Ultrafiltration in cardiac surgery: Results of a systematic review and meta-analysis
Nadia B. Hensley, Joseph Colao, Andrés Zorrilla‐Vaca, Julie Nanavati, Jennifer S. Lawton, Jacob Raphael, Michael Mazzeffi, Chad Wierschke, Megan P. Kostibas, Brian C. Cho, Steven M. Frank, Michael C. Grant
Abstract
Background: Ultrafiltration is used with cardiopulmonary bypass to reduce the effects of hemodilution and restore electrolyte balance. We performed a systematic review and meta-analysis to analyze the effect of conventional and modified ultrafiltration on intraoperative blood transfusion. Methods: Utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement, we systematically searched MEDLINE, EMBASE, Web of Science, and Cochrane Library to perform a meta-analysis of studies of randomized controlled trials (RCTs) and observational studies evaluating conventional ultrafiltration (CUF) and modified ultrafiltration (MUF) on the primary outcome of intraoperative red cell transfusions. Results: A total of 7 RCTs ( n = 928) were included, comparing modified ultrafiltration ( n = 473 patients) to controls ( n = 455 patients) and 2 observational studies ( n = 47,007), comparing conventional ultrafiltration ( n = 21,748) to controls ( n = 25,427). Overall, MUF was associated with transfusion of fewer intraoperative red cell units per patient ( n = 7); MD −0.73 units; 95% CI −1.12 to −0.35 p = 0.04; p for heterogeneity = 0.0001, I 2 = 55%) compared to controls. CUF was no difference in intraoperative red cell transfusions compared to controls ( n = 2); OR 3.09; 95% CI 0.26–36.59; p = 0.37; p for heterogeneity = 0.94, I 2 = 0%. Review of the included observational studies revealed an association between larger volumes (>2.2 L in a 70 kg patient) of CUF and risk of acute kidney injury (AKI). Conclusion: The results of this systematic review and meta-analysis suggest that MUF is associated with fewer intraoperative red cell transfusions. Based on limited studies, CUF does not appear to be associated with a difference in intraoperative red cell transfusion.