Microvesicles Are Associated with Early Veno Venous ECMO Circuit Change during Severe ARDS: A Prospective Observational Pilot Study.

BACKGROUND: Veno venous Extra Corporeal Membrane Oxygenation (vvECMO) is associated with frequent hematological ECMO-related complications needing ECMO circuit change. Microvesicles (MVs) interplay during the thrombosis-fibrinolysis process. The main objective of the study was to identify subpopulations of MVs associated with indications of early vvECMO circuit change.

METHODS: This is a prospective observational monocenter cohort study. Blood gas was sampled on the ECMO circuit after the membrane oxygenator to measure the PO2 post oxy at inclusion, day 3, day 7 and the day of ECMO circuit removal. Blood samples for MV analysis were collected at inclusion, day 3, day 7 and the day of ECMO circuit removal. MV subpopulations were identified by flow cytometry.

RESULTS: Nineteen patients were investigated. Seven patients (37%) needed an ECMO circuit change for hemolysis (n = 4), a pump thrombosis with fibrinolysis (n = 1), persistent thrombocytopenia with bleeding (n = 1) and a decrease of O2 transfer (n = 1). Levels of leukocyte and endothelial MVs were significantly higher at inclusion for patients who thereafter had an ECMO circuit change ( p = 0.01 and p = 0.001). The areas under the received operating characteristics curves for LeuMVs and EndoMVs sampled the day of cannulation and the need for ECMO circuit change were 0.84 and 0.92, respectively. PO2 post oxy did not significantly change except for in one patient during the ECMO run.

CONCLUSIONS: Our pilot study supports the potential interest of subpopulations of microvesicles early associated with hematological ECMO-related complications. Our results warrant further studies.