SYSTEMS AND METHODS FOR MULTIFUNCTIONAL VOLUMETRIC FLUID CONTROL

• US 20140217027A1
• Filed: 02/01/2013
• Published: 08/07/2014
• Est. Priority Date: 02/01/2013
• Status: Active Grant

• Current Assignee: Mozarc Medical US LLC
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Meyer, Thomas E., Lura, David B., Pudil, Bryant J., Gerber, Martin T.
• Granted Patent: US 9,623,164 B2
• Time in Patent Office: Days
• US Class Current: 210/646
• CPC Class Codes: A61M 1/1524 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/154 with sensing means or components thereof
• CPC Class Codes: A61M 1/1562 Details of incorporated reservoirs
• CPC Class Codes: A61M 1/15632 the filter being a dialyser
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1601 Control or regulation
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1621 Constructional aspects thereof semi-permeable membranes for separation processes characterised by their properties B01D69/00; semi permeable membranes characterised by their material B01D71/00
• CPC Class Codes: A61M 1/165 with a dialyser bypass on the dialysis fluid line
• CPC Class Codes: A61M 1/1652 Holding or locking systems for the membrane unit
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/1658 Degasification
• CPC Class Codes: A61M 1/1664 with temperature control
• CPC Class Codes: A61M 1/1666 by dissolving solids
• CPC Class Codes: A61M 1/1668 Details of containers
• CPC Class Codes: A61M 1/1672 using membrane filters, e.g. for sterilising the dialysate
• CPC Class Codes: A61M 1/1676 containing proteins, e.g. albumin
• CPC Class Codes: A61M 1/169 using chemical substances
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/3413 Diafiltration
• CPC Class Codes: A61M 1/3437 : downstream of the filter, e.g. post-dilution with filtrate
• CPC Class Codes: A61M 1/3609 : Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 1/362262 : Details of incorporated reservoirs
• CPC Class Codes: A61M 1/362264 : the filter being a blood filter
• CPC Class Codes: A61M 1/362266 : Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/3626 : Gas bubble detectors
• CPC Class Codes: A61M 1/3627 : Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: A61M 1/3643 : Priming, rinsing before or after use
• CPC Class Codes: A61M 1/3644 : Mode of operation
• CPC Class Codes: A61M 1/3649 : using dialysate as priming or rinsing liquid
• CPC Class Codes: A61M 1/365 : through membranes, e.g. by inverted trans-membrane pressure [TMP]
• CPC Class Codes: A61M 2205/3317 : Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 : PH measuring means
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 : Temperature
• CPC Class Codes: A61M 2205/50 : with microprocessors or computers
• CPC Class Codes: A61M 2205/502 : User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2205/505 : Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches
• CPC Class Codes: A61M 2209/06 : Packaging for specific medical equipment
• CPC Class Codes: A61M 2230/65 : Impedance, e.g. conductivity, capacity

Abstract

Systems and methods for controlling fluid movement and volumes of fluid between a subject and a controlled compliant flow path. The controlled compliant flow path has a means for selectively metering in and metering out fluid from the controlled compliant flow path. An extracorporeal flow path is in fluid communication with the controlled compliant flow path across a semi-permeable membrane where the extracorporeal flow path has a first terminal end and a second terminal end.

Claims

1. A system for controlling fluid movement between a subject and a controlled compliant flow path, comprising:

a controlled compliant flow path having a means for selectively metering in and metering out fluid from the controlled compliant flow path;

an extracorporeal flow path in fluid communication with the controlled compliant flow path across a semi-permeable membrane wherein the extracorporeal flow path has a first terminal end and a second terminal end.

2. The system of claim 1, wherein the first terminal end and the second terminal end are connectable together to form a junction.

3. The system of claim 2, wherein the junction is between the terminal ends of an arterial line and a venous line of an extracorporeal circuit.

4. The system of claim 1, wherein the extracorporeal flow path has a blood pump for circulating blood through the extracorporeal flow path, and a first valve and/or a second valve to selectively permit flow through a first conduit and a second conduit in fluid communication across either a dialyzer or hemofilter on the extracorporeal flow path.

5. The system of claim 1, wherein the means for selectively metering in and metering out fluid from the controlled compliant flow path is a control pump in fluid communication with a control reservoir.

6. The system of claim 5, wherein at least the control pump coordinately operates with a first valve and/or a second valve to control fluid movement.

7. The system of claim 2, wherein at least the blood pump coordinately operates with the first and/or second valve to control fluid movement.

8. The system of claim 5, wherein the control pump and a blood pump on the extracorporeal flow path coordinately operate with the first valve and/or second valve to control fluid movement.

9. The system of claim 2, wherein the extracorporeal flow path has a hydrophobic vent or a priming overflow reservoir connected to the junction.

10. The system of claim 2, wherein at least one of the first valve or second valve is a pinch valve.

11. The system of claim 1, further comprising a sorbent cartridge on the controlled compliant flow path wherein a fluid passes through the sorbent cartridge prior to crossing the semi-permeable membrane.

12. The system of claim 1, further comprising a microbial filter on the controlled compliant flow path wherein fluid passes through the microbial filter prior to crossing the semi-permeable membrane.

13. The system of claim 1, further comprising a microbial filter on the controlled compliant flow path wherein fluid passes through the microbial filter prior to entering the extracorporeal flow path.

14. The system of claim 1, further comprising at least one bubble detector to detect air in the extracorporeal flow path at any one of a first conduit, a second conduit, or both.

15. The system of claim 1, wherein the controlled compliant flow path has a means for conductivity measurement to verify that a sodium content is within predetermined limits.

16. The system of claim 1, wherein the controlled compliant flow path has a means for adjusting the solute concentration of fluid in the controlled compliant flow path.

17. The system of claim 16, wherein the means for adjusting the solute concentration of fluid in the controlled compliant flow path is a sodium chloride source that can increase a sodium chloride concentration of fluid passing through the controlled compliant flow path and a buffer source that can increase a buffer concentration of fluid passing through the controlled compliant flow path.

18. The system of claim 16, wherein the means for adjusting the solute concentration of fluid in the controlled compliant flow path is a sodium chloride cartridge that can increase a sodium chloride concentration of fluid passing through the cartridge and a buffer source cartridge that can increase a buffer concentration of fluid passing through the buffer source cartridge.

31. A method of priming a dialyzer and extracorporeal flow path using the system of claim 9, comprising the steps of:

operating a control pump to transfer a first volume of fluid from the control reservoir to a controlled compliant flow path;

opening a second valve on the extracorporeal flow path while operating the control pump to transfer a second volume of fluid from the control reservoir to the controlled compliant flow path;

closing the second valve;

opening an first valve on the extracorporeal flow path while coordinately operating the control pump and blood pump to transfer a third volume of fluid from the control reservoir to the controlled compliant flow path and to the extracorporeal circuit;

closing the first valve and stopping the control pump and the blood pump.

32. The method of claim 31, further comprising operation of a circulating pump in fluid communication with a controlled compliant flow path.

33. The method of claim 31, wherein the first volume of fluid is approximately equal to the priming volume of a dialyzer or a hemofilter;

wherein opening the second valve causes an equal volume of fluid to move to the extracorporeal flow path, the second volume being approximately equal to the priming volume of the second conduit of the extracorporeal flow path; and

the third volume being approximately equal to the priming volume of the first conduit.

34. The method of claim 31, further comprising the step of operating a circulating pump to move air from the dialyzer to a degassing module in fluid communication with the controlled compliant flow path.

35. The method of claim 31, further comprising the steps of:

opening the first and second valves and operating the blood pump to circulate the priming fluid through the extracorporeal circuit;

closing the first valve and stopping the blood pump;

operating the control pump to transfer a fourth volume of priming fluid to the controlled compliant flow path to cause an equal volume of fluid to move through the second conduit to a priming overflow reservoir in fluid communication with the junction;

closing the second conduit and operating the control pump to transfer a fifth volume of fluid from the control reservoir to the controlled compliant flow path while operating the blood pump in coordination with the control pump to cause an equal volume of fluid to move through a first conduit to a priming overflow reservoir in fluid communication with the junction.

36. A method of initiating a therapy session using the system of claim 1, comprising the steps of:

connecting the first terminal end to a first blood access connection of a subject;

opening a first valve on the extracorporeal flow path while operating a blood pump;

stopping the blood pump and closing the second valve and disconnecting the second terminal end from the overflow reservoir, and

connecting the second terminal end to a second blood access connection of a subject.

37. The method of claim 36, wherein opening the first valve moves a predetermined volume of blood into the extracorporeal flow path and displaces an approximately equal volume of priming fluid to an overflow reservoir in fluid communication with the second terminal end.

38. A method of returning a priming fluid and initiating a therapy session using the system of claim 1, comprising the steps of:

connecting the second terminal end to a first blood access connection of the subject;

opening a second valve on the extracorporeal flow path while operating a control pump to move a predetermined first volume of blood into the extracorporeal flow path;

stopping the control pump and closing the second valve and connecting the first terminal end to a second blood access connection of the subject;

opening an first valve and operating a blood pump and the control pump together at approximately equal volumetric flow rates to move a second volume of blood into the extracorporeal flow path.

39. The method of claim 38, further comprising

displacing an approximately equal volume of priming fluid from a first segment of the extracorporeal flow path across the semipermeable membrane to a control reservoir on the controlled compliant flow path;

and

displacing an approximately equal volume of priming fluid from a second segment of the extracorporeal flow path across the semipermeable membrane to the control reservoir wherein the first and second predetermined volumes are approximately equal to the total priming volume of the extracorporeal flow path.

40. A method of returning a priming fluid and initiating a therapy session using the system of claim 1, comprising the steps of:

connecting the first terminal end to a first blood access connection of the subject;

opening a first valve on the extracorporeal flow path while operating a control pump to move a predetermined first volume of blood into the extracorporeal flow path;

stopping the control pump and closing the first valve and connecting the second terminal end to a second blood access connection of the subject;

opening an second valve and operating a blood pump and the control pump together at approximately equal volumetric flow rates to move a second volume of blood into the extracorporeal flow path.

41. The method of claim 40, further comprising

displacing an approximately equal volume of priming fluid from a first segment of the extracorporeal flow path across the semipermeable membrane to a control reservoir on the controlled compliant flow path;

and

displacing an approximately equal volume of priming fluid from a second segment of the extracorporeal flow path across the semipermeable membrane to the control reservoir, wherein the first and second predetermined volumes are approximately equal to the total priming volume of the extracorporeal flow path.

42. The method in any one of claims 31-9, wherein either the blood or control pump is a bidirectional pump.

43. A method for delivering a fluid bolus to a subject using the system of claim 1 or 11, comprising the steps of:

transferring a predetermined volume of the physiological-compatible fluid from the control reservoir to the controlled compliant flow path to cause the physiological-compatible fluid to transverse a dialyzer membrane or a microbial filter from the controlled compliant flow path to the extracorporeal flow path; and

conveying the physiologically compatible fluid through the extracorporeal conduit flow path to the subject.

44. The method of claim 43, wherein the predetermined volume of the physiological-compatible fluid from the control reservoir is equal to the volume of the physiological-compatible fluid and wherein the volume of the physiologically compatible fluid is equal to the volume in the extracorporeal conduit flow path.

45. The method of claim 43, further comprising measuring the conductivity of the fluid before it passes to the extracorporeal flow path.

46. The method of claim 43, further comprising operating an infusate pump to adjust a concentration of a solute in the fluid before the fluid passes to the extracorporeal flow path.

47. A method for returning blood from an extracorporeal flow path to a subject using the system of claim 1 or 11, comprising the steps of:

transferring a volume of fluid from the control reservoir to the controlled compliant flow path to cause a volume of the fluid to transverse a dialyzer membrane or a microbial filter from the controlled compliant flow path to the extracorporeal flow path; and

conveying the volume of the physiologically compatible fluid through the extracorporeal flow path to displace the blood from the extracorporeal flow path to the subject.

48. The method of claim 47, wherein the volume of fluid from the control reservoir to the controlled compliant flow path causes an equal volume of the fluid to transverse a dialyzer membrane or a microbial filter from the controlled compliant flow path to the extracorporeal flow path and wherein the volume of the physiologically compatible fluid is equal to the volume conveyed through the extracorporeal flow path to the subject.

49. The method of claim 47, where the equal volume is approximately equal to a priming volume of the extracorporeal flow path.

50. The method of claim 47, further comprising the steps of:

conveying a first volume of the fluid through a first segment of the extracorporeal flow path;

conveying a second volume of the fluid through a second segment of the extracorporeal flow path;

wherein transferring the first volume of the fluid from the control reservoir to the controlled compliant flow path causes a first equal volume of the fluid to transverse the semipermeable membrane from the controlled compliant flow path to the extracorporeal flow path, and transferring the second volume of the fluid from the control reservoir to the controlled compliant flow path causes a second equal volume of the fluid to transverse the semipermeable membrane from the controlled compliant flow path to the extracorporeal flow path.

51. The method of claim 50 wherein the first volume of the fluid approximately equals a first priming volume of the first segment of the extracorporeal flow path and the second volume of the fluid approximately equals a second priming volume of the second segment of the extracorporeal flow path.

52. The method of claim 47, wherein a blood pump and a control pump are operated coordinately to convey fluid through a conduit of the extracorporeal flow path.

53. The method of claim 47, wherein the control pump is a bidirectional pump.

54. The method of claim 47, wherein the extracorporeal flow path has a blood pump for circulating blood through the extracorporeal flow path, and

a first valve and/or a second valve to selectively permit flow through the tubing forming the extracorporeal flow path.

55. The method of claim 47, wherein the means for selectively metering in and metering out fluid from the controlled compliant flow path is a control pump in fluid communication with a control reservoir.

56. The method of claim 47, wherein at least the control pump coordinately operates with a first valve and/or a second valve to control fluid movement.

57. The method of claim 47, wherein at least the blood pump coordinately operates with the first valve and/or second valve to control fluid movement.

58. The method of claim 47, wherein the control pump and a blood pump on the extracorporeal flow path coordinately operate with the first valve and/or second valve to control fluid movement.

59. The method of claim 47, wherein at least one of the first valve or second valve is a pinch valve.

60. The method of claim 47, further comprising the step of passing a fluid through a sorbent cartridge on the controlled compliant flow path wherein the fluid passes through the sorbent cartridge prior to crossing the semi-permeable membrane into the extracorporeal flow path.

61. The method of claim 47, further comprising the step of passing a fluid though a microbial filter on the controlled compliant flow path wherein the fluid passes through the microbial filter prior to crossing the semi-permeable membrane into the extracorporeal flow path.

62. The method of claim 47, wherein the controlled compliant flow path has a means for conductivity measurement to verify that a sodium content is within predetermined limits.

63. The method of claim 47, wherein the controlled compliant flow path has a means for adjusting the conductivity of fluid in the controlled compliant flow path.

19. A reservoir for use in a system for performing any one of hemodialysis, hemodiafiltration, hemofiltration, comprising:

a control pump in fluid communication with a controlled compliant flow path; and

a common reservoir in fluid communication with a control pump wherein the common reservoir contains any one of a dialysate, a filtrate, a volume of a physiologically compatible priming solution, a volume of a physiologically compatible solution to provide a bolus of fluid to a subject receiving treatment, a volume of physiologically compatible solution to provide solution for return of blood from an extracorporeal flow path to a subject receiving treatment, a volume of solution returned to the common reservoir from an extracorporeal flow path when blood from a subject is introduced to the extracorporeal flow path, and combinations thereof.

20. The reservoir of claim 19, wherein the dialysate is produced by the system for performing hemodialysis or hemodiafiltration from water introduced to a conduit of a controlled compliant flow path, a sorbent cartridge, a source of sodium introduced to a conduit of the controlled compliant flow path, and optionally solutes other than sodium introduced to a conduit of the controlled compliant flow path.

21. The reservoir of claim 19, wherein the volume of a physiologically compatible priming fluid is produced by the system from water introduced to a conduit of a controlled compliant flow path, a sorbent cartridge, a source of sodium introduced to a conduit of the controlled compliant flow path, and optionally solutes other than sodium introduced to a conduit of the controlled compliant flow path.

22. The reservoir of claim 19, wherein the volume of a physiologically compatible solution to provide a bolus of fluid to a subject receiving treatment is produced by the system from water introduced to a conduit of the controlled compliant flow path, a sorbent cartridge and a source of sodium introduced to a conduit of the controlled compliant flow path, and optionally solutes other than sodium introduced to a conduit of the controlled compliant flow path.

23. The reservoir of claim 19, wherein the volume of a physiologically compatible solution to provide fluid volume for return of blood from the extracorporeal flow path to a subject receiving treatment is produced by the system from water introduced to a conduit of the controlled compliant flow path, a sorbent cartridge, and a source of sodium introduced to a conduit of the controlled compliant flow path, and optionally solutes other than sodium introduced to a conduit of the controlled compliant flow path.

24. The reservoir of claims 20, 21 and 23, wherein a portion of the fluid volume contained in the reservoir originates from a spent dialysate, a filtrate from the blood of a subject, or a priming fluid that has been returned to the controlled compliant flow path from the extracorporeal flow path.

25. The reservoir of claim 19, wherein the physiologically compatible priming fluid delivered from the common reservoir to a conduit of the controlled compliant flow path is in fluid communication with an extracorporeal flow path for priming of the extracorporeal flow path wherein the priming fluid is passed through a sorbent cartridge and at least a microbial filter or a dialyzer membrane.

26. The reservoir of claim 19, wherein a volume of fluid is returned to the common reservoir from an extracorporeal flow path when blood from a subject is introduced to the extracorporeal flow path.

27. The reservoir of claim 19, wherein the volume of physiologically compatible solution to provide solution for return of blood from an extracorporeal flow path to a subject receiving treatment is passed through a sorbent cartridge and is optionally infused by a source of cations introduced to a conduit of the controlled compliant flow path to produce the dialysate or a replacement fluid.

28. The reservoir of claim 19, wherein the volume of a physiologically compatible solution to provide a bolus of fluid to a subject receiving treatment is first passed through a sorbent cartridge and at least a microbial filter or dialyzer membrane prior to being returned to the extracorporeal flow path.

29. The reservoir of claim 19, wherein the volume of a physiologically compatible priming solution, the volume of a physiologically compatible solution to provide a bolus of fluid to a subject receiving treatment, the volume of physiologically compatible solution to provide solution for return of blood from an extracorporeal flow path to a subject receiving treatment, the volume of solution returned to the common reservoir from an extracorporeal flow path when blood from a subject is introduced to the extracorporeal flow path, and combinations thereof are drained from the common reservoir following conclusion of a treatment.

30. The reservoir of claim 29, wherein the volume of fluid in the reservoir further comprises fluids that are drained from the extracorporeal flow path, the controlled compliant flow path, or an infusate reservoir following conclusion of a treatment.