METHOD AND DEVICES FOR DETERMINING A TIME POINT FOR MEASURING PRESSURE MEASUREMENTS

Abstract

The present disclosure relates to a method for determining or recommending a time point for measuring a patient's pressure readings during a blood treatment session. The method encompasses monitoring the ultrafiltration rate with which the patient's blood is treated, a relative blood volume, and/or a sodium concentration or a change in any of these, for the existence of, or meeting any pre-determined criterion for the ultrafiltration, the relative blood volume, and/or the sodium concentration, or the change thereto. Furthermore, the method encompasses transmitting a signal to a blood pressure measuring device when the pre-determined criterion for the ultrafiltration rate, the relative blood volume, and/or the sodium concentration or the change thereto is met.

Claims

1-16. (canceled)

17. A method for determining or recommending at least one time point for measuring pressure measurements on a patient during a treatment session in which the patient's blood is treated extracorporeally via a blood treatment apparatus, the method comprising: monitoring, during the treatment session, one or more of an ultrafiltration rate with which the patient's blood is treated, a relative blood volume, and a sodium concentration for one or more changes in or for fulfilling one or more pre-determined criteria, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration; and transmitting a signal to a blood pressure measuring device when any of the one or more pre-determined criteria or any of the one or more changes are met, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration.

18. The method according to claim 17, wherein the patient's blood is treated extracorporeally via the blood treatment apparatus by carrying out an ultrafiltration process.

19. The method according to claim 17, wherein a pre-determined criterion for the ultrafiltration rate is met when a minimum value for the ultrafiltration rate or a change in the ultrafiltration rate is reached, exceeded, or set for a pre-determined duration.

20. The method according to claim 17, wherein a pre-determined criterion for the relative blood volume is met when the relative blood volume falls below a minimum value or when a change in the relative blood volume exceeds a maximum value.

21. The method according to claim 17, wherein a pre-determined criterion for the sodium concentration is met when the sodium concentration falls below a minimum value or when a maximum value for a change in the sodium concentration has been exceeded.

22. The method according to claim 21, wherein the pre-determined criterion for the sodium concentration is met when the sodium concentration falls below the minimum value in dialysis liquid or when the maximum value for the change in the sodium concentration in the dialysis liquid has been exceeded.

23. The method according to claim 17, wherein a change or a pre-determined criteria for the ultrafiltration rate, the relative blood volume, or the sodium concentration is met if a pre-determined event occurs or is reached during a blood treatment profile that is set on the blood treatment apparatus for the ultrafiltration rate, the relative blood volume, or the sodium concentration, respectively.

24. The method according to claim 17, wherein the signal transmitted to the blood pressure measuring device comprises a signal for preparing the blood pressure measuring device for a procedure for measuring blood pressure readings of the patient.

25. The method according to claim 24, wherein the procedure comprises inflating a blood pressure cuff of the blood pressure measuring device.

26. The method according to claim 17, wherein the signal transmitted to the blood pressure measuring device comprises a signal for measuring a patient's arterial blood pressure reading or venous blood pressure reading.

27. The method according to claim 17, wherein monitoring one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration comprises reading out of at least one treatment parameter or treatment profile that is set on the blood treatment apparatus and used during the blood treatment session.

28. A control device or closed-loop control device configured to carry out mechanical steps of a method for determining or recommending at least one time point for measuring pressure measurements on a patient during a treatment session in which the patient's blood is treated extracorporeally via a blood treatment apparatus, the method comprising: monitoring, during the treatment session, one or more of an ultrafiltration rate with which the patient's blood is treated, a relative blood volume, and a sodium concentration for one or more changes in or for fulfilling one or more pre-determined criteria, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration; and transmitting a signal to a blood pressure measuring device when any of the one or more pre-determined criteria or any of the one or more changes are met, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration.

29. The control device or closed-loop control device according to claim 28, wherein the patient's blood is treated extracorporeally via the blood treatment apparatus by carrying out an ultrafiltration process.

30. The control device or closed-loop control device according to claim 28, wherein the control device or closed-loop control device is configured for one or both of processing and evaluating one or both of an arterial blood pressure reading and a venous blood pressure reading.

31. The control device or closed-loop control device according to claim 30, wherein the control device or closed-loop control device is configured to trigger an alarm, to cause an interruption or a termination of an ultrafiltration, to cause another blood pressure measurement to be determined and to evaluate the other blood pressure measurement, to cause an on-line bolus to be administered, and/or to output corresponding information for attention of a user should an evaluation of the arterial blood pressure reading and/or of the venous blood pressure reading show that the patient's blood pressure has reached or is no longer within pre-determined ranges.

32. A medical set comprising: a blood pressure measuring device; and a control device or closed-loop control device configured to carry out mechanical steps of a method for determining or recommending at least one time point for measuring pressure measurements on a patient during a treatment session in which the patient's blood is treated extracorporeally via a blood treatment apparatus, the method comprising: monitoring, during the treatment session, one or more of an ultrafiltration rate with which the patient's blood is treated, a relative blood volume, and a sodium concentration for one or more changes in or for fulfilling one or more pre-determined criteria, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration; and transmitting a signal to a blood pressure measuring device when any of the one or more pre-determined criteria or any of the one or more changes are met, respectively, for one or more of the ultrafiltration rate, the relative blood volume, and the sodium concentration.

33. The medical set according to claim 32, wherein the patient's blood is treated extracorporeally via the blood treatment apparatus by carrying out an ultrafiltration process.

34. The medical set according to claim 32, further comprising the blood treatment apparatus.

35. The medical set according to claim 34, wherein the blood treatment apparatus comprises a hemodialysis apparatus, a hemofiltration apparatus, or a hemodiafiltration apparatus for acute or chronic renal replacement therapy.

36. The medical set according to claim 35, wherein the renal replacement therapy comprises continuous or intermittent procedures.

37. The medical set according to claim 32, further comprising sensors arranged and configured to extracorporeally measure the sodium concentration in dialysis liquid or in dialysate and/or measure the relative blood volume.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0082] The present disclosure is exemplarily explained with regard to the accompanying drawings in which same reference numerals refer to the same or similar components. In the figures the following applies:

[0083] FIG. 1 shows in a simplified, schematic representation a blood treatment apparatus according to the present disclosure with an extracorporeal blood circuit in a first embodiment or the representation of a flow diagram of a blood treatment apparatus according to the present disclosure, exemplarily embodied as a hemodiafiltration apparatus;

[0084] FIG. 2 shows examples of the implementation of the method according to the present disclosure with reference to a graphical representation of an exemplary treatment profile;

[0085] FIG. 3a shows a first alternative treatment profile of a blood treatment using ultrafiltration;

[0086] FIG. 3b shows a second alternative treatment profile of a blood treatment using ultrafiltration;

[0087] FIG. 4 shows an example for determining time points (t1, . . . ,t5) within a blood treatment using ultrafiltration in a graphical representation of a examplary treatment profile, which has been adapted based on the method according to the present disclosure; and

[0088] FIG. 5 shows examples of the implementation of the method according to the present disclosure with reference to a graphic representation of a further exemplary treatment profile.

DETAILED DESCRIPTION

[0089] FIG. 1 shows an extracorporeal blood circuit 300, which can be connected to the vascular system of the patient (not shown) for a treatment via double-needle access, or via single-needle access, using, for example, an additional Y-connector (reference numeral Y) as shown in FIG. 1. The blood circuit 300 can optionally be present in sections thereof in or on a blood cassette.

[0090] Pumps, actuators and/or valves in the area of the blood circuit 300 are connected to a blood treatment apparatus 100 according to the present disclosure or for example, to a control device 150 included within.

[0091] The blood circuit 300 includes (or is connected to) an arterial patient tubing clamp 302 and an arterial connection needle of an arterial section or of an arterial patient line, a blood withdrawal line or a first line 301. The blood circuit 300 further includes (or is connected to) a venous patient tubing clamp 306 and a venous connection needle of a venous section, a venous patient line, blood return line or second line 305.

[0092] A blood pump 101 is provided in or on the first line 301, a substituate pump 111 is connected to a dialysis liquid inlet line 104 for conveying fresh dialysis liquid, which is filtered through a further filter (F2) (substituate). A substituate line 105 can be in fluid communication with the inlet line 104. Using the substituate pump 101, substituate can be introduced by pre-dilution via a pre-dilution valve 107, or by post-dilution via a post-dilution valve 109, into line sections via corresponding lines 107a or 109a, for example into the arterial line section 301 or into the venous line section 305 (here between a blood chamber 303b of a blood filter 303 and a venous air separation chamber or venous blood chamber 29) of the blood circuit 300

[0093] The blood filter 303 includes the blood chamber 303b which is connected to the arterial line section 301 and the venous line section 305. A dialysis liquid chamber 303a of the blood filter 303 is connected to the dialysis liquid inlet line 104 leading to the dialysis liquid chamber 303a and a dialysate outlet line 102 leading away from the dialysis liquid chamber 303a which guides dialysate, i. e. used dialysis liquid. Dialysis liquid chamber 303a and blood chamber 303b are separated by a mostly semi-permeable membrane 303c. This membrane is what separates the blood side with the extracorporeal blood circuit 300 and the machine side with the dialysis liquid circuit or dialysate circuit, which is shown in FIG. 1 to the left of the membrane 303c.

[0094] The arrangement in FIG. 1 encompasses an optional detector 315 for detecting air and/or blood. The arrangement in FIG. 1 further encompasses one or two pressure sensors PS1 (upstream of the blood pump 101) and PS2 (downstream of the blood pump 101, which measures the pressure upstream of the blood filter 303 (“pre-hemofilter”)) at the positions shown in FIG. 1. Further pressure sensors may be provided, e.g., the pressure sensor PS3 downstream of the venous blood chamber 29.

[0095] An optional single-needle-chamber 317 is used in FIG. 1 as a buffer and/or a compensating reservoir in a single-needle procedure in which the patient is connected to the extracorporeal blood circuit 300 via only one of the two blood lines 301, 305.

[0096] The arrangement in FIG. 1 additionally includes an optional detector 319 for detecting air bubbles and/or blood.

[0097] An addition point 25 for Heparin may be optionally provided.

[0098] Shown on the left in FIG. 1 is a mixing device 63 which, from containers A (for A concentrate via the concentrate supply 67) and B (for B concentrate via the concentrate supply 69), provides a predetermined mixture for the respective solution for use by the blood treatment device 100 provides. The solution contains, in the heater 61 for example, warmed water from the water source 55 (on-line, e.g., as reverse osmosis water or from bags).

[0099] A pump 71, that may be referred to as a concentrate pump or sodium pump is in fluid communication with the mixing apparatus 63 and with a source having sodium, such as the container B, and/or conveys therefrom.

[0100] Furthermore, an outlet 53 for the effluent can be seen in FIG. 1. An optional heat exchanger 57 and a first flow pump 59, which is suitable for de-gassing, complete the arrangement shown.

[0101] A further pressure sensor for measuring the filtrate pressure or the membrane pressure of the blood filter 303 may be provided as PS4 downstream of the blood filter 303 on the water-side, however preferably upstream of the ultrafiltration pump 131 in the dialysate outlet line 102. Further optional pressure measuring points P may also be provided.

[0102] Blood, which leaves the blood filter 303, passes through an optional venous blood chamber 29, which can include a de-aeration device 31 and/or may be in fluid communication with a further pressure sensor PS3.

[0103] The exemplary arrangement shown in FIG. 1 includes a control device or closed-loop control device 150. This can be in wired or wireless signal communication with any of the components referred to herein—such as to the blood pump 101—in order to control or regulate the blood treatment apparatus 100. It is optionally configured in order to carry out the method described herein, e.g., automatically.

[0104] By using the device for on-line mixing of the dialysis liquid, a variation in the sodium content thereof controlled by the control device 150, is possible within certain limits. For this purpose, measurements determined via the conductivity sensors 163a, 163b may be taken into account. Should an adjustment of the sodium content of the dialysis liquid (sodium concentration) or of the substituate be required or desired, this can be done by adjusting the delivery rate of the sodium pump 71.

[0105] Furthermore, the blood treatment apparatus 100 includes means for conveying fresh dialysis liquid as well as dialysate. For this purpose, the first flow pump 59, which conveys fresh dialysis liquid towards the blood filter 303, is provided upstream of the blood filter 303. A first valve may be provided between the first flow pump 59 and the blood filter 303, which opens or closes the inlet to the blood filter 303 on the inlet side. A second optional flow pump 169 is provided, for example downstream of the blood filter 303, which conveys dialysate to the outlet 53. A second valve may be provided between the blood filter 303 and the second flow pump 169, which opens or closes the outlet on the outlet side.

[0106] Furthermore, the blood treatment apparatus 100 optionally includes a device 161 for balancing the flow going into and coming out of the dialyzer 303 on the machine side. The device 161 for balancing is preferably arranged in a line section between the first flow pump 59 and the second flow pump 169.

[0107] The blood treatment apparatus 100 further encompasses means, such as the ultrafiltration pump 131, for the precise removal of a fluid volume from the balanced circuit as specified by the user and/or by the control device 150.

[0108] Sensors such as the optional conductivity sensors 163a, 163b serve to determine the conductivity, which in some embodiments is temperature-compensated, as well as the liquid flow upstream and downstream of the dialyzer 303.

[0109] Temperature sensors 165a, 165b can be provided individually or in groups. Temperature readings supplied by them can be used according to the present disclosure to determine a temperature-compensated conductivity.

[0110] A leakage sensor 167 is optionally provided.

[0111] Further flow pumps, in addition or as an alternative to, the one indicated with the reference numeral 169 for example, can also be provided.

[0112] A row of optional valves is each indicated in FIG. 1 with a V. By pass valves are indicated with a VB.

[0113] In some embodiments the control device 150 determines the electrolyte and/or liquid balancing based on the measurement readings of the afore-mentioned, optional sensors.

[0114] Filters F1 and F2 may be provided in series-connection.

[0115] The filter F1 here serves exemplarily, via the mixing apparatus 63, to produce sufficiently pure dialysis liquid, even when using impure water, which then flows through the blood filter 303, e.g., according to the counter-current principle.

[0116] Exemplarily, here the filter F2 serves to generate a sterile or sufficiently filtered substituate from the sufficiently pure dialysis liquid, which leaves the first filter F1, by filtering out pyrogenic substances, for example. This substituate can safely be added to the patient's blood flowing extracorporeally and thus ultimately be supplied to the patient's body.

[0117] FIG. 1 shows that the control device 150 of the blood treatment apparatus 100 may be in wired or wireless signal communication with a blood pressure measuring device 700 and/or with a blood volume monitor 800 and is configured and prepared for this, for example, through corresponding mutual programming and coordination.

[0118] The optional blood treatment apparatus 100 of the set according to the present disclosure is shown in FIG. 1 as a device for hemo(dia)filtration. However, hemodialysis devices also fall within the scope of the present disclosure, even though they are not specifically shown in the figures.

[0119] The present disclosure is not limited to the embodiment described above, this serves only as an illustration.

[0120] The arrows shown in FIG. 1 generally indicate the direction of flow in FIG. 1.

[0121] FIG. 2 shows examples for time points t1, . . . ,t5, set according to the present disclosure, within the time sequence of an exemplary treatment profile, wherein the pre-determined ultrafiltration rate UF_rate of this treatment profile (e.g., in the unit ml/h) is shown over time t (e.g., in the unit h).

[0122] Such a treatment profile may be stored on the blood treatment apparatus and can be selected by the physician or qualified treatment personnel for the treatment of a specific patient.

[0123] The example given shows a treatment profile with alternating, clear changes between lower and higher ultrafiltration rates UF_rate. The sections of the treatment profile with the higher ultrafiltration rates can also be referred to as peaks, since they correspond to peaks of the ultrafiltration rate UF_rate over the course of the treatment profile over time.

[0124] The method according to the present disclosure can, with knowledge of and due to the stored treatment profile or its pre-determined course, determine ad hoc or in advance at which time points t1, . . . T5 measuring a patient's blood pressure measurement is considered useful according to the present disclosure. Since especially high ultrafiltration rates UF_rate are usually less tolerated by the (respective) patient, the end of such a peak is likely to determine the current condition of the patient, e.g., to allow his current blood pressure readings to be determined. These time points t1, . . . , t5 are marked with an “x” in the diagram in FIG. 2.

[0125] Alternatively or additionally, if the course of the treatment profile is known, the duration D of such a peak can be used to determine at least one time point t1, . . . , t5. For the sake of clarity, the duration D is only indicated with a reference numeral at one peak in FIG. 2.

[0126] A corresponding signal sent to the blood pressure measuring device 700 at such a time point t1, . . . t5 can lead—after the method—to the measurement of a blood pressure reading. After processing the measured blood pressure reading, for example in the control device or closed-loop control device 150 (see FIG. 1), this can lead to selecting an alternative treatment profile (see FIGS. 3a and 3b) or to changing the course of the selected treatment profile (see FIG. 4), with which treatment should preferably be continued in the further course of the blood treatment session.

[0127] The number of the set time points according to the present disclosure (here 5) is purely as an example and is not in any way to be understood as limiting.

[0128] FIG. 3a shows a first alternative treatment profile of a blood treatment using ultrafiltration.

[0129] A blood pressure reading, measured at a time point set using the method according to the present disclosure, may show that the ultrafiltration rate UF_rate of the selected treatment profile (e.g., the treatment profile with alternating changes shown in FIG. 2) is not sufficiently well tolerated by the patient being treated. A linear course of the ultrafiltration rate UF_rate should be exemplarily shown here, which could be used as a first alternative treatment profile if the above-mentioned criteria are met. As can easily be seen, the ultrafiltration rate UF_rate in this example of a treatment profile decreases linearly from the beginning to the end during the blood treatment session.

[0130] It can be assumed that a decreasing ultrafiltration rate UF_rate can be more easily tolerated by a patient who did not perform as well with the treatment profile of FIG. 2.

[0131] FIG. 3b shows a second alternative treatment profile of a blood treatment using ultrafiltration.

[0132] Similarly to FIG. 3a, it is again assumed in this example that the ultrafiltration rate UF_rate of the selected treatment profile (for example the treatment profile with alternating changes of FIG. 2) was not sufficiently well tolerated by the patient being treated. A step-shaped course of the ultrafiltration rate UF_rate should be mentioned here as an example of a second alternative treatment profile, which could be used if the above-mentioned criteria are met. As can easily be seen, in this example of a treatment profile during the blood treatment session the ultrafiltration rate UF_rate exemplarily decreases two times, each time by one level from the beginning to the end.

[0133] Here, too, it can be assumed that the decreasing ultrafiltration rate UF_rate can be more easily tolerated by the patient being treated. According to the present disclosure, at the time points marked “x” which can be determined by the method according to the present disclosure, a signal is again sent to the blood pressure measuring device 700, which can be followed by a determination of a further blood pressure reading and its evaluation and/or processing. According to the present disclosure, provision may be made so that the ultrafiltration rate UF_rate is reduced or maintained at these stages in accordance with the determined blood pressure readings.

[0134] In some embodiments, increasing the ultrafiltration rate UF_rate again or returning to a previously used treatment profile may be considered, based on the determining and evaluation or processing of blood pressure measurement readings.

[0135] FIG. 4 shows an example for determining time points t1, t5 during a blood treatment session using ultrafiltration in a graphical representation of an exemplary treatment profile, adapted according to the present disclosure.

[0136] As in FIG. 3a, in this example it is again assumed that the ultrafiltration rate UF_rate of the selected treatment profile (e.g., the treatment profile in FIG. 2 with alternating changes) was not sufficiently well tolerated by the patient being treated, this was detected at the first time point t1. In contrast to the treatment profile in FIG. 2, the treatment profile selected by the physician is amended accordingly so that the height of the peaks of the ultrafiltration rate UF_rate are adjusted, for example lowered, on the basis of the blood pressure reading which was determined at time point t1, that was determined according to the present disclosure. The different heights of the peaks of the ultrafiltration rate UF_rate before and after the adjustment of the ultrafiltration rate UF_rate are illustrated in FIG. 4 by two horizontal dotted lines.

[0137] In such embodiments, it is possible to again adjust the ultrafiltration rate UF_rate upwards if it is well tolerated by the patient, i.e. in connection with later measured, once again acceptable blood pressure readings. This is indicated in FIG. 4 in the course of the treatment profile over time following the time points t3 and t4 which are marked with “x”.

[0138] FIG. 5 shows that the statements made here in the description of the figures regarding the criteria of the ultrafiltration rate UF_rate also apply without restriction to the criteria of the relative blood volume RBV or the criteria of the sodium concentration [Nat] within a blood treatment session.

LIST OF REFERENCE NUMERALS

[0139] 25 addition point for Heparin (optional) [0140] 29 venous blood chamber (optional) [0141] 31 de-aeration device [0142] 53 outlet [0143] 55 water source [0144] 57 heat exchanger [0145] 59 first flow pump [0146] 61 heat apparatus [0147] 63 mixing apparatus [0148] 67 concentrate supply [0149] 69 concentrate supply [0150] 71 concentrate pump; sodium pump [0151] 100 blood treatment apparatus [0152] 101 blood pump [0153] 102 dialysate outlet line, effluent inlet line [0154] 104 dialysis liquid inlet line [0155] 105 substituate line [0156] 107 pre-dilution valve [0157] 107a line [0158] 109 post-dilution valve [0159] 109a line [0160] 111 pump for substituate [0161] 121 pump for dialysis liquid [0162] 131 pump for dialysate or effluent [0163] 150 control device or closed-loop control device [0164] 161 device [0165] 163a conductivity sensor [0166] 163b conductivity sensor [0167] 165a temperature sensor [0168] 165b temperature sensor [0169] 167 leakage sensor [0170] 169 second flow pump [0171] 300 extracorporeal blood circuit [0172] 301 first line (arterial line section) [0173] 302 first tubing clamp [0174] 303 blood filter or dialyzer [0175] 303a dialysis liquid chamber [0176] 303b blood chamber [0177] 303c semi-permeable membrane [0178] 305 second line (venous line section) [0179] 306 (second) tubing clamp [0180] 315 detector [0181] 317 single-needle-chamber [0182] 319 detector [0183] 700 blood pressure measuring device [0184] 800 blood volume monitor [0185] F1 filter [0186] F2 filter [0187] A container [0188] B container [0189] D pre-determined duration [0190] [Na.sup.+] sodium concentration [0191] P pressure measuring points [0192] PS1 arterial pressure sensor (optional) [0193] PS2 arterial pressure sensor (optional) [0194] PS3 pressure sensor (optional) [0195] PS4 pressure sensor for measuring the filtrate pressure (optional) [0196] RBV relative blood volume [0197] t1 time point [0198] UF_rate ultrafiltration rate [0199] V valves [0200] VB bypass valves [0201] Y Y-connector