Perioperative Antibiotics Do Not Reduce Surgical Site Infections After Fat Grafting for Breast Reconstruction

BACKGROUND: Fat grafting is commonly utilized to enhance outcomes in breast reconstruction. Despite their routine implementation, perioperative antibiotics lack sufficient evidence in reducing rates of surgical site infection (SSI). Leveraging the largest patient cohort to date, this study examines the association between perioperative antibiotics and SSI after fat grafting for breast reconstruction. METHODS: The Epic Cosmos database (Verona, Wisconsin) was queried for patients who underwent fat grafting within one year following either implant-based or autologous breast reconstruction from January 2017 to January 2025. SSIs within 30 days were identified using either International Classification of Diseases (ICD) codes or identification of a new antibiotic prescription starting >7 days post-surgery. Perioperative antibiotics, age, body mass index (BMI), diabetes, smoking status, intraoperative intravenous antibiotics, and volume of fat grafted were included for multivariable regression. RESULTS: We analyzed 12,247 fat grafting procedures (8416 implant-based, 3831 autologous). In the implant-based cohort, perioperative antibiotics (OR, 1.21; P = 0.031), diabetes (OR, 1.65; P < 0.0001), higher BMI (OR, 1.02; P = 0.001), and younger age (OR, 0.99; P = 0.021) were significant risk factors for infection, defined by additional postoperative antibiotic prescriptions. For infections defined by ICD codes, only BMI was significantly associated with SSI (OR, 1.04; P = 0.001). In the autologous cohort, diabetes was the only significant risk factor for SSI (OR, 1.3; P = 0.033). CONCLUSION: Perioperative antibiotic prescriptions do not decrease SSI after fat grafting in either implant or autologous breast reconstruction patients. However, they are associated with increased additional postoperative antibiotic prescriptions in implant-based breast reconstruction patients. These data suggest reconsidering routine perioperative antibiotic prophylaxis and focusing on patient-specific risk factors.