Impact of Delayed Sternal Closure on Wound Infections following Paediatric Cardiac Surgery

Objectives: Delayed sternal closure (DSC) is a well-established procedure to reduce postoperative hemodynamic and respiratory instability following neonatal or infant cardiac surgery. Though, DSC is thought to be associated with increased rates of sternal wound infection (SWI), sepsis and mortality. Indication and duration of DSC vary between pediatric cardiac centers worldwide. Therefore, we reviewed our experience with DSC to determine the incidence of SWI and to evaluate potential perioperative risk factors.

Methods: A retrospective study was conducted within a cohort of pediatric cardiac surgery patients undergoing DSC between January 2013 and May 2017 at our institution. Criteria for study inclusion were patient age < 3 years and patient survival of DSC for at least 7 days. Cases of SWI were classified as superficial, deep and mediastinal. DSC was routinely performed after stage 1 palliation for single-ventricle disease. In all other cases decision for DSC was made on surgeon’s discretion. To identify SWI risk factors uni- and multivariate logistic regression analysis were calculated.

Results: A total of 130 patients (male sex: 61.5%; age: 13.5 ± 119 days; weight 3.8 ± 1.4 kg) underwent DSC at our institution. Single ventricle palliation was performed in 19 cases (14.6%). Mean duration of sternal opening was 4.3 days (1 to 28 days). 13 patients (10%) developed a SWI (12 superficial, 1 deep). Surgical revision was necessary in 1 case (deep infection). The main SWI pathogens identified from culture were staphylococcus aureus, coagulase-negative staphylococcus and staphylococcus epidermidis. 30-day-Survival and 1-year-Survival were 93.8% and 85.6%, respectively. Former support with ECMO was identified as significant perioperative risk factor for SWI (p = 0.04). There was no significant correlation between SWI and duration of sternal opening for more than 4 days, cardiopulmonary bypass time (>180min), aortic clamp time (>60min), length of ICU stay (>7days), usage of foreign material during operation and mortality.

Conclusion: DSC is a safe and accepted procedure to avoid postoperative hemodynamic instability. However, DSC is thought to be associated with a potential risk of infection, especially in patients after mechanical circulatory support with ECMO. However, surgical revision is rarely needed.