https://www.selleckchem.com/products/ademetionine.html ively. Differences in hematoma volume (330 vs 169.3 mL, P = 0.078) and reconstructive failure (33.3% vs 5%, P = 0.057) approached significance between both groups. CONCLUSIONS Hematoma after TE-IBR should be monitored closely, as it may play a role in jeopardizing reconstruction success. Patients on home antithrombotic medication may be at increased risk of larger-volume hematomas and reconstruction failure. Plastic surgeons should consider aggressive surgical evacuation of postoperative TE-IBR hematomas to reduce subsequent complications and reoperations, thus optimizing reconstructive outcomes.BACKGROUND Acellular dermal matrix (ADM) is commonly used during immediate expander-based breast reconstruction, with potential advantages of greater intraoperative expansion, decreased time to complete expansion, and decreased rates of capsular contracture. However, ADM is associated with increased infection rate, seroma, and subsequent reconstructive failure. Poly-4-hydroxybutyric acid (P4HB) mesh is a large pore, biosynthetic scaffold shown to fully resorb and incorporate host tissues within 18 months. We sought to compare outcomes between the use of P4HB and ADM in immediate retropectoral expander-based reconstruction. METHODS One hundred ninety-two consecutive cases (107 patients) of breast reconstruction using ADM were compared with a subsequent cohort of 112 cases (62 patients) using P4HB mesh. In all patients, reconstruction was performed immediately after mastectomy by a single surgeon, and outcomes were compared between groups. RESULTS Baseline characteristics were similar between the P4HB and ADM groups. Overall infection rates were lower, but not significantly with P4HB (11% vs 17%, P = 0.18). Time to drain removal was significantly lower with P4HB (15 vs 18 days, P = 0.008), although there was no difference in rates of seroma (0.9% vs 3%, P = 0.43). Similar numbers of patients underwent external beam radiati