Gas separation devices

• US 7,517,387 B2
• Filed: 05/26/2003
• Issued: 04/14/2009
• Est. Priority Date: 06/24/2002
• Status: Active Grant

• Current Assignee: Gambro Lundia AB (Baxter International Inc.)
• Original Assignee: Gambro Lundia AB (Baxter International Inc.)
• Inventors: Semenzato, Nicolas, Chevallet, Jacques, Ribolzi, Francesco, Frugier, Alain
• Primary Examiner(s): Smith; Duane S
• Assistant Examiner(s): Theisen; Douglas J
• Application Number:
  US10/518,787
• Publication Number:
  US 20050247203A1
• Time in Patent Office: 2,150 Days
• Field of Search: 952/61, 95/19, 95/24, 962/09, 961/66, 962/11, 962/12, 961/74, 604/5.04, 604/122, 210/512.1
• US Class Current: 95/24
• CPC Class Codes: A61M 1/3437 downstream of the filter, e.g. post-dilution with filtrate
• 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 1/3676 by interposing a liquid layer between blood and air
• CPC Class Codes: A61M 2205/3382 Upper level detectors
• CPC Class Codes: A61M 2206/16 Rotating swirling helical flow, e.g. by tangential inflows
• CPC Class Codes: B01D 19/0057 the centrifugal movement being caused by a vortex, e.g. using a cyclone, or by a tangential inlet
• CPC Class Codes: B01F 25/10 Mixing by creating a vortex flow, e.g. by tangential introduction of flow components
• CPC Class Codes: B04C 5/103 Bodies or members, e.g. bulkheads, guides, in the vortex chamber cores B04C5/107

Abstract

A description is given of a gas separation device for a physiological fluid, comprising a containing body (6) having at least a first inlet aperture (7) for a physiological fluid, positioned with a tangential direction of access, at least one outlet aperture (9) for the said fluid, spaced apart from the said inlet aperture, and a guide element (17) housed within the said body. The guide element (17) has a continuous active surface (15) designed to contact and guide the said fluid and delimits, together with the containing body (6), a first annular chamber (20) into which the first inlet aperture (7) opens directly.

Claims

1. A gas separation device for a physiological fluid, comprising:

a containing body having an internal active surface, at least one first inlet aperture for a physiological fluid positioned with a tangential direction of access, and at least one outlet aperture for said fluid spaced apart from said first inlet aperture;

said containing body having;

a guide element housed at least partially within said containing body, said guide element having a continuous active surface configured to contact and guide said fluid, said guide element further comprising;

a first terminal portion configured to face towards said outlet aperture;

a second terminal portion axially opposed to the first terminal portion, said second terminal portion configured to face towards a second chamber extending above said guide element; and

a central portion having a cross section with a radial dimension that is reduced progressively away from said first and second terminal portions, to form an intermediate area having a minimum radial dimension; and

a first annular chamber formed between the active surface of said guide element and the internal active surface of said containing body.

2. A device according to claim 1, wherein said inlet aperture opens directly into said first chamber.

3. A device according to claim 1, wherein said guide element is wholly housed within the containing body, extends coaxially with the containing body, and is spaced axially apart from said outlet aperture.

4. A device according to claim 3, wherein the internal active surface of said containing body and the active surface of said guide element face each other and are shaped in the form of surfaces of revolution about a common axis of symmetry, said common axis of symmetry being transverse with respect to the tangential direction of access of said flow.

5. A device according to claim 1, wherein said outlet aperture is positioned in a lower end of said containing body, said guide element and said first chamber extending above said outlet aperture.

6. A device according to claim 1, wherein said guide element is a solid or internally hollow solid of rotation, configured to reduce the volume of at least said first chamber.

8. A device according to claim 1, wherein the second terminal portion has a cross section whose radial dimension is reduced progressively away from said outlet aperture.

9. A device according to claim 8, wherein the second terminal portion has a conical shape, said second terminal portion having a vertex opposed to the outlet aperture.

10. A device according to claim 1, wherein the central portion has a curved profile in longitudinal section.

7. A gas separation device for a physiological fluid, comprising:

a containing body having an internal active surface, at least one first inlet aperture for a physiological fluid positioned with a tangential direction of access, and at least one outlet aperture for said fluid spaced apart from said first inlet aperture;

said containing body having;

a guide element housed at least partially within said containing body, said guide element having a continuous active surface configured to contact and guide said fluid;

said guide element further comprising;

a central portion;

a first terminal portion configured to face towards said outlet aperture, said first terminal portion having a cross section whose radial dimension is reduced progressively towards said outlet aperture, and wherein said first terminal portion has a conical shape, said first terminal portion having a vertex configured to face towards the outlet aperture; and

a second terminal portion axially opposed to the first terminal portion, said second terminal portion configured to face towards a second chamber extending above said guide element; and

a first annular chamber formed between the active surface of said guide element and the internal active surface of said containing body.

11. A gas separation device for a physiological fluid, comprising:

a containing body having an internal active surface, at least one first inlet aperture for a physiological fluid positioned with a tangential direction of access, and at least one outlet aperture for said fluid spaced apart from said first inlet aperture, wherein said internal active surface of the containing body has;

a first area, of maximum radial dimension, extending around the central portion of the guide element;

a second area, whose radial dimension is reduced progressively towards the outlet aperture, the second area extending consecutively to the first area and substantially around the first terminal portion of the guide element; and

a third area, whose radial dimension is reduced progressively away from the outlet aperture, the third area extending consecutively to the first area and essentially around the second terminal portion of the guide element;

wherein said containing body comprises;

a guide element housed at least partially within said containing body, said guide element having a continuous active surface configured to contact and guide said fluid;

said guide element further comprising;

a central portion;

a first terminal portion configured to face towards said outlet aperture;

a second terminal portion axially opposed to the first terminal portion, said second terminal portion configured to face towards a second chamber extending above said guide element; and

a first annular chamber formed between the active surface of said guide element and the internal active surface of said containing body, wherein the first inlet aperture opens into said first annular chamber in said first area of the internal active surface of the containing body.

12. A device according to claim 11, wherein the first area of the active surface has a constant radius.

13. A gas separation device for a physiological fluid, comprising:

a containing body having an internal active surface, at least one first inlet aperture for a first physiological fluid positioned with a tangential direction of access, and at least one outlet aperture for said first physiological fluid spaced apart from said first inlet aperture;

said containing body having;

a guide element housed at least partially within said containing body, said guide element having a continuous active surface configured to contact and guide said first physiological fluid;

a first annular chamber formed between the active surface of said guide element and the internal active surface of said containing body; and

a second inlet aperture located above said first inlet aperture, said second inlet aperture being configured to convey a second physiological fluid into the containing body.

14. A device according to claim 13, further comprising a second chamber extending above said guide element in an axially consecutive position, said second chamber being in fluid communication with said first chamber and said second inlet aperture.

15. A device according to claim 14, wherein said second inlet aperture opens directly into said second chamber in a direction parallel to, and staggered with respect to, that of said first inlet aperture.

16. A device according to claim 14, wherein said containing body includes a third chamber being axially consecutive to said second chamber, said third chamber being configured to contain the gas separated from the first and second physiological fluids, and to extend in the top of said containing body.

17. A device according to claim 16, further comprising at least one service line having a first end in fluid communication with said third chamber by means of a fourth aperture formed in said containing body.

18. A device according to claim 17, further comprising at least one pressure sensor element associated for operation with said service line.

19. A device according to claim 17, further comprising at least one hydrophobic membrane associated for operation with an intermediate area of the service line.

20. A device according to claim 17, wherein the third chamber has a nominal volume V_c delimited below by a theoretical maximum level line BL and above by said fourth aperture.

21. A device according to claim 17, further comprising a pneumatic circuit operating in said service line for selectively sending gas to the service line and drawing gas from the service line.

22. A device according to claim 21, further comprising a liquid level sensor LLS located above a level BL, and a control unit connected to the sensor LLS and configured to control said pneumatic circuit to maintain the liquid level in the vicinity of said level BL.

23. A device according to claim 22, wherein the level sensor LLS operates in a section of the service line and said control unit is configured to cause the execution of the following steps:

determining whether LLS is signalling the presence of liquid, and, if so, executing the following sub-steps in sequence;

a) activation of the pneumatic circuit to drive towards the third chamber a volume V₁ equal to the volume between the section in which LLS operates and the fourth aperture,

b) activation of the pneumatic circuit to draw gas from the third chamber while LLS continues to signal the presence of liquid, and

c) activation of the pneumatic circuit to drive towards the third chamber a volume of liquid V₂, equal to V₁+V_c, where V_c is the volume of the third chamber;

if, on the other hand, LLS is not signalling the presence of liquid, executing the aforementioned three steps a), b) and c) at specified time intervals.

24. A device according to claim 17, further comprising at least one access site located in said service line for manually drawing fluid from said line or sending fluid into said line.

25. A device according to claim 22, wherein the level sensor LLS can operate on said containing body.

26. A gas separation device for a physiological fluid, comprising:

a containing body having an internal active surface, at least one first inlet aperture for a physiological fluid positioned with a tangential direction of access, and at least one outlet aperture for said fluid spaced apart from said first inlet aperture;

said containing body having;

a guide element housed at least partially within said containing body, said guide element having a continuous active surface configured to contact and guide said fluid; and

a first annular chamber formed between the active surface of said guide element and the internal active surface of said containing body;

said gas separation device further comprising;

a first line for sending the physiological fluid into said containing body through the first inlet aperture,

a second line for sending a second fluid into said containing body through a second inlet aperture,

a first pump operating to create a flow along the first line,

a second pump operating to create a flow along the second line, and

a control unit programmed to control the first and second pumps operating in the first and second lines and to ensure the constant presence in the containing body of a layer of said second fluid having a thickness that lies within a specified range, said layer being located above the physiological fluid.

27. A fluid mixing device with gas separation, comprising a containing body having an internal active surface and having at least one first inlet aperture for a first physiological fluid, and at least one fluid outlet aperture, spaced apart from said first inlet aperture, wherein the containing body has at least one second inlet aperture located above said first inlet aperture, said second inlet aperture being configured to convey a second fluid into the containing body to form a layer of said second fluid above said physiological fluid.

28. A device according to claim 27, wherein said containing body includes:

at least a first chamber extending in a lower area of the containing body and in fluid communication with said outlet aperture;

at least a second chamber, extending in an axially consecutive upper area and in fluid communication with said first chamber.

29. A device according to claim 28, wherein said containing body includes a third chamber being axially consecutive to said second chamber, said third chamber being configured to contain the gas separated from the first physiological fluid and the second fluid, and extending in the top of said containing body and having a fourth aperture.

30. A device according to claim 29, further comprising at least one service line having a first end in fluid communication with said third chamber by means of the fourth aperture formed in said containing body.

31. A device according to claim 30, further comprising at least one pressure sensor element associated for operation with said service line.

32. A device according to claim 31, further comprising at least one hydrophobic membrane associated for operation with an intermediate area of the service line, between the fourth aperture and the pressure sensor element.

33. A device according to claim 29, wherein the third chamber has a nominal volume V delimited below by a theoretical maximum level line BL and above by said fourth aperture.

34. A device according to claim 30, further comprising a pneumatic circuit for selectively sending gas to the service line and drawing gas from the service line.

35. A device according to claim 34, further comprising a liquid level sensor LLS located above a level BL, and a control unit connected to the sensor LLS and configured to control said pneumatic circuit to maintain the liquid level in the vicinity of said level BL.

36. A device according to claim 35, wherein said level sensor is located in said service line and said control unit is configured to cause the execution of the following steps:

determining whether LLS is signalling the presence of liquid, and, if so, executing the following sub-steps in sequence;

a) activation of the pneumatic circuit to drive towards the third chamber a volume V₁, equal to the volume between the section in which LSS operates and the fourth aperture,

b) activation of the pneumatic circuit to draw gas from the third chamber while LSS continues to signal the presence of liquid,

c) activation of the pneumatic circuit to drive towards the third chamber a volume of liquid V₂, equal to V₁+V_c, where V_cis the volume of the third chamber;

if, on the other hand, LLS is not signalling the presence of liquid, executing the aforementioned three steps a), b) and c) at specified time intervals.

37. A device according to claim 30, further comprising at least one access site located in said service line for manually drawing fluid from the service line or sending fluid to the service line.

38. A device according to claim 35, wherein the level sensor LLS operates on the said containing body.

39. A device according to claim 27, further comprising:

a first line for sending the physiological fluid into said containing body through the first inlet aperture,

a second line for sending the second fluid into said containing body through the second inlet aperture,

a first pump operating to create a flow along the first line,

a second pump operating to create a flow along the second line,

a programmable control unit for controlling the first and second pumps operating in the first and second lines and for ensuring the constant presence in the containing body of a layer whose thickness lies within a specified range, said layer being located above the first physiological fluid.

40. A device according to claim 39, wherein the control unit activates the second pump operating in the said second line in a continuous or intermittent mode to provide a specified flow rate at every specified time interval.

41. A device according to claim 39, further comprising a means for sensing the actual flow in the second line, said sensing means sending corresponding signals to said control unit.

42. A device according to claim 39, wherein the thickness of the said layer is smaller than the maximum diameter of the internal surface of the containing body.

43. A device according to claim 28, wherein said first inlet aperture opens directly into said first chamber in a tangential direction of access, and said second inlet aperture opens directly towards said second chamber in a direction of access parallel to that of said first aperture.

44. A device according to claim 43, further comprising a guide element housed at least partially within said body and having a continuous active surface designed to contact and guide said first physiological fluid, said first chamber having an annular configuration and being formed between the active surface of said element and the active surface of the containing body.

45. A device according to claim 44, wherein said guide element is wholly housed within the containing body, extends coaxially with the containing body, and is spaced axially apart from said outlet aperture.

46. A device according to claim 44, wherein the internal active surface of said containing body and the active surface of said guide element face each other and are shaped in the form of surfaces of revolution about a common axis of symmetry being transverse with respect to the tangential direction of access of said flow.

47. A device according to claim 44, wherein said outlet aperture is positioned in a lower end of said containing body, said guide element and said first chamber extending above said outlet aperture.

48. A device according to claim 46, wherein said guide element is a solid or internally hollow solid of rotation configured to reduce the volume of at least said first chamber.

49. A device according to claim 44, wherein said guide element comprises:

a central portion;

a first terminal portion, facing towards said outlet aperture; and

a second terminal portion, axially opposed to the first terminal portion and facing towards said second chamber.

50. A device according to claim 49, wherein the first terminal portion has a cross section whose radial dimension is reduced progressively towards said outlet aperture.

51. A device according to claim 50, wherein said first terminal portion has a conical shape, said first terminal portion having a vertex facing towards the outlet aperture.

52. A device according to claim 49, wherein the second terminal portion has a cross section whose radial dimension is reduced progressively away from said outlet aperture.

53. A device according to claim 52, wherein said second terminal portion has a conical shape, said second terminal portion having a vertex opposed to the outlet aperture.

54. A device according to claim 49, wherein the central portion has a cross section with a radial dimension that is reduced progressively away from said first and second terminal portions to form an intermediate area having a minimum radial dimension.

55. A device according to claim 54, wherein the central portion has a curved profile in longitudinal section.

56. A device according to claim 49, wherein said active surface of the containing body has:

a first area, of maximum radial dimension, extending around the central portion of the guide element;

a second area, whose radial dimension is reduced progressively towards the outlet aperture, the second area extending consecutively to the first area and essentially around the first terminal portion of the guide element; and

a third area, whose radial dimension is reduced progressively away from the outlet aperture, the third area extending consecutively to the first area and essentially around the second terminal portion of the guide element.

57. A device according to claim 56, wherein the first inlet aperture opens into the said first chamber, in said intermediate first area.

58. A device according to claim 56, wherein the first area of the active surface of the containing body has a constant radius.

59. A fluid mixing method with gas separation, comprising the following steps:

providing a containing body having an internal active surface and having at least a first inlet aperture, at least one fluid outlet aperture spaced apart from said first inlet aperture, and at least a second inlet aperture located above said first inlet aperture;

sending a first physiological fluid into the containing body through said first aperture;

conveying a second fluid into the containing body through said second aperture to form a layer of said second fluid above said first physiological fluid;

conveying a separated gas from said first physiological fluid and said second fluid above said layer.

60. A method according to claim 59, further comprising the steps of:

measuring the flow rate of said first physiological fluid;

measuring the flow rate of said second fluid;

regulating the flow rate of said first physiological fluid and said second fluid to provide a layer of said second fluid with a thickness lying within a specified range.

61. A method according to claim 60, wherein said second fluid is sent, in continuous or intermittent mode, in a direction of access to the containing body parallel to that of said first physiological fluid.

62. A method according to claim 60, wherein the thickness of said layer is kept below the maximum diameter of the internal surface of the containing body.