Reversing flow blood processing system having reduced clotting potential

A tubular set portion for use with a complete tubular arrangement for the extracorporeal treatment of blood, which set portion comprises:

• A flow reversing valve;
• A patient arterial line and a patient venous line, each separately connected to one side of said valve;
• A unit arterial line and a unit venous line, each separately connected to another side of said valve;
• Said patient arterial line connected with the unit arterial line in a first position of said valve and said patient venous line connected with the unit venous line in said first position of said valve.
• Said patient arterial line connected with the unit venous line in a second position of said valve;
• and said patient venous line connected with the unit arterial line in said second position of the valve;
• Said flow reversing valve being moveable between said first and second positions by relative rotation of part of the valve and adjacent portions of the patient arterial and venous lines with respect to the unit arterial and venous lines, said flow reversing valve carrying first and second engaging plates, said first plate having a first pair of ports that respectively connect to the patient arterial and venous lines, the second plate having a second pair of ports that respectively connect to the unit arterial and venous lines, said first and second plates being relatively rotatable and sealed at a surface, whereby either port of said first pair can communicate with either port of the second pair at differing rotatable positions respectively corresponding to said first and second positions;
• and a stop member carried on each of said plates peripherally outside of said unit and patient arterial and venous lines to limit movement of said plates to a rotational range between and including said first and second positions;
• said lines each having ends opposed to said flow reversing valve that carry connectors for connection to other portions of said complete tubular arrangements.

The method of performing an extracorporeal treatment of blood, which comprises the steps of:

• (1) drawing blood from a patient through a patient arterial line and passing said blood from the patient arterial line to a unit arterial line through a moveable valve with straight, laminar flow;
• passing blood from the unit arterial line to a blood processing unit;
• passing blood from the blood processing unit to a unit venous line;
• passing blood from the unit venous line to a patient venous line through said moveable valve with straight, laminar flow, and from there back to the patient, said process further including the step of (2) switching the connections of said line without external disconnection and reconnection, said switching being accomplished by moving said valve between first and second flow-permitting positions in which, during said switching of the connection of said lines, said valve is moved through a flow-blocking zone to block flow through said valve;
• and, thereafter, (3) passing blood from the patient through the patient venous line and then through said valve with straight, laminar flow to the unit arterial line;
• passing blood from the unit arterial line through the connected blood processing unit to the unit venous line;
• passing blood from the unit venous line through the valve with straight, laminar flow to the patient arterial line, and returning blood from the patient arterial line to the patient.

A tubular set portion for use with a complete tubular arrangement for the extracorporeal treatment of blood, which set portion comprises:

• a flow reversing valve;
• a patient arterial line and a patient venous line, each separately connected to one side of said valve;
• a unit arterial line and unit venous line, each separately connected to another side of said valve;
• said patient arterial line connected with the unit arterial line in the first position of said valve and said patient venous line connected with the unit venous line in said first position of said valve;
• said patient arterial line connected with the unit venous line in a second position of said valve and said patient venous line connected with the unit arterial line in said second position of the valve;
• said flow reversing valve being movable between said first and second positions by relative rotation of part of the valve and adjacent portions of the patient arterial and venous lines with respect to the unit arterial and venous lines;
• in which said flow reversing valve carries first and second engaging plates, said first plate having a first pair of ports that respectively engage the patient arterial and venous lines, the second plate having a second pair of ports that respectively engage the unit arterial and venous lines, said first and second plates being relatively rotatable and peripherally sealed, whereby either port of said first pair can communicate with either port of the second pair at differing rotatable positions respectively corresponding to said first and second positions, and further in which a sealing plate is positioned between said first and second plates, and connected to one of said first and second plates, said sealing plate having a pair of apertures that register with one of said pairs of ports, said sealing plate firmly engaging the other of said plates with a seal surface.

A tubular set portion for use with a complete tubular arrangement for the extracorporeal treatment of blood, which set portion comprises:

• a flow reversing valve;
• a patient arterial line and a patient venous line, each separately connected to one side of said valve;
• a unit arterial line and a unit venous line, each separately connected to another side of said valves;
• said patient arterial line connected with the unit arterial line in a first position of said valve and the patient venous line connected with the unit venous line in said first position of said valve;
• said patient arterial line connected with the unit venous line in a second position of said valve and said patient venous line connected with the unit arterial line in said second position of the valve;
• said flow reversing valve being movable between said first and second positions by relative rotation of part of the valve and adjacent portions of the patient arterial and venous lines with respect to the unit arterial and venous lines;
• further in which a locking member is provided to retain said valve either in said first position or said second position.