, female, dependent, malnourished, or diabetic are at greater risk and should be counseled and monitored accordingly. In addition, morbidity associated with a UTI in this population is substantial, as demonstrated by a 14-fold increase in the risk for systemic sepsis and a 6-fold increase in the risk for readmission. As such, increased preventative measures should be targeted to the patients identified here to be at greatest risk.