Method and device for supplying ready-to-use dialysis fluid

• US 6,607,697 B1
• Filed: 01/19/1999
• Issued: 08/19/2003
• Est. Priority Date: 01/19/1998
• Status: Expired due to Term

• Current Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius Medical Care AG)
• Original Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius Medical Care AG)
• Inventors: Müller, Carsten
• Primary Examiner(s): Sykes, Angela D.
• Assistant Examiner(s): Bianco, Patricia
• Application Number:
  US09/232,521
• Time in Patent Office: 1,673 Days
• Field of Search: 604/4-5, 604/28-31, 604/5-2-, 604/6.09, 604/6.1, 604/6.11, 210/646-47, 210/650, 210/653, 210/739, 210/742, 210/746, 210/321.65, 210/321.71, 210/929, 210/96.1, 210/96.2, 210/257.1, 210/257.2, 210/321.6, 210/321.72, 210/348, 210/420, 422/44-48
• US Class Current: 422/44
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/1664 with temperature control
• 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 1/3465 using dialysate as substitution fluid
• CPC Class Codes: A61M 2205/7554 with means for unclogging or regenerating filters
• CPC Class Codes: Y10S 210/929 Hemoultrafiltrate volume measurement or control processes

Abstract

A method of supplying ready-to-use dialysis fluid in a machine for extracorporeal blood treatment, is described, said machine having, in addition to a dialyzer, at least one sterile filter divided by a microbe-retaining membrane into a first and second chamber. The temperature and/or conductivity of the dialysis fluid flowing through the sterile filter is monitored. To prevent dialysis fluid whose temperature and/or conductivity does not correspond to a preset temperature and/or conductivity value from flowing out of the second chamber of the sterile filter into the dialyzer after rinsing off the membrane of the sterile filter, the dialysis fluid flowing out of the sterile filter is first removed into the drain through a bypass line until the proper values are established. Only then is the dialyzer connected to the dialysis fluid path. In addition, the invention relates to a machine for extracorporeal blood treatment with a device for supplying ready-to-use dialysis fluid.

Claims

1. A method of supplying ready-to-use dialysis fluid in extracorporeal blood treatment, comprising the steps of:

(a) providing blood to be treated to an extracorporeal blood treatment machine having;

a dialyzer divided by a semipermeable membrane into a dialysis fluid chamber connected to a dialysis fluid path and having a dialysis fluid chamber inlet and a dialysis fluid chamber outlet and a blood chamber connected to a blood path, the dialysis fluid path having a dialysis fluid inlet line and a dialysis fluid outlet line;

a fluid filter provided in the dialysis fluid path, the fluid filter divided by a microbe-retaining membrane into a first filter chamber and a second filter chamber, the first filter chamber having an inlet and each filter chamber having an outlet;

a first bypass line, having a first bypass valve and providing fluid connection between the first filter chamber outlet and the dialysis fluid outlet line;

a second bypass line, having a second bypass valve and providing fluid connection between the dialysis fluid inlet line and the dialysis fluid outlet line;

a measuring device provided in the dialysis fluid outlet line downstream of the first bypass line, the measuring device capable of measuring a dialysis fluid parameter selected from the group consisting of temperature and conductivity, and of generating a signal in response to the measured parameter; and

a comparing device connected to the measuring device arranged and composed for receiving a signal from the measuring device and calculating the difference between the measured dialysis fluid parameter and a predetermined value for the parameter;

(b) providing fresh dialysis fluid with the first bypass valve open, such that fluid flows through the first filter chamber into the first bypass line;

(c) closing the first bypass valve and opening the second bypass valve such that fluid flows through the microbe retaining membrane into the second filter chamber, out the second filter chamber outlet through the second bypass line into the dialysis fluid outlet line and through the measuring device;

(d) measuring the dialysis fluid parameter;

(e) comparing the measured value for the parameter and a predetermined value for the parameter; and

(f) closing the second bypass valve when the calculated difference is outside a pre-set limit value, such that dialysis fluid flows to the dialysis fluid chamber.

2. The method of claim 1, wherein opening the second bypass valve interrupts fluid flow to the dialysis fluid chamber.

3. The method of claim 1, wherein the extracorporeal blood treatment device further comprises a second measuring device adapted to measure a dialysis fluid parameter selected from the group consisting of temperature and conductivity, the second measuring device further adapted to generate a signal, the second measuring device provided in the dialysis fluid inlet line upstream of the second bypass line;

and

wherein the comparing device is connected to the second measuring device;

wherein step (d) of the method further comprises the steps of measuring the dialysis fluid parameter with the second measuring device and generating a signal; and

wherein step (e) of the method further comprises the steps of calculating the difference between the second measured value and the predetermined value.

4. The method of claim 1, wherein the extracorporeal blood treatment device further comprises a second measuring device adapted to measure a dialysis fluid parameter selected from the group consisting of temperature and conductivity, the second measuring device further adapted to generate a signal, the second measuring device provided in the dialysis fluid path upstream of the fluid filter;

and

wherein the comparing device is connected to the second measuring device;

wherein step (d) of the method further comprises the steps of measuring the dialysis fluid parameter with the second measuring device and generating a signal; and

wherein step (e) of the method further comprises the steps of calculating the difference between the second measured value and the predetermined value.

5. The method of claim 1, wherein the dialysis fluid inlet line further comprises:

a shutoff valve downstream of the second bypass line, the shutoff valve connected to the control device;

wherein;

step (c) of the method further comprises closing the shutoff valve; and

step (f) of the method further comprises opening the inlet line valve.

6. A method of supplying ready-to-use dialysis fluid in extracorporeal blood treatment, comprising the steps of:

(a) providing blood to be treated to an extracorporeal blood treatment machine having;

a dialyzer divided by a semipermeable membrane into a dialysis fluid chamber connected to a dialysis fluid path and having a dialysis fluid chamber inlet and a dialysis fluid chamber outlet and a blood chamber connected to a blood path, the dialysis fluid path having a dialysis fluid inlet line and a dialysis fluid outlet line;

a fluid filter provided in the dialysis fluid path, the fluid filter divided by a microbe-retaining membrane into a first filter chamber and a second filter chamber, the first filter chamber having an inlet and each filter chamber having an outlet;

a first bypass line, having a first bypass valve and providing fluid connection between the first filter chamber outlet and the dialysis fluid outlet line;

a second bypass line, having a second bypass valve and providing fluid connection between the dialysis fluid inlet line and the dialysis fluid outlet line;

a measuring device provided in the dialysis fluid outlet line downstream of the first bypass line, the measuring device capable of measuring a dialysis fluid parameter selected from the group consisting of temperature and conductivity, and of generating a signal in response to the measured parameter; and

a comparing device connected to the measuring device arranged and composed for receiving a signal from the measuring device and calculating the difference between the measured dialysis fluid parameter and a predetermined value for the parameter;

(b) providing fresh dialysis fluid to the dialysis fluid path with the first and second bypass valves closed such that fluid flows through the fluid filter and the dialysis inlet line into the dialysis fluid chamber, through the dialysis fluid outlet line and the measuring device and into the drain;

(c) taking a first measurement of the dialysis fluid parameter;

(d) opening the first bypass valve in response to a calculated difference exceeding a pre-set value, thereby diverting dialysis fluid through the first bypass line into the dialysis fluid outline line;

(e) taking a second measurement of the dialysis fluid parameter;

(f) closing the first bypass valve in response to a calculated value falling below the pre-set value, thereby interrupting flow through the first bypass line; and

(g) opening the second bypass valve, thereby allowing fluid flow through the second bypass line into the dialysis fluid outline line.

7. The method of claim 6, wherein the method further comprises the steps of:

(h) taking a third measurement of the dialysis fluid parameter; and

(i) closing the second bypass valve in response to a calculated value falling below the pre-set value.

8. A device for extracorporeal blood treatment comprising:

a dialyzer divider by a semipermeable membrane into a dialysis fluid chamber connected to a dialysis fluid path and having,a dialysis fluid chamber inlet and a dialysis fluid chamber outlet and a blood chamber connected to a blood path, the dialysis fluid path having a dialysis fluid inlet line and a dialysis fluid outlet line;

a fluid filter provided in the dialysis fluid path, the fluid filter divided by a microbe-retaining membrane into a first filter chamber and a second filter chamber, the first filter chamber having an inlet and each filter chamber having an outlet;

a first bypass line, having a first bypass valve and providing fluid connection between the first filter chamber outlet and the dialysis fluid outlet line;

a second bypass line, having a second bypass valve and providing fluid connection between the dialysis fluid inlet line and the dialysis fluid outlet line, the second bypass line being in fluid communication with the second filter chamber of the fluid filter;

a measuring device provided in the dialysis fluid outlet line downstream of the first bypass line, the measuring device capable of measuring a dialysis fluid parameter selected from the group consisting of temperature and conductivity, and of generating a signal in response to the measured parameter; and

a comparing device connected to the measuring device arranged and composed for receiving a signal from the measuring device and calculating the difference between the measured dialysis fluid parameter and a predetermined value for the parameter;

wherein closing the first bypass valve and opening the second bypass valve diverts dialysis fluid through the second bypass line into the dialysis fluid outlet line and closing the second bypass valve allows dialysis fluid flow to the dialysis fluid chamber; and

wherein a control device opens the second bypass valve when the first bypass valve is closed and closes the second bypass valve when the calculated difference falls below a pre-set limit value.

9. The device of claim 8, wherein the device further comprises an inlet shutoff valve provided in the dialysis fluid inlet line, the inlet shutoff valve being connected to the control device;

wherein the control device closes the inlet shutoff valve when the second bypass valve is opened and opens the inlet shutoff valve when the second bypass valve is closed.

10. The device of claim 9, wherein the device further comprises an outlet shutoff valve provided in the dialysis fluid outlet line, the outlet shutoff valve being connected to the control device;

wherein the control device closes the outlet shutoff valve when the second bypass valve is opened and opens the outlet shutoff valve when the second bypass valve is closed.

11. The device of claim 10, wherein the control device opens the first bypass valve when the calculated difference in the pre-set limit value.

12. The device of claim 11, wherein the control device closes the first bypass valve, opens the second bypass valve and closes the inlet and outlet shutoff valves when the calculated difference falls below the pre-set limit value.

13. The device of claim 12, wherein the control device closes the second bypass valve and opens the inlet and outlet shutoff valves when the calculated value falls below the preset limit value.

14. The device of claim 8, wherein the device further comprises a second measuring device provided in the dialysis fluid inlet line upstream of the second bypass line and connected to the comparing device, the second measuring device adapted for measuring a dialysis fluid parameter selected from the group consisting of temperature and conductivity.

15. The device of claim 8, wherein the device further comprises a second measuring device provided in the dialysis fluid path upstream of the fluid filter and connected to the comparing device, the second measuring device adapted for measuring a dialysis fluid parameter selected from the group consisting of temperature and conductivity.