Comparison of local gentamicin-collagen versus a simple collagen sponge on the incidence of sternal wound infections: A prospective randomized double-blind controlled trial

Objectives: The benefit of prophylactic use of local gentamicin-collagen sponge on the incidence of sternal wound infections is actually a matter of debate. The aim of the present study is to compare the incidence of deep (DSWI),- and superficial (SSWI) sternal wound infection after implementation of a gentamicin-collagen sponge (verum) versus a simple collagen sponge (placebo) just before closure of median sternotomy.

Methods: We present 800 consecutive cardiac surgery patients prospectively randomised in a double-blind design to receive either (group I) a gentamicin-collagen sponge (5×20×0.5cm total gentamicin of 110.5–143mg) or (group II) a simple collagen sponge (placebo) retrosternally. Primary end-points were DSWI and SSWI through 30 days postoperatively; secondary end-points included a composite of clinical parameters. All patients received standardized care including prophylactic systemic antibiotics (cefuroxime) and conventional sternal closure (peri/transsternal wiring).

Results: 723/800 (90.4%) patients were involved in the study; group I (verum) involved 354 (49%) and group II (placebo) involved 369 (51%) patients. Patient characteristics, comorbidities, and procedure-related variables were similar in both groups. Overall incidence of DSWI/SSWI was 2.1%/2.5%; group I (2/354; 0.56%)/(7/354; 1.9%) versus group II (13/369; 3.5%)/(11/369; 2.9%); relative risk reduction of 83.9%/33.7%, p=0.013. No statistically significant differences were demonstrated concerning secondary end-points, like postoperative bleeding and transfusion of red-cell units, thrombocyts and fresh-frozen-plasma.

Conclusion: This study has shown a significant reduction in DSWI and SSWI in patients undergoing median sternotomy for cardiac surgery with routinely application of a collagen-genatmicin sponge.