Bubble trap chamber

• US 6,019,824 A
• Filed: 06/09/1998
• Issued: 02/01/2000
• Est. Priority Date: 06/09/1998
• Status: Expired due to Term

• Current Assignee: Nxstage Medical Incorporated (Fresenius Medical Care AG)
• Original Assignee: Medisystems Technology Corporation
• Inventors: Schnell, William J.
• Primary Examiner(s): SMITH, DUANE
• Application Number:
  US09/094,417
• Time in Patent Office: 602 Days
• Field of Search: 95/261, 96/177, 96/195, 96/208, 96/209, 96/216, 210/188, 604/4, 604/5, 604/126, 604/405, 604/406
• US Class Current: 96/177
• CPC Class Codes: A61M 1/3627 Degassing devices; Buffer reservoirs; Drip chambers; Blood filters
• CPC Class Codes: B01D 19/0031 by filtration

Abstract

A tubular set for the conveyance of blood includes flexible set tubing and a bubble trap chamber connected to the tubing for any desired extracorporeal blood transport process. The bubble trap chamber includes a housing defining an outer wall, a flow inlet to the interior of the housing, and a flow outlet at or near the bottom of the housing. The housing also includes an inner wall adjacent to its top. The inner wall is radially inwardly spaced from the outer wall within the chamber, extending circumferentially and generally parallel to the outer wall for at least about 90° of the circumference of the outer wall and preferably at least 180°, to define a circumferential passageway between the inner and outer walls. The flow inlet communicates with the circumferential passageway, so that blood can be directed to flow from the inlet horizontally and circumferentially through the passageway to a pair of passageway outlets. The passageway outlets are spaced in the chamber from the inlet, with the effect that the horizontal blood flow path of blood in the chamber is lengthened with less flow velocity, which improves the bubble removal capability of the bubble trap chamber.

Claims

1. A tubular set for the conveyance of blood, which set comprises flexible set tubing and a bubble trap chamber connected to said tubing, said bubble trap chamber comprising a housing defining an outer wall, a flow inlet to the interior of said housing, and a flow outlet at or near the bottom of said housing, said housing comprising an inner wall adjacent to the top of said housing, said inner wall being radially inwardly spaced from said outer wall within said chamber and extending circumferentially and generally parallel to said outer wall for at least about 90°

of the circumference of the outer wall, to define a circumferential passageway between the inner and outer walls, said flow inlet communicating with said circumferential passageway, whereby blood is directed to flow from said flow inlet horizontally and circumferentially through the passageway to at least one passageway outlet, which outlet is spaced in the chamber from said flow inlet, to lengthen the horizontal flow path of blood in said chamber.

2. The set of claim 1 in which said housing is of circular cross section near its bottom and proportioned to fit into conventional hemodialysis bubble detectors.

3. The set of claim 1 in which said housing defines a bottom wall for said circumferential passageway.

4. The set of claim 1 in which said inner wall and circumferential passageway extend for at least about 180°

of the circumference of said outer wall.

5. The set of claim 1 in which said flow inlet defines an aperture positioned to direct blood with horizontal flow into said circumferential passageway.

6. The set of claim 1 in which said flow inlet is centrally spaced relative to said inner wall, for bidirectional flow from said flow inlet through said circumferential passageway, each end of the circumferential passageway defining a separate passageway outlet.

7. A tubular set for the conveyance of blood, which set comprises flexible set tubing and a bubble trap chamber connected to said tubing, said bubble trap chamber comprising a housing defining an outer wall, a flow inlet to the interior of said housing, and a flow inlet at or near the bottom of said housing, said housing being of circular cross section near its bottom and proportioned to fit into conventional hemodialysis bubble detectors, said housing comprising an inner wall adjacent to the top of said housing, said inner wall being radially inwardly spaced from said outer wall within said chamber and extending circumferentially and generally parallel to said outer wall for at least about 90°

of the circumference of the outer wall, to define a circumferential passageway between the inner and outer walls, said flow inlet communicating with said circumferential passageway, and said housing also defining a bottom wall for said circumferential passageway, whereby blood is directed to flow from said inlet horizontally and circumferentially through the passageway to at least one passageway outlet, which is spaced in the chamber from said flow inlet, to lengthen the horizontal flow path of blood in said chamber.

8. The set of claim 7 in which said inner wall and circumferential passageway extend for at least about 180°

of the circumference of said outer wall.

9. The set of claim 8 in which said flow inlet is centrally spaced relative to said inner wall, for bidirectional flow from said flow inlet through said circumferential passageway, each end of the circumferential passageway defining a separate passageway outlet.

10. The set of claim 9 in which said flow inlet defines an aperture positioned to direct blood with horizontal flow into said circumferential passageway.

11. A bubble trap chamber for use in the extracorporeal flow of blood, said bubble trap chamber comprising a housing defining an outer wall, a flow inlet to the interior of said housing, and a flow inlet at or near the bottom of said housing, said housing comprising an inner wall adjacent to the top of said housing, said inner wall being radially inwardly spaced from said outer wall within said chamber and extending circumferentially and generally parallel to said outer wall for at least about 90°

of the circumference of the outer wall, to define a circumferential passageway between the inner and outer walls, said flow inlet communicating with said circumferential passageway, whereby blood is directed to flow from said inlet horizontally and circumferentially through the passageway to at least one passageway outlet, which outlet is spaced in the chamber from said inlet, to lengthen the horizontal flow path of blood in said chamber.

12. The bubble trap chamber of claim 11 in which said housing is of circular cross section near its bottom and proportioned to fit into conventional hemodialysis bubble detectors.

13. The bubble trap chamber of claim 11 in which said housing defines a bottom wall for said circumferential passageway.

14. The bubble trap chamber of claim 11 in which said inner wall and circumferential passageway extend for at least about 180°

of the circumference of said outer wall.

15. The bubble trap chamber of claim 11 in which said flow inlet defines an aperture positioned to direct blood with horizontal flow into said circumferential passageway.

16. The bubble trap chamber of claim 11 in which said flow inlet is centrally spaced relative to said inner wall, for bidirectional flow from said flow inlet through said circumferential passageway, each end of the circumferential passageway defining a separate passageway outlet.

17. The bubble trap chamber of claim 11 in which said housing defines a bottom wall for said circumferential passageway, said inner wall and circumferential passageway extending for at least about 180°

of the circumference of said outer wall.

18. The bubble trap chamber of claim 17 in which said flow inlet is centrally spaced relative to said inner wall, for bidirectional flow from said flow inlet through said circumferential passageway, each end of the circumferential passageway defining a separate passageway outlet.

19. The bubble trap chamber of claim 18 in which said housing is of circular cross section near its bottom and proportioned to fit into conventional hemodialysis bubble detectors.

20. The bubble trap chamber of claim 18 in which said flow inlet defines an aperture positioned to direct blood with horizontal flow into said circumferential passageway.