Hemostatic Complications During Neonatal Extracorporeal Membrane Oxygenation: Roller Pump and Centrifugal Pump Driven Circuits

Abstract

Recently three different neonatal extracorporeal membrane oxygenation (ECMO) circuits have been employed in our clinic. These circuits were compared for clotting and bleeding complications. Initially, we used an ECMO circuit containing a roller pump and venous bladder without severe complications. Manufacturing of circuit components was discontinued, necessitating the replacement of this circuit by a circuit with a centrifugal pump with 3/8 inch inlet and outlet. Acute increase of oxygenator resistance requiring emergency changeout became unexpectedly a regularly occurring complication. The increase in resistance was suspected to be caused by oxygenator clotting, although oxygenator function was preserved. To prevent this complication, we changed to a levitating centrifugal pump with 1/4 inch inlet and outlet, after which no oxygenator malfunction has been observed. Macroscopic and electron microscopic analysis demonstrates that small clots are formed within the circuit, presumably in or near the centrifugal pump, which are transported to the oxygenator and clog up the hollow fiber layer at the inlet side, barely penetrating the oxygenator beyond this first layer. Our results suggest that low blood velocities accompanied with recirculation of blood within or near the centrifugal pump and/or heat generation within the pump could contribute to the formation of these clots.

Response to Hemostatic Complications During Neonatal Extracorporeal Membrane Oxygenation: Roller Pump and Centrifugal Pump Driven Circuits

“…Vermeer et al . 1 have now provided in vivo evidence for the in silico and in vitro data provided by Schöps et al . 3…”

“…Consequently, blood remains in the pump shear field for an extended time, significantly increasing the risk for hemolysis, which was demonstrated in vitro. Vermeer et al 1 have now provided in vivo evidence for the in silico and in vitro data provided by Schöps et al 3 However, we believe there is still more to the story. Several other factors are likely at play in neonatal ECLS, including cellular fragility 4 and hemoglobin greater than 12-13 g/dl, which has been shown to be an independent factor leading to blood damage for neonatal ECLS regardless of pump type.…”

“…Vermeer et al . 1 recently published a case series and in vitro analysis of acute oxygenator failure manifested as a rise in preoxygenator pressure without evidence of gas transfer failure. As practitioners in the field who have fielded similar questions from colleagues describing similar issues, we applaud them for describing this problem that has been informally discussed in meetings and discussion boards for several years.…”

“…Vermeer et al . 1 began using the RotaFlow in neonatal ECLS because of supply shortages and the availability and experience with adult ECLS. After a disturbing trend of complications, they embarked on a formal assessment of three systems (roller pump, RotaFlow, and PedIVAS) and associated failure rates in the neonatal population.…”

What’s new in neonatal and pediatric extracorporeal membrane oxygenation in 2022–2023? Insights from the EuroELSO congress 2023

“…increase of oxygenator resistance due to clotting). 23 However, the shift to the newer neonatal and pediatric magnetically suspended centrifugal pumps reduced this risk. In a single center retrospective study, Vermeer H. et al 23 described that when adult centrifugal pumps were used in children, recirculation and blood stagnation within the centrifugal pump increased the risk of clotting inside the pump and into the oxygenator.…”