LAUSR

BACKGROUND Deep inferior epigastric perforator (DIEP) flaps are the gold-standard for autologous breast reconstruction. This study investigated risk factors for DIEP complications in a large, contemporary cohort to optimize surgical evaluation and planning. METHODS This retrospective study included patients who underwent DIEP breast reconstruction between 2016-2020 at an academic institution. Demographics, treatment, and outcomes were evaluated in univariable and multivariable regression models for postoperative complications. RESULTS In total, 802 DIEP flaps were performed in 524 patients (mean age 51.2±9.6, mean BMI 29.3±4.5). Most (87%) patients had breast cancer, and 15% were BRCA-positive. There were 282 (53%) delayed and 242 (46%) immediate reconstructions, and 278 (53%) bilateral and 246 (47%) unilateral reconstructions. Overall complications occurred in 81 (15.5%) patients, including venous congestion (3.4%), breast hematoma (3.6%), infection (3.6%), partial flap loss (3.2%), total flap loss (2.3%), and arterial thrombosis (1.3%). Longer operative time was significantly associated with bilateral immediate reconstructions and higher BMI. Prolonged operative time (OR=1.16, p=0.001) and immediate reconstruction (OR=1.92, p=0.013) were significant predictors of overall complications. Partial flap loss was associated with bilateral immediate reconstructions, higher BMI, current smoking status, and longer operative time. CONCLUSIONS Prolonged operative time is a significant risk factor for overall complications and partial flap loss in DIEP breast reconstruction. For each additional hour of surgical time, the risk of developing overall complications increases by 16%. These findings suggest that reducing operative time through co-surgeon approaches, consistency in surgical teams, and counseling patients with more risk factors towards delayed reconstructions may mitigate complications.