MANAGEMENT OF SECONDARY HYPERFIBRINOLYSIS IN EXTRACORPOREAL MEMBRANE OXYGENATION AS IDENTIFIED BY THROMBOELASTOGRAPHY

Abstract

SESSION TITLE: Clinical Conundrums in ECMO SESSION TYPE: Fellow Case Reports PRESENTED ON: 10/20/2019 01:00 pm - 02:00 pm INTRODUCTION: Hemorrhagic and thrombotic complications are the leading cause of morbidity and mortality in patients on Extracorporeal Membrane Oxygenation (ECMO). Pinpointing the cause of hemostasis-related complications is very challenging. Identifying the etiology of the coagulopathy in a timely manner is crucial so as to be able to prevent fatal complications. We describe a group of six patients in which Thromboelastography (TEG) was utilized to identify secondary hyperfibrinolysis as the cause of bleeding. Establishing this diagnosis led to rapid changes in management with quick resolution of bleeding. CASE PRESENTATION: Six ECMO patients in the MICU at Banner University Medical Center-Phoenix, all at variable times during their ECMO run, suffered clinical hemorrhage. Four patients were anticoagulated with unfractionated heparin (UFH) while two were off anticoagulation completely. A TEG was obtained at time of bleeding and we observed elevated LY-30 levels greater than 7.5%, an indication of lysis. Upon identification of the fibrinolytic state, these patients were treated either by initiating anticoagulation or by switching anticoagulant class to a direct thrombin inhibitor. This decision was made with the understanding that the fibrinolysis was a manifestation of hypercoagulability secondary to intravascular or ECMO related clot that must be treated with anticoagulation, despite the clinical bleeding. With this approach, we observed resolution of hemorrhage as the anticoagulant was titrated to normalization of LY-30 levels targeting resolution of the underlying secondary hyperfibrinolysis. DISCUSSION: TEG has long been used in the Trauma and Surgical ICU’s however its use in the MICU, particularly in ECMO, is not yet common practice. Most ECMO centers use UFH as their anticoagulant of choice. Generally, aPTT is the standard assay used for monitoring UFH levels. As a value obtained from plasma however, aPTT may not reflect the coagulation cascade comprehensively. TEG, a test of whole blood, better allows for examination of platelet function and provides details regarding time to fibrin formation and clot lysis. This is of great utility in patients during ECMO given the complexity of coagulation disorders associated with it. CONCLUSIONS: After extensive literature review, we find this approach to be novel in that management of bleeding was targeted at the treatment of secondary hyperfibrinolysis during ECMO with the use of TEG. Further, blood product transfusions were minimized and inappropriate interruption in anticoagulation was avoided in a thrombus prone circuit. Anticoagulation is often reflexively decreased or discontinued when hemorrhage is observed. Given that secondary hyperfibrinolysis is truly a manifestation of systemic hypercoagulability and treated with anticoagulation, we find this final point to be of ultimate importance. Reference #1: Panigada M, Iapichino GE, Brioni M, Panrello G, Protti A, Grasselli G, Occhipinti GO, Novembrino C, Consonni D, Arcadipine A, Gattinoni L, Presenti, A. Thromboelastography-based anticoagulation management during extracorporeal membrane oxygenation: a safety and feasibility pilot study. Annals Intensive Care. 2018; 16;8(1):7. Reference #2: Mulder, M.M.G, Fawzy, G, Lance, M.D.ECMO and anticoagulation: a comprehensive review. Netherlands Journal of Critical Care. 2017; 26(1). Reference #3: Kreyer S, Muders T, Theuerkauf N, Spitzhuttl J, Schellhaas T, Schewe JC, Guenther U, Wrigge H, Putense C. Hemorrhage under veno-venous extracorporeal membrane oxygenation in acute respiratory distress syndrome patients: a retrospective data analysis. Journal of Thoracic Disease. 2017; 9(12): 5017–5029. DISCLOSURES: No relevant relationships by Thomas Ardiles, source=Web Response No relevant relationships by Sarika Savajiyani, source=Web Response