JPH07275354A - Drug dissolving device - Google Patents

Abstract

PURPOSE:To provide a device which automatically makes medical fluid for a blood dialyser from powder drug using an electrical conductivity meter as a detector for the concentration of solution. CONSTITUTION:Powder drug is supplied from a dissolving water and drug A supplier 3 to a dissolving section 4, the temperature of solution is maintained at above 20 deg.C with a heater 2, the concentration of the solution is continuously detected by a concentration detector 1, the supplying amount of the powder drug is controlled, and a specified concentration of medical fluid is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug dissolving device for easily and efficiently preparing a drug solution to be supplied to a blood transfusion device used for treating renal failure or the like.

[0002]

2. Description of the Related Art Sodium chloride type solutions (hereinafter referred to as solution A) and sodium bicarbonate type solutions (hereinafter referred to as solution B) are used as hemodialysis chemicals. These solutions have a concentration difference of ± 1 with respect to a given concentration due to therapeutic needs.
It is managed to about%. Solution A is usually prepared by diluting stock solution A (concentrated solution of agent A) and solution B is prepared by diluting solution B (mainly concentrated solution of sodium bicarbonate), but these stock solutions must be properly controlled in concentration. Since it has to be prepared, it is prepared by a drug manufacturer and sold as 10 liter containers for both A stock solution and B stock solution. To supply the drug solution to the hemodialysis machine, (a) Purchase both the A stock solution and the B stock solution from the drug manufacturer. (B) A stock solution is purchased from a chemical manufacturer. The stock solution B is filled with water for dissolution in a large-capacity tank of about 200 liters, and while being stirred by a stirrer, manually sampled and measured the concentration by an osmometer, and is a powdered drug containing sodium bicarbonate as a main component (hereinafter referred to as agent B (Referred to as “)” is adjusted to prepare a stock solution B having a predetermined concentration. Supplying these stock solutions to the hemodialysis machine is done by a qualified person.

[0003]

5 liters of A stock solution and 5 B stock solution are required for hemodialysis for one person. Therefore, the amount of A stock solution and B stock solution purchased from a drug manufacturer in a 10-liter container is equivalent to two people. Demand for hemodialysis is extremely high, and the amount of drug solution used is enormous. Not only does A stock solution (and B stock solution in the case of (a) above) be purchased in large quantities, but it is also used to supply the drug solution to the hemodialysis machine. It takes a lot of effort. As described above, in the conventional chemical solution supply to the hemodialysis device, labor saving and efficiency improvement are indispensable in order to meet the increasing demand for dialysis.

[0004]

The structure of the present invention will be described. (A) Means for supplying dissolution water (reverse osmosis membrane filtered water, etc.) is provided. (B) Provide a solution concentration detection unit using an electric conductivity meter. (C) A heating unit for heating the water or solution for dissolution is provided. (D) An A-agent supply unit that can control the supply amount of the powdered medicine is provided. (E) A dissolving part for the powdered medicine is provided. (F) Provide a chemical solution outlet. It is configured as described above.

[0005]

Next, the operation of the present invention will be described. The preparation of the drug solution is
Basically, the water for dissolution is put in a dissolution tank or the like, and the powdered medicine is supplied and dissolved therein, and the solution concentration is adjusted. The drug dissolution apparatus according to the present invention, in order to perform these operations automatically and continuously, introduces water for dissolution into the dissolution section and adjusts the solution concentration to a predetermined concentration, while detecting the solution concentration, It operates so as to control the supply amount of the powdered medicine and supply it to the dissolution section. The principle of detecting the solution concentration by the electric conductivity meter used as the solution concentration detecting means utilizes that the electric conductivity varies depending on the solution concentration. The relationship between the electrical conductivity and the solution concentration depends on the substance dissolved in the solution, but the solution of the above-mentioned agent A will be described as an example. The electric conductivity of the solution of the agent A is almost the same as the electric conductivity of the sodium chloride solution which is the main component. Further, this electric conductivity varies depending on the solution temperature. FIG. 1 is a graph showing the electric conductivity with respect to the concentration of the sodium chloride solution for each temperature (from Umejiro Yoshida, Yokohama National University, electron and chemical measurement). The vertical axis represents the electric conductivity, the horizontal axis represents the solution concentration in weight%, and the relationship is represented as a curve for each temperature. It can be seen from FIG. 1 that the higher the solution temperature, the greater the change in the electrical conductivity with respect to the change in the concentration of the solution. This shows that the higher the solution temperature, the higher the sensitivity of the solution concentration detection by the electric conductivity meter, and the minute difference in the solution concentration can be detected as a change in the electric conductivity. This is a condition necessary for accurately adjusting the concentration of the drug solution. In order to increase the solution concentration detection sensitivity of the electric conductivity meter, it is necessary to raise the temperature of the solution in the dissolution section.The solution temperature must be raised by heating the water for dissolution or by heating the solution in the dissolution section. Appropriate temperature range (for example, 20 ℃ or higher)
Try to keep In this way, by providing a means capable of detecting a minute difference in the solution concentration and controlling the supply amount of the powdered drug so that the solution has a predetermined solution concentration, it is possible to prepare a drug solution having a high concentration accuracy. Instead of controlling the supply amount of the powder drug, it is possible to control the supply amount of the dissolving water or both.

[0006]

EXAMPLES Examples of the present invention will be described. FIG. 2 is a block diagram of one embodiment of the present invention. In the embodiment shown in FIG. 2, the dissolution water is heated in the heating unit, for example, to about 30 ° C. and supplied to the dissolution unit, and the concentration detection unit detects the concentration of the solution,
This is an example in which the supply amount of the agent A is controlled to prepare the solution A (or the stock solution A) having a predetermined concentration. FIG. 3 is a flow chart of another embodiment of the present invention. In the embodiment of FIG. 3, the solution in the dissolution section is continuously circulated through the heating section, and the agent A is dissolved while being heated to, for example, about 25 ° C. As in the embodiment shown in FIG. This is an example of controlling the supply amount of the agent A while detecting the concentration to prepare the solution A (or the stock solution A) having a predetermined concentration.

[0007]

EFFECT OF THE INVENTION When the solution A (or stock solution A) is prepared by the drug dissolving apparatus of the present invention, the difference in solution concentration is within ± 1%,
Solution concentration difference when the solution (or B stock solution) was prepared is ± 0.7
It can be about%. Further, by using the drug dissolving device according to the present invention, it is possible to continuously prepare a drug solution, and the preparation capacity is increased.

[Brief description of drawings]

FIG. 1 is a graph showing the electric conductivity with respect to the concentration of a sodium chloride solution.

FIG. 2 is a block diagram of an embodiment of the present invention.

FIG. 3 is a flowchart of another embodiment of the present invention.

[Explanation of symbols]

 1 Concentration detection part 2 Heating part 3 A agent supply part 4 Melting part 5 Supply amount control valve 6 Open / close valve 7 Liquid feed pump 8 Electrical conductivity detector 9 Chemical liquid take-out valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiro Yuma, 613 Kitairizo, Sayama City, Saitama Prefecture Toa Denwa Kogyo Co., Ltd. Sayama Plant (72) Hiroyuki Suzuki, 613 Kitaiso, Sayama City, Saitama Prefecture Toa Denwa Kogyo Co., Ltd. Sayama Plant (72) Inventor Toshiyuki Naka, 613 Kitairizo, Sayama City, Saitama Prefecture Toa Denwa Kogyo Co., Ltd. Sayama Plant

Claims (1)

[Claims] 1. When a hemodialysis drug solution is prepared, a predetermined amount is controlled by controlling the supply amount of the agent A in the step of dissolving a powdered drug containing sodium chloride as a main component (hereinafter referred to as agent A) in water for dissolution. A drug dissolving device characterized in that an electric conductivity meter is used as a solution concentration detecting means to adjust the solution concentration, and the solution temperature is kept at 20 ° C. or higher.