Factors Influencing Symptomatic and Nonsymptomatic Bulge Rates in the Abdominal Donor Site of Autologous Breast Reconstruction

Abstract

INTRODUCTION: With continued demand for abdominal based breast reconstruction, it is important to understand all the factors influencing donor site morbidity. Previous studies mostly focus on type of flap and its associated donor site complications. However, we aim to assess other factors, including history of prior abdominal surgery, body mass index (BMI), and specific operative details such as the total area of muscle harvested, portion of the rectus muscle harvested, status of the anterior fascia after abdominal closure, use of mesh, and the status of abdominal wall nerves. METHODS: A retrospective chart review of patients undergoing autologous breast reconstruction from May 2012 to October of 2017 by 2 surgeons at a single institution was performed. Only patients with abdominal-based breast reconstruction were included in the study. Demographics, prior medical and surgical history, intraoperative data, and postoperative course were collected. Primary outcomes of interest were nonsymptomatic bulge found on physical exam and symptomatic bulge requiring surgical correction. RESULTS: One-hundred twenty women were identified with 39 undergoing unilateral and 81 undergoing bilateral breast reconstruction. Within the unilateral patient group, 30 patients underwent ms-Transversal Rectus Abdominis Muscle (TRAM) and 9 patients underwent deep inferior epigastric artery perforator (DIEP) reconstruction. The breakdown in the bilateral group is as follows: 39 bilateral ms-TRAM, 5 bilateral DIEP, 37 a combination of ms-TRAM and DIEP. The average follow-up was 2.01 years (range, 0.04–7.52 years). Thirteen (10.8%) patients developed nonsymptomatic bulge and 14 (11.7%) patients developed symptomatic bulge requiring surgical correction. Patient with BMI ≥ 30 were 3 times more likely to develop a symptomatic bulge (P = 0.029). Similarly, patients with prior abdominal surgery were 7.2 times more likely to develop a symptomatic bulge (P = 0.047). Patients with bilateral ms-TRAM reconstruction had higher rate of nonsymptomatic and symptomatic bulge compared with any other reconstruction type (P = 0.050). Size of muscle harvested did not have an effect on bulge development (P = 0.674). Higher percentage of patients with muscle harvested from the central portion of the rectus muscle developed non-symptomatic bulge (P = 0.008). In contrast, patients with muscle harvested from the medial or lateral portion of the rectus muscle had a 15% increased risk of developing symptomatic bulge (P = 0.023 and P = 0.021, respectively). The use of mesh, type of mesh, and location of mesh placement during abdominal wall reconstruction did not affect bulge development (P = 0.236, P = 0.285, P = 0.195, respectively). Whether the anterior rectus fascia was closed or left open at the end of the case did not influence the bulge rate (P = 0.122). Similarly, number of nerves severed did not influence the bulge rate (P = 0.575). CONCLUSION: High BMI and previous abdominal surgery significantly increase the risk of symptomatic bulge development. Location of muscle harvest from the rectus muscle influenced the rates of nonsymptomatic and symptomatic bulge development, with muscle from the central portion of the rectus muscle resulting in significantly higher rate of nonsymptomatic bulge, and muscle from medial or lateral portion of the rectus muscle resulting in higher rate of symptomatic bulge. Total muscle area harvested, use of mesh in abdominal reconstruction, or nerve preservation did not affect the rate of bulge development.