Impact of Gentamicin-Collagen Sponge (Collatamp) on the Incidence of Sternal Wound Infection in High-Risk Cardiac Surgery Patients: A Propensity Score Analysis

Objective: Local delivery of prophylactic antibiotic to the wound site with an implanted, reabsorbable, gentamicin-containing collagen sponge (Collatamp) is a strategy that has been claimed to prevent sternal wound infection after cardiac surgery. The purpose of this study was to review our experience with Collatamp in cardiac surgery patients deemed at high risk for sternal wound infection. Methods: From January 2007 to December 2010, Collatamp was used in 107 patients deemed at high risk for sternal wound infection. Applying the propensity score, we matched 97 patients with Collatamp (group I) with 97 patients who did not receive Collatamp (group II). All individuals received routine intravenous antimicrobial prophylaxis. Postoperative wound-infection rates as well as routine outcomes were compared. Information for the study was obtained from the cardiac surgical Patients Analysis and Tracking System (PATS) database and from hospital records. Results: The superficial sternal wound infection rate was 2.1% (2/97) in group I and 6.2% (6/97) in group II (P=.01). The rates of deep sternal wound infection rate were similar (2.1% versus 3.1%, P=.87). There was no mediastinitis in the study population. In addition, more patients in group II received an intra-aortic balloon pump (5.2% versus 2.1%, P=.04) and underwent hemofiltration (7.2% versus 3.1%, P=.02). No side effects were noted. Conclusion: Gentamicin-containing collagen sponge (Collatamp) is a useful adjunct to meticulous surgical technique and postoperative wound care in reducing the incidence of sternal wound infection in high-risk cardiac surgery patients. An adequately powered study is needed, however, to validate the safety and efficacy of this strategy.