Pedicle flap reconstruction for treatment of infected median sternotomy wounds after cardiac surgery in overweight and obese patients: proposal of a management algorithm based on a case series analysis

BACKGROUND: A relationship between obesity and adverse outcomes in patients with post-sternotomy wounds undergoing pedicle flap reconstruction is not well-documented. In this study, we present a single-centre retrospective case series analysis of early postoperative outcomes of patients with infected post-sternotomy wounds undergoing pedicle flap reconstruction. We also propose a management algorithm for such patients, based on BMI and wound width. METHODS: We retrospectively analyzed all patients, who underwent pedicle flap reconstruction for major sternal wound infections after sternotomy for cardiac surgery in a tertiary hospital in Germany during a 5-year period. Exclusion criteria included patients younger than 18 years of age and patients with BMI < 18.5 kg/m(2). Patients were divided into 2 groups according to BMI: normal-weight (NW; BMI < 25 kg/m(2)) and overweight/obese (OB/OW; BMI > 25 kg/m(2)). Both groups were compared in terms of preoperative parameters and early postoperative outcomes. Preoperative parameters included demographics, wound bacteria and comorbidities. Postoperative outcomes included duration of surgery time (from incision to skin closure), transfusion requirement (during surgery and entire hospital stay), onset of flap and donor-site complications, length of stay and 30-day mortality. We employed the two-tailed t-test to compare continuous variables and the two-sided Fischer’s exact test to compare categorical variables. Statistical significance was set at p < 0.05. RESULTS: The total sample consisted of 48 patients. Overall mean BMI was 28.4 (6.1) kg/m(2). Mean age was 67 (12) years. The study group consisted of 28 patients with BMI > 25 kg/m(2), who were compared with 20 normal-weight patients. There was a significant difference amongst both groups regarding duration of surgery (120 vs. 174 min, p < 0.05). Donor-site complications requiring intervention were observed in 30% of patients in both groups. Flap-related complications were recorded in 16 (57%) cases in the study group and 7 cases in the control group (35%, p = 0.15). CONCLUSIONS: We conclude that wound width and BMI can aid the decision-making process for patients with infected sternal wounds after cardiac surgery requiring pedicle flap reconstruction. However, in our case series analysis, OB/OW patients were not found to be at statistically significantly increased risk for worse postoperative outcomes, but were associated with a longer duration of surgery.