Coagulation disorders in subjects undergoing pump-driven veno- venous ECCO2-R for severe acute hypercapnic respiratory failure - a single center experience

Introduction: Recent evidence suggests low-flow extracorporeal CO2 removal (ECCO2-R) systems as safe and promising adjunctive therapy to avoid endotracheal intubation and the related negative consequences in subjects with severe hypercapnic respiratory failure [1]. In high-flow extracorporeal membrane oxygenation systems heterogeneous coagulation disorders are a well-known complication. However, to date there is little evidence for the influence of pump-driven low-flow veno-venous ECCO2-R on the coagulation system.
Objectives: This study is a retrospective analysis of four subjects developing coagulation disorders with bleeding complications while undergoing ECCO2-R.
Methods: Four subjects treated with a pump-driven veno-venous ECCO2- R (system: iLA Activve®; membrane ventilator: Minilung®; Novalung GmbH, Talheim, Germany) for severe hypercapnic respiratory failure due to acute exacerbation of COPD were included in this study. Unfractionated heparin was used for anticoagulation with a target aPTT of 45-55 sec. Coagulation parameters i.e. hemoglobin, platelets, fibrinogen, antithrombin and D- DIMER were retrieved from the charts at treatment initiation and during the time range starting 72 hours before and ending at the clinical onset of the bleeding complication.
Results: Mean application time of ECCO2-R was 196.5 h ( ± 77.4) with an average blood flow of 1.1 l/min ( ± 0.2). Bleeding events consisted of two pulmonary bleedings, one large soft tissue hematoma and one hemothorax. Coagulation parameters are depicted below in Table 1. ECCO2-R was removed in all subjects after onset of the bleeding complication resulting in stabilization of the coagulation state. Conclusions: Despite adequate anticoagulation subjects undergoing pump-driven veno-venous ECCO2-R developed coagulation disorders similar to disseminated intravascular coagulation with concomitant bleeding complications. The underlying mechanism remains to be clarified.