Hemodiafiltration device

Claim 2

A hemodiafiltration cartridge comprising: means defining a dialysate chamber; means defining a dialysate inlet; means defining a dialysate outlet; means defining a blood chamber; means defining a blood inlet; means defining a blood outlet; a first semipermeable membrane means within said dialysate chamber for sterilizing and depyrogenating dialysate prior to its contact with blood; and a second semipermeable membrane means within said blood chamber for the removal of wastes from blood.

Claim 3

The hemodiafiltration cartridge of claim 1 wherein the cartridge is generally tubular and has two ends, a first end and a second end, and where the dialysate inlet is located at or adjacent to the first end of said cartridge, the dialysate outlet is located at or adjacent to the second end of said cartridge, the blood inlet is located at or adjacent to the second end of said cartridge, and the blood outlet is located at or adjacent to the first end of said cartridge.

Claim 4

The hemodiafiltration cartridge of claim 2 wherein said second semipermeable membrane means comprises a plurality of semipermeable hollow fibers, all of said hollow fibers being open at both ends, said plurality of semipermeable hollow fibers extending generally longitudinally through said cartridge from said first end of said cartridge to said second end of said cartridge, the plurality of semipermeable hollow fibers having two ends, one end being in communication with the blood inlet and the other end being in communication with the blood outlet and said first semipermeable membrane means comprises a plurality of semipermeable hollow fibers, all of said hollow fibers being open at the same end and being closed at the opposite end, said plurality of semipermeable hollow fibers extending generally longitudinally in said cartridge from said first end of said cartridge towards the second end of said cartridge, said open ends of said hollow fibers of the first semipermeable membrane means extending to the first end of said cartridge and being in communication with the dialysate inlet in order for dialysate to be able to flow into said hollow fibers.

Claim 5

The hemodiafiltration cartridge of claim 3 wherein the plurality of semipermeable hollow fibers of said first semipermeable membrane means extend generally longitudinally in said cartridge from said first end of said cartridge towards the second end of said cartridge but do not reach the second end of said cartridge and wherein the hemodiafiltration cartridge further comprises a plenum extending generally longitudinally from said closed ends of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge, said plenum being in communication with the dialysate outlet.

Claim 6

The hemodiafiltration cartridge of claim 4 wherein the first end of the cartridge is defined by a first end wall having openings for the dialysate inlet and the blood outlet; the second end of the cartridge is defined by a second end wall having openings for the dialysate outlet and the blood inlet; the cartridge has two generally cylindrical chambers, said blood chamber and said dialysate chamber, said blood chamber containing the second semipermeable membrane means and said dialysate chamber containing the first semipermeable membrane means and the plenum extending from the closed ends of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge, the dialysate inlet being located on the portion of the first end wall of the cartridge which bounds the dialysate chamber, the dialysate outlet being located on the portion of the second end wall of the cartridge which bounds the dialysate chamber, the blood inlet being located on the portion of the second end wall of the cartridge which bounds the blood chamber and the blood outlet being located on the portion of the first end wall of the cartridge which bounds the blood chamber and wherein said hemodiafiltration cartridge further comprises a first separating means which separates said blood chamber and dialysate chamber at the first end of the cartridge and a second separating means which separates said blood chamber and dialysate cnamber at the second end of the cartridge.

Claim 7

The hemodiafiltration cartridge of claim 5 wherein the dialysate chamber and the blood chamber are partially separated from each other in the interior of the cartridge by a first barrier means extending substantially longitudinally in said cartridge from said closed ends of the hollow fibers of the first semipermeable membrane means towards said first end of said cartridge but not reaching the first end of said cartridge, the space from the end of the first barrier means to the first end of the cartridge serving to allow dialysate to flow from said dialysate chamber into said blood chamber.

Claim 8

The hemodiafiltration cartridge of claim 6 wherein the plenum extending from said closed ends of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge is bounded by a second barrier means which extends laterally between said closed ends of the hollow fibers and said plenum.

Claim 9

The hemodiafiltration cartridge of claim 3 wherein the plurality of semipermeable hollow fibers of said first semipermeable membrane means extend generally longitudinally in said cartridge from said first end of said cartridge to said second end of said cartridge.

Claim 10

The hemodiafiltration cartridge of claim 2 wherein said second semipermeable membrane means comprises a plurality of semipermeable hollow fibers, all of said hollow fibers being open at both ends, said plurality of semipermeable hollow fibers extending generally longitudinally through said cartridge from said first end of said cartridge to said second end of said cartridge, said plurality of semipermeable hollow fibers having two ends, one end being in communication with the blood inlet and the other end being in communication with the blood outlet and said first semipermeable membrane means comprises a plurality of semipermeable hollow fibers, all of said hollow fibers being open at both ends, said plurality of semipermeable hollow fibers extending generally longitudinally in said cartridge from said first end of said cartridge towards the second end of said cartridge, said plurality of hollow fibers of the first semipermeable membrane means having two ends, a first bundle end and a second bundle end, the first bundle end extending to the first end of said cartridge and being in communication with the dialysate inlet in order for dialysate to be able to flow into said hollow fibers, said second bundle end being in communication with the outside of the cartridge via a tiny opening.

Claim 11

The hemodiafiltration cartridge of claim 9 wherein the plurality of semipermeable hollow fibers of said first semipermeable membrane means extend generally longitudinally in said cartridge from said first end of said cartridge towards the second end of said cartridge but do not reach the second end of said cartridge and wherein the hemodiafiltration cartridge further comprises a plenum extending generally longitudinally from said second bundle end of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge, said plenum being in communication with the dialysate outlet and said plenum being bounded by a second barrier means which extends laterally between said second bundle end and said plenum, said tiny opening through which the second bundle end is in communication with the outside of te cartridge being located in said second barrier means so that air and a minimal amount of dialysate can pass from the hollow fibers of the first semipermeable membrane means into said plenum via said tiny opening in the second barrier means and then out of said cartridge via said dialysate outlet.

Claim 12

The hemodiafiltration cartridge of claim 10 wherein the first end of the cartridge is defined by a first end wall having openings for the dialysate inlet and the blood outlet; the second end of the cartridge is defined by a second end wall having openings for the dialysate outlet and the blood inlet; the cartridge has two generally cylindrical chambers, said blood chamber and said dialysate chamber, said blood chamber containing the second semipermeable membrane means and said dialysate chamber containing the first semipermeable membrane means and the plenum extending from the second bundle end of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge, the dialysate inlet being located on the portion of the first end wall of the cartridge which bounds the dialysate chamber, the dialysate outlet being located on the portion of the second end wall of the cartridge which bounds the dialysate chamber, the blood inlet being located on the portion of the second end wall of the cartridge which bounds the blood chamber and the blood outlet being located on the portion of the first end wall of the cartridge which bounds the blood chamber and wherein said hemodiafiltration cartridge further comprises a first separating means which separates said blood chamber and dialysate chamber at the first end of the cartridge and a second separating means which separates said blood chamber and dialysate chamber at the second end of the cartridge.

Claim 13

The hemodiafiltration cartridge of claim 11 wherein both the first and second separatng means comprise an O-ring.

Claim 14

The hemodiafiltration cartridge of claim 11 wherein the dialysate chamber and the blood chamber are partially separated from each other in the interior of the cartridge by a first barrier means extending substantially longitudinally in said cartridge from said second bundle end of the hollow fibers of the first semipermeable membrane means towards said first end of said cartridge but not reaching the first end of said cartridge, the space from the end of the first barrier means to the first end of the cartridge serving to allow dialysate to flow from said dialysate chamber into said blood chamber.

Claim 15

The hemodiafiltration cartridge of claim 9 wherein the plurality of semipermeable hollow fibers of said first semipermeable membrane means and the plurality of semipermeable hollow fibers of said second semipermeable membrane means can be made from the same material or a different material, said material being selected from the group consisting of polysulfone, polyamide, polyacrylonitrile and cellulose acetate.

Claim 16

The hemodiafiltration cartridge of claim 9 wherein the semipermeable hollow fibers of said first semipermeable membrane means have molecular weight pore size cutoffs of at least 1000 daltons.

Claim 17

The hemodiafiltration cartridge of claim 9 wherein the semipermeable hollow fibers of said second semipermeable membrane means have molecular weight pore size cutoffs of up to 55,000 daltons.

Claim 18

The hemodiafiltration cartridge of claim 9 wherein the packing density of the semipermeable hollow fibers of said first semipermeable membrane means is between about 30% and about 70%.

Claim 19

The hemodiafiltration cartridge of claim 9 wherein the packing density of the semipermeable hollow fibers of said second semipermeable membrane means is between about 30% and about 70%.

Claim 20

A hemodiafiltration apparatus comprising; the hemodiafiltration cartridge of claim 2; a dialysate reservoir; first conduit means connecting said dialysate reservoir to said dialysate inlet of said cartridge; first conveying means for passing dialysate from said dialysate r--servoir through the first conduit means into said cartridge via said dialysate inlet and out of said cartridge via said dialysate outlet; second conduit means connecting a blood stream to said blood inlet of said cartridge; third conduit means connecting said blood outlet of said cartridge to said blood stream; and second conveying means for passing blood from said blood stream through the second conduit means into said cartridge via said blood inlet and for passing treated blood out of said cartridge to said blood stream via said blood outlet and via said third conduit means connecting said blood outlet to said blood stream.

Claim 21

A hemodiafiltration apparatus comprising; the hemodiafiltration cartridge of claim 7; a dialysate reservoir; first conduit means connecting said dialysate reservoir to said dialysate inlet of said cartridge; first conveying means for passing dialysate from said dialysate reservoir through the first conduit means into said cartridge via said dialysate inlet and out of said cartridge via said dialysate outlet; second conduit means connecting a blood stream to said blood inlet of said cartridge; third conduit means connecting said blood outlet of said cartridge to said blood stream; and second conveying means for passing blood from said blood stream through the second conduit means into said cartridge via said blood inlet and for passing treated blood out of said car ridge to said blood stream via said blood outlet and via said third conduit means connecting said blood outlet to said blood stream.

Claim 22

A hemodiafiltration apparatus comprising: the hemodiafiltration cartridge of claim 13; a dialysate reservoir; first conduit means connecting said dialysate reservoir to said dialysate inlet of said cartridge; first conveying means for passing dialysate from said dialysate reservoir through the first conduit means into said cartridge via said dialysate inlet and out of said cartridge via said dialysate outlet; second conduit means connecting a blood stream to said blood inlet of said cartridge; third conduit means connecting said blood outlet of said cartridge to said blood stream; and second conveying means for passing blood from said blood stream through the second conduit means into said cartridge via said blood inlet and for passing treated blood out of said cartridge to said blood stream via said blood outlet and via said third conduit means connecting said blood outlet to said blood stream.

Claim 23

A hemodiafiltration method comprising the steps of: (a) providing the hemodiafiltration cartridge of claim 3; (b) passing dialysate through the dialysate inlet into said hollow fibers of the first semipermeabe membrane means and through the walls of the hollow fibers of the first semipermeable membrane means, a portion of said dialysate entering into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means and the remainder of the dialysate surrounding the exterior of the hollow fibers of the second semipermeable membrane means; passing blood through the blood inlet and into said hollow fibers of the second semipermeable membrane means; (d) passing blood wastes and blood plasma water through the walls of the hollow fibers of the second semipermeable membrane means into said dialysate surrounding the second semipermeable membrane means; (e) pa sing the blood minus the blood wastes and blood plasma water in the hollow fibers of the second semipermeable membrane means together with the dialysate in the hollow fibers of the second semipermeable membrane means into the blood outlet; and (f) passing dialysate surrounding the second semipermeable membrane means with the blood wastes and blood plasma water lost from the blood into the dialysate outlet.

Claim 24

The method of claim 22 wherein the flow direction of the blood in the hollow fibers of the second semipermeable membrane means from .ntroducution to withdrawal is substantially opposit to the flow direction of the dialysate which has passed through the walls of the hollow fibers of the first semipermeable membrane means.

Claim 25

A hemodiafiltration method comprising the steps of: (a) providing the hemodiafiltration cartridge of claim 7; (b) Passing dialysate through the dialysate inlet into said hollow fibers of the first semipermeable membrane means and through the walls of the hollow fibers of the first semipermeable membrane means into said blood chamber at the space from the end of the first barrier means to the first end of the carrridge, a portion of said dialysate entering into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means and the reminder of the dialysate surrounding the exterior of the hollow fibers of the second semipermeable membrane means and flowing from the first end of the cartridge to the second end of the cartridge; (c) passing blood through the blood inlet and into said hollow fibers of the second semipermeable membrane means; (d) passing blood wastes and blood plasma water through the walls of the hollow fibers of the second semipermeable membrane means into said dialysate surrounding the second semipermeable membrane means; (e) passing the blood minus the blood wastes and blood plasma water in the hollow fibers of the second semipermeable membrane means together with the dialysate in the hollow fibers of the second semipermeable membrane means into the blood outlet; and (f) passing dialysate surrounding the second semipermeable membrane means with the blood washes and blood plasma water lost from the blood into the dialysate outlet via the plenum extending from the closed ends of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge.

Claim 26

The method of claim 24 wherein the inlet pressure of the blood is greater than the outlet pressure of the dialysate and the inlet pressure of the dialysate is greater than the outlet pressure of the blood.

Claim 27

The method of claim 24 wherein the flow direction of the blood in the hollow fibers of the second semipermeable membrane means from introduction to withdrawal is substantially opposite to the flow direction of the dialysate in the blood chamber.

Claim 28

A hemodiafiltration method comprising the steps of: (a) providing the hemodiafiltration cartridge of claim 9: (b) passing dialysate through the dialysate inlet into said hollow fibers of the first semipermeable membrane means; (c) passing dialysate from the hollow fibers of the first semipermeable membrane means through the walls of the hollow fibers of the first semipermeable membrane means, a portion of said dialysate entering into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means and the remainder of the dialysate surrounding the exterior of the hollow fibers of the second semipermeable membrane means; (d) passing blood through the blood inlet and into said hollow fibers of the second semipermeable membrane means; (e) passing blood wastes and blood plasma water through the walls of the hollow fibers of the second semipermeable membrane means into said dialysate surrounding the second semipermeable membrane means; (f) passing the blood minus the blood wastes and blood plasma water in the hollow fibers of the second semipermeable membrane means together with the dialysate in the hollow fibers of the second semipermeable membrane means into the blood outlet; and (g) passing dialysate surrounding the second semipermeable membrane means with the blood wastes and blood plasma water lost from the blood into the dialysate outlet.

Claim 29

The merhod of claim 27 further comprising the step of passing air in the hollow fibers of the first semipermeable membrane means out of said cartridge via said tiny opening.

Claim 30

The met od of claim 28 wherein a minimal amount of dialysate in the h.llow fibers of the first semipermeable membrane passes with said air out of said cartridge via said tiny opening, the remainder of the dialysate which has entered into said hollow fibers of the first semipermeable membrane means through the dialysate inlet being passed through the walls of the hollow fibers of the first semipermeable membrane means in step (c).

Claim 31

The method of claim 28 wherein the inlet pressure of the blood is greater than the outlet pressure of the dialysate and the inlet pressure of the dialysate is greater than the outlet pressure of the blood.

Claim 32

The method of claim 28 wherein the dialysate passed into the dialylate inlet in step (b) is unsterile and the dialysate which has passed through the walls of the hollow fibers of the first semipermeable membrane means and into the hollow fibers of the second semipermeable membrane means through the walls of rhe hollow fibers of the second semipermeable membrane means in step (c) is sterile and non-pyrogenic.

Claim 33

The method of claim 28 wherein the flow direction of the blood in the hollow fibers of the second semipermeable membrane means from introduction to withdrawal is substantially opposite to the flow direction of the dialysate which has passed through the walls of the hollow fibers of the first semipermeable membrane means.

Claim 34

A hemodiafiltration method comprising the steps of: (a) providing the hemodiafiltration cartridge of claim 13; (b) passinq dialysate throuqh the dialysate inlet into said hollow fibers of the first sempermeable membrane means; (c) passing dialysate from the hollow fibers of the first semipermeable membrane means through the walls of the hollow fibers of the first semipermeable membrane means into said blood chamber at the space from the end of the first barrier means to the first end of the cartridge, a portion of said dialysate entering into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means and the remainder of the dialysate surrounding the exterior of the hollow fibers of the second semipermeable membrane means and flowing from the first end of the cartridge to the second end of the cartridge; (d) passing blood through the blood inlet and into said hollow fibers of the second semipermeable membrane means; (e) passing blood wastes and blood plasma water through the walls of the hollow fibers of the second semipermeable membrane means into said dialysate surrounding the second semipermeable membrane means; (f) passing the blood minus the blood wastes and blood plasma water in the hollow fibers of the second semipermeable membrane means together with the dialysate in the hollow fibers of the second semipermeable membrane means into the blood outlet; and (g) passing dialysate surrounding the second semipermeable membrane means with the blood wastes and blood plasma water lost from the blood into the dialysate outlet via the plenum extending from the second bundle end of the hollow fibers of the first semipermeable membrane means to the second end of the cartridge.

Claim 35

The method of claim 33 further comprising the step of passing air in the hollow fibers of the first semipermeable membrane means into said plenum via said tiny opening in the second barrier means and then out of said cartridge via said dialysate outlet.

Claim 36

The method of claim 34 wherein a minimal amount of dialysate in the hollow fibers of the first semipermeable membrane means passes with said air into said plenum via said tiny opening in the second barrier means and then out of said cartridge via the dialysate outlet, the remainder of the dialysate which has entered into said hollow fibers of the first semipermeable membrane means through the dialysate inlet being passed through the walls of the hollow fibers of the first semipermeable membrane means in step (c).

Claim 37

The method of claim 35 wherein the minimal amount of dialysate comprises less than 10 percent of the dialysate which has entered into the hollow fibers of the first semipermeable membrane means via the dialysate inlet.

Claim 38

The method of claim 36 wherein the minimal amount of dialysate comprises less than 5 percent of the dialysate which has entered into the hollow fibers of the first semipermeable membrane means via the dialysate inlet.

Claim 39

The method of claim 34 wherein the inlet pressure of the blood is greater than the outlet pressure of the dialysate and the inlet pressure of the dialysate is greater than the outlet pressure of the blood.

Claim 40

The method of claim 34 wherein the flow direction of the blood in the hollow fibers of the second semipermeable membrane means from introduction to withdrawal is substantially opposite to the flow direction of the dialysate in the blood chamber.

Claim 41

The method of claim 34 wherein the dialysate passed into the dialysate inlet in step (b) is unsterile and the dialysate which has passed through the walls of the hollow fibers of the first semipermeable membrane means and into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means in step (c) is sterile and non-pyrogenic.

Claim 42

The method of claim 40 wherein the amount of dialysate entering into the hollow fibers of the second semipermeable membrane means through the walls of the hollow fibers of the second semipermeable membrane means is regulated.

Claim 43

The method of claim 41 wherein said regulation of the amount of dialysate occurs by adjusting the outlet pressure of the dialysate or the outlet pressure of the blood or both.