Dialysis machine with a device for identifying a dialyzer and method for identifying a dialyzer

Description

[0001] The present invention relates to a dialysis machine with a dialyzer, wherein the dialysis machine has a device for identifying the dialyzer, wherein the device has means for filling the dialyzer with liquid as well as means for determining the amount of liquid that is filled into the dialyzer, and wherein the device further has means for determining the pressure that is representative of the pressure in the area of ​​the dialyzer filled with liquid.

[0002] Dialysis machines known from the prior art have a dialyzer comprising a dialysate side and a blood side, separated by one or more semipermeable membranes. During treatment, waste products from the blood pass through this membrane into the dialysate, thus purifying the blood.

[0003] EP 2 919 829 B1 discloses such a dialysis machine.

[0004] For a patient's treatment, a doctor prescribes a specific dialyzer or dialyzer type, which is then configured in the dialysis machine's setup. Before treatment, a nurse's assistant sets up the dialysis machine, inserts the dialyzer, connects it to the dialysate circuit, and another nurse or the doctor performs the dialysis treatment. If the setup is incorrectly configured, or if the wrong dialyzer is used despite the correct setup, the patient may be at risk because they are not being treated with the intended dialyzer type. Furthermore, the dialyzer may malfunction, potentially leading to contamination of the dialysis machine and possibly blood loss for the patient.

[0005] The present invention is therefore based on the objective of providing a dialysis machine and a method that ensures that the correct dialyzer is used and employed for the treatment of the patient.

[0006] This problem is solved by a dialysis machine having the features of claims 1 and 7 and by a method having the features of claims 10 and 13.

[0007] According to claim 1, an evaluation device is provided which is configured to relate the measured fill quantity to the measured pressure and to compare it with a predetermined characteristic curve or with a predetermined characteristic value, wherein the evaluation device is further configured to output a signal which depends on whether the determined relationship (fill quantity / pressure or pressure / fill quantity) corresponds to the predetermined characteristic curve or with the predetermined characteristic value.

[0008] In this case, the size or type of dialyzer is determined during the filling of the dialyzer by the amount of dialysate (or other liquid) used and a pressure measurement.

[0009] The filling volume and the required pressure, according to the characteristic curve for the pore size, lead to a unique identification of the dialyzer. Based on the measurements, the dialyzer can be identified with a tolerance of ± 2 ml.

[0010] Preferably, a ratio of fill volume to pressure is calculated and compared with a characteristic curve or value that is typical for the desired dialyzer type. The measured fill volume / pressure ratio is then compared, for example, with a database entry regarding the properties of the dialyzer configured in the setup, thus verifying its plausibility. If the database entry does not match the measured ratio, a message or other signal may appear, prompting the user to check the settings or the dialyzer being used.

[0011] If no value is measured, the message may appear that the dialyzer could not be filled.

[0012] The present invention is of course also feasible if the ratio of pressure / filling volume is measured and this ratio is compared with a characteristic curve or with a characteristic value that is characteristic for the desired dialyzer type.

[0013] The term "pressure" used in the context of this invention is to be understood generally and includes not only a pressure value as such, but all quantities that can be derived from it, such as pressure ratio, a pressure difference, an average of several pressure values ​​or a pressure profile over time, etc.

[0014] The means for determining pressure can be arranged such that the pressure is measured upstream and / or downstream and / or in the dialyzer.

[0015] Preferably, the dialyzer is connected to the dialysate circuit of the dialysis machine, so that fluid is filled from the latter into the dialysate side of the dialyzer.

[0016] Preferably, the liquid with which the dialyzer is filled is dialysate, and particularly preferably the dialysate with which the treatment is then carried out.

[0017] Preferably, however, the test according to the invention to determine whether the correct dialyzer has been used is carried out before the start of the patient's treatment.

[0018] The means for determining pressure and the evaluation device can be designed such that the pressure measurement takes place during and / or after the dialyzer is filled. If the pressure and fill volume are measured during filling, a ratio between these two quantities can be calculated, determined over time, and compared with a corresponding characteristic curve.

[0019] It is also conceivable to fill the dialyzer, preferably its dialysate side, and, once completely filled, to measure the fill volume and the resulting pressure. The ratio of these two values, compared to a standard value, can then be used to verify whether the correct dialyzer was used.

[0020] Pressure measurement can be carried out, for example, using pressure sensors on the dialysis machine, which are preferably already provided on the dialysis machine.

[0021] As stated, the liquid is preferably dialysate.

[0022] The means of filling the dialyzer with fluid can be the dialysate pump of the dialysis machine. This can be a rotary pump, such as a peristaltic pump, so that the amount of dialysate supplied to the dialyzer can be determined by the pump's rotation. A sensor specifically designed to determine the fill level is not required in this case.

[0023] As explained, it is preferably provided that the means for filling the dialyzer are in fluid contact with the dialysate side of the dialyzer.

[0024] In a further embodiment, the present invention relates to a dialysis machine with a dialyzer, wherein the dialysis machine has a device for identifying the dialyzer.

[0025] The device provides that the dialyzer has an electrically conductive element and that it is configured to measure the electrical resistance of the conductive element and that an evaluation device is provided which is configured to compare the measured resistance with a predetermined resistance, wherein the evaluation device is further configured to output a signal which depends on whether the measured resistance matches the predetermined resistance.

[0026] This embodiment can exist in addition to the first embodiment described at the outset.

[0027] For example, it is conceivable to identify the dialyzer by measuring its resistance and, as a fallback solution, to measure the pressure and filling volume, as described above. A reverse approach is also conceivable and encompassed by the invention.

[0028] The electrically conductive element can be integrated into a sticker, which is preferably located on a coupling of the dialyzer.

[0029] It is conceivable, for example, to attach a sticker with an integrated metal strip featuring a defined measuring resistance to the dialyzer coupling after it has locked into place, i.e., after it has connected to the counterpart of the dialyze circuit. This sticker could also be attached to a location other than the dialyzer coupling. The sticker could be straight, curved, ring-shaped, etc.

[0030] Preferably, the device has two wires on the dialysis unit inlet or outlet hose that are in conductive contact with the conductive element in order to measure its resistance. Preferably, the distance between the two measuring wires or pins is always the same, so that the measurement can be taken regardless of the position of the inlet at the coupling.

[0031] The dialysis machine preferably has a dialysate circuit to which the dialyzer is preferably connected for identification purposes and is in fluid communication. This applies to both embodiments according to the invention.

[0032] The measured electrical resistance is compared to a characteristic value of the correct dialyzer, e.g., from a database, and thus its plausibility is checked. If a different value is measured, a message or other signal may prompt the user to check the settings or the dialyzer type. If no value is measured, as is the case with a third-party dialyzer or with older equipment, a message may appear indicating that the measurement cannot be performed.

[0033] The present invention further relates to a method for identifying a dialyzer, wherein the dialyzer is filled with liquid, the fill quantity of liquid in the dialyzer and the pressure representative of the pressure in the filled area of ​​the dialyzer are determined, and the measured fill quantity is related to the measured pressure and compared with a predetermined characteristic curve or with a predetermined characteristic value, wherein a signal is output which depends on whether the determined relationship corresponds to the predetermined characteristic curve or with the predetermined characteristic value.

[0034] As explained, the pressure can be measured upstream and / or downstream and / or within the dialyzer.

[0035] Pressure measurement can be performed during and / or after filling the dialyzer.

[0036] Preferably, for the purpose of identifying the dialyzer, its dialysate side is filled with liquid, preferably with dialysate.

[0037] The method for identifying a dialyzer may have additional features, wherein the dialyzer has a conductive element and the electrical resistance of this conductive element is measured and compared with a predetermined resistance, outputting a signal which depends on whether the measured resistance matches the predetermined resistance.

[0038] It is conceivable that the dialyzer is provided with a sticker that features or consists of the conductive element.

[0039] The resistance can be measured using two wires, pins or the like on the dialysis inlet or outlet hose, which are in conductive contact with the conductive element in order to measure its resistance.

[0040] It should be noted here that the terms "ein" and "eine" do not necessarily refer to exactly one of the elements, although this is a possible interpretation, but can also denote a plurality of elements. Likewise, the use of the plural also includes the presence of the element in question in the singular, and conversely, the singular also includes several of the elements in question.

[0041] Further details and advantages of the invention will be explained in more detail with reference to an exemplary embodiment described below.

[0042] In a first embodiment of the invention, the dialyzer is connected to the dialysate circuit of the dialysis machine before the patient is treated, and the dialysate pump is started. Simultaneously, the pressure at the inlet and / or outlet of the dialyzer is measured, and a ratio is calculated between the volume of dialysate already in the dialyzer and, for example, the inlet pressure. This ratio can be calculated continuously or at specific time intervals.

[0043] It is compared with a characteristic curve or parameters that represent such a ratio for the desired dialyzer.

[0044] If an evaluation unit determines that the measured ratio corresponds to this characteristic curve or the specified value, no signal is sent to the user, nor is it indicated that the dialyzer type used is correct. However, if the evaluation unit determines that this is not the case, a signal is issued from which the user can deduce that the wrong dialyzer type was used. In this case, it is also conceivable that the dialysis machine will prevent treatment, for example, by stopping the pumps and closing valves.

[0045] The identity test of the dialyzer described above preferably takes place before the patient's dialysis treatment. Preferably, the blood pump is not yet in operation, so that the test according to the invention does not affect or change the patient's blood composition in any way.

[0046] In a second embodiment, the dialyzer additionally has an electrically conductive surface, conductor track, etc., which can be integrated into the dialyzer or applied to it, for example, by means of a sticker.

[0047] A measuring device measures the electrical resistance of the electrically conductive surface, conductor track, etc., and compares it with a characteristic value that is typical for the desired dialyzer.

[0048] If an evaluation unit determines that the measured value corresponds to this characteristic value, no signal is sent to the user, nor is it indicated that the dialyzer type used is correct. However, if the evaluation unit determines that this is not the case, a signal is issued from which the user can deduce that the wrong dialyzer type was used. In this case, it is also conceivable that the dialysis machine will prevent treatment, for example, by stopping the pumps and closing valves.

[0049] The present invention can be implemented using only the first embodiment or using both the first and second embodiments. In the latter case, the fill volume / pressure measurement can be used as a fallback if the electrical resistance measurement fails, for example, because the dialyzer is a third-party product, has a defective label, is from a surplus stock, etc. Alternatively, the electrical resistance measurement can be used to identify a dialyzer type, and the fill volume / pressure measurement can then be used to assign a corresponding dialyzer size. Such a combined method allows for the identification of a particularly large number of different dialyzers.

[0050] Depending on the embodiment, the following advantages can be achieved with the present invention: Improved patient safety through reduced risk of user error. The risk of disruption and associated equipment contamination is reduced, preventing patient blood loss. Implementation is possible on various dialysis machines and product families. Cross-compatibility is ensured, allowing continued use of existing dialyzers. Service quality increases due to the new safety measure, enhancing user confidence. In the version with fill volume and pressure measurement: Identification and plausibility checks of third-party dialyzers are also possible. In the version with fill volume and pressure measurement: Development is cost-effective, as existing functions and methods can be utilized. In the version with resistance measurement: Increased quality and a unique selling point.In the embodiment with resistance measurement: The existing production process of the dialyzers remains unchanged and is only extended by affixing the sticker, e.g. in the form of a ring, which extends around the dialyzer coupling or another part of the dialyzer.

Claims

1. Dialysis machine having a dialyzate circuit and having a dialyzer, wherein the dialysis machine has an apparatus for identifying the dialyzer; wherein the apparatus has means for filling the dialyzer with fluid and has means for determining the filling amount of fluid that is filled into the dialyzer; and wherein the apparatus furthermore has means for determining the pressure that is characteristic for the pressure in the filled region of the dialyzer, characterized in that the dialysis machine has an evaluation device that is configured to put the measured filling amount into relationship with the measured value and to compare it with a predefined characteristic curve or with a predefined characteristic value, with the evaluation device furthermore being configured to output a signal that depends on whether the relationship determined coincides with the predefined characteristic curve or with the predefined characteristic value.

2. Dialysis machine in accordance with claim 1, characterized in that the measured pressure is a pressure ratio or a pressure development.

3. Dialysis machine in accordance with claim 1 or claim 2, characterized in that the means for the pressure determination are arranged such that the pressure or the pressure development is measured upstream and / or downstream of and / or in the dialyzer.

4. Dialysis machine in accordance with one of the preceding claims, characterized in that the means for the pressure determination and the evaluation device are configured such that the pressure measurement takes place during and / or after the filling of the dialyzer.

5. Dialysis machine in accordance with one of the preceding claims, characterized in that the fluid is dialyzate; and / or in that the means for filling the dialyzer with fluid is the dialyzate pump of the dialysis machine.

6. Dialysis machine in accordance with one of the preceding claims, characterized in that the dialyzer has a dialyzate side and a blood side separated therefrom by a membrane; and in that the means for filling the dialyzer are in fluid communication with the dialyzate side of the dialyzer.

7. Dialysis machine in accordance with one of the preceding claims, characterized in that the dialyzer is connected to the dialyzate circuit has an electrically conductive element; and in that that the apparatus is configured to measure the electrical resistance of the conductive element; and in that an evaluation device is provided that is configured to compare the measured resistance with a predefined resistance, with the evaluation device furthermore being configured to output a signal that depends on whether the measured resistance coincides with the predefined resistance.

8. Dialysis machine in accordance with claim 7, characterized in that the conductive element is integrated in an adhesive label that is preferably arranged at a coupling of the dialyzer.

9. Dialysis machine in accordance with claim 7 or claim 8, characterized in that the apparatus has two strands at the dialyzate inflow tube or dialyzate outflow tube that are in conductive contact with the conductive element to measure its resistance.

10. Method of identifying a dialyzer using a dialysis machine in accordance with one of the preceding claims, characterized in that the dialyzer is filled with fluid, the filling amount of fluid in the dialyzer and the pressure that is representative for the pressure in the filled region of the dialyzer are determined, and the measured filling amount is put into relationship with the measured pressure and is compared with a predefined characteristic curve or with a predefined characteristic value, with a signal being output that depends on whether the relationship determined coincides with the predefined characteristic curve or with the predefined characteristic value.

11. Method in accordance with claim 10, characterized in that the pressure is measured upstream and / or downstream and / or in the dialyzer; and / or in that the pressure measurement takes place during and / or after the filling of the dialyzer.

12. Method in accordance with one of the claims 10 or 11, characterized in that the dialyzate side of the dialyzer is filled with fluid, preferably with dialyzate, for the purpose of identifying the dialyzer.

13. Method in accordance with one of the claims 10 to 12, characterized in that the dialyzer has a conductive element and the electrical resistance of this conductive element is measured and is compared with a predefined resistance, with a signal being output that depends on whether the measured resistance coincides with the predefined resistance.

14. Method in accordance with claim 13, characterized in that the dialyzer is provided with an adhesive label that comprises or consists of the conductive element.

15. Method in accordance with claim 13 or claim 14, characterized in that the measurement of the resistance is carried out with the aid of two strands at the dialyzate inflow tube or dialyzate outflow tube that are in conductive contact with the conductive element to measure its resistance.