The Pulsatile Modification Improves Hemodynamics and Attenuates Inflammatory Responses in Extracorporeal Membrane Oxygenation

Background: COVID-19 is still a worldwide pandemic and extracorporeal membrane oxygenation (ECMO) is vital for extremely critical COVID-19 patients Pulsatile flow impacts greatly on organ function and microcirculation, however, the effects of pulsatile flow on hemodynamics and inflammatory responses during ECMO are unknown An in vivo study was launched aiming at comparing the two perfusion modes in ECMO Methods: Fourteen beagles were randomly allocated into two groups: the pulsatile group (n=7) and the non-pulsatile group (n=7) ECMO was conducted using the i-Cor system for 24 hours Hemodynamic parameters including surplus hemodynamic energy (SHE), energy equivalent pressure (EEP), oxygenator pressure drop (OPD), and circuit pressure drop (CPD) were monitored To assess inflammatory responses during ECMO, levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-8, and transforming growth factor-beta1 (TGF-beta1) were measured Results: EEP and SHE were markedly higher in pulsatile circuits when compared with the conventional circuits Between-group differences in both OPD and CPD reached statistical significance Significant decreases in TNF-alpha were seen in animals treated with pulsatile flows at 2 hours, 12 hours, and 24 hours as well as a decrease in IL-1beta at 24 hours during ECMO The TGF-beta1 levels were significantly higher in pulsatile circuits from 2 hours to 24 hours The changes in IL-6 and IL-8 levels were insignificant Conclusion: The modification of pulsatility in ECMO generates more hemodynamic energies and attenuates inflammatory responses as compared to the conventional non-pulsatile ECMO