Method for sterilizing a medical device and medical device

Abstract

The present disclosure relates to a method for disinfecting a medical device (2; 102) in the at least one temperature measurement section, in which the temperature (T7; t1, T3, T6.2) associated with the at least one predetermined volume, calculating a temperature-dependent and time-dependent first mortality of a germ potentially present in the at least one temperature measurement section, by means of which the temperature (T2, T3, T4, T5, T6, T8, T9, T10; at least one temperature-dependent and time-dependent second mortality of the pathogen potentially present in at least one predetermined volume is calculated (T1, T2, T4, T5, T6.1-T10.1, T7.2-T10.2), (T1, T2, T4, T5, T6.1-T10.1, T7.2-T10.2); and when the first mortality reaches or exceeds the first threshold value and / or the at least one second mortality reaches or exceeds the second threshold value and / or the first mortality and the at least one second mortality are controlled by the control means (8; 108) reaches or exceeds the average value calculated by the control means (8; and 108) when a predetermined third threshold value is determined, the disinfection is ended. The present disclosure also relates to a corresponding medical device (2; 102) for a vehicle.

Description

Technical Field

[0001] The present disclosure relates to a method for disinfecting a medical device, preferably a dialysis machine, wherein a disinfection fluid is heated, introduced into a fluid line system of the medical device and discharged from the fluid line system, wherein at least one temperature is measured in at least one temperature measuring section in the fluid line system, a temperature-dependent and time-dependent mortality rate of pathogens potentially present in the at least one temperature measuring section is calculated using the temperature, and the temperature is determined when the mortality rate reaches or exceeds a threshold value. The present disclosure also relates to a medical device, which is configured to be able to implement the method according to the present disclosure. Background Art

[0002] This type of method is disclosed, for example, in WO 2022 / 008889 A1. According to the document, the dialysis machine has a main body, a water purification system independent of the main body, and a liquid disinfection device arranged in the main body. A heating element and a temperature sensor are provided in the liquid disinfection device. The dialysis machine is disinfected by heating a certain volume of liquid by the heating element until a threshold value is exceeded and the volume of the heated liquid is guided through a first liquid circuit including the main body and the liquid disinfection device and through a second liquid circuit including the water purification system. During disinfection, the temperature of the heated liquid is monitored by means of a temperature sensor and is kept above the threshold value by means of a heating element. In order to be able to determine the completion of disinfection, the mortality value of the pathogens potentially present in the liquid circuit is calculated for the first and second liquid circuits based on the measured temperature.

[0003] The problem with traditional disinfection methods is that the calculation of mortality values ​​is inaccurate, so the duration of disinfection must be set longer than necessary to meet the required minimum safety. Summary of the invention

[0004] It is therefore an object of the present disclosure to provide a method or a medical device which enables a time-efficient implementation of the sterilization of the medical device.

[0005] This object is achieved with respect to the method by the features of claim 1 and with respect to the device by the features of claim 8. Advantageous developments are the subject matter of the dependent claims.

[0006] The method for disinfecting a medical device according to the present disclosure is particularly suitable for disinfecting a blood treatment device, preferably a dialysis machine, and comprises the following steps:

[0007] - heating the sterilizing fluid,

[0008] - introducing a sterilizing fluid into the fluid line system of a medical device,

[0009] - guide the sterile fluid out of the fluid piping system,

[0010] - measuring at least one temperature in at least one temperature measuring section in the fluid line system,

[0011] - calculating a temperature-dependent and time-dependent first mortality rate of germs potentially present in the at least one temperature measurement section using the temperature measured in the at least one temperature measurement section,

[0012] - determining a first threshold value for said first mortality rate, and

[0013] - determining when said first mortality rate reaches or exceeds said first threshold.

[0014] The disinfecting fluid may be, in particular, water with added citric acid or glycolic acid.

[0015] In particular, the fluid line system can comprise at least a part of a dialysate circuit, a blood circuit and / or a water purification circuit or can consist of at least one of these circuits.

[0016] The method according to the present disclosure further comprises the following steps:

[0017] - calculating a location-dependent temperature profile for a fluid line system, by means of which a calculated temperature can be assigned to at least one predetermined volume in the fluid line system,

[0018] - calculating at least one temperature-dependent and time-dependent second mortality rate of germs potentially present in the at least one predetermined volume using the temperature assigned to the at least one predetermined volume,

[0019] - determining a second threshold value for said at least one second mortality rate,

[0020] - determining when said at least one second mortality rate reaches or exceeds said second threshold, and

[0021] - When the first mortality rate reaches or exceeds the first threshold value and / or the at least one second mortality rate reaches or exceeds the second threshold value and / or the average value of the first mortality rate and the at least one second mortality rate calculated by the control device (8) reaches or exceeds the third threshold value determined by the control device (8), the disinfection is terminated.

[0022] The calculation of the position-dependent temperature profile can be performed in particular by means of extrapolation from the measured temperatures. In particular, the temperature can be measured at a plurality of locations in the fluid line system and the temperature profile of the fluid system can be calculated by interpolation and / or extrapolation using a plurality of measured temperatures. The temperature profile can be position- and time-dependent in particular.

[0023] The calculation of the second mortality rate can be carried out, in particular, based on the same type of calculation or the same characteristic values ​​as the calculation of the first mortality rate.

[0024] The temperature can be measured in particular at an inlet, an outlet, a heating element and / or a heat exchanger of the fluid line system.

[0025] In particular, the threshold value for the first mortality rate may differ from the threshold value for the second mortality rate. Preferably, the threshold value for the first mortality rate may be higher than the threshold value for the second mortality rate, so that higher requirements are placed on the first mortality rate compared to the second mortality rate. The third threshold value may be determined in particular with respect to preferably motile germs.

[0026] The threshold value can be determined in particular according to the history of the device. If the device is used, for example, to treat people with chronic hepatitis, a higher threshold value can be set for the (first and / or second and / or average) mortality rate.

[0027] If the temperature profile is used for disinfection, it is advantageously possible to calculate more precise values ​​for the mortality rate at locations of the fluid line system where the temperature cannot be measured or can be measured only under difficult conditions.

[0028] According to one aspect of the disclosure, at least one predetermined volume may be determined, which corresponds to a section without a temperature sensor and which is fixed in position relative to the fluid line system.

[0029] If the at least one predetermined volume is stationary relative to the fluid line system, the disinfection with respect to locally growing microorganisms can advantageously be monitored at locations where no temperature sensors are arranged.

[0030] According to one aspect of the present disclosure, at least one predetermined volume may be determined, which volume may be movable relative to the fluid line system.

[0031] If at least one predetermined volume is provided which is movable relative to the fluid line system, the disinfection can advantageously be monitored with respect to microorganisms which are movable or circulating in the fluid line system.

[0032] According to one aspect of the present disclosure, a time-dependent change in the temperature measured in the temperature measurement section may be considered when calculating the first mortality rate. When the temperature is measured at multiple locations (of one temperature measurement section or multiple temperature measurement sections), the time-dependent change in the multiple measured temperatures may be considered when calculating the first mortality rate. In other words, the temperature change within a specific time interval may be considered when calculating the first mortality rate for a specific time interval.

[0033] According to one aspect of the present disclosure, the time-dependent changes in the temperature measured in the temperature measurement section can be taken into account when calculating the temperature variation curve associated with the position, so that the temperature variation curve as a basis for calculating at least one second mortality rate is related to the position and time. When the temperature is measured at multiple positions (of one temperature measurement section or multiple temperature measurement sections), the time-dependent changes in the multiple measured temperatures can be taken into account when calculating the temperature variation curve associated with the position. In other words, the temperature changes within a specific time interval can be taken into account when calculating the temperature variation curve associated with the position for a specific time interval.

[0034] The temporal resolution of the disinfection monitoring can be improved if the change in the measured temperature(s) is taken into account when calculating the first mortality rate and / or the location-dependent temperature profile.

[0035] According to one aspect of the present disclosure, the A0 value may be used according to ISO 15883 to calculate the (first and / or second and / or average) mortality rate.

[0036] If the A0 value is used in accordance with ISO 15883, the knowledge gained during the sterilization of surgical instruments can be used advantageously when monitoring the sterility of the fluid line system.

[0037] According to one aspect of the present disclosure, a linear course can be preset at least in sections for the temperature variation curve. Preferably, the entire temperature variation curve can have a linear course.

[0038] Monitoring of the disinfection can be simplified if a linear course is predefined.

[0039] The medical device according to the present disclosure is particularly suitable for treating blood and is preferably configured as a dialysis machine. The medical device has a fluid pipeline system, a disinfection device and a control device. The disinfection device is configured to be able to heat a disinfection fluid for the disinfection fluid pipeline system, to be able to introduce into the fluid pipeline system and to be able to be led out from the fluid system. The fluid pipeline system has at least one temperature measuring section with a temperature sensor, and the temperature sensor is configured to be able to measure the temperature in the temperature measuring section. The control device is configured to be able to implement the method according to the present disclosure.

[0040] According to one aspect of the present disclosure, a medical device may have a graphical user interface that is configured to enable selection of different boundary conditions and / or configurations of the medical device, and a control device may be configured to adapt the course of a temperature change curve based on selection of at least one boundary condition and / or configuration.

[0041] The user interface can be constructed in particular so that a determined air temperature or a determined air temperature range, a determined air pressure or a determined air pressure range and / or a determined air humidity or a determined air humidity range of the surrounding environment of the medical device can be input or selected as boundary conditions. Alternatively or additionally, the user interface can be constructed in particular so that the following state of the medical device can be selected as the configuration of the medical device, in which different components are installed on the device. For example, the user interface can be constructed so that the configuration of the dialysis machine can be selected, in which a kit for a first treatment, such as hemodialysis, is installed on the dialysis machine, and in other cases, the configuration of the dialysis machine can be selected, in which a kit for a second treatment, such as hemodialysis filtration, is installed on the dialysis machine. For different configurations of the device or for different treatments of the dialysis machine, the corresponding temperature change curve can be stored in the database of the device or the control device. The user interface can be a touch-sensitive screen in particular.

[0042] The monitoring of the disinfection can be improved if the device is designed in such a way that the temperature profile can be adapted to different boundary conditions and / or configurations by means of a user interface.

[0043] According to one aspect of the present disclosure, the medical device can have at least one heating device that can be controlled by a control device, preferably in a disinfection device, and the control device can be configured to be able to adapt the trend of the temperature change curve according to the operation of the heating device. In other words, the control device can be configured so that the control device has adapted the trend of the temperature change curve by means of instructions to the heating device. Then, the adaptation implemented by means of the instructions can be checked based on the temperature measured thereafter. In particular, a database can be stored in the device or the control device, in which the corresponding temperature change curves for different instructions to the heating device are stored. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The present invention will be described in more detail below with reference to the accompanying drawings using preferred embodiments.

[0045] Figure 1 A schematic diagram shows a medical device in the form of a dialysis machine according to a first embodiment in a state in which dialysis can be performed;

[0046] Figure 2 Show Figure 1 A schematic diagram of a dialysis machine shown in FIG. 1 in a state capable of being sterilized;

[0047] Figure 3 Shown in Figure 2 A schematic detailed view of the pipeline section marked in FIG. 1 ; and

[0048] Figure 4 Shown along Figure 3Graph of the temperature profile of a pipeline section shown in FIG.

[0049] Figure 5 A schematic diagram shows a medical device in the form of a dialysis machine according to a second embodiment in a state in which dialysis can be performed;

[0050] Figure 6 Show Figure 5 Schematic diagram of a dialysis machine shown in FIG. 1 in a state in which the dialysis fluid circuit can be disinfected;

[0051] Figure 7 Show Figure 5 Schematic diagram of a dialysis machine shown in FIG. 1 in a state in which the blood circuit can be sterilized;

[0052] Figure 8 Shows a line section with a mark of the dialysate circuit Figure 6 The corresponding view;

[0053] Fig. 9 Figure 1 shows the line sections with markings in the dialysate circuit and the blood circuit. Figure 7 the corresponding view; and

[0054] Fig.10 The dialysis machine according to the second embodiment is shown. Figure 8 The temperature variation curve of the pipeline section marked in Fig. 9 Graph of the temperature profile of the pipeline section marked in . DETAILED DESCRIPTION

[0055] Figure 1 A medical device 2 in the form of a dialysis machine is shown, which has a fluid line system 4 in the form of a blood circuit, a disinfection device 6 and a control device 8 .

[0056] The fluid line system 4 or the blood circuit has a fluid inlet 10 into which a fluid or blood can be introduced during treatment.

[0057] Downstream of the fluid inlet 10 , a first bellows chamber 12 is arranged in the fluid line system 4 , which first bellows chamber is provided with a first pressure sensor 14 in order to be able to measure the pressure of the fluid located in the first bellows chamber 12 .

[0058] Downstream of the first airbag chamber 12 , a fluid pump 16 is arranged in the fluid line system 4 in order to be able to convey the fluid in the fluid line system 4 .

[0059] Downstream of the fluid pump 16, a fluid supply line 18 is arranged in the fluid line system 4. During treatment, an anticoagulant, such as heparin, may be added via the fluid supply line 18 to the delivered fluid or blood.

[0060] Downstream of the fluid supply line 18 in the fluid line system 4 , a second bellows chamber 20 is arranged in the fluid line system 4 , which second bellows chamber is provided with a second pressure sensor 22 in order to be able to measure the pressure of the fluid located in the second bellows chamber 20 .

[0061] Downstream of the second airbag chamber 20, a fluid filter 24 is arranged in the fluid pipeline system 4. The fluid filter 24 has a fluid inlet 26, a fluid outlet 28, a dialysate inlet 30 and a dialysate outlet 32. The fluid inlet 26 and the fluid outlet 28 are connected to the (not shown) fluid chamber. The dialysate inlet 30 and the dialysate outlet 32 ​​are connected to the (not shown) dialysate chamber. The fluid chamber and the dialysate chamber are connected to each other via the (not shown) semipermeable membrane. During treatment, components such as toxins can be discharged from fluid or blood through the semipermeable membrane by diffusion and / or convection. Here, the discharged component enters the dialysate, and the dialysate is introduced into the dialysate chamber by the dialysate inlet 30 from the dialysate container 34 by means of a dialysate pump 36, and in the dialysate chamber, it is mixed with the components taken out from the fluid or blood and is introduced into the dialysate container 40 by means of a dialysate pump 38 from the dialysate outlet 32 ​​as a dialysate with the components taken out from the fluid or blood.

[0062] Downstream of the fluid outlet 28 of the fluid filter 24 , a temperature sensor 42 is arranged in the fluid line system 4 , by means of which the temperature of the fluid conveyed in the fluid line system 4 can be measured.

[0063] Downstream of the temperature sensor 42 , a third bellows chamber 44 is arranged in the fluid line system 4 , which is provided with a third pressure sensor 46 in order to be able to measure the pressure of the fluid located in the third bellows chamber 44 .

[0064] Downstream of the third airbag chamber 44 , an air detector 48 is arranged in the fluid line system 4 , by means of which air detector air in the fluid conveyed in the fluid line system 4 can be detected.

[0065] Arranged downstream of the air detector 48 is a fluid outlet 50 of the fluid line system 4 , from which fluid or blood processed during treatment can be discharged.

[0066] The disinfection device 6 has a tank 52, which is connected to an inlet line 54, through which a disinfection fluid can be introduced into the tank 52 by means of an inlet pump 56 arranged in or at the inlet line 54. In addition, the tank 52 is connected to a discharge line 58, through which the disinfection fluid can be discharged from the tank 52 by means of a discharge pump 60 arranged in or at the discharge line 58. In addition, a temperature sensor 62 is arranged in or at the discharge line 58 downstream of the discharge pump 60. A heating device 64 is provided in or at the tank 52, by means of which the disinfection fluid in the tank 52 can be heated or warmed.

[0067] During treatment, the inlet line 54 and the outlet line 58 of the disinfection device 6 are not connected to the fluid line system 4 .

[0068] Figure 2 The device according to the disclosure is shown in a state in which the fluid line system 4 can be sterilized by means of a sterilizing device 6 .

[0069] In order to be able to perform disinfection of the fluid line system 4 in the preparation stage of the treatment, the discharge line 58 of the disinfection device 6 is connected to the fluid inlet 10 of the fluid line system 4 by means of a first washing bridge 66, the inlet line 54 of the disinfection device 6 is connected to the fluid outlet 50 of the fluid line system 4 by means of a second washing bridge 68, and the dialysate inlet 30 of the fluid filter 24 is connected to the dialysate outlet 32 ​​of the fluid filter 24 by means of a third washing bridge 70.

[0070] Washing bridges 66, 68 and 70 can be designed as separate hoses or pipe pieces, which can be manually mounted on corresponding connections of the fluid line system 4 or disinfection device 6. Alternatively or additionally, the device can have multi-way valves on the connections 10, 30, 32 and 50 of the fluid line system 4.

[0071] The multi-way valves on the connectors 10 and 50 can be constructed so that, on the one hand, they connect the fluid inlet 10 of the fluid piping system 4 to the blood outlet of the person to be treated and the fluid outlet 50 of the fluid piping system 4 to the blood inlet of the person to be treated in the treatment position, and on the other hand, they connect the fluid inlet 10 of the fluid piping system 4 to the discharge line 58 of the disinfection device 6 and the fluid outlet 50 of the fluid piping system 4 to the inlet line 54 of the disinfection device 6 in the disinfection position.

[0072] The multi-way valves at the connections 30 and 32 can be designed so that, on the one hand, they connect the dialysate inlet 30 of the fluid filter 24 to the dialysate container 24 and the dialysate outlet 32 ​​of the fluid filter 24 to the dialysate container 40 in the treatment position and, on the other hand, they connect the dialysate inlet 30 of the fluid filter 24 to the dialysate outlet 32 ​​of the fluid filter 24 in the disinfection position.

[0073] If a multi-way valve is provided, the switching of the device from a treatment state, in which dialysis can be performed, to a disinfection state, in which disinfection can be performed, can be designed such that no manual refitting is required.

[0074] During disinfection, the disinfection fluid is heated in the tank 52 by means of the heating device 64 and conveyed into the fluid line system 4 by means of the discharge pump 60 via the wash bridge 66. In the fluid line system 4, the heated disinfection fluid flows through the first airbag chamber 12 before it is conveyed into the fluid filter 24 by means of the fluid pump 16 via the second airbag chamber 20. The wash bridge 70 ensures that the disinfection fluid leaves the fluid filter 24 only via the fluid outlet 28. From the fluid outlet 28, the disinfection fluid flows back into the tank 52 via the temperature sensor 42, the third airbag chamber 44 and the wash bridge 68, wherein the inlet pump 56 conveys the disinfection fluid into the tank 52. The heat introduced into the fluid line system 4 by the disinfection fluid kills germs potentially present in the fluid line system 4.

[0075] In order to be able to assess the sterility of the device 2 according to the disclosure, the mortality rate of the germs potentially located in the relevant line section of the device 2 is calculated using the A0 value concept according to ISO 15883.

[0076] Figure 3 Shown in Figure 2 Schematic detailed view of a line section marked with a dashed line in FIG. 2 , which line section extends from a temperature sensor 62 of the disinfection means 6 to a fluid outlet 50 of the fluid line system 4 in the sterile state of the device 2 .

[0077] The A0 value is a measure of mortality and is calculated according to ISO 15883 by the following formula:

[0078]

[0079] "z" is a z value, and its definition can be referred to, for example, ISO 11139. For the A0 value, "z=10°C" applies.

[0080] "T(t)" is the temperature of the sterilizing fluid in °C as a function of time "T".

[0081] "Δt" is the selected time interval in seconds.

[0082] In order to achieve a time-efficient disinfection, the A0 value of the entire line segment is not calculated overall only with the aid of the two temperatures measured by the temperature sensors 42 and 62. According to the present disclosure, rather, the line segment or the fluid line system 4 or the relevant part of the fluid line system 4 is first divided into k subsegments. For example, as in Figure 4 As shown in , the pipeline section is divided into k=10 subsections.

[0083] Those subsections of the pipeline section or fluid pipeline system 4 extending over the temperature sensors 42 and 62 are temperature measurement sections according to the present disclosure. To calculate the A0 value of the temperature measurement section, the temperature T7 measured by the temperature sensor 42 and the temperature T1 measured by the temperature sensor 62 can be used directly. The A0 values ​​of the temperature measurement sections correspond to the first mortality rate according to the present disclosure, respectively.

[0084] In order to be able to calculate the A0 value also in the line sections remote from the temperature sensors 62 and 42, the temperature profile is calculated with the aid of the measured temperatures T1 and T7. Figure 4 As shown in , a linear temperature trend is assumed. The temperature can be calculated from the position x in the pipeline segment and the time t using the following formula:

[0085]

[0086] According to the temperatures T2 to T6 and T8 to T10 calculated from the temperature, corresponding A0 values ​​can be calculated for the section away from the temperature measurement section. These A0 values ​​away from the temperature measurement section preset by the temperature sensors 42 and 62 all correspond to the second mortality rate according to the present disclosure. The volume in the section away from the temperature measurement section corresponds to the predetermined volume according to the present disclosure.

[0087] In order to obtain Figure 3 The A0 value of the entire pipeline section shown in can be calculated using the calculated temperature curve using the following formula to calculate the average A0 value:

[0088]

[0089] For Figure 4 The example shown in FIG. 1 applies to “k=10”.

[0090] Used in temperature measurement section, away from temperature measurement section Figure 3The A0 values ​​of the segments of the line segments shown in the figure and the average A0 value are calculated by a control device 8, which is connected to the actuators (fluid pump 16, dialysate pump 36, dialysate pump 38, inlet pump 56, outlet pump 60 and heating device 64) and sensors (pressure sensors 14, 22 and 46, temperature sensors 42 and 62 and air detector 48) of the device 2 in terms of signal technology.

[0091] In order to be able to determine a threshold value for the A0 value, the device 2 has a touch-sensitive screen 72 which is connected to the control means 8 for signaling purposes.

[0092] At least one threshold value of the A0 value of the temperature measurement section, at least one threshold value of the subsection away from the temperature measurement section, and at least one threshold value of the average A0 value of the pipeline section can be input on the screen 72. The control device 8 determines the corresponding threshold value according to the input on the screen 72.

[0093] During the disinfection, the control unit 8 continuously compares the calculated A0 value for the temperature measurement section and the subsection exceeding the temperature measurement section and the calculated average A0 value with the corresponding pre-determined threshold value. Once the calculated A0 value for the temperature measurement section and the subsection exceeding the temperature measurement section and the calculated average A0 value at a certain point in time reach or exceed the corresponding threshold value, the pumps 60, 16 and 56 are stopped by the control device, and the control device 8 ends the disinfection.

[0094] Figure 5 A medical device 102 is shown in the form of a dialysis machine having a fluid line system 104 in the form of a blood circuit, a fluid line system 105 in the form of a dialysate circuit, disinfection means 106 and control means 108 , as used during a treatment.

[0095] The fluid line system 104 or the blood circuit can be part of a dialysis machine or a reusable and individually installable set consisting of blood hoses and a dialyzer.

[0096] The fluid line system 104 or the blood circuit has a fluid inlet 110 into which a fluid or blood can be introduced during treatment.

[0097] Downstream of the fluid inlet 110 , various functional components are arranged in the fluid line system 104 , which functional components are not essential to the present disclosure. These are grouped together as component 111 .

[0098] A pump 116 is arranged downstream of 111 , which pump conveys the liquid in the fluid line system 104 .

[0099] Downstream of the pump 116, a fluid filter 124 is arranged in the fluid line system 104. The fluid filter 124 has four connectors for fluids. Two connectors are responsible for the introduction (126) and the export (128) of the blood circuit and two connectors are responsible for the introduction (130) and the export (132) of the dialysate circuit. The blood and dialysate circuits are connected to each other through a semipermeable membrane (not shown). During treatment, components such as toxins can be discharged from the fluid or blood through the semipermeable membrane by diffusion and / or convection. Here, the discharged components reach the dialysate from the blood circuit.

[0100] Downstream of the fluid outlet 128 of the fluid filter 124 , a temperature sensor 142 is arranged in the fluid line system 104 , by means of which the temperature of the fluid conveyed in the fluid line system 104 can be measured.

[0101] Downstream of the temperature sensor 142 , various functional components are arranged in the fluid line system 104 , which functional components are not essential to the present disclosure. These are grouped together as component 143 .

[0102] Arranged downstream of the component 143 is a fluid outlet 150 of the fluid line system 104 , from which fluid or blood processed during treatment can be discharged.

[0103] The fluid line system 105 or the dialysate circuit has a fluid inlet 174 , into which water can be introduced.

[0104] A fluid tank 152 is arranged downstream of the fluid inlet 174 , in which fluid or dialysate during treatment is collected.

[0105] The pump 176 can take fluid from the fluid tank 152 and deliver the fluid to the heater 178 in a heating loop. The heater 178 is used to heat the liquid and deliver it back to the fluid tank 152 via a pipe 180.

[0106] Contained in the line 180 , which can be designed, for example, as a hose element W6 , is a temperature sensor 182 which determines the temperature of the fluid in the dialysing fluid circuit 105 after initial heating.

[0107] The pump 184 can take fluid from the fluid tank 152 and convey it in the direction of the blood circuit 104. Different functional components of the dialysate circuit are arranged downstream of the pump 184, which are not essential for the present disclosure except for the temperature sensor 188. These components are combined with 186 and 190. The temperature sensor 188 serves to determine the temperature of the fluid conveyed in the direction of the blood circuit 104.

[0108] Downstream of the component 190, the liquid is conducted via a line 192, which can be designed as a hose, to the fluid filter 124. In this case, the line 192 can be connected to the fluid connection 130 on the fluid filter 124 via a coupling.

[0109] Downstream of the fluid filter 124, the liquid can be conducted away from the fluid filter 124 via a line 196, which can be designed as a hose. In this case, the line 194 can be connected to the fluid filter 124 via a coupling.

[0110] Downstream of line 194 , the liquid is directed through various components which are not essential to the present disclosure. These components are grouped together as 196 .

[0111] A pump 198 is arranged downstream of the component 196, which pump pushes the liquid back into the fluid tank 152. The fluid tank 152 is designed in this case such that the discharged liquid does not have to come into contact with the introduced liquid.

[0112] The valve 200 is arranged downstream of the pump 198. In therapeutic operation, the valve 200 conducts the fluid further in the direction of the outlet 202.

[0113] The disinfection device 106 has an inlet or an inlet 204, through which a disinfectant can be introduced. The disinfection device 106 does not necessarily have to be connected during treatment operation.

[0114] Figure 6 The medical device 102 is shown during disinfection of the dialysate circuit 105 .

[0115] For disinfection purposes it is necessary to distinguish between different phases.

[0116] The introduction of disinfectant is carried out in the first stage of disinfection.

[0117] For disinfection, a disinfectant is introduced via the inlet 204. For this purpose, the lines 192 and 194 are connected to the disinfection device 106 by means of their couplings. The three-way valve 206 of the disinfection device 106 can be operated in various configurations. During the introduction of the disinfectant, the disinfectant connects the inlet 204 to the line 194. The pump 198 can thus introduce the disinfectant into the circuit 105. Downstream of the pump 198, the valve 200 is set so that the disinfectant enters the fluid tank 152. There, the valve mixes with the water from the fluid inlet 174. This mixture is referred to below as disinfectant liquid.

[0118] In the second stage of the disinfection, the disinfection liquid is heated. For this purpose, the liquid is output from the fluid tank 152 by means of a pump 176 via a heating element of a heater 178. The temperature of the disinfection liquid is continuously determined via a temperature sensor 182.

[0119] Here, the liquid may be continuously and repeatedly circulated over the heating element of heater 178 in order to reach the desired temperature.

[0120] In the third phase of disinfection, heated disinfection liquid circulates in the dialysate circuit 105. The actual disinfection of the dialysate circuit 105 takes place here.

[0121] For this purpose, the same actuators as in the treatment phase can be used to distribute the liquid in the dialysate circuit 105. The pump 184 delivers the disinfection liquid from the fluid tank 152 via the component(s) 186, the temperature sensor 188 and the component(s) 190. The temperature sensor 188 allows the temperature of the disinfection liquid to be measured. This measured value is used to extrapolate the temperature in other areas of the dialysate circuit 105.

[0122] Downstream of component(s) 190, the liquid is further delivered to the disinfection device 106. During this phase, the three-way valve 206 is set to direct the fluid further into the line 194. The liquid is directed back into the fluid tank 152 via component(s) 196, pump 198 and valve 200.

[0123] In this case, the temperature of the disinfecting liquid decreases continuously during the flow path, so that the disinfecting effect decreases further all the time.

[0124] The heating circuit having elements 176-182 remains activated during this phase to maintain the temperature in fluid tank 152. The disinfecting liquid may be circulated through the fluid system during this phase until the desired mortality value is reached at any location.

[0125] Figure 7 The medical device 102 is shown during sterilization of a blood circuit 104 .

[0126] In the (optional) fourth stage of disinfection, in addition to the dialysate side, the blood circuit 104 can be additionally disinfected. The circulation of the disinfection liquid from the disinfection stage 3 is continued here. However, in this stage, the couplings of the lines 192 and 194 are connected to the fluid filter 124 again.

[0127] The fluid filter 124 can thus be flushed with the heated disinfectant liquid. The disinfectant can also enter the blood circuit 104 through the semipermeable membrane.

[0128] In this phase, the fluid inlet 110 and the fluid outlet 150 of the blood circuit 104 are connected to one another by means of the coupling 208 .

[0129] The pump 116 is used in this phase to circulate the liquid in the blood circuit 104. The temperature in the blood circuit 124 is continuously increased by the substances and heat exchange in the fluid filter 124. The temperature sensor 142 measures the temperature in the blood circuit 104 and can be used to extrapolate the temperature in other areas of the blood circuit 104.

[0130] In order to be able to assess the sterility of the device 102 according to the present disclosure, the mortality rate of the germs potentially located in the relevant line section of the device 102 is calculated using the A0 value concept according to ISO 15883.

[0131] Figure 8 Shown with Figure 6 A corresponding illustration with labeled line sections of the dialysate circuit 105 during the disinfection of the dialysate circuit 105 . Fig. 9 Shown with Figure 7 A corresponding illustration with marked line sections in the dialysate circuit 105 and in the blood circuit 104 during additional disinfection of the blood circuit 104 .

[0132] Fig.10 The dialysate circuit 105 and the blood circuit 104 are shown in FIG. Figure 8 and Fig. 9 Schematic detailed view of the temperature profile in the line sections marked in . Here, the temperature profile of the line section in the dialysate circuit 105 is shown with a solid line and the temperature profile of the line section in the blood circuit 104 is shown with a dashed line. The highest temperature is reached in the heating element of the heater 178 and from there it decreases further in the profile of the fluid path x. The temperatures are measured at the locations of the temperature sensors 182 and 188. The temperatures in other areas of the dialysate circuit 105 can be extrapolated using these measured values.

[0133] The temperature profile in the blood circuit 104 is derived from the temperature profile in the dialysate circuit. In the region of the fluid filter 124, the temperatures in the dialysate circuit 105 and the blood circuit 104 are almost identical, since the fluid filter 124 is a very effective heat exchanger due to its semipermeable membrane. Furthermore, the temperature in the blood circuit 104 is known for the location or section of the temperature sensor 142. The temperature in the remaining region of the blood circuit 104 can be extrapolated via these two points, i.e., the fluid filter 124 and the temperature sensor 142.

[0134] As in the first embodiment, the A0 value is used as a measure of mortality and is calculated according to ISO 15883 by the following formula:

[0135]

[0136] "z" is a z value, and its definition can be referred to, for example, ISO 11139. For the A0 value, "z=10°C" applies.

[0137] "T(t)" is the temperature of the sterilizing fluid in °C as a function of time "T".

[0138] "Δt" is the selected time interval in seconds.

[0139] In order to achieve a time-efficient disinfection, the A0 value is not calculated for the entire line section as a whole but only with the aid of the temperatures T1, T3 and T6.2 measured by the temperature sensors 182, 188 and 142. According to the disclosure, more precisely, the line section of the dialysate circuit 105 to be disinfected (see Figure 8 and Fig.10 The solid line in ( ) is first divided into k sub-segments. For example, Fig.10 As shown in , the line section is divided into k=10 subsections. If the blood circuit is disinfected, the line section of the dialysate circuit 105 from the temperature sensor 182 to the fluid filter 124 and then the line section of the blood circuit 104 are viewed together and divided into k subsections (see Fig. 9 and in Fig.10 Solid line to x(124) and dashed line from x(124)).

[0140] Those subsections of the pipeline sections or fluid pipeline systems 104 and 105 extending over the temperature sensors 142, 182 and 188 are temperature measurement sections according to the present disclosure. To calculate the A0 values ​​of the temperature measurement sections, the temperatures measured by the temperature sensors 142, 182 and 188 (e.g., T1=T(182), T3=T(188) and T6.2=T(142)) can be used directly. The A0 values ​​of the temperature measurement sections correspond to the first mortality rates according to the present disclosure, respectively.

[0141] In order to be able to calculate the A0 value also in line sections remote from the temperature sensors 142, 182 and 188, the temperature profiles for the dialysate circuit 105 and for the blood circuit 104 are calculated from the measured temperatures T1=T(182), T3=T(188) and T6.2=T(142). Fig.10 As shown in , a linear temperature trend is assumed. The temperature can be calculated from the position x in the pipeline segment and the time t using the following formula:

[0142]

[0143] The corresponding A0 values ​​can be calculated for the sections away from the temperature measurement section by means of the temperatures T2, T4, T5 and T6.1 to T10.1 or T2, T4, T5 and T6.2 to T10.2 calculated by the formula. These A0 values ​​away from the temperature measurement sections preset by the temperature sensors 142, 182 and 188 all correspond to the second mortality rate according to the present disclosure. The volume in the section away from the temperature measurement section corresponds to the predetermined volume according to the present disclosure.

[0144] In order to obtain Figure 8 or Fig. 9 The A0 value of the entire pipeline section shown in can be calculated using the calculated temperature curve using the following formula to calculate the average A0 value:

[0145]

[0146] For Fig.10 The example shown in FIG. 1 applies to “k=10”.

[0147] Used in temperature measurement section, away from temperature measurement section Figure 8 and Fig. 9 The segmental A0 values ​​and the average A0 value of the line segment shown in are calculated by control means 108 which is connected in terms of signals to actuators (eg pumps 176 , 184 , 198 and 116 ) and sensors (eg temperature sensors 142 , 182 and 188 ) of device 102 .

[0148] In order to be able to determine a threshold value for the A0 value, device 102 has a touch-sensitive screen 172 which is connected to control means 108 for signaling purposes.

[0149] At least one threshold value of the A0 value of the temperature measurement section, at least one threshold value of the subsection away from the temperature measurement section, and at least one threshold value of the average A0 value of the pipeline section can be input on screen 172. The control device 108 determines the corresponding threshold value according to the input on screen 172.

[0150] During disinfection, the control unit 108 continuously compares the calculated A0 values ​​for the temperature measurement segment and the sub-segment beyond the temperature measurement segment and the calculated average A0 value with the corresponding pre-determined threshold values. Once at a point in time, the calculated A0 values ​​for the temperature measurement segment and the sub-segment away from the temperature measurement segment and the calculated average A0 value reach or exceed the corresponding threshold value, the control device 108 ends the disinfection by starting to flush the disinfectant (for example, by means of pumps 176, 184, 198 and 116) and turning off the heater 178.

[0151] Reference numerals list

[0152] 2;102 devices

[0153] 4; 104, 105 fluid piping system

[0154] 6; 106 disinfection devices

[0155] 8; 108 control devices

[0156] 10; 110 Fluid inlet of fluid piping system

[0157] 12 First airbag chamber

[0158] 14. First pressure sensor

[0159] 16;116 Fluid pump

[0160] 18 Fluid supply line

[0161] 20 Second airbag chamber

[0162] 22 Second pressure sensor

[0163] 24;124 Fluid filter

[0164] 26; 126 Fluid inlet of fluid filter

[0165] 28; 128 Fluid outlet of fluid filter

[0166] 30;130 dialysate inlet

[0167] 32;132 Dialysate outlet

[0168] 34 Dialysis fluid container

[0169] 36 Dialysis fluid pump

[0170] 38 Dialysate Pump

[0171] 40 dialysate container

[0172] 42;124 Temperature sensor in fluid piping system

[0173] 44 Third airbag chamber

[0174] 46 Third pressure sensor

[0175] 48 Air Detector

[0176] 50; 150 Fluid outlet of fluid piping system

[0177] 52; 152 boxes

[0178] 54 Enter the pipeline

[0179] 56 Enter the pump

[0180] 58 Discharge line

[0181] 60 Discharge pump

[0182] 62 Temperature sensor in disinfection device

[0183] 64 Heating device

[0184] 66 First Washing Bridge

[0185] 68 Second Washing Bridge

[0186] 70 Third Washing Bridge

[0187] 72; 172 Touch-sensitive screen

[0188] 111 Parts

[0189] 143 Parts

[0190] 174 Fluid inlet

[0191] 176 Pump

[0192] 178 Heater

[0193] 180 Pipeline

[0194] 182 Temperature Sensor

[0195] 184 Pumps

[0196] 186; 190 parts

[0197] 188 Temperature Sensor

[0198] 192, 194 pipeline

[0199] 196 Parts

[0200] 198 Pumps

[0201] 200 valve

[0202] 202 Exit

[0203] 204 Entrance

[0204] 206 Three-way valve

[0205] 208 coupling portion.

Claims

1. A method for disinfecting a medical device (2; 102), in particular a blood treatment device, preferably a dialysis machine, comprising the steps - heating the sterilizing fluid, - introducing the sterilizing fluid into the fluid line system (4; 104, 105) of the medical device (2; 102), - directing the disinfection fluid out of the fluid line system (4; 104, 105), - measuring at least one temperature (T7; T1, T3, T6.2) in at least one temperature measuring section within the fluid line system (4; 104, 105), - calculating a temperature-dependent and time-dependent first mortality rate of pathogens potentially present in the at least one temperature measurement section using the temperatures (T7; T1, T3, T6.2) measured in the at least one temperature measurement section, - determining a first threshold value for said first mortality rate, and - determining when said first mortality rate reaches or exceeds said first threshold, Features step: - calculating a position-dependent temperature profile of the fluid line system (4; 104, 105), by means of which at least one predetermined volume in the fluid line system (4; 104, 105) can be assigned a calculated temperature (T2, T3, T4, T5, T6, T8, T9, T10; T2, T4, T5, T6.1-T10.1, T7.2-T10.2), - calculating at least one temperature-dependent and time-dependent second mortality rate of germs potentially present in the at least one predetermined volume using the temperatures (T2, T3, T4, T5, T6, T8, T9, T10; T2, T4, T5, T6.1-T10.1, T7.2-T10.2) assigned to the at least one predetermined volume, - determining a second threshold value for said at least one second mortality rate, - determining when said at least one second mortality rate reaches or exceeds said second threshold, and - When the first mortality rate reaches or exceeds the first threshold value and / or the at least one second mortality rate reaches or exceeds the second threshold value and / or the average value of the first mortality rate and the at least one second mortality rate calculated by the control device (8; 108) reaches or exceeds the third threshold value determined by the control device (8; 108), the disinfection is terminated.

2. The method according to claim 1, wherein: At least one predetermined volume is determined, which corresponds to a section of the fluid line system (4; 104, 105) which is stationary and free of temperature sensors.

3. The method according to claim 1 or 2, wherein: At least one predetermined volume is determined, which volume is movable relative to the fluid line system.

4. The method according to any one of claims 1 to 3, wherein: The time-dependent change in the temperature ( T7 ; T1 , T3 , T6 , 2 ) measured in the temperature measurement section is taken into account when calculating the first mortality rate.

5. The method according to any one of claims 1 to 4, wherein: When calculating the location-dependent temperature profile, the time-dependent change in the temperature (T7; T1, T3, T6.2) measured in the temperature measurement section is taken into account, so that the temperature profile on which the at least one second mortality rate is based is location- and time-dependent.

6. The method according to any one of claims 1 to 5, wherein: The A0 value according to ISO 15883 was used to calculate the mortality rate.

7. The method according to any one of claims 1 to 6, wherein: A linear course is provided at least in sections for the temperature profile.

8. A medical device (2; 102), in particular for treating blood, preferably in the form of a dialysis machine, having Fluid piping system (4; 104, 105), a disinfection device (6; 106) which is configured to heat a disinfection fluid, to introduce the disinfection fluid into the fluid line system (4; 104, 105) and to discharge the disinfection fluid from the fluid line system (4; 104, 105), and A control device (8; 108), wherein The fluid pipeline system (4; 104, 105) has at least one temperature measuring section, the temperature measuring section has a temperature sensor (42; 142, 182, 188), the temperature sensor is configured to be able to measure the temperature (T7; T1, T3, T6.2) in the temperature measuring section, and The control device (8; 108) is designed to be able to carry out the method according to any one of claims 1 to 7.

9. The medical device (2; 102) according to claim 8, wherein The medical device (2; 102) has a graphical user interface (72; 172) which is designed to enable selection of different boundary conditions and / or configurations of the medical device (2; 102), and The control device (8; 108) is designed to be able to adapt the course of the temperature profile as a function of the selection of at least one boundary condition and / or configuration.

10. The medical device (2; 102) according to claim 8 or 9, wherein: The medical device (2; 102) has at least one heating device (64; 178) controllable by the control device (8; 108), and The control device (8; 108) is designed to be able to adapt the course of the temperature profile as a function of the operation of the heating device (64; 178).

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