Impact of Intraoperative Vasopressors on DIEP Flap Reconstruction After Radiation Therapy

Introduction: The Deep Inferior Epigastric Perforator (DIEP) flap is widely used for autologous breast reconstruction given its minimal donor site morbidity. However, debate exists regarding intraoperative vasopressor use, particularly in patients who received radiation therapy. This study aims to determine the impact of intraoperative vasopressors on postoperative outcomes in patients undergoing DIEP flap reconstruction, focusing on the irradiated high-risk population. Methods: A retrospective review of patients with stage I-III breast cancer who underwent DIEP flap breast reconstruction from 2023-2024 at a single quaternary-referral center was performed. Primary outcomes included postoperative complications. Secondary outcomes include flap loss rates. Subgroup analysis was performed for patients who received adjuvant radiation therapy. Results: Of 217 patients, 340 DIEP flaps were analyzed. Mean age was 50 years (IQR 43-56) and BMI 28.5±3.8. Half of the cohort received radiation therapy (50.3%, n=171). Vasopressors were administered intraoperatively in 16% (n=55) of cases. The overall complication rate was 19%. Breast wound dehiscence rates were 6%, fat necrosis 8%, partial flap loss 5%, and complete flap loss <1%. Postoperative transfusion was an independent predictor of flap loss (OR 4.00, 95% CI 1.06–15.1, p=0.04). For patients who received radiation therapy, revision of venous anastomosis (OR 8.25, CI 1.19–57.0, p=0.03), revision of arterial anastomosis (OR 6.25, CI 1.16–7.45, p=0.04), and prior hormone therapy (OR 6.54, CI 1.46–29.3, p=0.01) was associated with flap loss. When accounting for relevant clinicopathologic factors, intraoperative vasopressor use was not associated with increased postoperative complications in either the overall cohort or radiation therapy subgroup (all p>0.05). Conclusion: Intraoperative vasopressors appear safe in DIEP flap reconstruction, even in patients who receive radiation therapy. However, among irradiated patients, intraoperative vasopressors may increase the likelihood for anastomotic revisions. These findings underscore the importance of patient selection and anticipatory surgical planning, enabling more effective counseling and operative strategies for challenging cases.