Diaphragm pressure pod for medical fluids

A tubular blood flow set which comprises a pressure sensing pod defining chamber, said pod being connected in flow-through relation to blood flow tubing of said set, said set defining a length of pressure tubing connected at one end with said chamber, for connection with a pressure sensing device at the other pressure tubing end, and a flexible diaphragm sealingly mounted within said pod between connections of said blood flow tubing and said pressure tubing, said diaphragm being moveable between first and second positions, the diaphragm in said first position bowing outwardly to substantially maximize volume in said chamber that communicates with said blood flow tubing, the diaphragm in said second position bowing inwardly to substantially minimize but not eliminate the volume in said chamber that is inside of said diaphragm, said diaphragm in use being in contact on one side thereof with flowing blood.

The method of rinsing blood from an extracorporeal blood flow tube and returning it to the patient after an extracorporeal blood flow procedure, said blood flow tubing connected to a chamber having a flexible diaphragm defining a blood holding volume, said diaphragm being sealingly mounted within said chamber, which method comprises:

• pressurizing said chamber to move said diaphragm to cause the blood holding volume of said chamber to be substantially minimized, without blocking flow through said blood flow tube and chamber;
• and causing aqueous solution to pass into said tube and chamber to replace said blood, while returning said blood to the patient.

A pressure sensing pod for a tubular medical fluid flow set which connects in flow-through relation to fluid flow tubing of said set, said pressure sensing pod defining a chamber having a movable, flexible, impermeable diaphragm dividing the chamber into two separate compartments, the fluid flow tubing communicating with one of said compartments and being isolated from the other of said compartments, a port carried on said pod, said port having a seal therein, said port communicating with the other of said compartments, whereby said other of said compartments is hermetically sealed until said port is opened for connection with a pressure measuring device, to keep the flexible diaphragm in a desired, initial position prior to opening of said seal.

A sealed port carried on a medical device, said port having a lumen which is sealed by a partition having a peripheral connection with a wall of said lumen;

• a major portion of the peripheral connection being relatively thin to be broken open;
• a minor portion of said peripheral connection being thicker than the major portion, to function as a hinge;
• a first section of said partition adjacent to said major portion being thicker than a corresponding, opposite section of said partition adjacent to the periphery of said minor portion, to focus rupturing force to the periphery of said first section when a tubular connector is inserted into said lumen and pressed inwardly against said first section without contact with said opposite section.

A pressure transmitting pod defining a chamber, said pod being for connection in flow-through relation to fluid flow tubing of a fluid flow set, said pod having a flexible, fluid impermeable diaphragm dividing the pod into separate compartments, a first of said compartments communicating with flow connectors for said fluid flow tubing, a second of said compartments communicating with a connection port for connection with a length of pressure tubing at one end thereof, which tubing is for sealed connection at its other end to a remote pressure connector of a pressure sensing machine, to transmit pressure from the second of said compartments through the pressure tubing to the pressure sensing machine for pressure monitoring, said diaphragm having a dome shape, and being sufficiently flexible to easily distort in a manner reflective of pressure changes, to vary the volumes of said one and other compartments.

A sealed port carried on a medical device, said port having a lumen which is sealed by a partition having a peripheral connection with the wall of said lumen;

• the partition having a diametrically opposed pair of peripheral, thin-wall tear lines adjacent to the lumen wall and comprising a major portion of the circumference of said partition, said partition also defining a thin-wall tear line extending substantially as a diameter across said partition from one of said peripheral tear lines to the other of said tear lines;
• said partition also defining a diametrically opposed pair of peripheral, thicker-wall, hinged portion circumferentially spacing the peripheral tear lines, whereby a connector entering said lumen wall can tear the tear lines to open the sealed port by causing a pair of torn-apart partition port portions to each pivot about said hinged portions.