EXTRACORAL BLOOD CONDITIONING SET AND BLOOD TREATMENT MACHINE

Description

[0001] The present disclosure relates to an extracorporeal blood treatment machine, in particular a dialysis machine. Background of the invention

[0002] In extracorporeal blood treatment (e.g., hemodialysis), the patient's blood is bathed in the so-called dialysis fluid within the dialyzer. The blood is pumped from the patient to the dialyzer via an arterial tubing system and then returned to the patient via a venous tubing system. The blood pump is typically located within the arterial tubing system.

[0003] Before entering the dialyzer, the patient's blood is (partially) continuously mixed with heparin or an alternative anticoagulant (e.g., citrate) to prevent clotting of the dialyzer. This is done, for example, using a syringe pump containing the medication. The syringe pump is often an integral part of the dialysis machine. State of the art

[0004] Conventional dialysis machines often use a syringe pump for administering the anticoagulant. This pump can be external or integrated as an integral part of the dialysis machine. Typically, the syringe pump is connected to the bloodstream via a separate tube with a Luer-lock connector. For example, German patent application DE 10 2011 008 856 A1 discloses a tubing system for a dialysis machine that has one connection point for administering heparin and a separate connection point for administering citrate. Both anticoagulants are administered to the blood tubing system via their own separate pumps or syringes.

[0005] Similarly, DE 42 30 513 C1 discloses a device for removing aluminum ions from blood. Here too, the anticoagulant can be supplied to the bloodstream via an additional pump to prevent clogging of the dialyzer.

[0006] German patent DE 10 2017 210 134 A1 discloses a system for extracorporeal blood treatment. In addition to the blood pump for promoting blood flow, a second additional pump is arranged to supply the anticoagulant, in particular the citrate solution, to the bloodstream.

[0007] FR 2 639 831 A1 discloses a device for infusing medications, in particular heparin, into the negative pressure area of ​​an extracorporeal blood circuit, in particular an extracorporeal blood circuit of a dialysis device, with a reservoir for the medications and a supply line from the reservoir to the extracorporeal blood circuit. Brief description of the invention

[0008] Based on the current state of the art, the syringe pump has the disadvantage of being a relatively complex and expensive component. Furthermore, the syringe pump requires a significant amount of space both inside and outside the dialysis machine at the front of the unit.

[0009] The object of the invention is therefore to avoid or at least mitigate the disadvantages of the prior art. In particular, it aims to provide a blood supply set that can administer an anticoagulant cost-effectively and reliably during dialysis therapy without the need for a conventional syringe pump. It is of particular importance for patient safety that the anticoagulant is administered with a precisely defined delivery volume (mass flow rate), even when the syringe pump is not used.

[0010] This problem is solved in an extracorporeal blood treatment machine according to claim 1. Further optional features are claimed in dependent claims 2-5.

[0011] The arterial blood line of the blood line set comprises a section with a constricted flow cross-section, a section with a constant, constricted flow cross-section, and a section with a widening flow cross-section. According to the invention, the fluid supply line is connected to the section with a constant flow cross-section. When blood flows through the blood line, it is accelerated through the constricted section, causing the pressure in the blood line to decrease. Along the section with a constant flow cross-section, the blood flows at a substantially constant negative pressure, allowing fluid to be drawn in through the fluid supply line. Due to the constant negative pressure in the section with a constant flow cross-section, the suction effect, and thus the delivery rate of the anticoagulant, can be precisely determined and adjusted.

[0012] This has the advantage that the medical fluid can be introduced into the bloodstream in the arterial blood vessel by utilizing the Venturi effect, and no additional pump is needed to deliver the medical solution.

[0013] According to the invention, a fluid supply line valve assembly is arranged between the at least one connection section and the container connection or the fluid container. This assembly is designed to regulate or control the fluid supply flow, which is effected exclusively by utilizing a suction pressure (negative pressure) generated in the fluid supply line by the blood flow in the arterial blood vessel. The blood treatment machine according to the invention thus allows a controllable supply of a medical fluid into the bloodstream without requiring an additional pump.

[0014] According to the invention, the connection section is arranged upstream of the pump between the patient access point and the pump on the arterial blood line. When the connection section is arranged at this location, it can also be designed as a T-piece with a substantially constant cross-section in the direction of blood flow, which reduces manufacturing costs.

[0015] In a preferred embodiment, the control device can control the fluid supply line valve assembly based on the blood flow, the blood flow pressure, and a target flow rate of a medical fluid stored in the fluid reservoir by opening the fluid supply line valve assembly for a predetermined opening duration and at a predetermined opening frequency. Thus, the flow rate or the amount of medical fluid added can be precisely controlled. The control device can determine the opening duration and the opening frequency by using a code, in particular a Barker code. In a preferred embodiment, a Barker code of length three with the encoding "+1 +1 -1" can be used, where "+1" can represent a comparatively long opening duration of the valve with a short opening frequency or long period, and "-1" can represent a shorter opening duration with a higher opening frequency or long period.shorter periods are possible.

[0016] According to the invention, the blood treatment machine can have a detection unit which detects the connection status of the fluid supply line with the fluid supply line valve assembly and outputs a signal, for example optical, acoustic, or capacitive, depending on the detection result. This allows the machine to detect if the fluid supply line is not inserted and the fluid supply line valve assembly remains permanently open, thus preventing an unintentionally high and potentially patient-endangering administration of the medical fluid.

[0017] In a further embodiment according to the invention, a flow sensor, preferably non-invasive, and in particular an ultrasonic sensor, can be arranged on the fluid supply line to determine the solution flow rate in the fluid supply line. The ultrasonic sensor can be integrally formed with the fluid supply line valve assembly and simultaneously detect the solution flow rate and the connection status of the fluid supply line with the fluid supply line valve assembly. The placement of the flow sensor allows for precise monitoring of the flow rate of the medical fluid, and the integration of flow rate monitoring and connection status detection enables a reduction in the number of components and system complexity.Additionally, the positioning of the flow rate sensor also has the advantage that air in the fluid supply line can be detected, thus enabling the detection of a possible emptying of a container holding the medical fluid.

[0018] According to the invention, a filter unit, in particular a so-called airstop filter, can be additionally arranged on the fluid supply line, which prevents air from flowing into the fluid supply line. The filter unit can either be integrated as a fixed component in the fluid supply line or be designed as a separate intermediate piece.

[0019] As an alternative to positioning the flow sensor on the fluid supply line, in a further embodiment of the invention, the flow sensor can be located downstream of the connection point on the arterial blood line. Flow monitoring can then be performed by using the difference between a first and a second blood flow rate, taking into account the opening duration of the fluid supply line valve assembly. When the fluid supply line valve assembly is closed, the flow sensor can measure the first blood flow rate, and when the fluid supply line valve assembly is open, the flow sensor can measure the second blood flow rate. This has the advantage that, in addition to determining the fluid flow rate, the flow sensor can also be used to detect any air that may be present in the bloodstream.

[0020] In a further embodiment of the invention, the connection point can be attached to the arterial blood line via a detachable connection, in particular a Luer-lock connection. The connection point, including the fluid supply line, is designed as a separate component, which has the advantage that conventional tubing sets do not need to be modified.

[0021] As an alternative to the fluid supply line valve device, which can only be operated in the closed and open states, a proportional valve can also be used in an embodiment according to the invention, which can control the flow rate of the medical fluid by changing the cross-sectional area of ​​the fluid supply line with any desired precision. Brief description of the characters

[0022] Fig. 1 is a representation to illustrate a system structure of a dialysis machine according to a first embodiment of the present disclosure; Fig. 2 is a schematic detail view of a connection section of the dialysis machine according to the first embodiment; Fig. 3 This is a representation illustrating the system structure of a dialysis machine according to a modification of the first embodiment of the present disclosure; this machine is not part of the claimed invention. Fig. 4 This is a representation illustrating the system structure of a dialysis machine according to an example of the present disclosure. This machine is not part of the claimed invention.

[0023] Fig. 1 Figure 1 is a diagram illustrating the schematic setup of a dialysis machine 1 with an extracorporeal blood line set 2 according to an embodiment of the present disclosure. The line set 2 includes an arterial blood line 3, which comprises a first arterial blood line section 4 and a second arterial blood line section 5, a venous blood line 6, a pump 7, a dialyzer 8, a control device 9, a branch / connection point / connection section 10, a valve 11, a container 12, and a fluid supply line 13. The dialyzer 8 is here an example of "a device" and serves to purify the blood of a patient P.

[0024] At one end of the first arterial blood line segment 4, a line set inlet 14 is formed, through which the patient's blood P to be purified flows into the line set 2, corresponding to the first patient access point. The other end of the first arterial blood line segment 4 is connected to an inlet side of the pump 7, or is in the pump's inlet. An outlet side of the pump 7 is connected to an end of the second arterial blood line segment 5. In the case of a rotor / peristaltic pump, as is typical for blood pumps, the arterial blood line 3 can also be looped or threaded into the blood pump 7, resulting in the first and second arterial blood line segments 4 and 5 (as a single unit). The other end of the second arterial blood line segment 5 is in turn connected to an inlet of the dialyzer 8. An outlet of the dialyzer 8 is connected to an end of the venous blood line 6.The purified blood is returned to patient P via a line outlet 15, which is located at the other end of the venous blood line 6 and corresponds to another patient access point. In the preferred embodiment, the connections through which the second arterial blood line section 5 and the venous blood line 6 are each connected to the dialyzer 8 are designed as so-called Luer-lock connections.

[0025] In the preferred embodiment, the pump 7 is designed as a peristaltic pump, so that the patient's blood is pumped from the patient P to the dialyzer 8 by the rotation of the pump 7. When the pump 7 is operated by a control command from the control device 9, a vacuum is created in the first arterial blood vessel section 4, so that the blood to be purified from the patient P is drawn in and flows into the first arterial blood vessel section 4 via the line inlet 14. The pump 7 pumps the blood through the second arterial blood vessel section 5 to the dialyzer 8. In the dialyzer 8, the blood is surrounded by a dialyzing fluid and thereby purified.The operation of pump 7 creates an overpressure in the blood flow direction downstream of pump 7 in the second arterial blood conduit section 5, the dialyzer 8 and the venous blood conduit 6, which causes the blood to flow from pump 7 through the second arterial blood conduit section 5, the dialyzer 8 and the venous blood conduit 6 back to patient P.

[0026] Furthermore, a connection point 10 is formed in the extracorporeal tubing set 2. This connection point 10 is arranged between the tubing set inlet 14 and the pump 7 on the first arterial blood line segment 4 and is essentially designed in the form of a Venturi tube / Venturi nozzle, such that the cross-section of the connection point 10 decreases along the direction of blood flow. At a point where the cross-section of the connection point 10 is minimal, one end of the fluid supply line 13 branches off. The connection point 10 according to the exemplary embodiment is shown schematically in Fig. 2 As shown here, the connection point 10, designed in the form of a Venturi nozzle, has a flow-cross-sectional constriction section 10a, a section with a constant flow cross-section 10b, and a flow-cross-sectional expansion section 10c in the direction of flow. The flow-cross-sectional constriction section 10a and the flow-cross-sectional expansion section 10c are each in fluid communication with the first arterial blood conduction section 4. The fluid supply line 13 is connected to the section with a constant flow cross-section 10b. When blood flows through the first arterial blood conduction section 4 into the connection point 10, it is accelerated via the flow-cross-sectional constriction section 10a. Due to this acceleration, the pressure in the blood flow decreases. Along the section with constant flow cross-section 10b, the blood therefore flows at constant negative pressure.

[0027] The other end of the fluid supply line 13 is connected to the container 12, which holds an anticoagulant. The anticoagulant is, in this context, an example of a "medical fluid." When the pump 7 is operated as described above, the blood flows through the tubing set 2, and the anticoagulant is drawn from the container 12 to the connection point 10 and ultimately into the first arterial blood vessel 4 due to the design of the connection point 10 and the resulting Venturi effect. In addition to the Venturi effect, the anticoagulant also flows from the container 12, through the connection point 10, into the first arterial blood vessel 4 due to the negative pressure described above.

[0028] A valve 11 is arranged on the fluid supply line 13 between the connection point 10 and the container 12. The valve 11 is an example of a "fluid supply line valve assembly" and is configured to open or close the flow of the anticoagulant from the container 12 to the connection point 10 in response to a control command from the control device 9. In the first embodiment, the valve 11 is designed as a pinch valve.

[0029] In other words, it shows Fig. 1 For example, consider patient P, from whom blood is drawn via arterial line 3 using pump 7. This blood then flows through line 3 to dialyzer 8. After purification there, the blood is returned to patient P via venous line 6. The arterial line 3 contains connection point 10, to which fluid supply line 13 is attached. Fluid supply line 13 leads to container 12, which holds the anticoagulant. Element 11 is designed as a valve 11, preferably a pinch valve or clamp, and allows or prevents the flow of the anticoagulant through fluid supply line 13. In other words, the flow of the anticoagulant can be regulated via valve 11. Connection point 10 has a change in cross-section in the direction of blood flow. The fluid supply line 13 branches off at the narrowest point.According to the Venturi principle, the anticoagulant is drawn from the container 12 through this fluid supply line 13 as soon as the blood flows through the arterial blood line 3. In addition to the Venturi effect, the negative pressure in the arterial blood line 3, which is created by the pump 7, also plays a role in the aspiration of the anticoagulant.

[0030] In the line set 2 according to the first embodiment, a detection unit in the form of an ultrasonic sensor 16 (not in) is additionally integrally integrated on the valve 11. Fig. 1 The ultrasonic sensor 16 (as shown) is arranged optically and detects the connection status of the fluid supply line 13 with the valve 11. Based on this detection status, it outputs a signal. The ultrasonic sensor 16 is connected to the control device 9. If the fluid supply line 13 is not correctly connected to the valve 11, the ultrasonic sensor 16 outputs a signal to the control device 9, which then closes the valve 11 and / or stops the pump 7, thus preventing an unintentionally high and potentially dangerous administration of the anticoagulant. The ultrasonic sensor 16 is shown here only as an example of a "detection unit".

[0031] In other words, to ensure safe and correct administration of the anticoagulant, the pinch valve 11 can have a detection unit in its receptacle for the fluid supply line 13. This unit can determine, for example, optically, acoustically, or capacitively, whether the fluid supply line 13 has been correctly inserted. Failure to insert the fluid supply line 13 into the valve 11 would otherwise be equivalent to the valve 11 remaining permanently open, resulting in an unintentionally high and potentially dangerous administration of the anticoagulant.

[0032] In order to monitor the correct administration of the anticoagulant, the ultrasound sensor 16 in the first embodiment is configured to determine, in addition to detecting the connection state, a flow rate of the anticoagulant in the fluid supply line 13 non-invasively, e.g. in the form of a transit time difference measurement.

[0033] If the ultrasonic sensor 16 is integrally formed on the valve 11, it can also detect air in the fluid supply line 13. If, due to the operation of the pump 7, the anticoagulant has completely flowed out of the container 12 after a certain time, air can be drawn into the fluid supply line 13. To prevent air infusion into the patient P's blood, the control device 9 closes the valve 11 as soon as the ultrasonic sensor 16 detects air in the fluid supply line 13. Alternatively or additionally, the pump 7 can then also be stopped.

[0034] In other words, the invention, according to the exemplary embodiment, provides for determining the flow rate of the anticoagulant. This is preferably achieved by non-invasive flow measurement at the fluid supply line 13. Ultrasonic flow measurement in the form of a transit-time difference measurement is conceivable. The ultrasonic sensor 16 is integrated into the valve 11. In this case, the valve 11 performs the following tasks: Intake of the fluid supply line 13 Squeezing of the fluid supply line 13 Detection of the fluid supply line 13 Flow rate determination in the fluid supply line 13

[0035] In this embodiment, the ultrasonic sensor 16 is used for both flow rate determination and connection status detection. The ultrasonic sensor 16 on the fluid supply line 13 also has the advantage of detecting air in the fluid supply line 13. If the container 12 runs empty, the ultrasonic sensor 16 detects air in the fluid supply line 13, whereupon the valve 11 closes, thus preventing air infusion.

[0036] As described above, in this embodiment the flow rate of the anticoagulant is controlled by the control device 9 through the periodic opening and closing of the valve 11. In this embodiment, the valve 11 additionally includes a spring-loaded element that holds the valve 11 in the closed position when no control command is received from the control device 9. When the control device 9 determines that the valve 11 should be opened, an actuator, preferably electromagnetic, is moved against the restoring force of the spring-loaded element, thus opening the valve 11.

[0037] In the exemplary embodiment, the control device 9 controls the flow rate of the anticoagulant based on the set pumping power of the pump 7 by controlling an opening duration and an opening frequency of the valve 11. The product of the opening duration and the opening frequency of the valve 11 is proportional to the flow rate of the anticoagulant through the fluid supply line 13.

[0038] In other words, according to the invention, the anticoagulant is added from the container 12 through the fluid supply line 13 periodically and in pulses by briefly opening the valve 11. The flow rate / amount added depends on the set blood flow of the pump 7 as well as on the opening duration and the opening frequency of the valve 11. The product of the opening duration and the opening frequency is called the duty cycle, which in turn is proportional to the amount added. Furthermore, the pressure present in the first arterial blood line segment 4 may also play a role, so that this can also be taken into account according to the present invention. Pressure measurements are already performed in the blood lines 4, 5, and 6 on conventional dialysis machines, so the pressure can easily be used to precisely adjust the addition rate.Furthermore, valve 11 is closed by a spring return force as standard to prevent continuous intake of the anticoagulant. The addition is regulated by the control device 9, taking into account the blood flow, pressure, and the target flow rate of the anticoagulant.

[0039] To detect any deviation from the proper functioning of valve 11, the anticoagulant is added in a coded manner. In the first embodiment, a Barker code of length three, consisting of "+1 +1 -1", is predefined by the control device 9 and used to control valve 11. "+1" represents a comparatively long opening duration of valve 11 with a short opening frequency or long period. Conversely, "-1" represents a shorter opening duration with a higher opening frequency or shorter period, whereby the duty cycle remains the same in both cases, and thus the amount of anticoagulant added is not changed.

[0040] During operation, the ultrasonic sensor 16 now detects a flow sequence during flow measurement, as described above, and compares it with the predetermined Barker code. If the valve 11 is functioning correctly, the detected flow sequence corresponds to the Barker code.

[0041] In other words, if the valve 11 additionally has the ultrasonic sensor 16 for flow measurement, the aforementioned Barker code must also be detectable when the valve 11 is functioning. This means that "+1 +1 -1" means "long flow, long flow, short flow".

[0042] In this embodiment, the fluid supply line 13 is automatically filled initially upon connection to the tubing set 2 to prevent air infusion during subsequent therapy. Ideally, this occurs during the so-called priming process by opening the valve 11, which aims to purge the blood tubing set 2 of air before connecting it to the patient P. Modification of the exemplary embodiment

[0043] The following is a modification of the exemplary embodiment with reference to Fig. 3 described. Fig. 3 Figure 1 shows a setup of a dialysis machine 101 with a modified extracorporeal blood line set 102. The setup and function of the modified line set 102 essentially correspond to the extracorporeal blood line set 2 according to the exemplary embodiment, which is why a description of it is not repeated and only the differences are highlighted below.

[0044] As in Fig. 3 As can be seen, in the modified embodiment of the tubing set 102, the connection point 10 is located on the second arterial blood vessel segment 5 between the pump 7 and the dialyzer 8. If the connection point 10 is located downstream of the pump 7 in the blood flow direction, the anticoagulant flows from the container 12 to the connection point 10 and into the second arterial blood vessel segment 5 solely due to the Venturi effect.

[0045] In the modified embodiment, the flow rate of the anticoagulant is therefore controlled as a function of the pressure present in the second arterial blood vessel section 5, in contrast to the embodiment in which the pressure in the first arterial blood vessel section 4 is taken into account.

[0046] In other words, an unused, alternative position for the Venturi nozzle 10 is provided in the second arterial blood vessel segment 5. Since the nozzle 10 is positioned downstream of the pump 7, there is an overpressure in the area of ​​the second arterial blood vessel segment 5 where the nozzle 10 is located, so that the aspiration of the anticoagulant from the container 12 through the fluid supply line 13 is caused solely by the Venturi effect.

[0047] The following is a description of a Fig. 4 The illustrated dialysis machine 201 is described. The design and operation of the dialysis machine 201 essentially correspond to the dialysis machine 1 according to the exemplary embodiment, which is why a description of it is not repeated and only the differences are highlighted below.

[0048] In this unclaimed example, the connection point / connection section 210, unlike in the exemplary embodiment, is designed as a simple T-piece with a substantially constant cross-section in the direction of blood flow. The fluid supply line 13 is arranged to branch off from it in order to supply the medical fluid to the bloodstream. If the connection point 210 is designed as the T-piece, it must be located in the first arterial blood vessel section 4. The fluid is drawn from the container 12 through the fluid supply line 13 into the first arterial blood vessel section 4 solely due to the negative pressure generated by the pump 7 in the first arterial blood vessel section 4.

[0049] The present invention has been described using an exemplary embodiment. However, the present invention is not limited to this.

[0050] In this embodiment, the nozzle-shaped connection point 10 is an integral part of the tubing set 2 in the arterial blood line 3. However, the connection point 10, including the fluid supply line 13, can also be designed as an additional, separate component (disposable). For example, the connection point 10 can be installed between the second arterial blood line segment 5 and the dialyzer 8 via a Luer-lock connection. The advantage of this is that conventional tubing sets do not need to be modified.

[0051] Furthermore, the valve 11 is designed as a valve with only open and closed states. However, as an alternative to the valve 11 with only two states, a proportional valve can also be used. This can, preferably by precisely compressing a section of the fluid supply line 13, change the cross-section of the fluid supply line 13 and thus control the flow rate of the anticoagulant. The specific design of the valve 11 is not relevant to the invention; what matters is merely the fact that it can be used to regulate the flow of the anticoagulant through the fluid supply line 13.

[0052] The ultrasonic sensor 16 is arranged as a flow rate sensor on the fluid supply line 13. However, another non-invasive sensor can also be used to measure the flow rate. Alternatively, the ultrasonic sensor 16 can also be located downstream of the anticoagulant connection point 10 on the arterial blood line 3. Without the addition of the anticoagulant, the sensor measures an initial blood flow rate. Upon addition of the anticoagulant, the sensor 16 measures a second blood flow rate. The difference between the first and second blood flow rates, taking into account the addition duration, represents the flow rate of the anticoagulant from the container 12.Furthermore, the amount of anticoagulant added could also be determined by means of a level sensor in / on the container or by monitoring the weight of the container 12.

[0053] The ultrasonic sensor 16 serves as a detection unit for recording the connection status between the fluid supply line 13 and the valve 11. However, the detection unit can also be implemented by a separate detection unit, for example optical, acoustic or capacitive.

[0054] The ultrasonic sensor 16 is integrally formed on the fluid supply line 13 at the valve 11. Alternatively, the ultrasonic sensor 16 can also be arranged as a separate sensor device.

[0055] The ultrasonic sensor 16 is used to detect when the container 12 runs dry. Additionally or alternatively, the fluid supply line 13 can be equipped with a so-called airstop filter. These filters are well-known in infusion technology and prevent infusion systems from running dry. Such a filter can be located between the fluid supply line 13 and the container 12. It can either be an integral part of the fluid supply line or a separate intermediate piece.

[0056] To monitor the correct administration of the anticoagulant, a Barker code with a length of three is used. However, Barker codes of other lengths or other coding systems can of course also be used.

[0057] It should be noted that other common elements in Fig. 1Although not shown, components are nevertheless taken into account by the invention. These include, for example, air detectors, air traps, addition and removal points, clamps or valves, non-optical sensors (e.g., pressure sensors) and optical sensors (e.g., for determining hematocrit).

Claims

1. An extracorporeal blood treatment machine (1, 101, 201), in particular a dialyzer, having an extracorporeal blood line set (2, 102, 202), comprising: an arterial blood line (3) having a distal patient access and a proximal device port, preferably a dialyzer port, between which a blood pump (7) for delivering blood from a patient (P) to the device (8), preferably a dialyzer, is arranged, a venous blood line (6) having a distal patient access and a proximal device port, preferably a dialyzer port, and at least one fluid supply line (13) which is connected to the arterial blood line (3) in a port section (10, 210) of the arterial blood line (3) that is connected upstream of the blood pump (7) and at one end includes a container port or a fluid container (12), a fluid supply line valve unit (11) between the at least one port section (10, 210) and the container port or the fluid container (12) which fluid supply line valve unit is configured to regulate or control the fluid supply flow, characterized in that the fluid supply flow is effectuated exclusively using a suction pressure in the fluid supply line (13) generated by the blood stream in the arterial blood line (3, 6) and that the port section (10, 210) is formed in the shape of a Venturi tube.

2. The blood treatment machine (1, 101, 201) according to claim 1, further comprising a control device (9) which is configured to control the fluid supply line valve unit (11) on the basis of the blood stream, the pressure of the blood stream and a target flow rate of a medical fluid stored in the fluid container (12) by opening the fluid supply line valve unit (11) for an opening time and at an opening frequency.

3. The blood treatment machine (1, 101, 201) according to claim 2, characterized in that the control device (9) determines the opening time and the opening frequency by using a coding, especially a Barker code.

4. The blood treatment machine (1, 101, 201) according to any of claims 1 to 3, characterized in that the fluid supply line valve unit (11) includes a detection unit which detects, for example, optically, acoustically or capacitively, a connection state of the fluid supply line (13) with the fluid supply line valve unit (11), and, in response to the detection result, outputs a signal when the fluid supply line (13) is not connected to the fluid supply line valve unit (11).