Abstract 118: The Impact of Post-Operative Prophylactic Antibiotics in Immediate 2-Stage Prepectoral Breast Reconstruction

Abstract

PURPOSE: Immediate tissue expander placement remains the preferred method for breast reconstruction after mastectomy. Placement of the prosthesis in the prepectoral rather than submuscular plane is a relatively novel strategy to reduce post-operative pain and potential for animation deformity with overall equivalent cosmetic outcomes. Prophylactic post-operative antibiotic administration is a common practice for reducing reconstructive infection, but raises concerns regarding indiscriminate and prolonged use of antibiotics. Additionally, this has not been studied specifically in the setting of prepectoral tissue expander placement. We sought to determine the impact of routine post-operative antibiotics on complication rates in patients undergoing prepectoral tissue expander placement. METHODS: We retrospectively identified all patients undergoing immediate prepectoral tissue expander placement following mastectomy by a single plastic surgeon from December 2015 to October 2018. We identified two cohorts of patients - one group that received prophylactic antibiotics at the time of discharge, and one group that did not. We collected treatment and outcomes data, and used IBM SPSS Version 23.0 to compare rates of post-operative complications. Our primary outcome was tissue expander loss, and secondary outcomes were infection, skin necrosis, and return to operating room. RESULTS: We identified 69 patients with 115 breasts who received prophylactic antibiotics upon discharge from the hospital, and 63 patients with 106 breasts who did not. There were no significant differences between the groups in terms of age, indications for mastectomy, or comorbidities. The group receiving antibiotics had significantly more patients who received neoadjuvant chemotherapy (42% vs. 28%; p=0.037) and underwent nipple-sparing mastectomies (88% vs. 79%; p=0.031). The antibiotic group had significantly lower rates of tissue expander loss, infection, and return to the OR. There was no difference in skin necrosis rates. CONCLUSION: No current guidelines exist to guide routine antibiotic use following immediate breast reconstruction with prepectoral tissue expanders. These data show a strong association between post-operative antibiotics and reduced post-operative complication rates in women undergoing prepectoral tissue expander placement, despite the antibiotic group having higher baseline risk for complications. As a result, our current practice is to prescribe all patients undergoing immediate prepectoral tissue expander placement a one-week course of antibiotics.