EP4213908A1

EP4213908A1 - Method for identifying the type of a medical filter, and devices

Info

Publication number: EP4213908A1
Application number: EP21778374.5A
Authority: EP
Inventors: Nicolas Clemens Lippert
Original assignee: Fresenius Medical Care Deutschland GmbH
Current assignee: Fresenius Medical Care Deutschland GmbH
Priority date: 2020-09-18
Filing date: 2021-09-15
Publication date: 2023-07-26
Also published as: US20230330314A1; WO2022058329A1; DE102020124395A1; CN116209486A

Abstract

The present invention relates to a method for identifying a type of medical filter, a class of filters or a feature of a medical filter, wherein the filter has at least a first filter compartment and a second filter compartment, which are separated from each other by a filter medium. The method here comprises the step of generating a pressure in a fluid on a first side of the filter medium of a filter by means of a first pressure source, as a result of which the filter is subjected to pressure. The method further comprises the step of measuring over time the pressure curve on the first side of the filter medium, as first pressure curve (1000), by means of a first pressure sensor (59) arranged between the first pressure source and the filter, and also the pressure curve on the second side of the filter medium, as second pressure curve (2000), by means of a second pressure sensor (73). The method further comprises the step of evaluating both the first pressure curve (1000) and the second pressure curve (2000) so as to obtain an evaluation result (3000, 4000), and the step of assigning the medical filter, subjected to the pressure, to a type of filter or a class of filters or of identifying a feature of the medical filter.

Description

description

Procedure for identifying the type of a medical

Filters , and fixtures

The present invention relates to a method according to claim 1, a control device according to claim 11, a medical device according to claim 12, also a digital storage medium according to claim 15, a computer program product according to claim 16 and a computer program according to claim 17 or according to the preambles or generic terms of these claims.

Filters with semi-permeable membranes are used in extracorporeal blood treatment, for example in hemofiltration, hemodialysis, hemodiafiltration, plasmapheresis and other treatment options.

Different filter types are often used in the blood treatments of the same treatment options, even if the same blood treatment device is always used. Since the success of the treatment essentially depends on using a filter of the type suitable for the treatment, it is essential to ensure before starting the treatment that a filter of the correct type is being used for the upcoming treatment. It is usual for the operator of a treatment device to equip it with a (usually disposable) filter before the start of the treatment session, which he uses himself, e.g. B. taken from a magazine or warehouse, provides. Due to operator error in practice, however, he can give a wrong or an unsuitable filter can be used .

In the case of methods known from the prior art, an error in the selection of the filter by the operator is ruled out in that the treatment device in which the filter is inserted or with which the filter is used together selects the type of filter based on information available externally on the filter Characteristics such as mechanical or optical characteristics are determined and, in the event of a filter that is not suitable for the treatment option at hand, measures are taken (alarm, blocking of treatment options, etc.), whereby treatment with an unsuitable filter can be prevented. The detection of these external features of a filter requires the use of at least one sensor or other component that is provided specifically for this type of filter identification.

An object of the present invention is to propose another method for identifying the type of medical filter, a class of filters or a characteristic of a medical filter. In addition, suitable devices should be specified.

The object according to the invention is solved by the method with the features of claim 1 . It is also achieved by means of the control device having the features of claim 11, the medical device having the features of claim 12, the digital storage medium having the features of claim 15, the computer program product having the features of claim 16 and the computer program having the Features of claim 17 . Thus, a method for identifying a type of medical filter, a class of filters, or a characteristic of a medical filter is proposed. In this case, the filter has at least a first filter compartment and a second filter compartment, which are separated from one another by a filter medium.

The method according to the invention comprises the step of generating or raising a pressure in the fluid (fluid pressure), in particular a liquid, on a first side of the filter medium of a provided filter. This takes place by means of a first pressure source, for example a pump, as a result of which pressure is built up in the filter.

The method also includes measuring the pressure curve over time, both on a first side of the filter medium, with a first pressure curve being obtained, and on a second side of the filter medium, with a second pressure curve being obtained. The measurement takes place in particular during the build-up of pressure and/or when the pressure has built up. The first pressure profile is measured by means of a first sensor, which is arranged between the first pressure source and the filter. The second pressure profile is measured by means of a second sensor.

As a further step, the method includes an evaluation of both the first pressure curve and the second pressure curve. This evaluation results in obtaining at least one evaluation result.

Furthermore, the method further comprises the step of associating the medical filter 10 that has been subjected to the pressure as described above with a type of filter 10 Class of filters or, alternatively or additionally, the step of identifying a feature of the medical filter. The assignment is based on the at least one evaluation result.

For the purpose of assignment, the evaluation result can be compared with suitable reference values and/or measured therefrom.

Such reference values can be stored in a memory device suitable for this purpose, e.g. B. in a data memory, which in turn is part of a treatment device. The storage device may be or include any embodiment set forth herein for a storage device.

Furthermore, the present invention relates to a control device that is configured to interact with a provided medical device that has a filter, a first pressure source, a first pressure sensor and a second pressure sensor—in particular as disclosed herein—the method according to the invention to cause or carry out.

Interaction can be or include actuation, control or regulation. Interaction may be or require a signal connection.

Furthermore, the present invention relates to a medical device.

This has a filter, a first pressure source, a first pressure sensor and a second pressure sensor. she also has a control device according to the invention.

Alternatively, it is connected to each of the aforementioned devices.

A digital, in particular non-volatile, storage medium according to the invention, in particular in the form of a machine-readable carrier, in particular in the form of a diskette, memory card, CD, DVD, EPROM, FRAM (ferroelectric RAM) or SSD (solid-state drive), in particular with electronic or optical readable control signals can be configured to configure a conventional control device to a control device according to the invention, with which the steps, in particular the machine steps, of the method according to the invention can be initiated.

All, some or some of the steps, in particular the steps that can be carried out by machine, of this method can be initiated.

A computer program product according to the invention has a program code or a signal wave that is volatile, transient or stored on a machine-readable medium, by means of which a conventional control device is configured into a control device according to the invention, with which the steps, in particular the machine steps, of the method according to the invention are initiated can be when the computer program product runs on a computer.

All, some or some of the steps, in particular the steps that can be carried out by machine, of this method can be initiated. According to the invention, a computer program product can be, for example, a computer program stored on a carrier, an embedded system as a comprehensive system with a computer program (e.g. electronic device with a computer program), a network of computer-implemented computer programs (e.g. client/server system, cloud computing system, etc.) or a computer on which a computer program is loaded, running, stored, executed or developed.

The term "machine-readable carrier" as used herein, in certain embodiments of the present invention, denotes a carrier that contains data or information that can be interpreted by software and/or hardware. The carrier can be a data carrier, such as a diskette, a CD, DVD, a USB stick, a flash card, an SD card and the like, as well as any other memory or any other storage medium mentioned herein.

A computer program according to the invention comprises a program code, by means of which a conventional control device is configured into a control device according to the invention, with which the steps, in particular the machine steps, of the method according to the invention can be initiated when the computer program runs on a computer.

All, some or some of the steps, in particular the steps that can be carried out by machine, of this method can be initiated. According to the invention, a computer program can be understood, for example, as a physical, marketable software product which has a program.

In all of the above and following statements, the use of the expression "may be" or "may have" etc . synonymous with "is preferably" or "has preferably" etc. to understand and is intended to explain an embodiment of the invention.

Whenever numerical words are mentioned herein, the person skilled in the art understands them as indicating a numerical lower limit. Provided that this does not lead to a discernible contradiction for the person skilled in the art, the person skilled in the art always reads "at least one" or "at least one" when specifying "a" or "an". This understanding is also included in the present invention, as is the interpretation that a numerical word such as "a" can alternatively be meant as "exactly one", wherever this is technically possible for a person skilled in the art. Both are covered by the present invention and apply to all numerals used herein.

When “programmed” or “configured” is mentioned here, it is also disclosed that these terms are interchangeable.

Advantageous further developments of the present invention are each the subject of dependent claims and

Execution forms . If an embodiment is mentioned herein, it represents an exemplary embodiment according to the invention.

If it is disclosed herein that the object according to the invention has one or more features in a specific embodiment, it is also disclosed here in each case that the object according to the invention expressly does not have this or these features in other embodiments that are also according to the invention has e.g. B. as a disclaimer. For each embodiment mentioned herein, it is therefore the case that the opposite embodiment, for example formulated as a negation, is also disclosed.

Embodiments according to the invention can have one or more of the features mentioned above and/or below in any technically possible combination.

In some embodiments, the filter selected by the operator and thus available for use is of a specific type or type. assigned to a class of filters, and the filter type thus determined for use is compared with a filter type required or recommended by the factory or generally for the specific medical device or for the treatment option specifically planned with the device. In these embodiments, provision can also be made to automatically block the implementation of the specifically planned treatment option preselected on the medical device by means of the medical device if the comparison reveals that the filter is unsuitable for the preselected treatment option, a non-approved filter type or result in the like . If, for example, it is recognized that a plasma filter was inadvertently connected instead of a dialyzer, dialysis treatment can be blocked, or vice versa.

In some embodiments, the pressure profile is measured in a flow of dialysis liquid or dialysate which flows through the filter, or in a dialysis liquid or dialysate with which the filter is fluidly connected.

In some embodiments, the method also includes the outputting of an evaluation result, a consequence thereof or a corresponding signal based thereon. The output can be signal-bound, it can e.g. B. visual, acoustic, etc. respectively .

In some embodiments of the method according to the invention, the filter is a dialyzer or blood filter.

In some embodiments, the first pressure source is or includes a blood pump.

In some embodiments, the first filter compartment is a blood chamber and/or the second filter compartment is a dialysis fluid compartment.

In some embodiments, the filter medium is a semipermeable membrane or comprises a large number of such membranes.

In some embodiments, the second pressure sensor is between a dialysis fluid pump and a Dialysate pump of the medical device arranged. The dialysate pump can also be referred to as a filtrate pump or effluent pump.

In some embodiments, the pressure in the fluid is increased by means of the first pressure source until a predetermined pressure is reached. In this case, the first pressure source is preferably switched off after this pressure has been reached, no longer delivers, or the pressure is not increased further in any other way (eg closing a valve or opening a bypass).

In some embodiments, the first pressure source conveys the fluid at a flow rate of at least 150 ml/min, preferably at least 180 ml/min, particularly preferably at least 200 ml/min, or is controlled accordingly.

In some embodiments, the first pressure source conveys the fluid for at least 5 seconds, preferably at least 8 seconds, particularly preferably at least 10 seconds, or is controlled accordingly.

In some embodiments, the pressure profile is measured both by means of the first pressure sensor and by means of the second pressure sensor, while the first pressure source conveys the fluid or is controlled accordingly.

In some embodiments, the evaluation to achieve the evaluation result includes or consists of smoothing, in particular by means of a median filter, of the pressure curve measured by means of the first pressure sensor and/or the pressure curve measured by means of the second pressure sensor. In some embodiments, the evaluation to achieve the evaluation result is or consists of the formation of a differential pressure profile between the pressure profile measured by means of the first pressure sensor and the pressure profile measured by means of the second pressure sensor.

In some embodiments, the evaluation to obtain the evaluation result is or consists of integrating the differential pressure curve over time.

In some embodiments, the integration of the differential pressure profile is or consists of a numerical integration, preferably by applying the trapezoidal rule.

In some embodiments of the medical device according to the invention, the control device is further configured to use an alarm device, which can be part of the medical device, to issue an alarm in order to prevent a treatment option using the medical device and/or to To stop the pump of the medical device, preferably a pump which promotes medical liquid, in particular dialysis liquid. According to the configuration, this occurs when the control device determines or establishes that the evaluation result and/or the result of the assignment does not meet a predetermined criterion.

In some embodiments, the criterion can be based on the treatment option set for the medical device orientate or take these into account, or the type of filter required for the treatment option.

In some embodiments of the medical device according to the invention, the control device is signal-connected to an output device for outputting an indication to the operator that the filter used is not of the required type, that treatment options are blocked, etc.

In some embodiments, the medical device is configured as a blood treatment device, blood purification device or dialysis device, as a filtration device, as a diafiltration device or as a dialysis device in any other configuration known to those skilled in the art for blood purification, such as for hemodialysis, hemofiltration or hemodiafiltration. It may be a plasmapheresis device.

The medical device is in certain

Embodiments configured for use in continuous venous hemodiafiltration (CW-HDF) and/or for use in acute dialysis or as a critical care device

In some embodiments, the method is carried out and completed using the medical device before the start of a treatment or examination of a patient. It is preferably carried out and completed after completion of the filling or the priming of an extracorporeal blood circuit connected to the medical device for an upcoming treatment or examination of the patient. In some embodiments of the medical device according to the invention, the control device is configured to issue an alarm by means of an alarm device if the evaluation result determines that the inserted filter is of a different type than intended or required.

Alternatively or additionally, the control device can be configured to suppress a treatment option using the medical device and/or to stop a pump of the medical device in such a case. This pump is preferably a pump which conveys liquid, in particular dialysis liquid or blood, through the filter.

In certain embodiments, the medical device according to the invention is connected to an extracorporeal blood circuit and/or a hose system.

In some embodiments, a pressure profile is a sequence of at least 3, 5, 30, 50 or more measurements, or a sequence of measurements at 3, 5, 30, 50 or more points in time. The points in time can be within a maximum time period of 3, 5, 10, 15, 20 or more seconds.

In some embodiments, the method and in particular the evaluation does not include determining and/or communicating an ultrafiltration constant.

In some embodiments, the measurement of the pressure profile on both the first side of the filter medium and on the second side of the filter medium does not represent the measurement of a transmembrane pressure. In some embodiments, the evaluation of both the first pressure profile and the second pressure profile while obtaining at least one evaluation result does not result in the level of the transmembrane pressure being output or communicated.

In some embodiments, the method does not include measuring and/or reporting the transmembrane pressure and/or a flow resistance of the filter.

In some embodiments, only the second pressure curve is measured on the hydraulic side of the medical treatment device. The first pressure curve is measured on the blood side or on the side of the blood tubing set.

In some embodiments, the pressure of the first pressure curve and/or the second pressure curve is used for the evaluation during an increase in the respective pressure (possibly after smoothing), not during a decrease (possibly after smoothing) of the pressure or pressure curve. For example, if the curve of pressure over time initially rises (increase in pressure along a rising section of the curve), only to decrease again after a maximum pressure has been reached (drop in pressure along a descending section of the curve), then the pressure in the rising section considered , not in the descending section .

Some or all of the embodiments according to the invention can have one, several or all of the advantages mentioned above and/or below. The present invention is easy to implement in existing systems since the filling and rinsing is carried out as standard before a treatment session and according to the invention therefore on devices such as blood pumps, dialysate pumps, pressure sensors, hose clamps, etc. that are already regularly present on a treatment device. can be used .

By means of the method according to the invention, an automatic check of the filter type can take place before the start of the treatment, which as a result can output the statement as to whether the connected filter is suitable for the pending treatment or not. Since provision can be made for automatically blocking the preselected treatment option in the event of a lack of suitability, patient safety can be significantly increased.

By means of the present invention, a very reliable differentiation of filters/dialyzers may be possible, even of filters or dialyzers whose distinguishable features are intrinsically very close or very similar to one another. This advantageously contributes to increasing patient safety.

The implementation of the teaching according to the invention does not require any mechanical solution in the sense of moving parts, which can make it robust, easy to design and low-maintenance. A considerable advantage according to the invention consists in the protection of the patient mentioned herein even before the medical device is used for his treatment or examination. The present invention is explained below by way of example with reference to the attached drawing, in which identical reference symbols denote the same or similar components. In the figures of the drawing applies:

Fig. 1 shows a greatly simplified representation of a process flow diagram of a medical device according to the invention, here a blood treatment device;

Fig. FIG. 2 shows a section of the medical device according to the invention from FIG. 1 with the devices necessary for carrying out the method according to the invention;

Fig. 3a shows a first example for the recording of pressure curves and their evaluation; and

Fig. 3b shows a second example for the recording of pressure curves and their evaluation.

Fig. 1 shows, in a highly simplified representation, a method flow diagram of an exemplary medical device 500 according to the invention, here a blood treatment device.

The medical device 500 is optionally connected to an extracorporeal blood circuit 600 and further optionally to an effluent bag 75 . The extracorporeal blood circuit 600 has a first line 49 , here in the form of an arterial line section.

The first line 49 is optionally in fluid connection with a blood treatment device, here a blood filter or dialyzer 57 as an example. The blood filter 57 has a dialysis fluid chamber 57b and a blood chamber 57a, which are separated from one another by a mostly semi-permeable membrane 57c.

The extracorporeal blood circuit 600 also has at least one second line 69 , here in the form of a venous line section. Both the first line 49 and the second line 69 can serve to connect them to the vascular system of the patient (not shown).

The first line 49 is optionally connected to a (first) hose clamp 51 for blocking or closing the line 49 . The second line 69 is optionally connected to a (second) hose clamp 67 for blocking or closing the line 69 .

The ones shown in Fig. 1 by only some of its features and schematically represented medical device 500 has a blood pump 55 '. The blood pump 55' pumps blood through portions of the extracorporeal blood circuit 600 and toward the blood filter or dialyzer 57, as indicated by the small arrowheads, during treatment of the patient. In the run-up to a treatment session, the blood pump 55' is used to fill and flush parts of the medical device 500 and sections of the extracorporeal blood circuit 600 with liquid. Fresh dialysis fluid, e.g. B. from a source 71 along the dialysis fluid supply line into the dialysis fluid chamber of the blood filter 57 . The dialysis fluid tubing set is referenced 800 . The dialysis fluid leaves the dialysis fluid chamber as dialysate, if necessary. enriched by filtrate, via the dialysate drain line towards the optional ef fluent bag 75 or to a sink and is referred to herein as ef fluent.

The ef fluent from the optional ef fluent bag 75 can be discarded into a sink using an ef fluent drain line. In some embodiments, the effluent is discarded directly into a drain using the dialysate discharge line (not shown here).

The source 71 can be a bag or a container, for example. The source 71 may also be a fluid line from which on-line and/or continuously generated or mixed liquid is provided, e.g. B. a hydraulic outlet or port of the medical device 500 .

The dialysis liquid supply line of FIG. 1 optionally has a heating bag 1 or is connected to one. The heating bag 1 is placed in a first heating device 100 in order to supply heated dialysis fluid to the blood filter 57 . This serves to counteract cooling of the patient to be treated. A further source 71' with a substituate can optionally be provided. It may correspond to source 71 or be a source of its own.

A substituate line leading from the source 71' to the extracorporeal blood circuit 600 can also have a second heating bag 1' or be connected to one. The substituate tubing set z bears the reference number 700. The second heating bag 1' can be placed in a second heating device 100' in order to supply heated substituate to the extracorporeal blood circuit 600. This also serves to counteract cooling of the patient to be treated.

In addition to the aforementioned blood pump 55' and the pump 55 for dialysis liquid, the arrangement shown in FIG. also referred to as a filtrate pump or dialysate pump).

An optional arterial sensor 53 is provided upstream of the blood pump 55'. During treatment of the patient, it measures the pressure in the arterial line.

A further pressure sensor 59 is optionally provided downstream of the blood pump 55', but upstream of the blood filter 57 and, if provided, preferably upstream of an addition point 61 for an anticoagulant, for example heparin. It measures the pressure upstream of the blood filter 57 ("pre-hemof liter"). Yet another pressure sensor 73 can be provided downstream of the blood filter 57 , but preferably upstream of the pump 55 ''' , in the dialysate discharge line for measuring the filtrate pressure of the blood filter 57 .

A control or regulating device 550 according to the invention, which is only indicated, is configured to run or cause the medical device 500 . It can optionally also be configured to otherwise control or regulate the medical device 500, for example for the treatment of the patient. It can be connected to each of the components mentioned here - in any case or in particular to the blood pump 55' and the pressure sensors 59 and 73 - in a wired or wireless signal connection for controlling or regulating the blood treatment device 100 and in particular the pressure in the arterial line 49 and in the blood filter 57 serve .

Blood leaving the blood filter 57 flows through an optional venous blood chamber 63 which can have a ventilation device and be in fluid connection with a further pressure sensor 65 for measuring the venous pressure.

Fig. FIG. 2 shows a section of the medical device 500 according to the invention from FIG. 1 with the devices necessary for carrying out the method according to the invention.

A prerequisite for carrying out the method according to the invention is a preceding step of filling the tubing set 600 , 800 and the dialysate discharge line 77 , which is not part of the method according to the invention. An example follows for the generation of a pressure profile with simultaneous measurement of the pressures or pressure profile within the scope of the method according to the invention.

For this purpose, some or all of the aforementioned pumps, in particular the blood pump 55', the dialysis liquid pump 55 and the dialysate pump 55''', are first stopped in the aforementioned hose sections. The pumps that are stopped or not pumping sufficiently close the corresponding hose lines in most embodiments, since they are regularly designed as occluding pumps.

The venous tube clamp 67 is preferably closed and the arterial tube clamp 51 is opened. After a short waiting time, for example one second, the blood pump 55', initiated by the control device 550, starts to run at a predetermined flow rate, preferably about 200 ml/min, and runs for a predetermined period of time, for example ten seconds. This comparatively high flow through the blood pump 55' serves to generate an easily measurable pressure curve 1000 or 2000 (see FIGS. 3a and 3b). The blood pump 55' is then stopped.

During the pumping activity, the pressure values are recorded at the two pressure sensors 59 (pre-filter) and 73 (filtrate) and thus on each side of the filter medium, here the semi-permeable membrane 57c, and preferably in a storage device (not shown in Fig. 2). saved. The determined pressure values serve as raw data for the evaluation in connection with FIGS. 3a and 3b is described in more detail. The detection preferably takes place in the unit [mmHg].

Furthermore, it can be ensured that the hose system of the medical treatment device 500 is largely depressurized again after the pressures have been measured as described herein.

For this purpose, after another short waiting time, for example five seconds or more, the venous hose clamp 67 can be opened and the dialysate pump 55'' can be operated at a predetermined flow rate, for example approx. 200 ml/min for a certain period of time, for example ten seconds to start running.

After a further waiting time, preferably ten seconds, the two hose clamps 51 and 67 can finally be closed again.

3a shows a first example for the measurement of first and second pressure curves on a filter of a first filter type, here a plasma filter as an example. The two pressure curves are shown in the diagram, possibly pre-processed, as pressure curves 1000 or 2000 over time t (in the unit [ms]), their evaluations as curves 3000 or 4000.

The evaluation takes place after measuring the pressures e.g. B. by means of the components shown in Fig. 2 in the context of the method according to the invention as described above. The measured pressures are shown in FIG. 3a over time as pressure curves 1000, 2000. In this example, the determined pressure curves were advantageously smoothed using a mathematical filter, here for example using a median filter, preferably of order 11. This can be used, for example, to eliminate the deflections that are generated by the blood pump in the determined values. The above smoothing method is purely exemplary and is not limited to an 11th order median filter.

An absolute maximum as well as its position or temporal occurrence within the measured pressure values can optionally be determined from the smoothed values, or also in another way. The maximum defines the end of the pressure increase and thus the switch-off point in time of the blood pump 55' or the point in time at which the pressure was not increased any further for other reasons. The pressure curves up to this maximum, i. H. the pressure increase, relevant. An integration of the pressure values lying after this maximum or their differences is preferably omitted.

A difference curve 3000 can be calculated from the pressure curve 1000 (pre-filter) and the pressure curve 2000 (filtrate), in particular up to the point in time of the maximum, in that for each common measurement point in time the difference between the two corresponding measured pressure values, which are measured by means of the pressure sensors 59 or 73 were measured. If this difference 3000 is integrated numerically, for example using the trapezoidal method, the result is an integration curve of 4000.

In the example shown, this integration curve 4000 shows a positive slope. The profile of the integration curve 4000 can be used to assign the filter under consideration to a filter class or a filter type, since the procedure of pressure evaluation described here leads to different integration curves for different filter classes, according to the inventor's knowledge.

Fig. 3b shows a second example for the recording of pressure curves using a second filter type, here an example of a blood filter or dialyzer for continuous renal replacement therapy (CRRT).

Everything above to Fig. 3a also applies analogously to FIGS. 3b . However, in this example the integration curve 4000 shows a negative slope.

With the help of the result of the integration, a statement about the filter or filter type used can be made by comparing the result of the integration with reference integration results of known filter types. In general, a distinction between plasma and CRRT filters is already possible via the sign of the result. A positive sign indicates a plasma filter, otherwise a CRRT filter. About the amount of earnings may in some

In some embodiments, a more detailed statement about the filter can also be made, for example the specific model of the filter can be named. Reference List

1 , 1 ’ heating bag

49 first line; arterial line segment

51 hose clamp , arterial

53 pressure sensor for arterial pressure

55 dialysis fluid pump

55 ’ blood pump

55 ’ ’ Substituate pump

55 ’ ’ ’ dialysate pump ; filtrate pump ; Ef luent pump

57 blood filter ; dialyzer

57a blood chamber

57b Dialysis fluid s combs

57c semipermeable membrane

59 pressure sensor for hemofiltration pressure

61 Anticoagulant addition site

63 venous drip chamber

65 pressure sensor for venous pressure

67 hose clamp, venous

69 second line; venous line section

71 fluid source ( dialysis fluid )

71 ' Fluid Source ( Substituate )

73 Pressure sensor for filtrate pressure

75 eff luent bags

77 Dialysate drain line 100 first heater

100 ’ second heater

500 medical device

550 control or regulating device

600 extracorporeal blood circuit

700 Substituate tubing set e.g

800 dialysis fluid tubing set

1000 first pressure history (pre-filter)

2000 second pressure curve (filtrate)

3000 difference between the first and second pressure profile; difference curve

4000 numerical integration over the difference between the first and second pressure profiles;

integration curve

Claims

Expectations

1. A method for identifying a type of medical filter, a class of filters or a characteristic of a medical filter, the filter having at least a first filter compartment and a second filter compartment which are separated from one another by a filter medium, the method comprising the steps of:

generating a pressure in a fluid, in particular in a liquid, on a first side of the filter medium of a filter by means of a first pressure source, whereby the filter is subjected to pressure;

Measuring the pressure curve both on the first side of the filter medium using a first pressure sensor (59) arranged between the first pressure source and the filter as the first pressure curve (1000) and on the second side of the filter medium using a second pressure sensor (73) as the second pressure curve ( 2000) over time;

evaluating both the first pressure profile (1000) and the second pressure profile (2000) while obtaining at least one evaluation result (3000, 4000); and

Associating the pressurized medical filter with a type of filter, a class of filters, or identifying a characteristic of the medical filter based on the evaluation result (3000, 4000) . The method of claim 1, wherein the filter is a dialyzer or blood filter (57); and/or wherein the first pressure source is or comprises a blood pump (55'), and/or the first filter compartment is a blood chamber and the second filter compartment is preferably a dialysis fluid chamber, and/or wherein the filter medium is a semipermeable membrane. Method according to one of the preceding claims, wherein the second pressure sensor (73) is arranged between a dialysis fluid pump (55) and a dialysate pump (55''') of a medical device (500). Method according to one of the preceding claims, in which the first pressure source increases the pressure in the fluid until a predetermined pressure is reached, the first pressure source preferably being switched off or no longer delivering after it has been reached. Method according to one of the preceding claims, wherein the first pressure source the fluid with a flow of at least 150 ml / min, preferably at least 180 ml/min, particularly preferably at least 200 ml/min, promotes or is controlled accordingly. Method according to one of the preceding claims, wherein the first pressure source conveys the fluid for at least 5 seconds, preferably at least 8 seconds, particularly preferably at least 10 seconds, or is controlled accordingly. Method according to one of the preceding claims, wherein the pressure profile is measured both by means of the first pressure sensor (59) and by means of the second pressure sensor (73) while the first pressure source is conveying the fluid or is being controlled accordingly. Method according to one of the preceding claims, wherein the evaluation to achieve the evaluation result comprises or consists of smoothing, in particular by means of a median filter, of the pressure profile measured by means of the first pressure sensor (59) and/or of the pressure profile measured by means of the second pressure sensor (73). Method according to one of the preceding claims, wherein the evaluation to achieve the evaluation result is or consists of forming a differential pressure profile (3000) between the pressure profile measured by means of the first pressure sensor (59) and the pressure profile measured by means of the second pressure sensor (73). Method according to Claim 9, in which the evaluation to achieve the evaluation result is or consists of integrating (4000) the differential pressure profile (3000) over time. Control device (550) configured to, in cooperation with a provided medical device (500), which has a filter, a first pressure source, a first pressure sensor (59) and a second pressure sensor (73), the method according to any one of the preceding claims cause or carry out. Medical device (500), comprising

- A filter, a first pressure source, a first pressure sensor (59) and a second pressure sensor (73); and

- a control device (550) according to claim 11, or respectively connected thereto. The medical device (500) of claim 12, wherein the controller (550) is further configured to issue an alarm via an alarm device, to disable a treatment option via the medical device (500), and/or to stop a pump (55) of the medical device (500), preferably a pump which delivers medical liquid, in particular dialysis liquid, if the control device (550) determines that the evaluation result and/or the result of the assignment does not meet a predetermined criterion. Medical device (500) according to one of Claims 12 to 13, configured as a blood treatment device, blood purification device or dialysis device, for hemodialysis, hemofiltration or hemodiafiltration, or as a plasmapheresis device. Digital storage medium, in particular in the form of a floppy disk, CD or DVD or EPROM, with electronically readable control signals, configured to configure a control device to a control device (550) according to claim 11, by means of which the steps of the method according to one of claims 1 to 10 can be initiated. Computer program product with a program code stored on a machine-readable carrier in order to configure a control device into a control device (550) according to claim 11, by means of which the steps of the method according to one of claims 1 to 10 can be initiated. Computer program with a program code to configure a control device to a control device (550) according to claim 11, by means of which the steps of the method according to one of claims 1 to 10 can be initiated.