12 - Management of Serous Wound Drainage following Spinal Surgery: Is Empiric Oral Antibiotic Treatment Appropriate?

Introduction: The role of empiric oral antibiotic treatment in the management of serous wound drainage following spine surgery is controversial. While there may be a clear rationale for prescribing oral antibiotics in patients reporting purulent discharge from their incision after spinal surgery, it is less clear if oral antibiotics decrease the rate of incision and drainage (I&D) for patients who have serous drainage without initial signs of a surgical site infection.

Objective: To determine if there is a benefit to prescribing empiric oral antibiotic treatment for patient-reported serous wound drainage.

Methods: At a large tertiary-care spine center, a consecutive series of patients were identified from a prospectively maintained postoperative phone call log. Three hundred thirty one (331) patients called into the office reporting wound concerns. Serous drainage from the surgical incision without obvious signs/symptoms of infection was reported by 90% of the patients (298/311). Empiric oral antibiotics were prescribed to 38% (112/298) based on the treating surgeon’s preference. In order to control for selection bias, patients who received antibiotics (AbxTx) were propensity matched to patients who did not (No AbxTx) based on sex, age, BMI, ASA grade, smoking status, prior spine surgery, anatomic location and number of surgical levels. The number of patients who developed a subsequent SSI requiring a surgical I&D were determined.

Methods: The demographic and surgical characteristics of the two cohorts were similar. Although there were more patients in the AbxTx group who required an I&D (n=17, 17%) compared to the No AbxTx group (n=9, 9%), this difference was not statistically significant (p=0.139). The intra-operative culture results showed no growth in almost all the patients requiring an I&D in AbxTx group (16/17, 94%) and in 67% (6/9) in the No AbxTx group (p=0.103). One patient in each group required a return to the operating room within the year after the initial I&D for instrumentation removal and repeat I&D for chronic infection.

Conclusions: In this large series (n=331) of patients with serous wound drainage after home discharge following spine surgery, 87% resolved without the need for repeat surgical intervention. Empiric treatment with oral antibiotics did not reduce the need for a future incision and drainage or the development of a chronic infection.