An air embolism protection system for extracorporeal circuits using centrifugal pumps

A system was developed to detect air bubbles in extracorporeal fluid circuits and to automatically occlude the tubing to prevent propagating the potentially fatal air volume. A Zevex ultrasonic air-detector was integrated into a device that used two parallel coupled AC-solenoids to mechanically clamp the extracorporeal fluid line. The device is capable of detecting bubbles 100 /spl mu/l in size and to clamp lines with an outer diameter of 1/2 inch. The intended application is during extracorporeal perfusion using centrifugal pumps, which have no inherent air-embolism protection.