Risk factors and timing of postoperative hematomas following microvascular breast reconstruction: A prospective cohort study

BACKGROUND Microvascular free tissue transfer has become the gold standard for breast reconstruction. While safe and reliable, there are operative complications, with hematomas developing under the free flap among the more common. These can compromise flap viability, lead to hemodynamic instability and infection. This study aims to identify predictors of hematomas following free-flap breast reconstruction. METHODS A prospective study was undertaken of patients undergoing autologous free-flap breast reconstruction over a 4-year period. Precise times to hematoma formation, age, arterial and venous anastomosis time, and anastomosis length were recorded and analyzed for association with time to hematoma formation. RESULTS One thousand two hundred twelve flaps were undertaken in 1,070 patients during the period of review. Seventy-one (5.8%) flaps were taken back to theater for hematomas. Immediate reconstruction had a significantly higher hematoma rate compared to delayed reconstruction 7.4% versus 5.2% (p