How Big Is Too Big? The Effect of Defect Size on Postoperative Complications of Vertical Rectus Abdominis Flap Reconstruction

Background The vertical rectus abdominis myocutaneous (VRAM) flap has been frequently used for perineal reconstruction given the high potential for wound complications associated with direct closure of this area. However, the relationship between defect size and postoperative complications remains undefined. Methods A retrospective chart review of the last 20 years for VRAM flaps was performed. Defect size, age, body mass index (BMI), cause of defect, sex, radiation, and flap donor laterality were recorded. Complications of infection, partial flap loss, total flap loss, minor wounds, treated nonoperatively, and major wound, which required reoperation, were analyzed with respect to defect size. Descriptive statistics were used to summarize the demographic and clinical characteristics of the included patients. Associations were assessed using binary logistic regression analysis, and difference in means for compared groups was assessed using the independent samples t test. P values were set at 5% for all comparisons. Results There were 65 patients with VRAM flaps identified during the review period. Mean defect size was 204.71 cm(2). Mean age was 63.97, and mean BMI was 27.18. History of prior radiation was noted in 90.77% of patients (n = 59). When adjusted for age and BMI, mean defect area was significantly different for patients with minor or major wounds. Larger perineal defects were associated with increased risk of major wound complications (odds ratio, 1.012; 95% confidence interval, 1.003-1.022). Conclusions The vertical rectus abdominis flap has been a workhorse flap for perineal reconstruction. Defect size does not affect risk of partial flap necrosis, complete flap loss, infection, abdominal fascial dehiscence, ventral hernia, or seroma, which supports the utility of VRAM flap for perineal reconstruction. Larger perineal defects are associated with increased risk for major wound complications, which required reoperation, regardless of age or BMI. Future studies should be performed to determine if there is a maximum defect size cutoff that limits the utility of VRAM flap reconstruction or to develop a predictive model to assess the risk of major wound complications based on defect size.