Vancomycin in Spine Surgery

1. Purpose: The purpose of this study is to examine the efficacy of prophylactic, locally applied vancomycin powder against surgical site infection in patients undergoing posterior instrumented spinal surgery for traumatic injury. 2. Rationale: Surgical site infection (SSI) is a morbid complication with high cost in management of surgical spine patients. In this era of healthcare reforms, adjuvant therapies that not only improve quality, but also decrease cost, are considered of highest value. Despite the use of prophylactic systemic antibiotics and improved surgical technique, surgical site infections remain a serious perioperative concern. In comparison to systemic antibiotics, local delivery of antibiotics is attractive because high concentrations are achieved directly at these sites and systemic toxicity is limited. Prior investigations have primarily focused on the treatment of infected wounds with local antibiotics. Only a few studies have analyzed prophylactic use of local antibiotics during spine surgery. To date, there are no prospective, randomized studies on the prophylactic use of local antibiotics. The investigators will introduce local vancomycin powder into their practice of instrumented posterior spinal fusion for traumatic spine injury and determine efficacy in preventing postoperative infections. 3. Study Population: The study will consist of adult patients undergoing posterior, instrumented spine surgery for traumatic injury. 4. Research Design: This will be a prospective, randomized, controlled trial. The study will primarily be carried out through the University of Tennessee Health Science Center with all spinal surgery taking place at the Regional Medical Center at Memphis. Once patients with traumatic spine injury have been deemed eligible through several other criteria described later in the application, they will be placed into one of two randomized groups: 1\) The control group will consist of patients who are administered systemic prophylactic antibiotic only. 2\) The treatment group will consist of patients who are administered systemic prophylactic antibiotic along with vancomycin powder within the surgical site. 5\. Study/Project Procedures: Patients who meet the entry criteria and agree to participate in the trial will be randomized to receive intraoperative vancomycin powder within the surgical wound or not. In all patients, vancomycin 1g and cefazolin 2g IV will be given within 60min of skin incision. If an allergy to cefazolin exists, 900mg of clindamycin IV will be used in its place. Cefazolin 1g IV will be given q6hr during surgery and continued q8hr post surgery for 24hrs, regardless of whether a surgical drain is in place. One to three liters of normal saline will be used for irrigation purposes during surgical procedure. Prior to wound closure, vancomycin powder will be topically applied both above (50% of dose) and below (50% of dose) the deep muscular fascia in patients participating in the treatment arm of the study. For surgeries involving 3 contiguous spinal segments or less, 500mg of vancomycin (1/2 vial) will be applied. For surgeries involving greater than 3 contiguous spinal segments, 1gm will be applied. 6\. Outcome Measures: All patients will be followed on an inpatient or outpatient basis (as applicable) for a period of 12 months post-operatively. Residents, attendings and study coordinators will perform data collection. All patients with suspected wound infection will undergo MRI with contrast for verification, unless there is gross evidence of infection (ex. purulent drainage from the incision, erythema and swelling). A CT scan with contrast will be obtained in those patients who are unable to undergo MRI for various reasons (pacemaker, metallic foreign bodies, fresh vascular stents, etc.). All wound data will be collected and recorded in specific data forms at each clinical encounter.