Diaphragm pressure pod for medical fluids

• US 20070179422A1
• Filed: 11/09/2005
• Published: 08/02/2007
• Est. Priority Date: 11/09/2005
• Status: Active Grant

• Current Assignee: B Braun Medical Incorporated (B. Braun Holding GmbH & Co. KG)
• Original Assignee: Nxstage Medical Incorporated (Fresenius Medical Care AG)
• Inventors: Bell, David, Schnell, William, Utterberg, David, Wilson, Karen
• Granted Patent: US 8,092,414 B2
• Time in Patent Office: Days
• US Class Current: 604/4.10
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 1/3641 Pressure isolators
• CPC Class Codes: A61M 1/3655 Arterio-venous shunts or fistulae
• CPC Class Codes: A61M 39/00 Tubes, tube connectors, tube couplings, valves, access sites or the like, specially adapted for medical use for respiratory devices, e.g. tracheal tubes A61M16/00; artificial heart valves A61F2/24
• CPC Class Codes: F16L 29/005 joints with cut-off devices which can be perforated cut-off devices with a breakable closure member in general F16K13/04
• CPC Class Codes: Y10T 137/85978 With pump

Abstract

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

Claims

1. A tubular medical fluid flow set which comprises a pressure sensing pod defining a chamber, said pod being connected in flow-through relation to fluid flow tubing of said set, said pressure sensing pod defining a flexible, moveable, fluid-impermeable diaphragm dividing the pod into 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, and 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.

2. The set of claim 1 in which said sealed port is opened by engagement with a connector carried on a length of pressure tubing that also connects with a pressure measuring device.

3. The set of claim 2 in which said sealed port is sealed by a partition having a peripheral connection with a lumen wall of said sealed port, a major portion of said 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 the 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 sealed port, and pressed inwardly against said first section without contact with said opposite section.

4. The set of claim 3 in which said first section of the partition is at least twice as thick as the corresponding, opposite section.

5. The set of claim 1 in which said sealed port is sealed by a partition having a peripheral connection with a lumen wall of said sealed port, a major portion of said 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 the 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 sealed port, and pressed inwardly against said first section without contact with said opposite section.

6. The set of claim 5 in which said first section of the partition is at least twice as thick as the corresponding opposite section.

7. The set of claim 1 which is for handling extracorporeal blood flow.

8. The set of claim 7 in which the pod is directly and permanently attached to a connector for releasable, direct connection with an extracorporeal blood processing device.

16. The blood flow set of claim 1 in which said pod has a bottom wall which defines a transverse channel wall of U or V-shaped cross-section.

17. The blood flow set of claim 16 in which said channel wall is substantially aligned with, and has a size similar to, the inner diameter of the flow tubing of said set, for efficient fluid flow.

28. The set of claim 2 in which said sealed port is sealed by a partition having a peripheral connection with a lumen wall of said port, said partition having a diametrically opposed pair of peripheral, thin-walled tear lines adjacent to the lumen wall and comprising a major portion of the circumference of said partition, said partition also defining a thin-walled 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-walled hinged portions 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 portions to each pivot about said hinged portions.

29. The set of claim 28 in which a pressure tubing connector carried on the end of pressure tubing is sealingly positioned in said lumen wall, said lumen wall and pressure tubing connector defining mating, frustoconical sealing surfaces, said pressure tubing connector defining a partition-opening projection forwardly beyond its frustoconical sealing surface, said projection extending through said partition to open the sealed port.

9. 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.

10. The blood flow set of claim 9 in which said diaphragm occupies substantially said first position when the interior of said flow set is filled with negatively pressurized blood.

11. The blood flow set of claim 9 in which said flexible pressure tubing carries a connector for sequential connection with (1) a pressure sensing device and (2) a device to apply positive pressure through said outlet port to said chamber, to drive said diaphragm to the second position.

12. The blood flow set of claim 11 in which said pressure tubing is flexible and carries a flow clamp to retain said positive pressure at said diaphragm.

13. The blood flow set of claim 9 in which said pod has a bottom wall facing said chamber, which bottom wall defines a transverse channel having a wall of U or V-shaped cross-section, whereby the diaphragm in the second position does not block flow through the channel.

14. The blood flow set of claim 13 in which said channel wall is U-shaped and substantially contiguous with a wall portion of said flow tubing of said set.

15. The blood flow set of claim 9 in which said chamber connects to flow tubing which is pump segment tubing.

18. The blood flow set of claim 9 in which an access port is provided to communicate with the chamber interior at a side of said diaphragm opposed to said pressure tubing.

19. 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.

20. The method of claim 19 in which said chamber is previously used to sense subatmospheric blood pressure in said blood flow tube through a length of pressure tubing connected to said chamber, with the diaphragm being initially positioned to essentially maximize the blood holding volume in said chamber.

21. 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.

22. The pressure sensing pod of claim 21 which is directly and permanently attached to a connector for direct, releasable connection with an extracorporeal blood processing device.

23. The pressure sensing pod of claim 21 in which said sealed port is sealed by a partition having a peripheral connection with a lumen wall of said sealed port, a major portion of said 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 the corresponding, opposite section of said partition adjacent to the periphery of said portion, to focus rupturing force to the periphery of said first section when a tubular connector is inserted into said sealed port and pressed inwardly against said first section without contact with said opposite section.

24. The pressure sensing pod of claim 23 in which said first section of the partition is at least twice as thick as the corresponding, opposite section.

25. The pressure sensing pod of claim 21 in which said sealed port is sealed by a partition having a peripheral connection with a lumen wall of said port, said partition having a diametrically opposed pair of peripheral, thin-walled tear lines adjacent to the lumen wall and comprising a major portion of the circumference of said partition, said partition also defining a thin-walled 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-walled hinge portions 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 portions to each pivot about said hinged portions.

26. The pressure sensing pod of claim 25 in which a pressure tubing connector carried on the end of pressure tubing is sealingly positioned in said lumen wall, said lumen wall and pressure tubing connector defining mating, frustoconical sealing surfaces, said pressure tubing connector defining a partition-opening projection forwardly beyond its frustoconical sealing surface, said projection extending through said partition to open the sealed port.

27. The pressure sensing pod of claim 26 in which said partition is positioned in said lumen wall at a position in which it cannot be opened by a conventional, ISO standard male luer.

30. The set of claim 26 in which pressure sensing chamber of claim 26 in which said partition is positioned in said lumen wall at a position in which it cannot be opened by a conventional, ISO standard male luer.

31. 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.

32. The tubular connector of claim 31 in which said first section of the partition is at least twice as thick as the corresponding, opposite section.

33. 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.

34. The pressure pod of claim 33 in which said diaphragm of dome shape can vary the volume of said compartments at a pressure variation of 500 mm Hg by at least 2.5 cc.

35. The pressure pod of claim 33 in which said pressure tubing is permanently connected to said connection port of the pod, said pressure tubing having at its other end a remote tubing connector for connection to said machine remote pressure port during medical treatments.

36. The pressure pod of claim 33 in which said pressure tubing is capable of disconnection from the connection port of the pod.

37. The pressure pod of claim 36 in which said pod connection port is sealed from the atmosphere by an internal partition, said seal being operable by sealing attachment with a connector of said pressure tubing.

38. The pressure pod of claim 36 in which said partition is irreversibly opened by a connection of said pod connection port to a connector of said pressure tubing.

39. The pressure pod of claim 33 in which said pod defines a chamber which has a length at least twice its width.

40. The pressure pod of claim 39 in which said diaphragm has a width which is at least twice the depth of the dome of said diaphragm.

41. The pressure pod of claim 33 in which said diaphragm has a width which is at least twice the depth of the dome of said diaphragm.

42. 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.

43. The sealed port of claim 42 in which said partition is positioned in said lumen wall at a position in which it cannot be opened by a conventional, ISO standard male luer.