Magnetic levitation motor for pediatric cardiac and cardiopulmonary therapies

Abstract
This Phase I STTR application proposes development of an innovative low cost magnetic levitation motor
specifically designed for pediatric extracorporeal cardiac and cardiopulmonary therapies Magnetic levitation
enables contact free impeller operation thereby eliminating critical areas of wear and heat generation that can
contribute to hemolysis and thrombosis The extracorporeal pediatric market is currently served by a single
magnetically levitated blood pump St Jude Medicalandapos s PediMag formerly Thoratec As with many pediatric
medical products the PediMag is a scaled down version of a prior adult device originally designed for post
cardiotomy support CentriMag While PediMag has been used successfully in a range of post cardiotomy
support applications broader usage is complicated by several factors including lack of ancillary componentry
designed specifically for the pump system e g pediatric blood oxygenator and heat exchanger complex
control algorithms and a high disposable cost approximately $ per disposable PediMag pump head To
address these shortcomings we propose an innovative magnetic levitation system based on a hysteresis
motor concept that permits a smaller overall configuration eliminates magnetic field safety concerns reduces
vibration and relocates the costly rare earth magnetic elements from the disposable blood contacting
component to the reusable motor stator The hysteresis motor design also permits simplified control
algorithms for enhanced robustness and reduced power requirements enhancing patient transport and
mobility The rotor impeller portion of the proposed hysteresis motor will be based on the same impeller
geometry as is currently used in the existing pCAS pump oxygenator replacing the current mechanical
bearings rotating shaft and blood contacting seal This strategy will lower overall development costs and
permit the use of existing comprehensive in vitro and in vivo test data to allow direct and efficient comparison
of the performance of the new magnetically levitated prototype to the existing blood seal based pCAS pump
oxygenator In Phase I we will perform two acute and one day chronic animal study This permits us to
demonstrate basic feasibility while simultaneously minimizing costs and the Phase I project timeline However
as part of a subsequent Phase II effort we plan to significantly expand our chronic in vivo studies to include
multiple evaluations of at least days
!Narrative
Many pediatric medical products are simply scaled down versions of adult products Currently the only
magnetically levitated blood pump available for pediatric support is similarly a scaled down version of its adult
counterpart This project intends to develop improved technology specifically for the pediatric cardiac and
cardiopulmonary life support patient populations and test it using an integrated pump oxygenator