Incidence, prevalence, and analysis of risk factors for surgical site infection following adult spinal surgery.

A retrospective cohort study to identify rates and analyze the risk factors for postoperative spinal wound infection. To determine significant risk factors for postoperative spinal wound infection by comparing those patients who developed a postoperative wound infection with the rest of the cohort. A surgical site infection (SSI) is a common complication after spinal surgery. SSI leads to higher morbidity, mortality, and healthcare costs. To develop strategies to reduce the risk for SSI, independent risk factors for SSI should be identified. The electronic patient record of all 3174 patients who underwent orthopedic spinal surgery at out institution were abstracted. Individual patient and perioperative characteristics were stored in an electronic database. In total, 132 (4.2%) patients were found to have an SSI with 84 having deep based infection. Estimated blood loss over 1 liter (P = 0.017), previous SSI (P = 0.012) and diabetes (P = 0.050) were found to be independent statistically significant risk factors for SSI. Obesity (P = 0.009) was found to significantly increase the risk of superficial infection, whereas anterior spinal approach decreased the risk (P = 0.010). Diabetes (P = 0.033), obesity (P = 0.047), previous SSI (P = 0.009), and longer surgeries (2-5 hours [P = 0.023] and 5 or more hours [P = 0.009]) were found to be independent significant risk factors for deep SSI. SSI is commonly seen after spinal surgery. In our study, we identified independent risk factors for both deep and superficial SSI. Identification of these risk factors should allow us to design protocols to decrease the risk of SSE in future patients.