Is Extracorporeal CO2 Removal Really "Safe" and "Less" Invasive? Observation of Blood Injury and Coagulation Impairment during ECCO2R.

Abstract

Extracorporeal CO2 removal (ECCO2R) is promoted with attributes like "safe" and "less invasive" compared with (high-flow) venovenous extracorporeal membrane oxygenation (ECMO) systems. With our experience in coagulation disorders during ECMO therapy with this observational study, we for the first time prospectively evaluate hemolysis and coagulation disorders during ECCO2R. Eight consecutive patients with predominant hypercapnic respiratory failure were treated with the Hemolung respiratory assist system (Alung-Technologies, Pittsburg, PA). Bleeding as well as changes of coagulation parameters was prospectively assessed. Overall therapy was observed in seven patients with 52 treatment days. In four of seven patients (57%), relevant clinical bleeding symptoms occurred. Thrombocytopenia, hemolysis, factor XIII deficiency and acquired von Willebrand syndrome (loss of high-molecular-weight von Willebrand factor multimers) were typical findings, and the patients spontaneously recovered after discontinuation of the extracorporeal system. In one patient, extracorporeal system stopped because of thrombotic occlusion. Six of seven patients required transfusion of red blood cells. Our observation shows that even low-flow extracorporeal lung support is associated with relevant clinical bleeding symptoms, blood cell injury, development of acquired von Willebrand syndrome and need for transfusion. In our opinion, it therefore is too early to quote ECCO2R "safe" and "less invasive."