Effect of Modified Ultrafiltration on Whole Blood Coagulation in Cardiac Surgery With Cardiopulmonary Bypass: Retrospective Analysis

In cardiac surgery patients, ultrafiltration (UF) was applied to reduce free water and concentrate all blood components during cardiopulmonary bypass (CPB). Concentrating plasma substrate of UF would be beneficial in attenuating CPB-induced dilutional coagulopathy. This study was to investigate whether MUF affected viscoelastic profiles during CPB for cardiac surgery.

Patients who underwent elective cardiac surgery and MUF at the end of CPB during January 2019-December 2021 are recruited. Using the patients' electronic medical records, the values of maximum clot firmness of EXTEM assay (MCF-EXTEM) of rotational thromboelastometry (ROTEM) test before and after applying MUF are retrospectively analyzed.

As the primary measure, we determine the changes of MCF-EXTEM after applying MUF. With an assumption that MUF increased MCF-EXTEM, the receiver operating characteristic (ROC) analysis is applied to MCF-EXTEM change. The area under the ROC curve is determined and the cut-off value is estimated with specificity and sensitivity in Youden's J statistics. The change of MCF-EXTEM in patients who show MCF-EXTEM less than the cut-off value is analyzed. The changes of hematocrit (Hct) before and after applying MUF is also determined.