Wound Complications After Median Sternotomy: a Single-centre Study

Objectives: Sternal wound complications following median sternotomy remain a challenge in cardiac surgery. Changes in both patient profile and type of operations have been observed in recent years. Therefore, we analysed current wound healing complications after median sternotomy at our centre.

Methods: All adult patients undergoing a median sternotomy between January 2009 and April 2011 were included in this retrospective analysis. Transplants and assist devices implantations were omitted. We assessed outcome, prognostic factors and microbiological results of standardized wound swabs.

Results: In total, 1297 patients with an average age of 67.0 ± 12.7 years were analysed. Operation types included 598 solitary coronary artery bypass grafts (CABGs), 213 solitary valve procedures, 105 CABGs with aortic valve replacement and 116 solitary aortic operations or conduit implantations. Furthermore, 255 of the remaining 265 were combined or otherwise complex procedures. Superficial healing disorders occurred in 43 patients (3.3%), while 33 (2.5%) developed deep wound complications. Six patients with sternal wound complications (7.9%) died in-hospital. In 7 patients, no pathogen was identified and the wound appeared uninfected (21% of all deep complications or 0.05% of all patients). These healing disorders were considered deep dehiscences. Patients with insulin-dependent diabetes mellitus, BMI of >40 kg/m(2) and who underwent reoperation were prone to superficial infections. Risk factors for all deep sternal wound complications were insulin-dependent diabetes mellitus, COPD and reoperation. Moreover, multivariate analysis revealed 'emergency' as an independent prognostic factor for all sternal wound complications. Microbial swabs of the sternal wound were taken in 82 of the 1297 patients (6.6%). Pathogens of the normal skin flora represented the majority of pathogens in both superficial and deep wound complications. Eight patients with deep, but only 2 patients with superficial complications suffered from polymicrobial infections. All deep polymicrobial infections involved coagulase-negative Staphylococci.

Conclusions: Wound complications following median sternotomy remain a challenge to cardiac surgery. Redo and emergency operations are the most important risk factors in this contemporary series. More efforts seem mandatory to decrease this arduous morbidity and the costs of prolonged treatment.