Journal de la colonne vertébrale

Is postoperative Antimicrobial Prophylaxis Needed for the Management of Surgical Site Infection after Spinal Instrumentation Surgery?

Abstract

Takuya Numasawa, Atsushi Ono, Kanichiro Wada, Yamasaki, Gentaro Kumagai, Toru Yokoyama, Kazumasa Ueyama, Satoshi Toh and Yasuyuk Ishibashi

Background: It is widely accepted that postoperative Antimicrobial Prophylaxis (AMP) is effective in reducing the risk of surgical site infections (SSI) following spinal surgery. After publication of the Guideline for Prevention of Surgical Site Infection by the Centers for Disease Control and Prevention in 1999, a large number of studies confirmed the effectiveness of AMP. Due to the possible emergence of AMP resistant bacteria or appearance of side-effects, we have treated and managed patients who underwent spinal surgery without post operative antimicrobial agents since 2003.

Purpose: To investigate the incidence of SSI in patients without administration of antibiotics after spinal instrumentation surgery.

Subjects: A consecutive 468 patients (230 males and 238 females) were adopted in this study from November 2003 to June 2010. Mean age at the time of operation was 52.1 years. We defined this group as the non-postoperative dose group. There were 121 patients (25.9%) who underwent instrumentation surgery. On the other hand, we defined patients who were administered postoperative multiple doses of AMP between January 2000 and October 2003 as the postoperative dose group. There were 340 cases, consisting of 198 males and 142 females in this group. Average age at the time of operation was 51.3 years. There were 146 patients (42.9%) who underwent spinal instrumentation surgery.

Methods: All patients were administered 1 g of cefazolin within 30 minutes of skin incision, and the same dose of antimicrobial agent was added every four hours during surgery in the non-postoperative dose group. We administered AMP before and for 7 days after surgery in the postoperative dose group.

Results: The postoperative infection rate was 1.92% (9 cases), of which 7 cases were superficial infections and 2 cases were deep infections in the non-post operative dose group. In the post operative dose group, there were 9 confirmed post operative wound infections in the 340 patients for an overall SSI rate of 2.65%. There was no significant difference between the two groups. The incidence of SSI in patients who underwent spinal instrumentation surgery was 0.83% (one of 121 patients) in the non-postoperative dose group and 2.04% (three of 147 patients) in the postoperative dose group. There was no significant difference between the two groups even with the use of spinal implants.

Conclusions: The duration of antimicrobial prophylaxis was not related to the SSI rate at our institution. Postoperative administration of antibiotics appears to be unnecessary for spinal surgery even with spinal implants when perioperative management was achieved for the patient condition and surroundings as recommended in the CDC guidelines.