272 - Risk Factors Associated with Wound Complications Following Lumbar Spin...

#272 Risk Factors Associated with Wound Complications Following Lumbar Spine Surgery for Degenerative Pathologies

Epidemiology/Natural History

Poster Presented by: K. Singh


A.J. Marquez-Lara (1)
S.V. Nandyala (1)
S.J. Fineberg (1)
M. Noureldin (1)
K. Singh (1)

(1) Rush University Medical Center, Orthopaedic Surgery, Chicago, IL, United States


Introduction: A surgical site infection (SSI) is one of the most common complications after orthopaedic procedures. The incidence as well as the risk factors associated with a SSI after a lumbar spine surgery (LSS) has been poorly reported. A national surgical database was utilized to analyze preoperative and intraoperative variables in order to determine the risk factors predisposing patients to a SSI following a LSS procedure.

Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried to identify patients who underwent an elective LSS procedure for degenerative diagnoses between 2006-2011. The resulting cohort was divided between patients who had a SSI and those who did not. A SSI included superficial or deep incisional infection, deep organ space infection, or wound dehiscence. Preoperative patient characteristics (demographics, comorbidities, preoperative lab values), perioperative outcomes (e.g., operative time, length of stay (LOS), 30-day complication rates, and mortality) were compared between groups. SPSS v.20 was utilized for statistical analysis with independent t-tests and χ2-tests for continuous and categorical variables respectively. A multinomial regression analysis determined independent predictors for a SSI after controlling for demographics and comorbidities. A p-value of ≤0.001 was considered statistically significant.

Results: A total of 22,676 lumbar spine surgeries were identified from 2006-2011, of which 462 (2.0%) developed a postoperative SSI. Patient risk factors that increased the likelihood of an SSI included a history of diabetes, hypertension, dialysis, stroke, open or infected wounds, steroid use, and bleeding disorders. Patients who suffered wound complications also had significantly lower hematocrit and serum albumin, as well as increased serum creatinine levels compared to unaffected patients. Wound complications were also associated with a higher ASA class, a dirty or contaminated wound class, longer operative times, greater resident involvement and an increased number of blood transfusions. In addition, the affected cohort demonstrated a greater LOS and incurred greater rates of readmission/reoperations and sepsis. In the multivariate analysis, statistically significant predictors for wound complications included female gender (OR 1.39), obesity (OR 1.81), diabetes (OR 1.53), dialysis (OR 4.1), steroid use (OR 2.03), bleeding disorders (OR 2.31), resident involvement (OR 1.64) and increased operative times (OR 1.003).

Conclusion: This study utilizes the National Surgical Quality Improvement Program to examine preoperative and intraoperative risk factors associated with a SSI following a LSS procedure. Multivariate regression analysis demonstrated that the independent risk factors for a SSI included female gender, obesity, diabetes, dialysis, steroid use, bleeding disorders, resident involvement, and increased operative time. Development of pre-operative protocols based upon these identified risk factors may help decrease the morbidity, length of stay and hospital costs associated with lumbar wound complications.