JP5237007B2 - Blood purification equipment - Google Patents

Description

  The present invention relates to a blood purification apparatus for purifying a patient's blood while circulating it outside the body.

  In general, in blood purification therapy such as dialysis treatment, a blood circuit composed of a flexible tube is used to circulate a patient's blood extracorporeally. This blood circuit is mainly composed of an arterial blood circuit in which an arterial puncture needle for collecting blood from a patient is attached to the tip, and a venous blood circuit in which a venous puncture needle for returning blood to the patient is attached to the tip. Thus, a dialyzer is interposed between the arterial blood circuit and the venous blood circuit, and the blood circulating outside the body is purified by driving the blood pump.

  In such a dialyzer, a plurality of hollow fibers are arranged inside, and blood passes through the inside of each hollow fiber, and on the outside thereof (between the outer peripheral surface of the hollow fiber and the inner peripheral surface of the housing). It is set as the structure which can flow a dialysate. The hollow fiber has a blood purification membrane with micropores (pores) formed in the wall surface, and waste products of blood passing through the hollow fiber permeate the blood purification membrane and are discharged into the dialysate. At the same time, waste blood is discharged and purified blood returns to the patient's body. In the dialysis machine, a water removal pump for removing water from the patient's blood is disposed, and water removal is performed during dialysis treatment.

  By the way, the blood pump applied in the dialysis apparatus as described above is usually constituted by a so-called ironing type pump that squeezes a blood circuit and collects and returns a constant blood from a patient. The blood flow rate to be obtained is determined by the discharge amount per rotation of the blood pump and the number of rotations per time.

  However, since the discharge amount of the blood pump is set based on the relationship between the flow rate and the rotation speed of the blood pump under a predetermined condition (for example, when using bovine blood having a hematocrit value of about 30%) The nature of blood circulated extracorporeally does not necessarily match, and there may be a difference between the set flow rate and the actual blood flow rate (actual blood flow rate flowing through the blood circuit). Also, when blood is removed from the patient's shunt (site where arteries and veins are connected by surgery), the puncture needle is poorly punctured, the tube constituting the blood circuit in the vicinity of the puncture needle is bent, or the blood vessel is narrowed. When blood removal failure occurs, the pressure upstream of the blood pump becomes negative pressure, and the discharge amount may be less than the specified value, which may cause a deviation between the set flow rate and the actual blood flow rate.

As described above, if there is a difference between the set flow rate and the actual blood flow rate, a predetermined dialysis efficiency cannot be obtained. Therefore, it is desired to accurately detect the actual blood flow rate in order to obtain a desired dialysis efficiency. Is the actual situation. Under such circumstances, various proposals have heretofore been made for obtaining the actual blood flow (actual blood flow) flowing through the blood circuit using parameters different from the rotation speed of the blood pump. For example, as shown in Patent Document 1, blood pressure removal (hydraulic pressure in the vicinity of an arterial puncture needle in the arterial blood circuit) based on the amplitude of dialyzer inlet pressure (for example, hydraulic pressure in the drip chamber of the arterial blood circuit) And a flow rate of blood circulating outside the blood circuit (actual blood flow) from a characteristic curve indicating the relationship between the blood pressure removal and the actual blood flow that has been experimentally obtained in advance have been proposed.
JP 2006-304917 A

  However, in the above-described conventional blood purification apparatus, in order to obtain the actual blood flow rate, a characteristic relationship that is experimentally obtained in advance (specifically, the relationship between the dialyzer inlet pressure and the blood pressure reduction, and the blood pressure removal and the actual blood pressure). There is a problem that measurement errors based on individual differences among individual patients are likely to occur. Moreover, it is necessary to adjust the liquid level height of the drip chamber (arterial drip chamber) every time the actual blood flow is obtained, which is very troublesome and deteriorates workability.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a blood purification apparatus that can more accurately and easily determine the actual blood flow volume extracorporeally circulating in the blood circuit.

  The invention according to claim 1 is connected between a blood circuit composed of an arterial blood circuit and a venous blood circuit for circulating the patient's blood extracorporeally, and between the arterial blood circuit and the venous blood circuit, Blood purification means for purifying blood flowing in the blood circuit, change imparting means for imparting an artificial change to the blood of the patient extracorporeally circulating in the blood circuit, and blood in the blood of the patient extracorporeally circulating in the blood circuit In the blood purification apparatus comprising a detection means capable of detecting an index over time and detecting a change in blood index caused by an artificial change imparted by the change imparting means, the detection means comprises: It comprises a pair of sensors provided with a predetermined distance away from a site to which an artificial change is applied by the change applying means in the blood circuit, and constitutes the detecting means Measuring means for measuring a time until a change in blood index value detected by an upstream sensor is detected by a downstream sensor, and a pair of times constituting the detecting means, the time measured by the measuring means And calculating means for calculating the flow rate of the blood flowing through the blood circuit according to a predetermined calculation formula using the separation dimension of the sensor and the inner diameter dimension of the blood circuit within the separation dimension as parameters.

  According to a second aspect of the present invention, in the blood purification apparatus according to the first aspect, the change imparting unit concentrates the blood purified by the blood purification unit rapidly and in a short time, and is a peak peculiar to a change in blood concentration. And the detection means comprises a hematocrit sensor for detecting a specific peak given by the blood concentration means.

  According to a third aspect of the present invention, in the blood purification apparatus according to the first or second aspect, the mark indicating the predetermined position where the upstream sensor and the downstream sensor constituting the detection means are to be installed is the mark. It is formed in a blood circuit.

  According to a fourth aspect of the present invention, in the blood purification apparatus according to the first or second aspect, the upstream sensor and the downstream sensor constituting the detection means can be installed at predetermined positions of the blood circuit. Means are provided.

  According to a fifth aspect of the present invention, in the blood purification apparatus according to any one of the first to fourth aspects, the separation dimension of the pair of sensors constituting the detection means and the inner diameter dimension of the blood circuit within the separation dimension. It is characterized by comprising an input means for inputting.

  According to the first aspect of the present invention, the time until the change of the blood index value detected by the upstream sensor constituting the detection means is detected by the downstream sensor, and the separation of the pair of sensors constituting the detection means. Since the flow rate of the blood flowing through the blood circuit is calculated by a predetermined calculation formula using the dimensions and the inner diameter of the blood circuit within the distance as a parameter, the actual blood flow circulating outside the blood circuit can be obtained more accurately and easily. Can do.

  According to the invention of claim 2, the change imparting means comprises blood concentration means capable of concentrating the blood purified by the blood purification means rapidly and in a short time to give a peak specific to the change in blood concentration, Since the detection means is composed of a hematocrit sensor that detects a specific peak given by the blood concentration means, there is no need to inject a physiological saline or a substance serving as an indicator into the blood circuit, and the blood circuit can be simplified. The actual blood flow that circulates outside the body can be determined.

  According to the third and fourth aspects of the present invention, a mark indicating a predetermined position where the upstream sensor and the downstream sensor constituting the detection means are to be installed is formed in the blood circuit, or the upstream constituting the detection means. Since the installation means that can install the sensor on the side and the sensor on the downstream side at a predetermined position of the blood circuit is provided, the distance between the pair of sensors constituting the detection means is shifted when the actual blood flow is calculated. Can be prevented from occurring.

  According to the invention of claim 5, since the input means for inputting the separation dimension of the pair of sensors constituting the detection means and the inner diameter dimension of the blood circuit within the separation dimension is provided, the separation dimension of the pair of sensors and The actual blood flow rate can be obtained easily in response to a change in the inner diameter.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
The blood purification apparatus according to the present embodiment is for purifying a patient's blood while circulating it extracorporeally, and is applied to a hemodialysis apparatus used in hemodialysis treatment. As shown in FIG. 1, the hemodialysis apparatus mainly includes a blood circuit 1 to which a dialyzer 2 as blood purification means is connected, and a dialyzer body 6 that removes water while supplying dialysate 2 to the dialyzer 2. Has been.

  As shown in the figure, the blood circuit 1 is mainly composed of an arterial blood circuit 1a and a venous blood circuit 1b made of a flexible tube. The arterial blood circuit 1a and the venous blood circuit 1b A dialyzer 2 is connected between them. An arterial puncture needle a is connected to the tip of the arterial blood circuit 1a, and an iron-type blood pump 3 and a drip chamber 4a for defoaming are disposed on the way. On the other hand, a venous puncture needle b is connected to the distal end of the venous blood circuit 1b, and a pair of detection means (first sensor 5a and second sensor 5b) and a defoaming drip chamber 4b are provided on the way. Is connected.

  When the blood pump 3 is driven with the patient punctured with the artery side puncture needle a and the vein side puncture needle b, the patient's blood passes through the artery side blood circuit 1a while being defoamed in the drip chamber 4a. To the dialyzer 2, blood purification is performed by the dialyzer 2, and defoaming is performed in the drip chamber 4 b to return to the patient's body through the venous blood circuit 1 b. That is, the blood of the patient is purified by the dialyzer 2 while circulating outside the body by the blood circuit 1.

  The dialyzer 2 is formed with a blood introduction port 2a, a blood outlet port 2b, a dialysate inlet port 2c, and a dialysate outlet port 2d in the casing. Among these, the blood inlet port 2a has an arterial blood circuit 1a. The base end of the venous blood circuit 1b is connected to the blood outlet port 2b. The dialysate introduction port 2c and the dialysate lead-out port 2d are connected to a dialysate introduction line 7 and a dialysate discharge line 8 extending from the dialyzer body 6, respectively.

  A plurality of hollow fibers are accommodated in the dialyzer 2, the inside of the hollow fibers is used as a blood flow path, and the flow of dialysate is between the hollow fiber outer peripheral surface and the inner peripheral surface of the housing. It is considered a road. A hollow fiber membrane is formed in the hollow fiber by forming a large number of minute holes (pores) penetrating the outer circumferential surface and the inner circumferential surface, and impurities in the blood are passed through the membrane in the dialysate. It is comprised so that it can permeate | transmit.

  On the other hand, the dialysis machine body 6 includes a duplex pump P (dialysate introduction and discharge means), a bypass line 9 that bypasses the duplex pump P in the dialysate discharge line 8, and a removal that is connected to the bypass line 9. It is mainly composed of a water pump 10, a pressurizing pump 11 that causes dialysate to flow from the dialyzer 2 to the drainage side Pb of the dual pump P, a bubble separation chamber 12, an air release line 13, and a solenoid valve 14. Yes.

  The compound pump P is disposed across the dialysate introduction line 7 and the dialysate discharge line 8 and introduces dialysate from the dialysate introduction line 7 to the dialyzer 2 (blood purification means). The dialysis fluid introduced into the dialysis fluid is discharged from the dialysis fluid discharge line 8. That is, the duplex pump P is composed of a fixed type pump in which the supply side Pa and the drainage side Pb are substantially equal, and the flow path of the dialysate from the supply side Pa to the drainage side Pb is as follows. In a state where the electromagnetic valve 14 is closed, a closed system (a state in which the sealing is maintained) is established.

  The pressurizing pump 11 is connected between the dialyzer 2 and the duplex pump P in the dialysate discharge line 8 and is used to flow the dialysate from the dialyzer 2 to the duplex pump P. It consists of a positive displacement pump (pressure control type). In addition, the water removal pump 10 mentioned later shall consist of a fixed quantity type pump.

  One end of the dialysate introduction line 7 is connected to the dialyzer 2 (dialyte introduction port 2c), and the other end is connected to a dialysate supply device (not shown) for preparing a dialysate having a predetermined concentration. One end of the dialysate discharge line 8 is connected to the dialyzer 2 (dialysate outlet port 2d), and the other end is connected to a drainage means (not shown). The dialysate supplied from the dialysate supply device After passing through the dialysate introduction line 7 to the dialyzer 2, the dialysate discharge line 8 and the bypass line 9 are sent to the drainage means.

  The dewatering pump 10 is for removing water from the blood of the patient flowing through the dialyzer 2. That is, when the dewatering pump 10 is driven, since the dual pump P is of the fixed type, the volume of liquid discharged from the dialysate discharge line 8 is larger than the amount of dialysate introduced from the dialysate introduction line 7. Thus, water is removed from the blood by the large volume. In addition, you may make it remove a water | moisture content from a patient's blood by means other than this water removal pump 10 (for example, what utilizes what is called a balancing chamber etc.).

  The bubble separation chamber 12 is a so-called degassing chamber, and has a predetermined capacity connected between the pressurizing pump 11 and the dual pump P in the dialysate discharge line 8 to capture bubbles in the dialysate. It is comprised so that it can do. From the bubble separation chamber 12, the bypass line 9 described above is extended, and an air release line 13 is extended. The air release line 13 is open to the air at the tip, and an electromagnetic valve 14 is connected in the middle.

  The electromagnetic valve 14 can be opened and closed to open or close the atmosphere opening line 13 so that the bubble separation chamber 12 communicates with the outside air in the open state, and the bubble separation chamber 12 shuts off from the outside air in the closed state. It has become. Thus, before or after dialysis treatment, by operating the electromagnetic valve 14 to open the atmosphere release line 13, the bubbles trapped in the bubble separation chamber 12 can be released to the atmosphere.

  In addition, the air release line 13 and the electromagnetic valve 14 in the present embodiment constitute the blood concentration means (change imparting means) of the present invention, and the air release line 13 is opened by operating the electromagnetic valve 14. Thus, the blood flowing through the dialyzer 2 can be concentrated rapidly and for a short time to give a specific peak to the blood index (blood index). That is, during the dialysis treatment, when the solenoid valve 14 is operated to open the closed air release line 13, the outlet pressure of the pressurizing pump 11 becomes substantially equal to the atmospheric pressure. A high negative pressure is instantaneously generated, and rapid and short-time water removal (blood concentration) is performed on the blood flowing through the dialyzer 2 (blood flow path).

  As a result, it is much larger than the ultrafiltration pressure generated by driving the water removal pump 10, and a large amount of water can be removed from the blood in a short time, and the blood concentration (hematocrit value) as a blood index can be obtained. ) To give a peculiar peak. It should be noted that the opening of the atmosphere opening line 13 by the electromagnetic valve 14 takes a short time (in this embodiment, the opening of the atmosphere opening line 13 can be set to an arbitrary time of 10 seconds or less, 0.5 seconds or Even below that, it has sufficient measurement accuracy), and the air release line 13 is closed by immediately operating the solenoid valve 14.

  Here, the term “abrupt and short time” in the present invention means a size and time enough to confirm the pulse applied after passing through the circuit, and “specific” means fluctuations in the pump and the body of the patient. It can be distinguished from fluctuation patterns due to other factors caused by movement. In addition, the water removal speed by this embodiment is 10 times or more of normal water removal.

  The patient's blood concentration information may be the patient's blood concentration (hematocrit value, hemoglobin concentration, etc.) itself, or venous pressure (for example, the air layer of the drip chamber 4b) that is the pressure of blood flowing through the venous blood circuit 1b. Or the dialysate pressure (the dialysate pressure immediately after the dialyzer 2 in the dialysate discharge line 8), which is the dialysate pressure derived from the dialyzer 2. The blood concentration information of the patient is obtained from the hematocrit sensor disposed in the venous blood circuit 1b and the venous pressure (for example, the pressure of the air layer in the drip chamber 4b) that is the pressure of blood flowing in the venous blood circuit 1b. It may be derived from (venous pressure).

  However, it is preferable that the rotation speed of the pressurizing pump 11 can be arbitrarily changed when the atmosphere opening line 13 is opened by the electromagnetic valve 14. Thereby, the magnitude of the applied negative pressure can be controlled. In the case of an alarm device such as a dialysate pressure alarm, a venous pressure alarm, or a dialyzer inlet pressure alarm, the alarm width by the alarm device (the alarm should be alarmed for a certain period of time from the opening of the air release line 13 by the electromagnetic valve 14). The range) may be expanded to suppress false alarms. In order to further suppress false alarms, the alarm monitoring by the alarm device may be relaxed for a certain time from the time when the atmosphere release line 13 is opened by the electromagnetic valve 14.

  The first sensor 5a and the second sensor 5b constituting the detection means of the present invention detect a blood index (hematocrit value) in the patient's blood circulating extracorporeally in the blood circuit 1 over time, and open the atmosphere open line 13 and the electromagnetic wave. A change in blood index caused by an artificial change (abrupt and short-time change in blood concentration) applied by the valve 14 (blood concentration means (change providing means) of the present invention) can be detected.

  More specifically, the first sensor 5a and the second sensor 5b constituting the detection means of the present invention are disposed between the venous drip chamber 4b of the venous blood circuit 1b and the venous puncture needle b. It consists of a pair of sensors. Thus, the pair of the first sensor 5a and the second sensor 5b is downstream (this embodiment) from the site (the dialyzer 2 in this embodiment) to which the artificial change is given by the change giving means in the blood circuit 1. In FIG. 2, the blood vessel is provided in the venous blood circuit 1b) while being separated by a predetermined dimension L.

  The first sensor 5a and the second sensor 5b are composed of a hematocrit sensor capable of detecting blood concentration. The hematocrit sensor includes a light emitting element such as an LED and a light receiving element such as a photodiode. The hematocrit value indicating the blood concentration of the patient is detected by irradiating light to the light and receiving the transmitted light or reflected light with a light receiving element.

  Specifically, a hematocrit value indicating the blood concentration is obtained based on the electrical signal output from the light receiving element. That is, each component such as red blood cell and plasma that constitutes blood has a specific light absorption characteristic, and by using this property, red blood cells necessary for measuring a hematocrit value are optically quantified. The hematocrit value can be obtained. More specifically, near infrared rays irradiated from the light emitting element are incident on blood, are affected by absorption and scattering, and are received by the light receiving element. The light absorption / scattering rate is analyzed from the intensity of the received light, and the hematocrit value is calculated.

  Here, in the present embodiment, the measuring means 15 and the calculating means 16 are disposed in the dialysis apparatus body 6. The measuring means 15 is electrically connected to each of the pair of first sensor 5a and second sensor 5b, and a change in blood index value (change in hematocrit value) detected by the upstream first sensor 5a among the sensors. ) Until the second sensor 5b on the downstream side is detected (movement time t).

  For example, a change in hematocrit value caused by an artificial change (a rapid and short-time change in blood concentration) imparted by the open air line 13 and the electromagnetic valve 14 (blood concentration means (change imparting means) of the present invention). The (specific peak) is first detected by the first sensor 5a on the upstream side, and then detected by the second sensor 5b on the downstream side. However, the time from when the maximum value A 'of the specific peak is detected in the first sensor 5a to the time when the maximum value A' of the specific peak is detected in the second sensor 5b is the movement time t.

  As a method for measuring the movement time t, in addition to the above-described method, for example, a change of a specific peak in the second sensor 5b from a certain point after a change rate of a specific peak in the first sensor 5a is detected. A method of setting a time until the rate is detected, or a specific peak area S ′ (detected by the second sensor 5b from the time when the specific peak area S detected by the first sensor 5a is detected). For example, there may be mentioned a method of setting the time until the point when the same area S as the first sensor 5a is detected.

  The calculating means 16 includes the time (t) measured by the measuring means 15, the separation dimension (L) of the pair of sensors (the first sensor 5a and the second sensor 5b) constituting the detection means, and the blood circuit within the separation dimension (L). The flow rate of blood flowing through the blood circuit 1 (actual blood flow) is calculated by a predetermined calculation formula using the inside diameter dimension (D) of the venous blood circuit 1b) as a parameter. The separation dimension (L) and the inner diameter dimension (D) are preset values and are known parameters with time (t).

The calculation formula of the calculation performed by the calculation means 16 is as follows. However, the in-circuit capacitance (B) is obtained by the equation (D / 2) ² × π × L, the unit is (mL), and the time (t) is the unit (s). .
Actual blood flow (mL / min) = capacitance in circuit (B) × 60 / hour (t) (calculation formula)

  Therefore, according to the present embodiment, the time (t) measured by the measuring unit 15, the separation dimension (L) of the pair of sensors (first sensor 5 a and second sensor 5 b) constituting the detection unit, and within the separation dimension The actual blood flow volume of the blood circulating outside the blood circuit 1 can be obtained by the predetermined arithmetic expression as described above using the inner diameter dimension (D) of the blood circuit (venous side blood circuit 1b) as a parameter. The actual blood flow rate can be determined more accurately and easily than the method for obtaining the actual blood flow rate based on the relationship between the discharge amount and the rotational speed, or the method for deriving the actual blood flow rate from a double experimental relationship, etc. .

  In addition, the change applying means according to the present embodiment is a blood concentrating means (atmospheric release line 13 and the air opening line 13) capable of concentrating blood purified by the blood purifying means rapidly and in a short time to give a peculiar peak to the change in blood concentration. Since the detection means (the first sensor 5a and the second sensor 5b) is composed of a hematocrit sensor for detecting a specific peak given by the blood concentration means, the detection means (the first sensor 5a and the second sensor 5b) includes a physiological saline and an indicator. There is no need to inject a substance or the like into the blood circuit 1, and the actual blood flow that circulates outside the blood circuit more easily can be obtained.

  It should be noted that a mark (for example, a position indicating a position at which the separation dimension is accurately set to L) where the upstream sensor (first sensor 5a) and the downstream sensor (5b) constituting the detection means should be installed (for example, The blood circuit 1 is formed with a mark that can be visually recognized, such as printing or engraving, or the upstream sensor (first sensor 5a) and the downstream sensor (second sensor 5b) constituting the detection means. Installation means (for example, a cassette-type one that can mount the first sensor 5a and the second sensor 5b at a predetermined position) that can be installed at a predetermined position (a position at which the separation dimension is accurately set to L). Good. In this case, when calculating the actual blood flow rate, it is possible to prevent an error from occurring due to a shift in the distance between the pair of sensors (the first sensor 5a and the second sensor 5b) constituting the detection means.

  Although the present embodiment according to the present invention has been described above, the present invention is not limited to this. For example, the blood circuit 1 can be formed by injecting a physiological saline solution or an indicator substance into the blood circuit 1. The change applying means for applying an artificial change to the blood of the patient circulating extracorporeally, and the detecting means (first sensor 5a and second sensor 5b) are blood in the blood of the patient extracorporeally circulating in the blood circuit 1. The index may be detected over time and a change in blood index caused by an artificial change given by the change giving means may be detected. Even in this case, the time from the change of the blood index caused by the artificial change from the first sensor 5a to the second sensor 5b may be measured by the measuring means 15 to be the moving time (t). it can.

  In the dewatering pump 10 according to this embodiment as well, by driving it rapidly in a short time, the blood flowing in the dialyzer 2 can be concentrated rapidly and in a short time to give a specific peak. ing. That is, the blood flowing through the blood flow path of the dialyzer 2 is concentrated by rapidly filtering the water through the blood purification membrane to the dialysate flow path side in a short time, and this appears as a specific peak. .

  Furthermore, in the above embodiment, the separation dimension L of the first sensor 5a and the second sensor 5b and the inner diameter dimension D of the blood circuit 1 within the separation dimension L are fixed (invariable) and are known parameters. For example, the input means for inputting the separation dimension (L) of the pair of sensors (first sensor 5a and second sensor 5b) constituting the detection means and the inner diameter dimension (D) of the blood circuit 1 within the separation dimension (L). You may make it comprise. In this case, when the separation dimension (L) and the inner diameter dimension (D) of the pair of sensors (the first sensor 5a and the second sensor 5b) change, it can be easily handled (specifically, input to the input means). The actual blood flow rate can be obtained.

  In this embodiment, the dialysis device body 6 is composed of a dialysis monitoring device that does not incorporate a dialysate supply mechanism, but may be applied to a personal dialysis device that incorporates a dialysate supply mechanism. . Furthermore, it can be applied to those used in other treatments (blood filtration therapy, hemofiltration dialysis therapy, etc.) for purifying blood while circulating extracorporeally, or those to which other functions are added.

  A detecting means comprising a pair of sensors provided at a predetermined distance downstream from a site to which an artificial change is applied by the change applying means in the blood circuit, and an upstream of the sensors constituting the detecting means; Measuring means for measuring the time until the change in blood index value detected by the sensor on the side is detected by the downstream sensor, the time measured by the measuring means, the separation dimension of the pair of sensors constituting the detecting means, and A blood purification device provided with a calculation means for calculating the flow rate of blood flowing through the blood circuit by a predetermined calculation formula using the inner diameter dimension of the blood circuit within the separation dimension as a parameter, and having a different external shape or other functions It can also be applied to those to which is added.

1 is an overall schematic view showing a blood purification apparatus according to an embodiment of the present invention. The graph which shows the change of the hematocrit value detected with the 1st sensor and the 2nd sensor which comprise the detection means in the blood purification apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Blood circuit 1a ... Arterial side blood circuit 1b ... Vein side blood circuit 2 ... Dializer (blood purification means)
3 ... blood pump 4a, 4b ... drip chamber 5a ... first sensor (detection means)
5b ... 2nd sensor (detection means)
DESCRIPTION OF SYMBOLS 6 ... Dialyzer main body 7 ... Dialysate introduction line 8 ... Dialysis system discharge line 9 ... Bypass line 10 ... Dewatering pump 11 ... Pressurizing pump 12 ... Bubble separation chamber 13 ... Air release line 14 Solenoid valve 15 Measuring means 16 Calculation means P Duplex pump

Claims (5)

A blood circuit comprising an arterial blood circuit and a venous blood circuit for extracorporeal circulation of the patient's blood;
Blood purification means connected between the arterial blood circuit and the venous blood circuit and purifying blood flowing through the blood circuit;
A change imparting means for imparting an artificial change to the blood of the patient circulating extracorporeally in the blood circuit;
Detecting means capable of detecting a blood index in the blood of a patient circulating extracorporeally in the blood circuit with time, and detecting a change in blood index caused by an artificial change given by the change giving means;
In the blood purification apparatus comprising
The detection means comprises a pair of sensors provided with a predetermined distance away from the site where the artificial change is applied by the change applying means in the blood circuit.
A measuring means for measuring a time until a change in blood index value detected by an upstream sensor among the sensors constituting the detecting means is detected by a downstream sensor;
The flow rate of blood flowing through the blood circuit is calculated according to a predetermined arithmetic expression using the time measured by the measuring means, the separation dimension of the pair of sensors constituting the detection means, and the inner diameter dimension of the blood circuit within the separation dimension as parameters. Computing means for
A blood purification apparatus comprising:   The change imparting means comprises blood concentration means capable of concentrating the blood purified by the blood purification means rapidly and in a short time to give a peak peculiar to a change in blood concentration, and the detection means comprises the blood 2. The blood purification apparatus according to claim 1, comprising a hematocrit sensor for detecting a specific peak given by the concentration means.   3. The blood purification according to claim 1, wherein a mark indicating a predetermined position where an upstream sensor and a downstream sensor constituting the detection means are to be installed is formed in the blood circuit. apparatus.   The blood purification apparatus according to claim 1 or 2, further comprising installation means capable of installing an upstream sensor and a downstream sensor constituting the detection means at predetermined positions of the blood circuit.   5. The input device according to claim 1, further comprising: an input unit configured to input a separation dimension of the pair of sensors constituting the detection unit and an inner diameter dimension of the blood circuit within the separation dimension. Blood purification device.

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