HEMODIALYSIS SYSTEMS AND METHODS

• US 20090095679A1
• Filed: 08/27/2008
• Published: 04/16/2009
• Est. Priority Date: 02/27/2007
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Grant, Kevin L., Demers, Jason A., Dale, James D., Wilt, Michael J., Ballantyne, Todd A.
• Granted Patent: US 8,357,298 B2
• Time in Patent Office: Days
• US Class Current: 210/646
• CPC Class Codes: A61M 1/1524 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/154 with sensing means or components thereof
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/156 Constructional details of the cassette, e.g. specific details on material or shape
• CPC Class Codes: A61M 1/15625 the reservoirs acting as balance chambers
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1601 Control or regulation
• CPC Class Codes: A61M 1/1613 Profiling or modelling of patient or predicted treatment evolution or outcome
• CPC Class Codes: A61M 1/1635 with volume chamber balancing devices between used and fresh dialysis fluid
• CPC Class Codes: A61M 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 1/3434 with pre-dilution and post-dilution
• CPC Class Codes: A61M 1/3437 downstream of the filter, e.g. post-dilution with filtrate
• CPC Class Codes: A61M 1/3441 Substitution rate control as a function of the ultrafiltration rate
• CPC Class Codes: A61M 1/3465 using dialysate as substitution fluid
• CPC Class Codes: A61M 1/3609 Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36224 with sensing means or components thereof
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/36226 Constructional details of cassettes, e.g. specific details on material or shape
• CPC Class Codes: A61M 1/362265 : Details of valves
• CPC Class Codes: A61M 1/362266 : Means for adding solutions or substances to the blood
• CPC Class Codes: A61M 1/3623 : Means for actively controlling temperature of blood
• CPC Class Codes: A61M 1/3646 : Expelling the residual body fluid after use, e.g. back to the body
• CPC Class Codes: A61M 1/365 : through membranes, e.g. by inverted trans-membrane pressure [TMP]
• CPC Class Codes: A61M 1/3652 : using gas, e.g. air
• CPC Class Codes: A61M 2202/0413 : Blood
• CPC Class Codes: A61M 2205/12 : with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/18 : with alarm
• CPC Class Codes: A61M 2205/3317 : Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 : PH measuring means
• CPC Class Codes: A61M 2205/3331 : Pressure; Flow
• CPC Class Codes: A61M 2205/3334 : Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 : Temperature
• CPC Class Codes: A61M 2205/502 : User interfaces, e.g. screens or keyboards
• CPC Class Codes: F04B 45/0536 : the actuating fluid being controlled by one or more valves
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/63 : for local operation

Abstract

Hemodialysis dialysis systems are disclosed. Hemodialysis systems of the invention may include a dialysate flow path including a balancing circuit, a mixing circuit, and/or a directing circuit. The circuits may be defined within one or more cassettes. The fluid circuits may be at least partially isolated, spatially and/or thermally, from electrical components of the system. A gas supply may be provided in fluid communication with the dialysate flow path and/or the dialyzer to urge dialysate through the dialyzer and blood back to the patient. The hemodialysis systems may include fluid handling devices, actuated using a control fluid, optionally delivered using a detachable pump. Fluid handling devices may be generally rigid and of a spheroid shape, optionally with a diaphragm dividing the device into compartments.

Claims

1. A hemodialysis system comprising:

a dialysis unit comprising an automation computer and dialysis equipment;

a user interface unit comprising a user interface computer and a user interface, the user interface being adapted to display information and receive inputs;

wherein the automation computer is configured to receive requests for safety-critical information from the user interface computer, and the automation computer is configured to access the safety-critical information on behalf of the user interface computer; and

wherein the user interface computer is configured to display information related to a dialysis process via the user interface using the safety-critical information.

2. The hemodialysis system of claim 1, wherein the safety-critical information relates to a state of a display of the user interface, the state of the display being based, at least in part, on a state of the dialysis process.

3. The hemodialysis system of claim 1, wherein the safety-critical information comprises data collected from the dialysis process.

4. The hemodialysis system of claim 1, wherein the user interface computer is configured to receive an input specifying a display mode and to select, based on the specified display mode, a subset of the safety-critical information to use to display the information related to the dialysis process.

5. The hemodialysis system of claim 1, wherein:

the automation computer comprises an interface to the dialysis equipment;

the user interface computer is configured to receive an input relating to a requested dialysis process and transmit the input to the automation computer; and

the automation computer is configured to issue, in response to receipt of the input, a command to the interface to initiate the dialysis process.

6. The hemodialysis system of claim 5, wherein the automation computer is further configured to verify the input prior to issuing the command.

7. The hemodialysis system of claim 1, wherein the user interface computer is further configured to display information related to the dialysis process via the user interface using screen design information accessed directly by the user interface computer.

8. The hemodialysis system of claim 1, wherein the automation computer is configured to control all safety-critical information stored in the hemodialysis system.

9. The hemodialysis system of claim 1, wherein the hemodialysis system comprises a database for storing the safety-critical information, and wherein the automation computer is configured to control the storage of the safety-critical information to the database.

10. The hemodialysis system of claim 9, wherein the user interface computer is prevented from writing information to the database.

11. The hemodialysis system of claim 1, wherein the dialysis equipment comprises a mixing circuit, a blood flow circuit, a balancing circuit, and an external dialysate circuit.

12. The hemodialysis system of claim 1, wherein the automation computer is configured to trigger an alarm condition when an abnormal condition is detected by at least one sensor associated with the dialysis equipment.

13. The hemodialysis system of claim 12, wherein the user interface computer is configured to control a display of alarm information indicative of the alarm condition via the user interface.

14. A method of managing a user interface in a hemodialysis system, the method comprising:

receiving an input related to a dialysis process at a user interface associated with a user interface computer;

in response to the input, transmitting a request for safety-critical information from the user interface computer to an automation computer associated with dialysis equipment;

accessing the safety-critical information on behalf of the user interface computer; and

using the safety-critical information, displaying information related to the dialysis process via the user interface.

15. The method of claim 14, wherein the safety-critical information relates to a state of a display of the user interface, the state of the display being based, at least in part, on a state of the dialysis process.

16. The method of claim 14, wherein the safety-critical information comprises data collected from the dialysis process.

17. The method of claim 14, further comprising:

receiving an input specifying a display mode at the user interface; and

using the user interface computer, selecting a subset of the safety-critical information based on the specified display mode; and

displaying the subset of the safety-critical information via the user interface.

18. The method of claim 14, further comprising:

receiving an input relating to a requested dialysis process at the user interface;

transmitting the input from the user interface computer to the automation computer;

verifying the input; and

in response to verifying the input, commanding the dialysis equipment to initiate the dialysis process.

19. The method of claim 14, further comprising:

accessing screen design information stored within the user interface computer;

wherein displaying information related to the dialysis process via the user interface using the safety-critical information further comprises, using the screen design information, displaying information related to the dialysis process via the user interface.

20. Computer storage media encoded with instructions that, when executed, perform a method comprising acts of:

receiving, from a user interface associated with a user interface computer, an input related to a dialysis process;

in response to the input, transmitting a request for safety-critical information from the user interface computer to an automation computer associated with dialysis equipment;

accessing the safety-critical information on behalf of the user interface computer;

transmitting the safety-critical information to the user interface computer;

accessing screen design information stored within the user interface computer;

using the safety-critical information and the screen design information, causing the user interface to display information related to the dialysis process.

21. A pumping cassette, comprising:

at least one fluid inlet;

at least one fluid outlet;

a flow path connecting the at least one fluid inlet and the at least one fluid outlet, the flow path passing through a balancing chamber and a second fluid inlet connectable to a source of anticoagulant,

wherein fluid entering the at least one fluid inlet passes the second fluid inlet prior to entering the balancing chamber.

22. The pumping cassette of claim 21, wherein the spike is hollow.

23. A cassette, comprising:

a first flow path connecting a first inlet to a first outlet;

a second flow path connecting a second inlet to a second outlet;

a control fluid path;

at least two pumps, each pump comprising a rigid vessel containing a diaphragm dividing the rigid vessel into a first compartment and a second compartment, the first compartment of each pump being in fluidic communication with the control fluid path and the second compartment being in fluidic communication with the second flow path;

a balancing chamber able to balance flow between the first flow path and the second flow path; and

a control device able to open at least one valve directly controlling fluid within the balancing chamber using pulse-width modulation.

24. The cassette of claim 23, wherein the diaphragm is flexible.

25. A hemodialysis system, comprising:

a blood flow path through which untreated blood is drawn from a patient and passed through a dialyzer;

a dialysate flow path through which dialysate flows from a dialysate supply through the dialyzer, the dialysate flow path and the blood flow path being in fluidic communication; and

a pressure device able to urge dialysate in the dialysate flow path to flow into the blood flow path,

wherein pressure is controlled within the pressure device such that the pressure of the dialysate exiting the dialyzer is lower than the pressure of the blood exiting the dialyzer.

26. The hemodialysis system of claim 25, wherein the blood flow path is defined by a blood flow cassette.

27. The hemodialysis system of claim 25, wherein the dialysate flow path is defined by at least one cassette.

28. A hemodialysis system, comprising:

a blood flow path through which untreated blood is drawn from a patient and passed through a dialyzer;

a dialysate flow path through which dialysate flows from a dialysate supply through the dialyzer, the dialysate flow path and the blood flow path being in fluidic communication; and

a pressure device able to urge dialysate in the dialysate flow path to flow into the blood flow path,

wherein pressure is controlled within the pressure device such that the pressure of the dialysate entering the dialyzer is greater than the pressure of the blood entering the dialyzer.

29. The hemodialysis system of claim 28, wherein the blood flow path is defined by a blood flow cassette.

30. The hemodialysis system of claim 28, wherein the dialysate flow path is defined by at least one cassette.

31. A method, comprising:

providing a hemodialysis system, comprising;

a blood flow path through which blood is drawn from a patient and passed through a dialyzer; and

a dialysate flow path through which dialysate flows from a dialysate supply through the dialyzer, the dialysate flow path comprising;

a balancing cassette which controls the amount of dialysate passing through the dialyzer,

a mixing cassette which forms dialysate from water, and

a directing cassette which passes water from a water supply to the mixing cassette and passes dialysate from the mixing cassette to the balancing cassette; and

passing dialysate through the dialyzer such that dialysate is pushed through the dialyzer into the blood flow path and is pulled back with every dialysate pump stroke.

32. The method of claim 31, wherein the blood flow path is defined by a blood flow cassette.

33. The method of claim 31, wherein the dialysate flow path is defined by at least one cassette.