Evaluation of a new magnetically suspended centrifugal neonatal pump in healthy animals using a veno-venous extracorporeal membrane oxygenation configuration.

Abstract

The objective of this animal study was to evaluate the hemodynamic performance of a new centrifugal pump for extra-corporeal membrane oxygenation (ECMO) support in neonates. Six healthy swines were supported with veno-venous ECMO with the New Born ECMOLife centrifugal pump (Eurosets, Medolla, Italy) at different flow rates: 0.25, 0.5, 0.6, and 0.8L/min; three animals were evaluated at low-flows (0.25 and 0.5L/min) and three at high-flows (0.6 and 0.8L/min). Each flow was maintained for 4hours. Blood samples were collected at different time-points. Hematological and biochemical parameters and ECMO parameters [flow, revolutions per minute (RPM), drainage pressure, and the oxygenator pressure drop] were evaluated. The increase of the pump flow from 0.25 to 0.5L/min or from 0.6 to 0.8 L/min required significantly higher RPM and produced significantly higher pump pressures [from 0.25 to 0.5L/min: 1470 (1253-1569) versus 2652 (2589-2750) RPM and 40 (26-57) versus 125 (113-139) mmHg, respectively; p < .0001 for both - from 0.60 to 0.8L/min: 1950 (1901-2271) versus 2428 (2400-2518) RPM and 66 (62-86) versus 106 (101-113) mmHg, respectively; p < .0001 for both]. Median drainage pressure significantly decreased from -18 (-22; -16) mmHg to -55 (-63; -48) mmHg when the pump flow was increased from 0.25 to 0.5L/min (p < .0001). When pump flow increased from 0.6 to 0.8L/min, drainage pressure decreased from -32 (-39; -24) mmHg to -50 (-52; -43) mmHg, (p < .0001). Compared to pre-ECMO values, the median levels of lactate dehydrogenase, d-dimer, hematocrit, and platelet count decreased after ECMO start at all flow rates, probably due to hemodilution. Plasma-free hemoglobin, instead, showed a modest increase compared to pre-ECMO values during all experiments at different pump flow rates. However, these changes were not clinically relevant. In this animal study, the "New Born ECMOLife" centrifugal pump showed good hemodynamic performance. Long-term studies are needed to evaluate biocompatibility of this new ECMO pump.