METHOD AND DEVICE FOR THE MEASUREMENT AND THE ELIMINATION OF SYSTEM CHANGES IN A DEVICE FOR THE TREATMENT OF BLOOD

• US 20130211730A1
• Filed: 10/14/2011
• Published: 08/15/2013
• Est. Priority Date: 10/14/2010
• Status: Active Grant

• Current Assignee: B. Braun Avitum AG (B. Braun Holding GmbH & Co. KG)
• Original Assignee: B. Braun Avitum AG (B. Braun Holding GmbH & Co. KG)
• Inventors: Wolff, Henrik
• Granted Patent: US 9,400,199 B2
• Time in Patent Office: Days
• US Class Current: 702/19
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 2205/702 automatically during use
• CPC Class Codes: A61M 2205/707 Testing of filters for clogging
• CPC Class Codes: G01F 1/74 Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture

Abstract

The present invention relates to a method and a device for the measurement of pressure signals in a blood treatment system, whereby system changes can be identified and can be differentiated additionally reliably between system changes in blood flow direction and in transmembrane direction in order to enable a targeted action.

Claims

1-14. -14. (canceled)

15. Method for the differentiation of disturbances of the flow resistance in a blood treatment system which comprises the following steps:

a) measuring at least two pressure signals selected from the group consisting of (PB1, PB2, PD1, PD2), which are measured at at least two pressure sensors, which are selected from the group consisting of [PB1], [PB2], [PD1] and [PD2], wherein [PB1] represents the pressure sensor in the blood circulation before the blood inlet into the tangential flow filter TFF and PB1 represents the pressure measured at the pressure sensor [PB1], [PB2] represents the pressure sensor in the blood circulation after the blood outlet from the tangential flow filter TFF and PB2 represents the pressure measured at the pressure sensor [PB2], [PD1] represents the pressure sensor in the dialysate circulation before the dialysate inlet into the tangential flow filter TFF and PD1 represents the pressure measured at the pressure sensor [PD1] and [PD2] represents the pressure sensor in the dialysate circulation after the dialysate outlet from the tangential flow filter TFF and PD2 represents the pressure measured at the pressure sensor [PD2];

b) calculating the quotients and/or the differences from the pressure signals measured according to step a), wherein the quotients and/or the differences are calculated from the pressure signals selected from the group consisting of (PB1, PB2) and/or (PB1, PD1) and/or (PB1, PD2) and/or (PB2, PD1) and/or (PB2, PD2) and/or (PD1, PD2) and/or (PB1, PDM) and/or (PB2, PDM) and/or (PD1, PBM) and/or (PD2, PBM) and/or (PDM, PBM) in a central processing unit, wherein with PBM or PDM the respective average from (PB1,PB2) or (PD1, PD2) is represented;

c) at least one time offset repeating of the steps a) and b), wherein at the same at least two pressure sensors as measured in the previous measurement and from the measured pressure signals the same quotients and/or differences are calculated;

d) generating at least one time trend from the measured pressure signals selected from the group consisting of (PB1, PB2, PD1, PD2) and/or the calculated differences, and/or quotients of the pressure signals (PB1, PB2) and/or (PB1, PD1) and/or (PB1, PD2) and/or (PB2, PD1) and/or (PB2, PD2) and/or (PD1, PD2) and/or (PB1, PDM) and/or (PB2, PDM) and/or (PD1, PBM) and/or (PD2, PBM) and/or (PDM, PBM);

e) evaluating the at least one time trend, whether a change of the at least one time trend has occurred over a tolerance range;

f) generating a pattern for the evaluation of the at least one time trend;

g) assigning the pattern to a disturbance condition; and

h) displaying the disturbance on a display device of the central processing unit.

16. Method according to claim 15, wherein the at least two pressure signals can be respectively absolute pressures, relative pressures, absolute pressure differences between two pressure measuring points, relative pressure differences between two pressure measuring points, absolute pressure amplitudes, relative pressure amplitudes, differences between the absolute pressure amplitudes at two pressure measuring points, or differences between the relative pressure amplitudes at two pressure measurement points or a combination thereof.

17. Method according to claim 15, wherein the at least two pressure signals are determined respectively from the analysis of the frequency spectrum of the blood flow.

21. A blood treatment system which comprises a blood treatment unit and at least two pressure sensors which are selected from the group consisting of [PB1], [PB2], [PD1] and [PD2], wherein [PB1] represents the pressure sensor in the blood circulation before the blood inlet into the tangential flow filter TFF, [PB2] represents the pressure sensor in the blood circulation after the blood outlet from the tangential flow filter TFF, [PD1] represents the pressure sensor in the dialysate circulation before the dialysate inlet into the tangential flow filter TFF, and [PD2] represents the pressure sensor in the dialysate circulation after the dialysate outlet from the tangential flow filter TFF and a central processing unit, wherein the at least two pressure sensors are connected with the central processing unit for the transmission of the measured values and the central processing unit is able to analyze and display the incoming measured values such that a differentiation of flow resistance changes in transmembrane direction and blood flow direction in the blood treatment unit is possible by one of the methods according to claim 15.

22. The blood treatment system according to claim 21, which comprises additionally an ultrafiltration pump and a balance chamber system.

23. The blood treatment system according to claim 21, in which the pressure sensors [PB1], [PB2], [PD1] and [PD2] have respectively a sampling rate of at least 20 Hz.

24. The blood treatment system according to claim 22, in which the pressure sensors [PB1], [PB2], [PD1] and [PD2] have respectively a sampling rate of at least 20 Hz.

25. A blood treatment system according to claim 21, wherein the at least two pressure signals can be respectively absolute pressures, relative pressures, absolute pressure differences between two pressure measuring points, relative pressure differences between two pressure measuring points, absolute pressure amplitudes, relative pressure amplitudes, differences between the absolute pressure amplitudes at two pressure measuring points, or differences between the relative pressure amplitudes at two pressure measurement points or a combination thereof.

26. A blood treatment system according to claim 21, wherein the at least two pressure signals are determined respectively from the analysis of the frequency spectrum of the blood flow.

18. Method for the differentiation of disturbances of the flow resistance in a blood treatment system, which comprises the following steps:

a) time offset measuring of each of at least two pressure signals at at least two pressure sensors,

wherein the pressure signals are selected from the group consisting of PB1, PB2, PD1 and PD2, the pressure sensors are selected from the group consisting of [PB1], [PB2], [PD1] and [PD2],

[PB1] represents the pressure sensor in the blood circulation before the blood inlet into the tangential flow filter TFF and PB1 represents the pressure measured at the pressure sensor [PB1],

[PB2] represents the pressure sensor in the blood circulation after the blood outlet from the tangential flow filter TFF and PB2 represents the pressure measured at the pressure sensor [PB2],

[PD1] represents the pressure sensor in the dialysate circulation before the dialysate inlet into the tangential flow filter TFF and PD1 represents the pressure measured at the pressure sensor [PD1], and

[PD2] represents the pressure sensor in the dialysate circulation after the dialysate outlet from the tangential flow filter TFF and PD2 represents the pressure measured at the pressure sensor [PD2];

b) calculating of at least two quotients and/or differences from the pressure signals measured time offset according to step a) at the same pressure sensor in a central processing unit,

wherein the quotients calculated in such a manner according to the pressure sensor, at which the measurement has been carried out, are represented as Q[PB1], Q[PB2], Q[PD1] and Q[PD2] and the differences as Δ

[PB1], Δ

[PB2], Δ

[PD1] and Δ

[PD2];

c) calculating at least one quotient and/or at least one difference in the central processing unit from the quotients and/or differences calculated according to step b),

wherein the quotients and/or the differences are selected from the group consisting of

(Q[PB1], Q[PB2]) and/or (Q[PB1], Q[PD1]) and/or (Q[PB1], Q[PD2]) and/or (Q[PB2], Q[PD1]) and/or (Q[PB2], Q[PD2]) and/or (Q[PD1], Q[PD2]) and/or (Δ

[PB1], Δ

[PB2]) and/or (Δ

[PB1], Δ

[PD1]) and/or (Δ

[PB1], Δ

[PD2]) and/or (Δ

[PB2], Δ

[PD1]) and/or (Δ

[PB2], Δ

[PD2]) and/or (Δ

[PD1], Δ

[PD2]) and/or (Q[PB1], (Δ

[PB1]) and/or (Q[PB1], (Δ

[PB2]) and/or (Q[PB1], (Δ

[PD1]) and/or (Q[PB1], (Δ

[PD2]) and/or (Q[PB2], (Δ

[PB1]) and/or (Q[PB2], (Δ

[PB2]) and/or (Q[PB2], (Δ

[PD1]) and/or (Q[PB2], (Δ

[PD2]) and/or (Q[PD1], (Δ

[PB1]) and/or (Q[PD1], (Δ

[PB2]) and/or (Q[PD1], (Δ

[PD1]) and/or (Q[PD1], (Δ

[PD2]) and/or (Q[PD2], (Δ

[PB1]) and/or (Q[PD2], (Δ

[PB2]) and/or (Q[PD2], (Δ

[PD1]) and/or (Q[PD2], (Δ

[PD2]) and/or (Q[PB1], Q[PBM]) and/or (Q[PB2], Q[PBM]) and/or (Q[PD1], Q[PBM]) and/or (Q[PD2], Q[PBM]) and/or (Δ

[PB1], Q[PBM]) and/or (Δ

[PB2], Q[PBM]) and/or (Δ

[PD1], Q[PBM]) and/or (Δ

[PD2], Q[PBM]) and/or (Q[PB1], Q[PDM]) and/or (Q[PB2], Q[PDM]) and/or (Q[PD1], Q[PDM]) and/or (Q[PD2], Q[PDM]) and/or (Δ

[PB1], Q[PDM]) and/or (Δ

[PB2], Q[PDM]) and/or (Δ

[PD1], Q[PDM]) and/or (Δ

[PD2], Q[PDM]) and/or (Q[PB1], Δ

[PBM]) and/or (Q[PB2], Δ

[PBM]) and/or (Q[PD1], Δ

[PBM]) and/or (Q[PD2], Δ

[PBM]) and/or (Δ

[PB1], Δ

[PBM]) and/or (Δ

[PB2], Δ

[PBM]) and/or (Δ

[PD1], Δ

[PBM]) and/or (Δ

[PD2], Δ

[PBM]) and/or (Q[PB1], Δ

[PDM]) and/or (Q[PB2], Δ

[PDM]) and/or (Q[PD1], Δ

[PDM]) and/or (Q[PD2], Δ

[PDM]) and/or (Δ

[PB1], Δ

[PDM]) and/or (Δ

[PB2], Δ

[PDM]) and/or (0[PD1], Δ

[PDM]) and/or (Δ

[PD2], Δ

[PDM]) and/or (Q[PBM], Q[PDM]) and/or (Q[PBM], Δ

[PBM]) and/or (Q[PBM], Δ

[PDM]) and/or (Q[PDM], Δ

[PBM]) and/or (Q[PDM], Δ

[PDM]) and/or (Δ

[PBM], Δ

[PDM]) and

wherein Q[PBM] represents the average from Q[PB1] and Q[PB2], Q[PDM] represents the average from Q[PD1] and Q[PD2], Δ

[PBM] represents the average from Δ

[PB1] and Δ

[PB2], Δ

[PDM] represents the average from Δ

[PD1] and Δ

[PD2];

d) at least one time offset repeating of the steps a), b) and c), wherein at the same at least two pressure sensors as measured in the previous measurement and from the measured pressure signals the same quotients and/or differences are calculated;

e) generating at least one time trend from the measured pressure signals selected from the groups listed in c);

f) evaluating the at least one time trends, whether a change of the at least one time trend has occurred over a tolerance range;

g) generating a pattern for the evaluation of the at least one time trend;

h) assigning of the pattern to a disturbance condition; and

i) displaying the disturbance on a display device of the central processing unit.

19. Method according to claim 18, wherein the at least one pressure signal can be respectively an absolute pressure, a relative pressure, an absolute pressure difference between two pressure measuring points, a relative pressure difference between two pressure measuring points, an absolute pressure amplitude, a relative pressure amplitude, a difference between the absolute pressure amplitudes at two pressure measuring points, or a difference between the relative pressure amplitudes at two pressure measurement points or a combination thereof.

20. Method according to claim 19, wherein the at least one pressure signal is determined from the analysis of the frequency spectrum of the blood flow.

27. A blood treatment system which comprises a blood treatment unit and at least two pressure sensors which are selected from the group consisting of [PB1], [PB2], [PD1] and [PD2], wherein [PB1] represents the pressure sensor in the blood circulation before the blood inlet into the tangential flow filter TFF, [PB2] represents the pressure sensor in the blood circulation after the blood outlet from the tangential flow filter TFF, [PD1] represents the pressure sensor in the dialysate circulation before the dialysate inlet into the tangential flow filter TFF, and [PD2] represents the pressure sensor in the dialysate circulation after the dialysate outlet from the tangential flow filter TFF and a central processing unit, wherein the at least two pressure sensors are connected with the central processing unit for the transmission of the measured values and the central processing unit is able to analyze and display the incoming measured values such that a differentiation of flow resistance changes in transmembrane direction and blood flow direction in the blood treatment unit is possible by one of the methods according to claim 18.

28. The blood treatment system according to claim 27, which comprises additionally an ultrafiltration pump and a balance chamber system.

29. The blood treatment system according to claim 27, in which the pressure sensors [PB1], [PB2], [PD1] and [PD2] have respectively a sampling rate of at least 20 Hz.

30. The blood treatment system according to claim 28, in which the pressure sensors [PB1], [PB2], [PD1] and [PD2] have respectively a sampling rate of at least 20 Hz.

31. A blood treatment system according to claim 27, wherein the at least one pressure signal can be respectively an absolute pressure, a relative pressure, an absolute pressure difference between two pressure measuring points, a relative pressure difference between two pressure measuring points, an absolute pressure amplitude, a relative pressure amplitude, a difference between the absolute pressure amplitudes at two pressure measuring points, or a difference between the relative pressure amplitudes at two pressure measurement points or a combination thereof.

32. A blood treatment system according to claim 27, wherein the at least one pressure signal is determined from the analysis of the frequency spectrum of the blood flow.