0060An Investigation of the Correlation Between Ultrafiltration and Postoperative Thrombocytopenia: A Retrospective Cohort Study

Background Thrombocytopenia following cardiac surgery is common, and its association with increased morbidity and mortality in cardiac surgery patients is well established. Interventions that impact platelet function or concentration therefore warrant significant attention and detailed analysis. Ultrafiltration (UF) is commonly utilized to counteract hemodilution and remove inflammatory mediators while on cardiopulmonary bypass (CPB), and while designed to retain blood products, its specific interaction with platelets and ability to adequately maintain platelet concentrations have not been thoroughly investigated or characterized. Methods This single center retrospective cohort study stratified males aged 55-70 undergoing non-emergent coronary artery bypass grafting and mitral or aortic valve repair or replacement with use of CPB between 2022-2025 into UF and non-UF (NUF) groups. Primary outcomes of post operative platelet count and intraoperative platelet transfusion rate, and secondary outcomes of 30-day platelet nadir and 30-day mortality were compared using univariate and multivariate analyses. Results 255 patients were included (81 UF, 174 NUF). There was no intergroup difference in pre operative platelet count, weight or estimated blood volume. There was no difference in post operative platelet count (median 124 vs 126, p=0.690), but UF transfusion rate was significantly higher (51.9% vs 30.5% of cases, median 250 vs 0, p=0.0004). UF 30-day platelet nadir was significantly lower (median 101 vs 111, p=0.035), and no mortality difference was observed (5 vs 5, p=0.297). Conclusions UF is associated with significantly higher platelet transfusion requirements during cardiac surgery cases utilizing CPB, challenging previously held notions regarding UF impact on blood product hemoconcentration. Is this an encore abstract? No