DIALYSIS VALVE AND METHOD

• US 20090209921A1
• Filed: 04/28/2009
• Published: 08/20/2009
• Est. Priority Date: 04/23/2003
• Status: Active Grant

• Current Assignee: Interrad Medical, Inc.
• Original Assignee: Interrad Medical, Inc.
• Inventors: Rosenberg, Michael S., Claude, Timothy J., Hunter, David W., Barlow, Edward A.
• Granted Patent: US 7,811,264 B2
• Time in Patent Office: Days
• US Class Current: 604/246
• CPC Class Codes: A61M 1/3655 Arterio-venous shunts or fistulae
• CPC Class Codes: A61M 2205/0266 Shape memory materials
• CPC Class Codes: A61M 39/22 Valves or arrangement of valves A61M39/02, A61M39/0247, A61M39/16 take precedence; regulating valves in infusion systems A61M5/16881; in devices worn by the patient for the reception of urine, faeces, catamenial or other discharge, or in colostomy devices A61F5/4405
• CPC Class Codes: A61M 39/228 with a tubular diaphragm constrictable by radial fluid force

Abstract

A dialysis valve includes a tube attached between an artery and a vein which, when elongated, simultaneously narrows in diameter at least one location. The narrowed portion of the tube decreases the volume and velocity between the arterial and venous side of the patient to prevent damage or intimal hyperplasia on the venous side between dialysis treatments. When the valve is opened for dialysis, an unrestricted blood flow exists between the arterial and venous side, permitting a controlled, open blood flow during dialysis.

Claims

1. A method of controlling blood flow between and during dialysis treatments, comprising:

implanting a dialysis valve comprising a tube between a patient'"'"'s vein and an artery, the tube operable to convey fluids and defining a longitudinal dimension, a diameter and an inner surface, wherein the tube comprises a braided nitinol structure processed to exhibit superelasticity below normal human body temperature coated with an elastomer allowing the tube to be repeatedly altered in longitudinal dimension and in diameter and still maintain fluid containing capability;

narrowing the diameter of the tube in an adjustable manner between dialysis treatments at at least one location along the longitudinal dimension, wherein the diameter of the tube is narrowed while not fully closing the diameter to thereby provide blood flow through the tube between dialysis treatments; and

opening the diameter of the tube at the narrowed location by adjustably changing the longitudinal dimension of the tube to conduct a dialysis treatment, wherein the diameter of the tube is opened to thereby provide increased blood flow through the tube during the dialysis treatment.

2. The method of claim 1, wherein the inner surface of the tube at the narrowed location is in a substantially circular configuration.

3. The method of claim 1, wherein the inner surface of the tube is substantially smooth and comprises an anti-thrombogenic coating.

4. The method of claim 1, wherein the diameter of the tube is narrowed to provide blood flow through the tube between dialysis treatments at a blood flow rate of less than about 300 cc per minute.

5. The method of claim 1, wherein the dialysis valve comprises an adjustable bellows device coupled to the tube operable to convey fluids.

6. The method of claim 1, wherein the dialysis valve comprises an adjustable balloon device in contact with the tube operable to convey fluids.

7. The method of claim 6, wherein the adjustable balloon device surrounds the tube.

8. The method of claim 1, wherein the dialysis valve comprises an adjustable shape-memory spring device attached to each end of the tube.

9. The method of claim 1, further comprising the adjustable shape-memory spring device being in electrical communication with a controller device.

10. A method of controlling blood flow between and during dialysis treatments, comprising:

implanting a dialysis valve device in a bodily limb between an artery and a vein;

attaching an arterial fistula graft of the dialysis valve device to the artery in the bodily limb;

attaching a venous fistula graft of the dialysis valve device to the vein in the bodily limb;

causing an adjustable tube of the dialysis valve device to convey blood from the arterial fistula graft to the venous fistula graft, the tube extending for a longitudinal length and defining an inner surface that is substantially smooth;

controlling an actuator of the dialysis valve device to selectively adjust from a first length to a second length in response to fluid or electric control, the actuator being coupled with the tube so that when the actuator adjusts from the first length to the second length, the tube contemporaneously increases in longitudinal length and decreases in diameter at a narrowed portion.

11. The method of claim 10, the step of controlling the actuator causes the tube to decrease in diameter at the narrowed portion while not fully closing the tube to blood flow so that the tube constricts and provides blood flow therethrough at an increased velocity to hinder the formation of thrombus or clotting.

12. The method of claim 11, wherein the tube decreases in diameter at a narrowest portion while not fully closing to provide a blood flow rate through the tube of less than about 300 cc per minute when the tube is implanted between an artery and a vein.

13. The method of claim 11, further comprising controlling the actuator of the dialysis valve device to selectively adjust from the second length to the first length so that the tube contemporaneously decreases in longitudinal length and increases in diameter at a narrowed portion.

14. The method of claim 10, wherein the adjustable tube of the dialysis valve device comprises a braided nitinol structure having a flexible coating such that the inner surface of the tube is substantially smooth and coated with an anti-thrombogenic material.

15. The method of claim 10, wherein the step of implanting the dialysis valve device in the bodily limb comprises implanting the dialysis valve device in an arm.

16. The method of claim 10, wherein the step of controlling the actuator of the dialysis valve device comprises adjusting a fluid controlled bellows from the first length to the second length, the bellows being in fluid communication with an actuation port that receives fluid through a self-sealing membrane for adjustment of the longitudinal length of the tube.

17. The method of claim 16, wherein when the fluid is urged into an inner space defined by the bellows, the bellows increases in length and thereby actuates the tube to contemporaneously increase in longitudinal length and decrease in diameter at the narrowed portion.

18. The method of claim 16, wherein the step of implanting the dialysis valve device in the bodily limb comprises arranging the self-sealing adjacent to skin of the bodily limb.

19. The method of claim 10, wherein the step of controlling the actuator of the dialysis valve device comprises adjusting an inflatable balloon to a selected degree of inflation, the balloon acting upon the tube so that, when the balloon is inflated, the tube contemporaneously increases in longitudinal length and decreases in diameter at the narrowed portion.

20. The method of claim 10, rein the step of controlling the actuator of the dialysis valve device comprises adjusting a shape-memory spring attached to the tube such that, when the spring is controlled to shift from the first length to the second length, the tube contemporaneously increases in longitudinal length and decreases in diameter at the narrowed portion.