Challenge: Develop a portable pneumatic driver for a commercially available temporary total artificial heart that can be used in multiple clinical settings, including the OR, ICU and step-down unit. The new design would also provide patients an ambulatory option so they could convalesce at home. The heart driver needed to include a self-contained pneumatic source which was to perform identically to its predecessor, a large washing machine-sized console connected permanently to the hospital's air supply. The device needed to provide a wide range of pneumatic flow capacity for the heart to maintain more than 9 liters/minute pumping rate and integrate a Graphical User Interface that was resident on a separate monitoring computer. The design needed to retain the quality and reliability attributes for continuous life support and survive a multitude of user environments.
Concept: The NextPhase engineering team developed a portable drive unit that could be "hot swap" mounted into different transportation carts for diverse use environments with a 6-hour battery life. For hospital use, the drive unit would be installed in a convenient wheeled cart, with a large touch screen display, mains power supply, and storage compartments. For home or mobile use, the driver unit could be lifted out of the hospital cart and mounted in a portable caddy, similar to a luggage caddy. Finally, the driver could also be used as a stand-alone unit on a desktop.
To address the requirement that the unit be continuously functioning, even in the event of component failure, the design incorporated multiple layers of system redundancy and diversity. Also, the system employed sophisticated velocity algorithms for its redundant custom servo-controlled compressors mimicking the predicate system that relied on hospital air supply. The system incorporated several layers of "hot swappable" power sources that could be seamlessly switched including redundant external smart lithium batteries, AC main power, and emergency internal smart lithium batteries.
Solution: The entire completed product was designed, developed, validated and verified at NextPhase. After CE and FDA approvals were issued, the device was manufactured on our floor and NextPhase managed the preventive maintenance responsibilities in house, as well. Additional aftermarket services and shipping distribution were services NextPhase continually performed during this program. There were approximately 160 recipients of the total artificial heart systems in 2013.