Does Intrawound Vancomycin Decrease Postoperative Surgical Site Infection in Spine Surgery: A Retrospective Case-control Study.

Study design: Retrospective Case-Control series.

Objective: The objective of this study is to define the overall postoperative rate of surgical site infection (SSI) in patients undergoing spine surgery and examine the effects of intrawound Vancomycin on postoperative infection rates.

Summary of background data: Surgical site infections (SSI) account for 22% of all health care-associated infections. The use of intrawound Vancomycin in an attempt to reduce the incidence of postoperative SSI has not been sufficiently evaluated in the existing literature.

Methods: All spine surgeries (n=19,081) from our institution were reviewed from 2003 to 2013. All cases of verified SSI were identified from the database. Cases were then matched to controls in a 1:1 fashion based on age, gender, and date of surgery (+/-30 d). Patient demographics, comorbidities, estimated blood loss, duration of surgery, intrawound administration of Vancomycin, and smoking status were evaluated.

Results: At total of 316 cases of SSI after spine surgery were identified, representing an infection rate of 1.7%. The mean follow-up for cases and controls was 31.5 and 41.6 months, respectively. OR for intrawound Vancomycin was 0.44 (95% CI 0.23-0.88, P =0.019). OR for BMI greater than 30 was 1.63 (95% CI 1.04-2.56, P =0.03).

Conclusions: In this large cohort of spine surgery patients, administration of intrawound Vancomycin was associated with a significant reduction in postoperative surgical site infections. Further studies are needed to determine appropriate dosing and application as well as long-term safety in spine surgery.