JP6523614B2 - Dehydrator for used dialysate and dialysate regeneration system using the same - Google Patents

Description

  The present invention relates to a water removal unit for removing part of water from used dialysate and a dialysate regeneration system using the same.

  In patients suffering from renal failure, the reduced renal function does not allow the blood to excrete excess water, excess potassium and so-called toxins (eg nitrogen metabolites such as urea and creatinine) adequately outside the body. For such patients, artificial dialysis is performed to artificially excrete excess water and the like in the blood. There are mainly hemodialysis and peritoneal dialysis in artificial dialysis.

  Hemodialysis is a dialysis process in which a patient's blood is passed through a dialyzer. In the dialyzer, a blood compartment through which blood flows and a dialysate compartment through which dialysate flows are separated by a semipermeable membrane. Excess water and the like in the blood move to the dialysate side through the semipermeable membrane. The dialyzed blood which has passed through the blood compartment of the dialyzer is returned to the patient as it is. Hemodialysis needs to be performed at a hospital equipped with a dialysis facility.

Peritoneal dialysis is a dialysis process performed by storing dialysate in the abdominal cavity of the human body. The abdominal cavity is surrounded by the peritoneum which functions as a semipermeable membrane. When dialysate is stored in the abdominal cavity, excess water and the like in the blood move into the dialysate through the peritoneum. The dialysate is excreted outside the body after being stored in the abdominal cavity for a certain period of time.
In the abdomen of a patient who carries out peritoneal dialysis, a catheter that connects the inside of the abdominal cavity and the outside of the body is embedded. Supply and discharge of dialysate into the abdominal cavity is performed via the catheter. When dialysate is supplied into the abdominal cavity, the dialysate bag containing the dialysate and the catheter are connected by a tube, and the dialysate bag is placed at a higher position than the catheter. As a result, the dialysate naturally flows into the abdominal cavity by its own weight. On the other hand, when used dialysate is drained from the abdominal cavity, a drainage bag for storing the used dialysate and a catheter are connected by a tube, and the drainage bag is disposed at a lower position than the catheter. Thereby, the dialysate is naturally discharged from the abdominal cavity by its own weight. Patients can perform dialysis treatment at home.

  The used dialysate after dialysis treatment contains potassium and low molecular weight toxins (urea, creatinine, etc.) not contained in the one before use. In addition, the amount of water in the dialysate after use is increased as compared to that before use. Therefore, the used dialysate could not be reused and was discarded.

On the other hand, peritoneal dialysis patients need to store the dialysate used for daily dialysis at home. As dialysate is used approximately 8 liters a day, in order to store several weeks to one month's worth of dialysate, patients have room for home to store tens to hundreds of liters of dialysate. There is a need.
In addition, in a wide-area disaster such as a large-scale earthquake, it is difficult to secure the dialysate, which may make it impossible to perform sufficient dialysis treatment.
In order to solve these problems, it has been considered to regenerate and reuse the used dialysate without discarding it.

  The used dialysate has a reduced amount of water as compared to the dialysate before use, and as a result, the concentration of contained carbohydrates is reduced, resulting in a decrease in osmotic pressure. In addition, the used dialysate contains potassium and toxin which were not contained in the dialysate before use. Therefore, in order to regenerate the used dialysate, it is necessary to remove a portion of the water to further increase the osmotic pressure, and further to remove the potassium and the toxin.

  Known methods for removing toxins from dialysate and regenerating dialysate include methods using ultrafiltration (patent documents 1 and 2) and methods using adsorption means for adsorbing toxins (patent document 3) . Either way, it is necessary to use a regeneration device that includes a pump.

JP 10-85324 A JP 2011-505209 gazette Japanese Patent Application Publication No. 2007-516793

Pumps suitable for ultrafiltration and the like are relatively large, and the dialysate regenerator including such pumps is also large and thus not suitable for home use. Therefore, it is not practical to regenerate used dialysate at home, and used dialysate was discarded without being regenerated.
Also, in situations where it is difficult to secure power, such as in a large-scale disaster, those reproduction devices can not be used.

  Then, an object of this invention is to provide the water removal machine for reproducing | regenerating a dialysate, and a dialysate regeneration system using the same, without using the electric equipment containing a pump.

The present invention is a water removal device for removing a portion of water contained in used dialysate, comprising:
A casing having a first compartment for circulating used dialysate and a second compartment separated from the first compartment by a semipermeable membrane;
An aqueous solution retained in the second compartment for removing a portion of the water from the used dialysate through the semipermeable membrane, wherein the aqueous solution is at least 1.5 times the molecular weight cut off of the semipermeable membrane And an aqueous solution containing a polymer compound having a molecular weight.
The aqueous solution contains water and a polymer compound dissolved in water, and can optionally contain a potassium removal agent and the like.

According to the present invention, by holding the aqueous solution for water removal in the second compartment, the osmotic pressure of the aqueous solution to the used dialysate is increased, and as a result, the first separated by the semipermeable membrane A portion of the water from the dialysate can be transferred into the aqueous solution (i.e., dialysate removal) when the spent dialysate is circulated through the compartments. Also, along with water removal from the dialysate, potassium and toxins in the dialysate can also be transferred into the aqueous solution.
In the present specification, a part of water in the used dialysate is removed, and the state of removal of potassium and toxin is also referred to as "regeneration" as the water is eliminated. Here, "a portion of water" refers to a proportion corresponding to water substantially increased by, for example, peritoneal dialysis. The water removal amount can be controlled, for example, by the concentration of the polymer compound dissolved in the aqueous solution.

  In addition, since the molecular weight of the polymer compound contained in the aqueous solution for water removal is 1.5 times or more of the molecular weight cut-off of the semipermeable membrane, the migration of the polymer compound from the aqueous solution to the dialysate should be suppressed. Can. Thereby, it is possible to suppress the migration of the polymer compound into the dialysate during water removal, and to suppress the rapid decrease of the osmotic pressure of the aqueous solution for water removal.

  As an example of the most preferred embodiment, the present invention comprises a semipermeable membrane having a molecular weight cut-off of 10000 to 13000, for example 11800, and a water-removal water holding an aqueous solution dissolving polyethylene glycol with a weight average molecular weight of 20000 in the second section. Provide the The concentration of polyethylene glycol in the aqueous solution can be 10 to 30% by weight, preferably 20% by weight. The aqueous solution preferably further contains a potassium removal agent.

  According to the present invention, the osmotic pressure of the aqueous solution for water removal transfers a portion of the water from the used dialysate to the aqueous solution side, along with which the potassium and toxin also move from the used dialysate to the aqueous solution side By doing this, the used dialysate is regenerated. Thus, since the present invention does not use the ultrafiltration used in the conventional regeneration method, the dialysate can be regenerated without using the pump required for the ultrafiltration.

FIG. 1 is a schematic view of a water removal device according to a first embodiment of the present application. FIG. 2 is a schematic view of a dialysate regeneration system according to a second embodiment of the present invention. FIG. 3 is a partial enlarged view of FIG. FIG. 4 is a bar graph showing the measurement results of Example 1. FIG. 5 is a line graph showing the measurement results of the second embodiment.

Embodiment 1
Hereinafter, embodiments of the present invention will be described in detail based on the drawings.
The water removal device 10 shown in FIG. 1 is for removing a part of water from used dialysate. The water removal device 10 includes a cylindrical casing 14 and a hollow fiber semipermeable membrane 13. The semipermeable membrane 13 is disposed in the lumen of the casing 14, and its both ends can be connected to two lines (first line 21, second line 22) extending from both ends of the casing 14. In addition, although the water removal machine 10 provided with one hollow fiber semipermeable membrane 13 is conveniently shown for convenience of understanding in FIG. 1, the thin hollow fiber semipermeable membrane is normally The water dehydrator 10 provided with many is used.
The casing 14 is separated into two compartments by a semipermeable membrane. The first compartment 11 is composed of the lumen of the semipermeable membrane 13, through which spent dialysate flows. The second section 12 is constituted of a space between the semipermeable membrane 13 and the casing 14 and holds an aqueous solution 15 for water removal containing a polymer compound. The concentration of the macromolecular compound in the aqueous solution 15 is adjusted to have a higher osmotic pressure than the used dialysate.

  At the time of use of the water removal device 10, the used dialysate flows from the first line 21 into the first compartment 11 along the arrow 11a, passes through the first compartment 11, and is then subjected to dialysis after water removal. A fluid, ie regenerated dialysate 52, flows out of the second line 22 along the arrow 11b. When the spent dialysate passes through the first compartment 11, if the aqueous solution 15 for water removal exists through the semipermeable membrane 13, the used dialysate due to the osmotic pressure difference between the spent dialysate and the aqueous solution 15 A portion of the water in the water transfers to the aqueous solution 15 through the semipermeable membrane 13. In addition, when water moves, low molecular weight toxins (urea, creatinine, etc.) depending on the partial molecular weight of potassium and semipermeable membrane contained in the used dialysate pass through the semipermeable membrane 13 and the aqueous solution 15 Move to As a result, the used dialysate has a reduced amount of water and also reduced the content of potassium and low molecular weight toxins (urea, creatinine etc.). By making the amount of water contained in the regenerated dialysate approximately the same as the amount of water in the dialysate before use, the water removal capacity of the regenerated dialysate (removing excess water from the blood during dialysis) Ability to recover). Also, when removing part of the water from the spent dialysate, both potassium and toxin are removed, so the content of potassium and toxin contained in the regenerated dialysate can be reduced (eg 30 mmol of potassium) / L or less). Therefore, it is possible to restore the ability of the regenerated dialysate to remove potassium and toxin (the ability to remove potassium and toxin etc. from the blood during dialysis). As described above, by using the water remover 10, it is possible to restore the water removal ability required for the dialysate and the removal ability of potassium etc. (that is, regeneration of the dialysate). The regenerated dialysate can be used again for dialysis as a regenerated dialysate, but in accordance with the composition of the regenerated dialysate, if necessary, it is preferable to adjust the components for reuse.

As used herein, "used dialysate" means, in peritoneal dialysis, dialysate removed from the peritoneal cavity, and in hemodialysis, means dialysate after passing through the dialyzer.
Also, "removing a portion of water" is to reduce the amount of water in the used dialysate in order to increase the osmotic pressure of the used dialysate. The amount of water to be removed is about 60 to 100%, preferably 70 to 100%, of the amount of water increased by dialysis (amount of used dialysate-amount of dialysate before use). Can restore the water removal ability of
Furthermore, "an aqueous solution for water removal containing a polymer compound" is an aqueous solution for removing a part of water from a dialysate through a semipermeable membrane, and has a higher osmotic pressure than a used dialysate. The concentration of the macromolecular compound is adjusted.

  Since this water removal device 10 removes water using an osmotic pressure difference, it does not require a pump, unlike, for example, a conventional dialysate regeneration device using ultrafiltration. Therefore, the dialysate can be regenerated even in a situation where it is difficult to secure the power supply (for example, a large-scale disaster). In addition, this water removal device 10 can use a general hemodialysis dialyzer (for example, a diameter of 3 to 4 cmφ, a length of 30 cm), and a relatively large pump used for ultrafiltration. It can be made smaller than the conventional dialysate regenerator used.

  When the concentration of the polymer compound in the aqueous solution 15 for water removal decreases, the osmotic pressure decreases, so the ability to remove water from the used dialysate decreases. When the used dialysate is continuously regenerated, the concentration of the macromolecular compound in the aqueous solution 15 gradually decreases due to the water removed from the used dialysate. Here, if the polymer compound passes through the semipermeable membrane 13, the concentration of the polymer compound in the aqueous solution 15 is reduced, and the osmotic pressure is also significantly reduced. Therefore, by setting the molecular weight (Mw) of the polymer compound to be dissolved in the aqueous solution 15 to be 1.5 times or more of the fractional molecular weight of the semipermeable membrane 13, the migration of the polymer compound to the used dialysate is substantially It is possible to prevent the reduction of the osmotic pressure of the aqueous solution 15 by

  In addition, "fractionated molecular weight" is used in the field of dialysis, correlates with the pore diameter of the semipermeable membrane, and indicates a molecular weight having a specific solute permeation inhibition rate of 90% on the fractionation curve. As a specific example, in the functional division of the hemodialyzer on the medical service fee, the type I dialyzer has a low clearance value of less than 10 mL / min of β2 microglobulin (β2 MG) with a molecular weight of 11800, and β2 MG is blocked with hardly passing through Ru. Therefore, the molecular weight cut-off of the semipermeable membrane used for the dialyzer can be considered to be approximately 11800.

Moreover, "molecular weight" is a weight average molecular weight (Mw), and can be calculated by the following method. ... First of all, JIS K 0070 (Test method of acid value, saponification value, ester value, iodine value, hydroxyl value and unsaponification value of chemical products) 7.1 (neutralization titration method) using 20 g of a sample of a polymer compound Calculate the hydroxyl value along with). The weight average molecular weight is determined by the following equation 1 using the obtained hydroxyl value.
A = 56106 / B × C (Equation 1)
here,
A: Average weight molecular weight B: Hydroxyl value C: The number of hydroxyl groups per molecule (2 for polyethylene glycol).

The molecular weight cut-off of the semipermeable membrane 13 is preferably 44000 or less, more preferably 10000 to 33000, and more preferably 10000 to 13000, so that plasma protein components such as albumin (molecular weight about 66000) will not pass through. Is particularly preferred. The plasma protein component is a component that leaks from the blood into the dialysate during peritoneal dialysis, and is desirably retained in the regenerated dialysate for the following reasons.
Since the plasma protein component is contained in the living body, it is highly biocompatible and can be a component that enhances the osmotic pressure of the dialysate. Although the dialysate before use contains carbohydrates of a predetermined concentration to impart water removal ability, it is said that part of the carbohydrates can be absorbed from the dialysate into the body during peritoneal dialysis. In that case, the osmotic pressure of the dialysate decreases. Therefore, in order to restore the water removal capacity of the dialysate, not only water removal but also addition of carbohydrates may be necessary. However, by leaving the plasma protein component in the regenerated dialysate, the plasma protein component can compensate for the decrease in the osmotic pressure of the dialysate due to the absorbed carbohydrate, that is, the decrease in the water removal rate of the dialysate. Therefore, when recycling the regenerated dialysate, the addition of carbohydrates can be unnecessary or the amount of addition can be reduced. In particular, carbohydrates are said to have the potential to adversely affect body tissues, and in peritoneal dialysis where dialysate is in direct contact with the peritoneal membrane, it causes peritoneal diseases such as peritonitis and entrapment peritoneal sclerosis. It is also said to be the cause. By leaving the plasma protein component in the regenerated dialysate, it can be used as a dialysate with a low concentration of carbohydrates, so it is considered that the occurrence of diseases associated with peritoneal dialysis can be reduced. This may possibly extend the application period of peritoneal dialysis, which is conventionally said to be 5 to 7 years.
In addition, when the molecular weight cut-off of the semipermeable membrane 13 is in the range of 10000 to 13000, a general medical semipermeable membrane (for example, a semipermeable membrane used in an I-type dialyzer (fractional molecular weight 11800)) There is also an advantage that can be used.

  When the molecular weight cut-off of the semipermeable membrane 13 is 10,000 to 13,000, the polymer compound to be dissolved in the aqueous solution 15 for water removal has an average molecular weight of 15,000 or more (1.5 times or more than that in the case of the molecular weight cut off 10000 or Or higher (2 times or more (twice or more than in the case of a molecular weight cut off of 10000) or more, and more preferably 20000 to 50000 (2 to 5 times a molecular weight cut off of 10000) Is more preferred.

  As the polymer compound, those which are water soluble and whose biological safety has been confirmed are desirable. As described above, most polymer compounds do not pass through the semipermeable membrane 13 because the average weight molecular weight of the polymer compounds is 1.5 times or more of the molecular weight cut off. However, a trace amount of polymer compound may pass through the semipermeable membrane 13 and be mixed in the dialysate. When the regenerated dialysate is used for peritoneal dialysis or the like, there is a possibility that a trace amount of polymer compound in the dialysate may be introduced into the living body. Therefore, macromolecular compounds whose biological safety has not been confirmed or which are toxic are not preferable.

Specific examples of suitable polymer compounds include polyethylene glycol (PEG), polyvinyl pyrrolidone (PVP), polyethylene oxide (PEO), acrylic acid polymers, polysaccharides, mucopolysaccharides, and proteins of biological origin. It is one kind. Examples of polysaccharides include carboxymethylcellulose and sucralose. Examples of mucopolysaccharides include hyaluronic acid, chondroitin sulfate, heparin and the like. Examples of proteins of biological origin include albumin, globin, globulin and the like.
In particular, water-soluble polyethylene glycol (PEG) is preferable, and one having a desired molecular weight (for example, a molecular weight of 20000) and a narrow molecular weight distribution is preferable because it is easily available and its biological safety has been confirmed.

Generally, the concentration of the macromolecular compound in the aqueous solution 15 for water removal is preferably 10% by weight or more, more preferably 10 to 50% by weight, before use (that is, the initial concentration). % Is particularly preferable, and appropriate removal of water from used dialysate can be performed.
In the case of the aqueous solution 15 using polyethylene glycol having a molecular weight of 20000 as the polymer compound, it is preferably 5 mmol / L (10% by weight) or more, and is 5-25 mmol / L (10 to 50% by weight) More preferably, it is particularly preferably 5 to 15 mmol / L (10 to 30% by weight).

  The aqueous solution 15 for water removal preferably contains a potassium removal agent such as sodium polystyrene sulfonate. In the case of a patient with high potassium concentration in blood (hyperkalemia), it may be fatal condition such as cardiac arrest, so it is necessary to reduce the potassium concentration rapidly. Therefore, it is desirable to lower the potassium concentration of the dialysate as much as possible to enhance the ability to remove potassium from blood. Therefore, by adding a potassium removal agent to the aqueous solution 15, more potassium can be removed from the used dialysate, and a regenerated dialysate with a low potassium concentration can be obtained.

Hereinafter, a water removal method using the water removal device 10 will be described.
1. Preparation of Dehydrator 10 Prepare casing 14 with semipermeable membrane 13 and use aqueous solution 15 for dewatering in the second compartment 12 along the arrow 12a from the upper line 25 connected to the second compartment 12 Inject. Since the second compartment 12 surrounds the hollow filamentous semipermeable membrane 13, the aqueous solution 15 is injected into the second compartment 12 to contact the entire outer surface of the hollow filamentous semipermeable membrane 13.

Next, the used dialysate is continuously supplied to the first compartment 11 of the water removal device 10. The spent dialysate is supplied from the first line 21 in the direction of the arrow 11a. In the first compartment 11, a portion of the water in the used dialysate is transferred to the aqueous solution 15 in the second compartment 12 through the semipermeable membrane 13 by the osmotic pressure of the aqueous solution 15 for water removal. The transfer amount of water can be controlled by the polymer concentration of the aqueous solution 15 and the flow rate of the used dialysate.
The flow rate of the used dialysate is preferably 5 ml / min or more, more preferably 10 ml / min or more, and particularly preferably 10 to 30 ml / min. When the initial concentration of the aqueous solution 15 is 10% by weight or more, an appropriate water removal effect can be obtained at a flow rate in this range.

Then, the dialysate (regenerated dialysate) whose water has been drained is continuously discharged from the first compartment 11 to the second line 22 in the direction of the arrow 11 b.
The regenerated dialysate discharged from the second line 22 may be used as it is for dialysis, or it may be used for dialysis after adding additives so as to obtain a convenient composition by dialysis. As an additive, for example, when the water removal amount is too large, water can be added to make the sugar concentration suitable for dialysis. Also, if the concentration of carbohydrates is too low, carbohydrates can be added.

In addition, since the volume of the aqueous solution 15 for water removal increases by water removal, it is necessary to discharge the aqueous solution 15 of the quantity equivalent to volume increase from the 2nd division 12. FIG. For example, the lower line 24 connected to the second compartment 12 is normally closed by a clamp or the like so that the aqueous solution 15 does not flow out, but the amount of the aqueous solution 15 can be increased by appropriately opening the clamp. It can be discharged. If the degree of opening of the line can be adjusted according to the degree of tightening of the clamp, the degree of tightening of the clamp may be adjusted so that a small amount of aqueous solution 15 is continuously discharged from the line 24. Good.
Further, in the aqueous solution 15, the concentration of the polymer compound is gradually decreased by water removal from the used dialysate. Then, when the osmotic pressure of the aqueous solution 15 becomes equal to the osmotic pressure of the used dialysate, the water removal device 10 can not remove water from the used dialysate. Therefore, after dewatering a predetermined amount of used dialysate (for example, used dialysate equivalent to one peritoneal dialysis), used aqueous solution 15 is replaced with fresh aqueous solution 15. Thus, the used dialysate can be removed again by the water remover 10. When the aqueous solution 15 is replaced, the used aqueous solution 15 is discharged from the fourth line 24, and after completely discharged, the new aqueous solution 15 is allowed to flow from the fifth line 25.

Second Embodiment
In the present embodiment, a dialysate regeneration system using the water removal device 10 of the first embodiment will be described.
FIG. 2 shows an example of a dialysate regeneration system 20 used in peritoneal dialysis. The dialysate regeneration system 20 includes the water remover 10 according to the first embodiment and a reservoir 26 for storing the dialysate 52 removed by the water remover 10. Furthermore, the dialysate regeneration system 20 comprises a plurality of lines for flowing dialysate. The first line 21 allows the used dialysate 51 that has flowed out of the dialysis area (in FIG. 2, the abdominal cavity) 90 to flow into the first section 11 of the casing 14 of the water removal device 10. The second line 22 allows the drained dialysate 52 discharged from the first compartment 11 to flow into the reservoir 26. Then, the third line 23 allows the drained dialysis fluid (regenerated dialysis fluid) 52 to flow into the abdominal cavity 90 from the reservoir 26.

The dialysate regeneration system 20 according to the present embodiment has a configuration in which the water removal device 10 and the reservoir 26 are connected in series in a line starting from the abdominal cavity 90 and returned to the abdominal cavity 90 again. That is, the dialysate regeneration system 20 does not expose the outside air until the used dialysate 51 in the abdominal cavity 90 is dewatered by the water remover 10 and returned to the abdominal cavity 90 as the regenerated dialysate 52, A so-called closed circuit is configured. Thus, the dialysate is less likely to be contaminated during regeneration.
A filter 32 can be installed in the first line 21 as needed. As a result, it is possible to prevent clogging of the semipermeable membrane 13 of the water removal device 10 by removing fibrin aggregates and the like.
In this embodiment, although the dialysate regeneration system 20 is described as an example of peritoneal dialysis performed in the abdominal cavity 90, the dialysis fluid is removed from the dialysate used for dialysis treatment by connecting a dialyzer instead of the peritoneal cavity 90. The dialysate regeneration system 20 can also be used for hemodialysis by regenerating the dialysate. That is, the dialysate regeneration system 20 can form a closed circuit by connecting to a dialysis area (an area where dialysis is being performed, the peritoneal cavity 90 for peritoneal dialysis, and the dialyzer for hemodialysis). It is a reproduction system 20.

The dialysate regeneration system 20 further includes two lines (the lower line 24 (referred to as a fourth line 24 in this embodiment) and the upper line 25 (a fifth line 25 in the present embodiment). Can be included). The fourth line 24 discharges the used aqueous solution 15 b from the second compartment 12 of the casing 14. The fifth line 25 injects the unused aqueous solution 15 a into the second compartment 12.
The fifth line 25 can connect one or more cartridges 27 (two cartridges 271 and 272 in FIG. 3) filled with the unused aqueous solution 15a. Thereby, exchange of aqueous solution 15 of water removal machine 10 can be performed simply. The cartridge 27 is filled with a sufficient amount (for example, 50 ml) of the unused aqueous solution 15 a to fill the second compartment 12.
As shown in detail in FIG. 3, when a plurality of cartridges 27 are provided, the fifth line 25 is branched into a plurality (in FIG. 3, the first branch line 251 and the second branch line 252). , 272 can be connected. Each branch line is closed by a clamp 29 (291, 292) as a valve.
As shown in FIG. 2, the fourth line 24 may be connected to the waste tank 30.

The dialysate regeneration system 20 can further include component addition means 28 (281 to 283) for adding a desired component to the drained dialysate 52 stored in the reservoir 26. Examples of the additive component include water, carbohydrates, buffer substances such as lactic acid, acetic acid and sodium bicarbonate, and electrolytes such as sodium, calcium, magnesium and chlorine. For example, when the water removal amount in the water removal device 10 is too large and the concentration of carbohydrates or the like in the water removal completed dialysate 52 is too high, water can be added so as to be an appropriate concentration. . In addition, as a result of absorption of carbohydrates in the dialysate during peritoneal dialysis, carbohydrates can be added if the water removal ability of the dialysed fluid 52 is not sufficient.
By the component addition means, the composition of the water-retained dialysate 52 can be made closer to one suitable for dialysis.

  The dialysate regeneration system 20 can further include a priming line for priming the water remover 10 and the like. The priming line is branched from the first line 21 and is branched from the priming fluid inflow line 41 for flowing the priming solution 40 into the first compartment 11 and the second line 22 to form the first compartment 11. And a priming solution discharge line 42 for discharging the passed priming solution 40. The first line 21 and the first compartment 11 are paths through which the used dialysate 51 flows, so that the potassium and the toxin contained in the used dialysate 51 are attached to their inner surfaces. Therefore, by priming a part of the first line 21 and the first section 11 with the priming solution 40, potassium and toxin can be washed away and the effect of dialysis can be improved.

Next, a method of regenerating the dialysate using the dialysate regeneration system 20 will be described.
1. Discharge of Used Dialysate 51 in Peritoneal Cavity 90 After peritoneal dialysis is performed, the used dialysate 51 is drained from the abdominal cavity 90 through a catheter 92 placed on the abdominal wall (FIG. 2). The catheter 92 is used both when the dialysate flows into the abdominal cavity 90 and when the dialysate is discharged from the abdominal cavity 90. Therefore, two lines (first line for discharging the catheter 92 through the Y-shaped connector are used. 21 and a third line 23) for inflow are connected.
The used dialysate 51 is discharged from the first line 21 along the arrow A. At this time, by setting the water removal device 10 lower than the position of the catheter 92, the used dialysate 51 can be discharged from the abdominal cavity 90 without using a pump or the like.
The spent dialysate 51 passes through the filter 32 to filter fibrin aggregates and the like.

2. Dewatering of Used Dialysate 51 As described in detail in the first embodiment, the used dialysate 51 is continuously supplied to the first section 11 of the water remover 10 so that the used dialysate 51 is removed. A portion of the water moves through the semipermeable membrane 13 to the aqueous solution 15 in the second compartment 12 (FIG. 2, FIG. 3). In addition, when water moves, potassium and low molecular weight toxins (urea, creatinine, etc.) contained in the used dialysate 51 also move to the aqueous solution 15 through the semipermeable membrane 13.

3. Reservoir in Reservoir 26 The dialysate (that is, regenerated dialysate) 52 removed by the water remover 10 is discharged from the first section 11 of the water remover 10 to the second line 22 along the arrow 11 b. And store in reservoir 26 (FIG. 2). When all the used dialysate 51 in the abdominal cavity 90 is dewatered and stored in the reservoir 26, the dewatering process in the dehydrator 10 is completed. The obtained drained dialysate 52 is
If desired, desired components can be added from the component addition means 28 to the drained dialysate 52 in the reservoir 26.

4. Inflow of Dewatered Dialysate 52 into Peritoneal Cavity 90 The drained dialysate 52 stored in the reservoir 26 is allowed to flow into the abdominal cavity 90 through the third line 23 along arrow B (FIG. 2). At this time, by making the reservoir 26 higher than the position of the catheter 92, the drained dialysate 52 can be made to flow into the abdominal cavity 90 without using a pump or the like.

As described above, the dialysate regeneration method using the dialysate regeneration system 20 according to the present embodiment can temporarily store the dialysate regenerated in the closed circuit and then return it to the abdominal cavity 90.
In addition, the dialysate regeneration method can further include the following steps.

5. Replacement of the aqueous solution 15 When water removal of the used dialysate 51 is completed, the used aqueous solution 15b held in the second section 12 of the water removal device 10 is discharged to the fourth line 24 along the arrow 12b. To do (Figure 3). The used aqueous solution 15b is stored in the waste liquid tank 30 connected to the fourth line 24 (FIG. 2).
When all of the spent aqueous solution 15b held in the second compartment 12 has been drained, the first clamp 291 closing the first branch line 251 of the fifth line 25 is opened to The unused aqueous solution 15 a filled in the cartridge 271 is filled in the second compartment 12. The water removing device 10 filled with the unused aqueous solution 15a can be used for the next water removal treatment of the dialysate because the water removing ability is restored.

When a plurality of cartridges 27 (two in FIG. 2 and FIG. 3) are provided, the aqueous solution 15 can be exchanged twice. In the first exchange, as described above, the unused aqueous solution 15a filled in the first cartridge 271 is used. In the second exchange, the unused aqueous solution 15a filled in the second cartridge 272 is used.
The second exchange is substantially the same as the first exchange. First, the used aqueous solution 15b held in the second compartment 12 is discharged to the fourth line 24 along the arrow 12b. When all of the spent aqueous solution 15b held in the second compartment 12 has been drained, the second clamp 292 closing the second branch line 252 of the fifth line 25 is opened, and the second The unused aqueous solution 15 a filled in the cartridge 272 is filled in the second compartment 12.
As described above, by providing the plurality of cartridges 27, it is possible to perform the water removing process over multiple times without separately preparing the unused aqueous solution 15a.

6. Priming of Dialysate Regeneration System 20 Preferably, the path through which spent dialysate 51 has flowed is primed to flush away any potassium and toxins remaining on the path. The priming path through which the priming solution 40 flows is from the priming solution inflow line 41 to the priming solution discharge line 42 through the first line 21, the first section 11, the second line 22. After opening the two clamps closing the priming path (the third clamp 293 closing the priming fluid inflow line 41 and the fourth clamp 294 closing the priming fluid discharge line 42), the priming solution 40 It flows into the priming fluid inflow line 41. Alternatively, the priming solution discharge line 42 may be connected to the waste liquid tank 30, and the used priming solution 40 may be discarded to the waste liquid tank 30.

Hereinafter, materials suitable for the water removal device 10 and the dialysate regeneration system 20 according to the first and second embodiments will be described.
(Semipermeable membrane 13)
The semipermeable membrane 13 can be a membrane for dialysis of a commercially available dialyzer having a desired molecular weight cut off (for example, a molecular weight cut off in the range of 10000 to 30000) as a semipermeable membrane.
Examples of the material of the semipermeable membrane 13 include synthetic materials such as regenerated cellulose, cellulose-based materials such as cellulose triacetate, polyacrylonitrile, polymethyl methacrylate, polysulfone, polyether sulfone, ethylene vinyl alcohol copolymer, polyester-based polymer alloy, etc. Molecular systems are available.
The form of the semipermeable membrane 13 may be hollow fiber, plain weave, pleated, spiral or the like. In addition, although one hollow fiber semipermeable membrane 13 is illustrated in FIG. 1 etc., it is preferable to arrange and use many ultrafine hollow fibers in parallel.

(Aqueous solution 15)
The aqueous solution 15 used herein is an aqueous solution containing at least a polymer compound. A polymer can be used as the polymer compound.
Specific examples of suitable polymer compounds include polyethylene glycol (PEG), polyvinyl pyrrolidone (PVP), polyethylene oxide (PEO), acrylic acid polymers, polysaccharides, mucopolysaccharides, and proteins of biological origin. It is one kind. Examples of polysaccharides include carboxymethylcellulose, sucralose, hydroxypropyl cellulose, dextrin and the like. Examples of mucopolysaccharides include hyaluronic acid, chondroitin sulfate, heparin and the like. Examples of proteins of biological origin include albumin, globin, globulin and the like.
In addition, a potassium remover (sodium polystyrene sulfonate or the like) can also be added to the aqueous solution 15.

(First to fifth lines 21 to 25)
The first to fifth lines 21 to 25 are formed of a soft tube, and can be closed from the outside by a clamp or the like. As a material for the tube, for example, silicone rubber, polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP) and the like can be used.

(Priming solution 40)
As the priming solution, an aqueous solution capable of flowing a water-soluble toxin or the like can be used, and for example, physiological saline and sugar solution are preferable.

<Measurement Experiment of Water and Potassium Removal Rate by Dehydrator 10>
The removal rate of water and potassium from the used dialysate 51 was measured using a water remover 10 as shown in FIG.
30% by weight polyethylene glycol (molecular weight 20000) in the second section of the hemodialysis dialyzer (hollow fiber dialyzer KF-201 series (KF-20) manufactured by Kawasumi Chemical Co., Ltd., molecular weight cut off 11800) as the water removal device 10 A solution obtained by retaining 50 ml of an aqueous solution of 2) (addition of 2 g (4%) of caliceram-Na powder made by Sakai Pharmaceutical Industry Co., Ltd. as a potassium removal agent) was used.
Pseudo-used dialysate (model solution, below) in which 165 ml of water and 2.237 g of potassium chloride (100 mmol / L) were added to 135 ml of dialysate (Baxter, (Extra Neal Peritoneum)) as the used dialysate 51 It called "the solution for measurement". The proportion of added water (165 ml) was 55% of the total amount (135 ml + 165 ml = 300 ml) of the measurement solution used in the experiment.
The spent dialysate 51 passed through the first compartment 11 of the water cooler 10 at a flow rate of 20 ml / min.

Measure the total weight and potassium concentration for the measurement solution before flowing into the water removal device 10 (that is, before regeneration) and for the measurement solution after passing through the water removal device 10 (that is, regenerated) did. The difference of the total weight before and after water removal was divided by the weight before water removal to obtain “water removal rate (%)”. Moreover, what remove | divided the difference of the potassium concentration before and behind water removal with the potassium concentration before water removal was made "the removal rate (%) of potassium."
The measurement results are shown in FIG.

The removal rate of water was about 45% (about 135 ml), and the removal rate of potassium was about 85%. From the results of the water removal rate, it was found that water equivalent to about 82% of the water (165 ml) added at the time of preparation of the measurement solution was able to be removed. As a result, the osmotic pressure of the dialysate is increased to recover the water removal capacity of the dialysate, and a reusable regenerated dialysate is obtained.
In addition, it has been found that the removal rate of potassium is sufficiently high, and the potassium concentration can be reduced to a reusable level.

<Measurement Experiment of Water and Potassium Removal Rate by Dialysate Regeneration System 20>
The removal rate of water and potassium from the used dialysate 51 was measured using the dialysate regeneration system 20 as shown in FIG.
The water removal device 10 used the same thing as Example 1. The used dialysate 51 used the same measurement solution as in Example 1. In each of the two cartridges 271 and 272, 50 ml of an unused aqueous solution 15a for water removal was enclosed.

The first experiment (Experiment No. I) was conducted under the same conditions as in Example 1.
In the second experiment (Experiment No. II), after replacing the used aqueous solution 15b with the unused aqueous solution 15a in the first cartridge 271 (FIG. 3), the water removing experiment is performed under the same conditions as the first time. went.
In the third experiment (Experiment No. III), after replacing the used aqueous solution 15b with the unused aqueous solution 15a in the second cartridge 272, the water removal experiment was performed under the same conditions as the first time.
The calculation of the removal rate was the same as in Example 1.
The measurement results are shown in FIG.

The removal rate of water was about 50% to about 42% (150 to 126 ml), and it was found that the water corresponding to about 91 to 76% of the water (165 ml) added at the time of preparation of the measuring solution could be removed The As a result, the osmotic pressure of the dialysate is increased to recover the water removal capacity of the dialysate, and a reusable regenerated dialysate is obtained.
In addition, although the potassium removal rate varied from about 68 to 95%, it was about 80% on average, and it was found that the removal rate of potassium was sufficiently high, and the potassium concentration could be reduced to a reusable level. .

DESCRIPTION OF SYMBOLS 10 Dehumidifier 11 1st division 12 2nd division 13 semipermeable membrane 14 casing 15 aqueous solution for water removal 20 dialysate regeneration system 21, 22, 23, 24, 25 line 26 reservoir 27 cartridge 291, 292, 293 , 294 clamps 40 priming fluid 90 abdominal cavity

Claims (9)

A dewaterer for removing a portion of water from used dialysate, comprising:
A casing having a first compartment Ru was circulated spent dialysate, a second compartment spaced from said first compartment by a semipermeable membrane, a,
The held in the second compartment, said from the spent dialysate to a water solution you remove a portion of the water through the semipermeable membrane, 1.5 times or more the molecular weight cutoff of said semi-permeable membrane It is seen containing an aqueous solution for removing water containing in the polymer compound 10-30 wt% having a molecular weight, a,
The water removal machine whose molecular weight of the said high molecular compound is 20000-50000 . The fractionated molecular weight is 10,000 to 13,000,
The polymer compound according to claim 1, wherein the polymer compound is at least one selected from polyethylene glycol, polyvinyl pyrrolidone, polyethylene oxide, acrylic acid polymers, polysaccharides, mucopolysaccharides, and proteins of biological origin. Dehumidifier. The water remover according to claim 1 or 2 , wherein the aqueous solution further contains a potassium removal agent. Preparing the water removal device according to any one of claims 1 to 3 .
The used dialysate is continuously supplied to the first compartment of the water remover, and a portion of the water in the dialysate is retained through the semipermeable membrane in the second space of the water remover. Moving the aqueous solution to the aqueous solution and continuously draining the drained dialysate from the first compartment, and removing a portion of the water from the spent dialysate. The water removal method according to claim 4 , wherein a flow rate of the dialysate flowing through the first section is 10 to 30 ml / min. A dialysate regeneration system for reusing used dialysate, comprising:
The water removal device according to any one of claims 1 to 3 ,
A reservoir for storing dialysate removed by the water removal device;
A first line for causing spent dialysate that has flowed out of the dialysis area to flow into a first compartment of the water cooler casing;
A second line for flowing drained dialysate discharged from the first compartment into the reservoir;
A third line for flowing the drained dialysate from the reservoir into the dialysis area. A fourth line for discharging used aqueous solution from the second section of the casing;
A fifth line for injecting unused aqueous solution into the second compartment;
The dialysate regeneration system according to claim 6 , further comprising: one or more cartridges connected to the fifth line and filled with the unused aqueous solution. 8. The dialysate regeneration system according to claim 6 , further comprising component addition means for adding a predetermined component to the drained dialysate stored in the reservoir. A priming fluid inflow line which branches from the first line and flows the priming fluid into the first compartment;
Branched from the second line, in any one of claims 6-8, characterized in that it comprises further, a priming fluid discharge line for discharging the priming liquid that has passed through the first compartment Dialysate regeneration system as described.

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