Seal‐less Centrifugal Blood Pump with Magnetically Suspended Rotor: Rot‐a‐Flot

Abstract

Limitations of current centrifugal blood pumps are related to heat generation of bearings and leakage of seals, to dead water zones, and to poor efficiency. A new concept is proposed in this paper to ameliorate these problems based on a miniaturized magnetic drive, and a prototype is introduced. The pump rotor is suspended and driven by a radial permanent magnetic field that stabilizes the impeller in 4 of the 6 spatial degrees of freedom and allows it to be top-spun on a single blood-flushed pivot bearing with minimal load and friction. A shrouded impeller with an open center and 4 logarithmically curved channels is run inside a cone-and-plate-type housing with a spiral volute chamber. In vitro testing was performed comparing this design with the BioMedicus, St. Jude, and Sarns pumps. The prototype is demonstrated to have the smallest internal volume (35 ml), surface (190 qcm), and passage time (0.5 s at 4 L/min), as well as the highest hydraulic efficiency (up to 0.4) of all devices studied.

Left heart bypass support with the Rotaflow Centrifugal Pump® as a bridge to decision and recovery in an adult

“…The bearing is washed out via blood flow because this centrifugal pump has an impeller with an open center. For this reason, it only infrequently develops functional problems because of thrombus formation around the bearing [4]. The volume capacity of the Rotaflow centrifugal pump Ò is 32 ml.…”

Extracorporeal life support: Updates and controversies

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Contemporary extracorporeal membrane oxygenation for adult respiratory failure: life support in the new era

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