Simulation model for simulating a hose line of a blood leak detector and method for testing a blood leak detector

Abstract

The present invention relates to a simulation model for simulating a hose line, which has: at least one hollow cylindrical section, which is designed to be arranged in a hose receiving part of a blood leakage detector of a blood treatment machine, wherein receiving parts for light sources are respectively provided at the axial ends of the hollow cylindrical section, by means of which light can be introduced into the hollow cylindrical section; at least one light deflection element, which is arranged in the hollow cylindrical section and is designed to deflect the light introduced into the hollow cylindrical section so that the light leaves the hollow cylindrical section outward through at least one opening in the radial outer side of the hollow cylindrical section. The present invention also relates to a method for checking the function of a blood leakage detector by means of a simulation model according to the present invention.

Description

Technical Field

[0001] The invention relates to a simulation model for simulating a hose line to check the function of a blood leakage detector of a blood treatment machine. Background Art

[0002] Modern blood treatment machines usually have different monitoring elements, which monitor the function of the blood treatment machine before and during the treatment. One of these monitoring elements is a blood leakage detector, which monitors the filtrate circuit or plasma circuit of the blood treatment machine for blood leakage.

[0003] As soon as blood components that are not to be removed from the blood by the dialysis machine during treatment are in the filtrate circuit or plasma circuit, there is a blood leak. This can be caused, for example, by a rupture of the filter membrane in the dialysis machine, filter suction or an excessively high blood flow rate. Such blood loss can pose a great risk to the patient if it remains undetected.

[0004] In order to avoid this or to detect this as early as possible, an optical measuring method is performed during the operation of the blood therapy machine with the aid of a blood leak detector to detect turbidity or red staining in the filtrate or plasma. In this case, the following fact is used for the optical detection of hemoglobin in the filtrate or plasma: in the absorption spectrum of hemoglobin in the visible spectral range, the absorption curves of oxygen-poor and oxygen-rich hemoglobin drop sharply in the red wavelength range and are thus much lower than in the green wavelength range between 500 nm and 600 nm.

[0005] The blood leakage detector is usually arranged on a hose pipeline and transmits light of a defined wavelength to a light detector through the hose and thus through the liquid (such as filtrate or plasma) flowing in the hose, and the light detector is usually a phototransistor. In addition, the blood leakage detector usually has a second light detector or phototransistor, which directly receives light and provides a reference value. From the absorption characteristics of the liquid or the corresponding measurement value of the phototransistor, it can be found out whether the liquid contains hemoglobin.

[0006] In the measurement cycle of the blood leak detector, which usually lasts a total of 400 ms, each of the two phototransistors provides two values. This results in four measured values ​​(hereinafter referred to as red measured value, green measured value, green reference value and red reference value), from which a value value and a dimming value can be calculated, which reflect the absorption properties of the solution. The reference value should be as independent of external influences as possible and serve to eliminate aging phenomena of the light source, which is usually an LED, by measuring the direct emission of the signal that is calculated later.

[0007] In normal blood leakage, the turbidity in the hose due to blood cells is still very low and is monitored using a numerical signal calculated by the following formula.

[0008] Amount = ((red measurement value * green reference value) / (green measurement value

[0009] *Red reference value)) / ((Red calibration measurement value*Green calibration reference value)

[0010] / (green calibration measurement value*red calibration reference value))

[0011] This signal is composed of the value of red light and the value of green light. As mentioned above, since hemoglobin causes stronger absorption of green light, the amount value will increase accordingly in normal bleeding.

[0012] In the case of a large blood leak, this results in a turbidity in the hose that is so strong that it causes the light to be completely absorbed, so that the amount value cannot be used to detect a large blood leak, because both the red light and the green light are absorbed by the strong turbidity. Therefore, a dimming value is used to identify a large blood leak, and the dimming value can only be calculated from the value of the red light according to the following formula.

[0013]

[0014] In addition to the current value provided by the phototransistor, calibration values ​​are also used to calculate the amount value and dimming value. These are also four values ​​that are recorded during the calibration process and then saved as constant values. During the calibration, a hose filled with a saline solution, such as sodium chloride solution (NaCl solution), is inserted into the blood leak detector.

[0015] To ensure patient safety, the function of the blood leak detector of a blood therapy machine must also be checked regularly. Conventionally, the blood leak detector is tested manually in this case by guiding different, defined test solutions such as saline, plasma, filtrate, etc. through a hose line provided with the blood leak detector.

[0016] However, this test method is quite consuming, slow and requires relatively many resources due to the required hoses and solutions. In addition, conventional test methods are limited to specific test conditions, which are generated, for example, by saline solution, plasma or filtrate in the hose. Summary of the invention

[0017] The present invention is therefore based on the object of alleviating or eliminating the disadvantages of the prior art. In particular, the present invention is based on the object of providing a faster and more resource-saving testing method and a device for performing such a testing method.

[0018] This object is achieved by a simulation model according to claim 1 and a method according to claim 10. A further aspect of the invention relates to a blood treatment machine, in particular a dialysis apparatus, having a simulation model according to claim 1 .

[0019] The simulation model according to the invention makes it possible to simulate different test conditions, such as filtrate in a hose line or saline solution in a hose line, by means of a single component, without using actual solutions or hose lines. By means of such a simulation model, the function of the blood leak detector can be monitored automatically and / or (fully) automatically.

[0020] According to the present invention, a simulation model for simulating a hose pipeline comprises: at least one hollow cylindrical section, which is designed to be arranged in a hose receptacle of a blood leakage detector, preferably a blood leakage detector of a blood treatment machine, wherein receptacles for respective light sources are respectively provided at the axial ends of the hollow cylindrical section, with the aid of which light can be introduced into the hollow cylindrical section; and at least one light deflection element, which is arranged in the hollow cylindrical section and is designed to deflect the light introduced into the hollow cylindrical section so that the light leaves the hollow cylindrical section outward through at least one opening in the radial outer side of the hollow cylindrical section.

[0021] In this case, the hollow cylindrical section of the simulation model preferably simulates a hose line which would normally be inserted into a hose receptacle of a blood leak detector.

[0022] By means of the light source, light with a predetermined red and / or green component can be introduced into the hollow cylindrical section, so that the absorption properties of a solution, such as a saline solution or plasma or any other solution or fluid can be simulated. Different solutions can be simulated / emulated by setting the mixture of light.

[0023] The light source can be permanently installed in the receiving part of the simulation model, preferably by pressing in or gluing. Alternatively, the light source can also be arranged on and / or associated with the blood treatment machine, and when the simulation model is used, for example, to check the function of a blood leakage detector of the blood treatment machine, the light source is only introduced into the receiving part of the simulation model.

[0024] It has proven to be advantageous that the light deflecting element is a mirror, which is arranged so that it refracts the introduced light and deflects it by approximately 90°. The light introduced by the light source is deflected by the light deflecting element through at least one opening in the hollow cylindrical section of the simulation model to at least one light detector, such as a phototransistor.

[0025] Furthermore, it has proven to be advantageous if two openings, which are preferably located opposite one another, are provided in the radial outer side of the hollow-cylindrical section, between which openings at least one light deflecting element is preferably arranged.

[0026] According to one aspect of the invention, a light source is arranged in each of the receptacles at the axial ends of the hollow cylindrical section, which light source preferably directs red light and / or green light into the hollow cylindrical section. However, it is also possible to arrange only one light source on or at the simulation model. Furthermore, the light source can emit light of any other wavelength, for example light in the visible or invisible range, in the infrared range or in the UV range.

[0027] Preferably, the light source is an LED which is fixedly secured in the receptacle, preferably by means of a press fit and / or adhesive bonding.

[0028] In order to improve the user-friendliness of the simulation model and ensure reliable fixation of the simulation model on the blood leak detector, the simulation model can be additionally provided with a handle section, which is designed to facilitate the user's gripping of the simulation model and preferably extends in an arc or bow shape from a first axial end section of the hollow cylindrical section to a second axial end section of the hollow cylindrical section.

[0029] It has also proven to be advantageous if the simulation model is made of a material that is opaque / impermeable to the light introduced into the hollow cylindrical section and to the ambient light, preferably of metal and / or plastic. The simulation model can be produced by means of an additive or subtractive 3D printing method. Preferably, the material of the simulation model is dark, for example black. This achieves particularly good shielding of the interior of the hollow cylindrical section from disturbing ambient light.

[0030] The simulation model can also additionally have a control device, which controls at least one light source or multiple light sources of the simulation model in an open-loop or closed-loop manner. For example, the mixture of light emitted by the at least one light source or multiple light sources (e.g., a green portion and / or a red portion) can be changed or set by means of the control device.

[0031] Another aspect of the present invention relates to a blood treatment machine, which has a simulation model according to the present invention and a blood leakage detector, wherein the blood leakage detector has at least one light detector, wherein at least one opening in the radially outer side of the hollow cylindrical section of the simulation model and the at least one light detector of the blood leakage detector are arranged relative to each other so that the light introduced into the hollow cylindrical section and deflected by the light deflection element is deflected to the at least one light detector through the at least one opening. Preferably, the light detector is a phototransistor.

[0032] The simulation model can be connected to the blood treatment machine in a detachable or non-detachable manner.

[0033] Another aspect of the invention relates to a method for checking the function of a blood leak detector of a blood therapy machine and / or the function of a blood therapy machine, wherein a simulation model is arranged on the blood leak detector, wherein preferably a hollow cylindrical section of the simulation model is arranged in a tube receptacle of the blood leak detector.

[0034] By means of at least one light source of the simulation model, light with a predetermined red component and / or green component is introduced into the hollow cylindrical section of the simulation model, wherein the red component and / or green component of the light introduced by the light source is set such that when light of a predetermined wavelength is sent into or through the hose and / or the fluid, while at the same time no fluid or a specific fluid (e.g. saline solution, plasma or filtrate) flows through the hose arranged in the hose receptacle, the red component and / or green component corresponds to the red component and / or green component of the reflected light. Thus, the light mixing imitates or simulates the absorption properties of the specific solution.

[0035] Preferably, the red and / or green components of the light introduced by the light source are set such that they correspond to the red and green components of the reflected light when light of a predetermined wavelength is sent into the hose and / or the fluid or through the hose and / or the fluid while a saline solution or blood plasma or a dialysis fluid or a blood plasma with a specific blood component flows through the hose arranged in the hose receptacle. Conventional test conditions (saline solution, blood plasma, dialysis fluid, blood plasma with a specific blood component) can thus be adjusted again with the aid of the simulation model. However, any other test conditions can also be simulated with the aid of the simulation model or the simulation method, since any wavelength of light and / or composition can be used to simulate any absorption properties.

[0036] The dimming values ​​and the amount values ​​to be expected are known for various predefined states or test conditions. These states are, for example: a hose filled with NaCl solution inserted into a blood leak detector, normal bleeding, e.g. in plasma, heavy bleeding, e.g. in plasma, a hose not inserted into a blood leak detector, an empty hose inserted into a blood leak detector, e.g. hemoglobin in plasma, violation of the valid value range, air bubbles in the hose, external light effects on the blood leak detector, simulation of the T0 test (initial test at the start of operation of a blood therapy machine).

[0037] In particular, measured values ​​of red light and green light characterizing a specific state (hereinafter referred to as red measured value and green measured value) are calculated according to the following formula, which are then set by means of a digital-to-analog converter through the light source or LED in the simulation model and result in a quantity value and dimming value associated with the specific state.

[0038]

[0039]

[0040] In this way, states or test conditions can be simulated in the simulation model.

[0041] The blood treatment machine can also additionally have a control device, which open-loop or closed-loop controls at least one light source or multiple light sources of the simulation model. For example, the mixture of light emitted by the at least one light source or multiple light sources (for example a green portion and / or a red portion) can be changed or set by means of the control device.

[0042] The method according to the present invention may have the following steps: connecting the simulation model according to the present invention to a control device, especially when the simulation model itself does not have a control device; optionally, connecting the simulation model to a test control instrument, which is designed to perform tests and with the help of which, for example, specific test conditions can be preset for a user; setting the simulation model on or in a blood leakage detector; synchronizing the frequency of the light emission cycle of at least one light source (or multiple light sources, usually LEDs) with the receiving frequency or measuring frequency of the blood leakage detector, preferably by determining or reading a DB variable through an optical clock; emitting light from at least one light source (or multiple light sources, usually LEDs), which light is transmitted to at least one light detector (or multiple light detectors, usually phototransistors), wherein a desired measurement value or reference value is achieved in order to simulate or imitate the preset test conditions.

[0043] DB variables are variables that can be transferred from a blood therapy machine to a Windows computer via a CAN adapter. They can be manipulated by assigning values ​​to them via scripts or via so-called DB tools in order to make the blood therapy machine accept that a state exists that is not actually applied.

[0044] The method according to the invention can be used to test the functionality of the blood leak detector itself or to check a blood therapy machine with regard to its reaction to different (alarm) states in the blood leak detector.

[0045] At this point it should be noted that the terms "a" and "an" do not necessarily refer to exactly one of an element, although this is a possible embodiment, but may also refer to a plurality of elements. The use of the plural number also includes the element in question being present in the singular, and conversely the singular number also includes a plurality of the elements in question. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Further details and advantages of the invention are explained in greater detail with reference to the exemplary embodiments shown in the drawings.

[0047] The accompanying drawings show:

[0048] Figure 1A schematic diagram illustrating the functionality of a blood leak detector is shown;

[0049] Figure 2 A cross-sectional view showing a blood leak detector;

[0050] Figure 3 shows a schematic diagram illustrating the functionality of a simulation model according to the invention;

[0051] Figure 4 A top view showing the front side of a simulation model according to a preferred embodiment of the present invention;

[0052] Figure 5 A top view showing the rear side of a simulation model according to a preferred embodiment of the present invention;

[0053] Figure 6 The device is shown in a state where it is set on the blood leakage detector. Figure 4 and 5 Simulation models in ; and

[0054] Figure 7 The device is shown in a state where it is set on the blood leakage detector. Figure 4 and 5 Figure 2. Simulation model in which the blood leak detector is turned off.

[0055] In the figures, the same reference signs denote identical or functionally identical components. DETAILED DESCRIPTION

[0056] As in Figure 1 As shown in FIG. 1 , the blood leak detector 1 has a tube receptacle 2 , in which a tube or a tube line can be arranged.

[0057] The blood leakage detector 1 also has an LED 3 and two phototransistors 4 and 5. The light emitted by the LED 3 is Figure 1 Indicated by arrows.

[0058] Light is emitted by the LED 3 through the hose receptacle 2 and any hose arranged therein to the phototransistor 4. The phototransistor 4 detects the corresponding measured value. In addition, light is emitted by the LED 3 directly to the phototransistor 3. The phototransistor 3 detects the corresponding reference value.

[0059] As from Figure 2 As can be seen in the sectional view of the blood leak detector in , the blood leak detector 1 further comprises a door or flap 6 which can be closed after the tube has been inserted into the tube receptacle 2 so that the tube is held securely in the tube receptacle 2 .

[0060] Figure 3A simulation model 10 arranged in the blood leakage detector 1 is schematically shown, which has two LEDs 7 and 8 and a mirror 9. A hollow cylindrical section of the simulation model (not shown here) is arranged in the tube receptacle 2.

[0061] The light (indicated by the arrows) introduced by the LEDs 7 and 8 into the hollow cylindrical section of the phantom is deflected by the mirror 9 essentially at a right angle and directed to the phototransistors 4 and 5 of the blood leak detector.

[0062] Figure 4 The front side of the simulation model 10 is shown in a top view. The simulation model has a hollow cylindrical section 11, at the axial ends of which a receptacle 12 is provided for receiving the LEDs 7 and 8. Two openings 13, 14, which are located opposite each other, are formed in the radial outer side of the hollow cylindrical section, through which light can leave the hollow cylindrical section 11 to the outside.

[0063] The simulation model 10 also has an arcuate handle section 15 which extends from one receptacle 12 to the other receptacle 12 .

[0064] exist Figure 5 Mirror 16 can be seen in FIG. 1 , which is arranged between opening 13 and opening 14 in such a way that the light is deflected substantially by 90° and is deflected through opening 13 or 14 .

[0065] In the embodiment shown, the simulation model 10 is produced in one piece from a black material by means of an additive 3D printing method.

[0066] Figure 6 The simulation model 10 is shown, which is arranged on the blood leak detector 1. The door 6 of the blood leak detector 1 is open, so that the hollow cylindrical section 11 arranged in the tube receptacle 2 is visible.

[0067] exist Figure 7 In the illustration of , the door 6 of the blood leak detector 1 is closed, so that the hollow cylindrical section 11 arranged in the tube receptacle 2 is firmly held in the blood leak detector.

Claims

1. A simulation model (10) for simulating a hose pipeline, comprising: At least one hollow cylindrical section (11) is designed to be arranged in a tube receiving portion (2) of a blood leak detector (1), wherein receiving portions (12) are respectively provided at the axial ends of the hollow cylindrical section (11), the receiving portions are respectively used for light sources, by means of which light can be introduced into the hollow cylindrical section (11), and At least one light deflecting element is arranged in the hollow cylindrical section (11) and is designed to deflect light introduced into the hollow cylindrical section (11) so that the light leaves the hollow cylindrical section (11) outward through at least one opening (13, 14) in the radial outer side of the hollow cylindrical section (11), characterized in that A light source is respectively arranged in the receptacle (12) at the axial ends of the hollow cylindrical section (11).

2. The simulation model (10) according to claim 1, It is characterized in that The at least one hollow cylindrical section is designed to be arranged in a tube receptacle (2) of a blood leakage detector (1) of a blood treatment machine.

3. The simulation model (10) according to claim 1, It is characterized in that The light source directs red and / or green light into the hollow cylindrical section (11).

4. The simulation model (10) according to claim 1, It is characterized in that The light deflecting element is a mirror (16) which is arranged such that it deflects the introduced light substantially by 90°.

5. The simulation model (10) according to any one of the preceding claims, It is characterized in that Two openings (13, 14) are provided in the radial outer side of the hollow cylindrical section (11).

6. The simulation model (10) according to claim 5, It is characterized in that The openings are located opposite each other.

7. The simulation model (10) according to claim 5, It is characterized in that The at least one light redirecting element is disposed between the openings.

8. The simulation model (10) according to claim 1, It is characterized in that The light source is an LED (7, 8) which is firmly fixed in the receiving portion (12).

9. The simulation model (10) according to claim 8, It is characterized in that The LED is firmly fixed in the receiving portion (12) by press-fitting and / or bonding. 10 . The simulation model ( 10 ) as claimed in claim 1 , further comprising a handle section ( 15 ) which is designed to facilitate gripping of the simulation model ( 10 ) by a user.

11. The simulation model (10) according to claim 10, It is characterized in that The handle section extends in an arcuate or bow-shaped manner from a first axial end section of the hollow cylindrical section (11) to a second axial end section of the hollow cylindrical section (11).

12. The simulation model (10) according to any one of the preceding claims, It is characterized in that The simulation model (10) is made of a material which is opaque to the light introduced into the hollow cylindrical section (11) and to the ambient light.

13. The simulation model (10) according to claim 12, It is characterized in that The simulation model (10) is made of metal and / or plastic.

14. A blood treatment machine, comprising a simulation model (10) according to any one of the preceding claims and a blood leakage detector (1), wherein the blood leakage detector comprises at least one light detector. It is characterized in that At least one opening (13, 14) in the radial outer side of the hollow cylindrical section (11) of the simulation model (10) and the at least one light detector of the blood leakage detector (1) are arranged so that the light introduced into the hollow cylindrical section (11) deflected by the light deflection element is deflected to the at least one light detector through the at least one opening (13, 14).

15. The blood treatment machine according to claim 14, It is characterized in that The simulation model (10) is detachably or non-detachably connected to the blood treatment machine.

16. A method for checking the function of a blood leakage detector (1) of a blood treatment machine, the method comprising the following steps: A simulation model (10) according to any one of claims 1 to 13 is arranged on the blood leak detector (1).

17. The method according to claim 16, It is characterized in that The hollow cylindrical section (11) of the simulation model (10) is arranged in the tube receptacle (2) of the blood leak detector (1).

18. The method according to claim 16, further comprising the steps of: Light having a predetermined red component and / or green component is introduced into the hollow cylindrical section (11) of the simulation model (10) by means of at least one light source, wherein the red component and / or green component of the light introduced by the light source is set so that when light of a predetermined wavelength is sent into or through a hose and / or a fluid in the hose receptacle (2) and when either no fluid flows or a specific fluid flows through the hose, the red component and / or green component corresponds to the red component and / or green component of the reflected light.

19. The method according to claim 18, It is characterized in that The red component and / or green component of the light introduced by the light source is set so that when light of a predetermined wavelength is sent into the hose and / or the fluid or passes through the hose and / or the fluid and a saline solution or a dialysis liquid flows through the hose arranged in the hose receiving portion (2), the red component and / or the green component corresponds to the red component and the green component of the reflected light.

20. The method according to claim 18, It is characterized in that The red component and / or green component of the light introduced by the light source is set so that when light of a predetermined wavelength is sent into the hose and / or the fluid or passes through the hose and / or the fluid and blood plasma flows through the hose arranged in the hose receiving portion (2), the red component and / or the green component corresponds to the red component and green component of the reflected light.

21. The method according to claim 18, The red component and / or green component of the light introduced by the light source is set so that when light of a predetermined wavelength is sent into the hose and / or the fluid or passes through the hose and / or the fluid and blood plasma with a specific blood component flows through the hose arranged in the hose receiving portion (2), the red component and / or the green component corresponds to the red component and green component of the reflected light.

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