Flap Reconstruction for Deep Sternal Wound Infections: Factors Influencing Morbidity and Mortality

Abstract Background Deep sternal wound infections (DSWI) often require flap reconstruction to obliterate dead space and provide healthy soft tissue coverage. A better understanding of risk factors for complications following DSWI flap reconstruction may improve operative management. Methods A retrospective study (2007-2018) was conducted of all patients with DSWI following cardiothoracic surgery referred to a single reconstructive surgeon for flap reconstruction. Patient and operative factors were reviewed including procedure types and outcomes. Predictors of morbidity and mortality were analyzed. Results 119 patients requiring flap reconstruction for DSWI met inclusion criteria. Unilateral (49.6%) or bilateral (40.3%) pectoralis muscle flaps were performed most frequently, followed by vertical rectus abdominus myocutaneous (VRAM) (4.2%), omental (4.2%), and omental/pectoralis flap combination (1.7%). Superficial surgical site infection (SSI) was the predominant post-operative complication (17.6%). Nineteen patients (16%) required debridement/revisional procedures and five (4.2%) suffered flap failure. Overall 30-day mortality was 15.1%. End-stage renal disease (p=0.002), congestive heart failure (p=0.049), low albumin (p=0.004), cardiopulmonary bypass time (p=0.0001), need for open chest (p=0.020), and high ASA classification (p=0.003) were associated with mortality. By multivariate analysis, multidrug resistance (MDR) was predictive of any post-operative complication (OR=5.6 p=0.018, CI [1.3-23.2]), VRAM was predictive of SSI (OR=9.6, p=0.022 CI [1.4-66.4]), and end-stage renal disease (OR=8.57, p=0.044, CI [1.06-69.1]) was predictive of mortality. Conclusions Pectoralis muscle flaps are the workhorse for complex sternal wound coverage, but complications following flap reconstruction for DSWIs remain high. In particular, end-stage renal disease, VRAM reconstruction and MDR infection may predict a complicated post-operative course in these patients.