Blood processing method and apparatus with disposable cassette

A blood-processing apparatus for providing failsafe control of fluid transfer between a primary tube and a plurality of secondary tubes with which the primary tube is in fluid communication, the apparatus comprising:

• a cassette to which the secondary tubes are mounted, a first manifold coupling each secondary tube to the primary tube and a second manifold coupling another tube to the primary tube, each secondary tube being mounted adjacent a closing surface;
• a working surface to which the cassette is removably secured;
• a plurality of pinch valves each of which controls occlusion of one of the secondary tubes, the pinch valves being biased in a normally-closed position such that with the cassette secured to the working surface, each pinch valve compresses a secondary tube against a closing surface to restrict fluid flow therethrough;
• a movable handle which, when closed, causes the cassette to be secured to the working surface;
• a base plate to which the pinch valves are mounted;
• a lifting mechanism linking motion of the base plate in a direction perpendicular to the plane of the working surface to motion of the handle, closing of the handle moving the base plate closer to the working surface such that the pinch valves extend through spaces in the working surface to engage the secondary tubes of the cassette mounted to the working surface;
• and
• a locking mechanism which, if locked when the handle is in a closed position, restricts the motion of the handle and the lifting mechanism to prevent motion of the handle away from the closed position while the blood-processing apparatus is being operated;
• and
• a fluid sensor for monitoring the presence of fluid in the second manifold.

A disposable assembly for use with an apparatus which regulates the flow of biological fluids, the assembly comprising:

• a first tube;
• a plurality of secondary tubes;
• an interconnection manifold for providing fluid communication between the first tube and the secondary tubes;
• a plurality of fluid containers, each in fluid communication with a separate one of the secondary tubes;
• and
• a flat radiation coupling surface formed on the exterior of the manifold for coupling radiation from an external transducer into the interior of the manifold to sense the presence of fluids therein.

Apparatus for a disposable cassette in which a rigid fluid manifold is provided for interconnecting a first flexible conduit to a second flexible conduit comprising:

• a) a planar deck for supporting said cassette in a horizontal position;
• b) a base plate depending from the deck and adapted for vertical movement from a lower plane position to an upper plane position parallel to said planar deck;
• and
• c) a fluid detector affixed to said base plate opposite an opening in said deck adjacent said manifold;
• such that when said base plate is in said upper plane position the detector is in intimate contact with a surface of the manifold.

A blood processing system comprising:

• a) a first flexible fluid communication tube coupled on one side to a rigid fluid manifold and on another side to a blood processing centrifuge in which blood fluid is separated into constituent component fluids, some of which are coupled by said tube to said manifold;
• b) said manifold having an external flat sonic coupling surface;
• and
• c) an external transducer for coupling sonic radiation into and out of the manifold through the coupling surface for sensing the presence of fluid in the manifold.