PERITONEAL DIALYSIS DEVICE

Description

[0001] The invention relates to a device for performing automated peritoneal dialysis treatment on a patient.

[0002] Peritoneal dialysis (PD) is also known as peritoneal dialysis. There are various PD methods, including automated peritoneal dialysis (APD), which uses peritoneal dialysis machines. In APD, all or at least some of the treatment steps are automated. These can include, for example, switching pumps on or off, opening or closing valves, etc.

[0003] Creating a flow of dialysis solution can be done gravimetrically, i.e., by gravity, and / or by means of one or more pumps.

[0004] The present invention is not limited to any particular type of PD, i.e. it includes automatic, non-automatic, gravimetric and pump-operated devices.

[0005] During peritoneal dialysis (PD), the machine introduces a dialysis solution into the patient's abdominal cavity via a catheter during an inflow phase. This step, as well as the drainage from the abdominal cavity, can be performed gravimetrically. The dialysis solution is then held in the abdominal cavity for a retention period. During this time, small molecules from the blood can pass into the dialysis solution via the capillaries of the peritoneum due to a concentration gradient. Furthermore, water can also be removed from the body in this way, provided the dialysis solution has a higher concentration of osmotically active substances than the blood. After the retention period, the machine removes the dialysis solution, enriched with excreted substances and thus used up, from the abdominal cavity via the catheter in a drainage phase. Fluid exchange can be performed gravimetrically or actively using a pump.

[0006] The cycle of inflow phase, retention phase, and outflow phase is repeated several times in typical procedures, for example, at night while the patient sleeps. A new inflow phase is always started when the machine detects that the outflow phase is complete, i.e., that the used dialysis fluid has completely drained from the patient's abdominal cavity.

[0007] It is known in the prior art to provide an estimate of the total treatment duration of peritoneal dialysis treatment, encompassing several cycles, in the interest of improved planning reliability for caregivers and patients. For example, DE 10 2014 005 122 A1 discloses how to estimate the total treatment duration by taking the ideal treatment duration as a starting point and increasing it in a specific way. Among other things, delay factors are provided for the inflow and outflow times of dialysis fluid to and from the patient, which are intended to reflect less-than-ideal catheter behavior (for example, a factor or multiplier of 1.5). However, to date, such delay factors have only been estimated or set non-patient-specifically, which, while improving the estimation of the total treatment duration, has still resulted in considerable uncertainties.Any ongoing deterioration of catheter quality due to fibrin buildup or a change in the catheter's position within the patient (within the abdominal cavity or Douglas space) has not been taken into account so far.

[0008] The object of the invention is to provide a peritoneal dialysis device with which a more reliable estimate of the total treatment duration can be made.

[0009] Against this background, the invention relates to a peritoneal dialysis device for performing automated peritoneal dialysis treatment with repeating cycles, the cycles comprising an inflow phase, a holding period, and an outflow phase for the dialysis fluid, wherein the device has a control unit and a measuring device for determining the inflow and / or outflow behavior of the dialysis fluid from a patient. According to the invention, the control unit is configured to determine a delay factor based on the measured values ​​collected over several inflow and / or outflow phases, which relates a theoretical inflow and / or outflow duration to the actual inflow and / or outflow duration of dialysis fluid to and from the patient.

[0010] The invention therefore aims at determining a patient-specific delay factor. This delay factor can be determined, for example, based on a plurality of measured values ​​or value trends (curves) that were measured in a specific number of previous cycles or treatments. It can thus be a patient-specific average value.

[0011] In one embodiment, the device is a gravimetric device. For example, one or more valves may be provided, and the control unit may be configured such that the valve(s) are opened after the holding phase and before the start of the drainage phase to allow gravimetric drainage of dialysis fluid from the patient, and / or that the valve(s) are opened after the drainage phase and before the start of the inflow phase to allow gravimetric inflow of dialysis fluid to the patient.

[0012] In one embodiment, the device includes a dialysis pump designed to pump dialysis fluid to and / or from the patient. It can therefore be an actively pumping device in which the control unit is configured to withdraw dialysis fluid from the patient during the outflow phase and / or supply it to the patient during the inflow phase.

[0013] In one embodiment, the measuring device is configured to determine the flow rate of the dialysis fluid. A flow sensor can be provided, which allows the temporal profile of the flow rate during the inflow and / or outflow phase to be determined and recorded in the control unit. In this embodiment, the control unit can be configured to determine the delay factor based on the flow rate measurements collected over several inflow or outflow phases. The temporal profile of the flow rate, or the flow rate itself, can also be determined gravimetrically by weighing the solution, a bag, or another container using a scale at two different times. The flow rate can then be inferred or calculated from this measurement.

[0014] In one embodiment, the measuring device is designed to determine the hydrostatic pressure in the line or the pressure differential at a dialysis pump. A pressure sensor can therefore be provided, which allows the hydrostatic pressure profile in the line, particularly in gravimetric systems, or the pressure drop at a dialysis pump, in active systems (i.e., systems with at least one pump), to be determined and recorded in the control unit during the inlet and / or outlet phase. InIn this embodiment, the control unit can be configured to determine the delay factor based on pressure or pressure differential measurements collected over several inlet and outlet phases. The pressure differentials can be recorded in the control unit as functions of time or as functions of the fill volume. In this respect, the device can include a measuring device for both flow rate and pressure or pressure differential, and the delay factor can be determined based on both of these measurements.

[0015] InIn one embodiment, the control unit is configured to output an estimate of the total treatment time for a given prescription. This estimate is generated by multiplying a theoretical start-up and / or run-down time by a delay factor. For example, determining the ideal total treatment time may involve multiplying an ideal cycle time by the number of cycles. Similarly, determining the actual total treatment time involves multiplying an actual cycle time by the number of cycles. The ideal cycle time is determined by summing the idealized duration of the start-up phase, the idealized duration of the holding phase, and the idealized duration of the run-down phase. Similarly, the actual cycle time is determined by summing the actual duration of the start-up phase, the actual duration of the holding phase, and the actual duration of the run-down phase.According to the invention, the actual duration of the warm-up phase can now be obtained by multiplying the idealized duration of the warm-up phase by the delay factor. Similarly, according to the invention, the actual duration of the cool-down phase can be obtained by multiplying the idealized duration of the cool-down phase by the delay factor.

[0016] In one embodiment, the control unit is designed to output a signal when the delay factor exceeds a threshold. For this purpose, the device may include a signaling unit or an interface for communication with an external signaling unit. Suitable signals include, for example, optical signals, audio signals, or vibration signals. Based on a signal output, a decision can be made, for example, as to whether it might be advisable to change the prescription given the circumstances. Furthermore, a decision can be made, for example, as to whether it might be advisable to replace the catheter. This enables evaluation based on graphical or tabular records in suitable software.

[0017] In one embodiment, the control unit is designed to modify a treatment parameter when the delay factor exceeds a certain threshold. This allows for better adaptation of treatment parameters to the prevailing real-world conditions by using the delay factor.

[0018] In one embodiment, the modified treatment parameter is a criterion for determining the end of a discharge phase, preferably a minimum discharge rate. The control unit can be configured to determine whether a discharge phase has ended and a new inlet phase can begin, based on preset criteria, such as a minimum discharge volume reached and / or a flow rate falling below a certain threshold.

[0019] In one embodiment, the modified treatment parameter is the pump rate of a dialysis pump designed to pump dialysis fluid to and / or from the patient. It may be provided that an initial value for the pump rate is modified, for example, the pump rate set at the beginning of a treatment phase. Furthermore, it may be provided that a profile of the pump rate is modified, for example, the change in the initial pump rate during a treatment phase.

[0020] Furthermore, at least one memory can be provided in which the delay factor is stored in the treatment protocol to enable further processing, preferably a graphical representation of the delay factor across multiple treatments. The memory can be an integral part of the device or implemented as external memory.

[0021] Furthermore, the invention comprises a method for performing peritoneal dialysis using a peritoneal dialysis device according to the invention, wherein a delay factor is determined based on the measured values ​​collected over several inflow and / or outflow phases, which relates a theoretical inflow and / or outflow duration to the actual inflow and / or outflow duration of dialysis fluid to and from the patient. Advantageous embodiments of the method will become apparent from the above description of the design of the control unit in the peritoneal dialysis device according to the invention.

[0022] Further details and advantages of the invention will become apparent from the exemplary embodiment explained below with reference to the figures. The figures show: Figure 1: a possible course of catheter quality over several treatments; Figure 2: another possible course of catheter quality over several treatments; and Figure 3: possible temporal courses of the outflow rate (volume / time) of dialysis fluid from the abdominal cavity during the outflow phase. According to the exemplary embodiment, a peritoneal dialysis machine is provided, which is designed for carrying out automated peritoneal dialysis treatment with repeating cycles comprising an inlet phase, a holding period, and an outlet phase for the dialysis fluid. The machine includes a control unit, a measuring device for determining the inflow and outflow rate of the dialysis fluid from a patient and a dialysate pump for conveying dialysis fluid to and from the patient.

[0023] The control unit contains an algorithm that determines the actual total treatment time (Δt total, real). The algorithm is based on multiplying the actual cycle time (Δt cycle, real) by the number of cycles (n), supplemented by the actual duration of an initial run-out phase (Δt init, real) and the actual duration of a final run-in phase (Δt fin, real). Δt Gesamt , real = Δt Zyklus , real × n + Δt Init , real + Δt Fin , real

[0024] The real cycle duration (Δt cycle,real ) is determined from the sum of the real run-in duration (Δt in,real ), the real holding duration (Δt hold,real ) and the real run-out duration (Δt out,real ). Δt Zyklus , real = Δt Ein , real + Δt Halte , real + Δt Ab , real

[0025] The present invention relates to the precise determination of the actual run-in time (Δtin,real), the actual run-out time (Δtab,real), the actual duration of the initial run-out phase (Δtinit,real), and the actual duration of the final run-in phase (Δtfin,real). According to the invention, the duration of these actual phases is calculated by multiplying the corresponding ideal durations (Δtin,ideal, Δtab,ideal, Δtinit,ideal, and Δtfin,ideal), which can be calculated for a known device configuration, by a delay factor F. Different delay factors are provided for the run-in processes (Δtin, Δtfin) and the run-out processes (Δtab, Δtinit), namely the factors Fab and Fin. Δt Ein , real = Δt Ein , ideal × F Ein Δt Ab , real = Δt Ab , ideal × F Ab Δt Init , real = Δt Init , ideal × F Ab Δt Fin , real = Δt Fin , ideal × F Ein

[0026] The delay factors FAb and FEin are determined by the control unit based on a multiple of measured trends in the drainage and inflow rates, respectively, which were measured over a specific number of previous cycles (for example, 20 cycles). This is therefore a patient-specific average value that is representative of catheter quality.

[0027] In Figure 1 and 2 Possible trends in catheter performance over the course of several treatments are depicted. The abscissa represents the sequential number of a cycle consisting of the insertion phase, the holding phase, and the drainage phase. The ordinate represents a quantity representative of catheter performance, which can be determined, for example, by measuring the flow rate at a specific pressure differential. A value of 1 represents ideal catheter performance, while values ​​below 1 indicate correspondingly reduced catheter performance. In the Figure 1After a certain number of cycles, a sudden, significant drop in catheter performance is observed, which may be caused, for example, by a sudden change in the catheter's position within the patient's abdominal cavity. Figure 2 A gradual decline in catheter performance is illustrated, as can be observed, for example, through a continuous clogging of the catheter with fibrin.

[0028] In the device according to the exemplary embodiment, the control unit is further configured to output a signal when a delay factor FAb or FEin exceeds a threshold value stored in the control unit. For this purpose, the device includes an interface for communication with an external computer. Based on a signal output, a decision can be made, for example, as to whether it might be advisable to change the prescription given the circumstances. Furthermore, a decision can be made, for example, as to whether it might be advisable to exchange the catheter, check or correct its position, or, if necessary, flush the catheter. The evaluation is performed based on graphical and tabular records in suitable software.

[0029] The control unit is further designed such that the value used as a criterion for determining the end of a run-off phase for a discharge rate is corrected downwards by a certain amount at the end of the run-off phase if the delay factor F Ab exceeds the threshold value stored in the control unit. Figure 3This graph shows the flow rate over time in a periodontal dialysis machine. The "Reference" curve shows the flow rate over time under normal conditions. The flow rate initially stabilizes at approximately 200 ml / min and decreases from about minute 5 onwards due to the decreasing hydrostatic pressure. The "Disturbance" curve shows the flow rate over time when catheter performance is impaired. The flow rate initially stabilizes at only about 150 ml / min. Here, too, a decrease is observed after about minute 5, so that after about 10 minutes significantly less fluid has drained. Without appropriate countermeasures, this would result in poorer treatment quality and longer treatment duration. Correcting the threshold value counteracts this problem.

[0030] Furthermore, the initial value and the rate change profile of the dialysis pump are also modified during the warm-up or cool-down phase if the delay factor FAb or FEin exceeds the threshold value stored in the control unit. This further counteracts the problem of declining treatment quality.

[0031] Advantages of the solution according to the invention include, for example, the possibility of a more reliable estimation of the total treatment duration of a peritoneal dialysis treatment for a given prescription. Furthermore, the invention makes it possible to monitor the quality of the catheter over the course of several treatments and also, for example, to visualize it graphically. Early detection of changes to the catheter is possible. In one embodiment of the invention, the treatment parameters and / or system parameters can be better adapted to an individual situation or to an individual patient. The need for a prescription correction can also be recognized with the help of the solution according to the invention in one embodiment. Changes in the patient's condition can be detected. Notifications and feedback to the patient regarding various behavioral patterns can be improved.

Claims

1. Peritoneal dialysis machine for carrying out a peritoneal dialysis treatment with recurring cycles, the cycles comprising an inflow phase, a dwell period and a drainage phase for the dialysis fluid, the machine having a control unit and a measurement apparatus for determining the inflow and / or drainage behavior of the dialysis fluid to and / or from a patient, characterized in that the control unit is configured to determine, on the basis of the measured values collected over a plurality of inflow phases and / or drainage phases, a time delay factor that relates a theoretical inflow and / or drainage duration to the actual inflow and / or drainage duration of the dialysis fluid to and / or from the patient, and in that the control unit is configured to modify a treatment parameter and / or a system parameter when the time delay factor exceeds a determined threshold value.

2. Peritoneal dialysis machine in accordance with claim 1, characterized in that the machine is a gravimetrically working machine.

3. Peritoneal dialysis machine in accordance with claim 1, characterized in that the machine has a dialysis pump that is configured to pump dialysis fluid from and / or to the patient.

4. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that the measurement apparatus is configured to determine the flow rate of the dialysis fluid.

5. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that the measurement apparatus is configured to determine a hydrostatic pressure in the line or a pressure difference at a dialysis pump of a peritoneal dialysis machine not working purely gravimetrically.

6. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that the control unit is configured to output an estimate of the total treatment duration for a specific prescription, with a theoretical and / or calculated inflow duration and / or drainage duration being multiplied by the time delay factor in establishing the estimate.

7. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that the control unit is configured to output a signal when the time delay factor exceeds a threshold value.

8. Peritoneal dialysis machine in accordance with claim 1, characterized in that the modified treatment parameter is a criterion for fixing the end of a drainage phase, preferably a minimal outflow rate.

9. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that the modified treatment parameter is the pumping rate of a dialysis pump that is configured to pump dialysis fluid from and / or to the patient.

10. Peritoneal dialysis machine in accordance with any one of the preceding claims, characterized in that at least one memory is provided in which the time delay factor is stored in the treatment protocol to enable a further processing, preferably a graphical processing of the time delay factor over a plurality of treatments.