Gentamicin-collagen sponge reduces the risk of sternal wound infections after heart surgery: Meta-analysis

Objectives: Sternal wound infections are serious postoperative complications that increase the length of hospital stay and healthcare costs. The benefit of implantable gentamicin-collagen sponges in reducing sternal wound infections has been questioned in a recent multicenter trial. We aimed to perform a comprehensive metaanalysis of studies assessing the efficacy of implantable gentamicin-collagen sponges in sternal wound infection prevention. Methods: Multiple databases were screened for studies assessing the efficacy of implantable gentamicin-collagen sponges after heart surgery. The primary end point was sternal wound infection, and secondary end points were the occurrence of deep sternalwound infection, superficial sternalwound infection, mediastinitis, and mortality. Randomized controlled trials and observational studies were analyzed separately. By means of meta-regression, we examined the correlation between sternal wound infection and extent to which the bilateral internal thoracic artery was harvested. Results: A total of 14 studies (N = 22,135, among them 4 randomized controlled trials [N = 4672]) were included in the analysis. Implantable gentamicin-collagen sponges significantly reduced the risk of sternal wound infection by approximately 40% when compared with control (risk ratio [RR], 0.61; 95% confidence interval [CI], 0.39-0.98; P = .04 for randomized controlled trials and RR, 0.61; 95% CI, 0.42-0.89; P = .01 for observational studies). A similar, significant benefit was demonstrated for deep sternal wound infection (RR, 0.60; 95% CI, 0.42-0.88; P = .008) and superficial sternal wound infection (RR, 0.60; 95% CI, 0.430.83; P = .002). The overall analysis revealed a reduced risk of mediastinitis (RR, 0.64; 95% CI, 0.45-0.91; P = .01). The risk of death was unchanged. A significant positive linear correlation (P = .05) was found between the log RR of sternal wound infection and the percentage of patients receiving bilateral internal thoracic artery grafts. Conclusions: Implantable gentamicin-collagen sponges significantly reduce the risk of sternal wound infection after cardiac surgery, with evidence consistent in randomized and observational-level data. However, the extent of this benefit might be attenuated in patients receiving bilateral internal thoracic artery grafts.