JPH027665B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a sterilization method for killing microorganisms attached to equipment that is required to be sterile during medical treatment, and more particularly to a sterilization method for killing microorganisms by heat. Medical instruments and materials are required to be sterile before use, and are sterilized before use, and methods include radiation sterilization, drug sterilization, and heat sterilization. Among these, radiation sterilization and gas sterilization are suitable methods for disposable instruments and materials and are widely adopted, but they are difficult to apply to items that need to be sterilized after each repeated use, and are particularly difficult to apply. It is not suitable for personal use because the equipment is large-scale. Therefore, equipment that requires sterilization each time it is used, such as for dialysis, infusion, and blood transfusion, is usually sterilized with a chemical solution. However, disinfection using chemical solutions has various problems such as the existence of bacteria resistant to the chemical solution used, the coexistence of organic substances that reduce the sterilizing effect, and even side effects on the human body, so it is not a strict sterilization method. . This point will be explained in more detail. Peritoneal dialysis treatment, which has been attracting attention recently, does not cause adhesions, the device is simpler than artificial kidneys, the treatment cost is significantly lower, the burden on the patient is greatly reduced, and it is a continuous continuous ambulatory system. When peritoneal dialysis came into general use, it became possible to work while continuing treatment, but what supported the reliability of this dialysis method was the prevention of bacteria entering the dialysis tube. The question is whether it is possible to avoid the proliferation of microorganisms within the peritoneal cavity and the complications of peritonitis. Since the abdominal cavity has no ability to defend against bacteria, the absolute challenge of this type of technology is to reliably prevent the invasion of bacteria, but disinfection using chemical solutions is extremely inadequate in this respect. . Heat sterilization methods have been considered in recent years as a solution to these problems, but steam sterilization, like radiation sterilization, has the disadvantage of requiring large-scale equipment, and flame sterilization, such as alcohol lamps, can cause burns and other problems. It has the disadvantage that it poses a risk of fire and cannot be sterilized reliably without a certain level of skill. The object of the present invention is to solve the above-mentioned drawbacks, to provide a simple device that can be used by an individual patient, with little risk in use, and capable of repeatedly sterilizing an instrument to be sterilized, which is a medical tube connector.
Its sterilization effect is to provide a sterilization method that is reliable and complete. In order to achieve the above object, the present invention provides a novel heat sterilization method in which a medical tube connector, at least a portion of which is formed of a conductor, is placed in an induced magnetic field of a high-frequency current. This invention presents a method for sterilizing medical tube connectors, which is characterized by heating to a temperature exceeding 200°C to kill attached microorganisms. To further explain the present invention, high-frequency induction heating is when a certain type of conductor is placed in a magnetic field caused by a high-frequency induced current, eddy currents are generated on the surface of the conductor, and the current loss is converted into thermal energy. It utilizes the principle that the conductor itself rises to a high temperature when converted to a high temperature. In the present invention, it is preferable that at least a portion of the medical tube connector to be sterilized is formed of this type of conductor. However, even if the equipment to be sterilized is not made of a conductor, if a means for bringing the conductor into contact with or close to the equipment to be sterilized is provided around or near the equipment to be sterilized, the equipment can be heated indirectly, so the present invention is applicable. can. In addition, by applying this technique and forming only the necessary parts of the equipment with that kind of conductor, it is also possible to selectively heat only the parts that need to be sterilized. The conductor is preferably iron, nickel, cobalt, or an alloy containing these, and preferably has excellent high-temperature oxidation deterioration resistance. In order to complete sterilization, the equipment to be sterilized must be kept at a temperature of 200°C or higher for a certain period of time, and to satisfy this heating condition, it is considered appropriate that the magnetic flux density of the high-frequency magnetic field is approximately 10 Gauss or higher. . Of course, this value depends on the material, shape, dimensions, etc. of the equipment, and therefore does not specify the content of the present invention. Hereinafter, an apparatus for implementing the present invention will be explained in detail with reference to the drawings. FIG. 1 is a perspective view showing an example of a sterilization apparatus for carrying out the method of the present invention. In the figure, the sterilizer is comprised of a high frequency current generating means 1, a coil 2, and a sterilization chamber 3. High frequency current generation means 1
may be one for a known high-frequency induction heating device,
Select according to sterilization temperature and sterilization time. The coil 2 is connected to the output terminal of the high-frequency current generating means 1, and is wound around the wall of the sterilization chamber 3 based on an inductance calculation corresponding to a desired number of magnetic fluxes. The sterilization chamber 3 has a hollow cylindrical shape with at least one end open, and is made of a non-conductive heat-resistant material such as ceramic or heat-resistant plastic.
An instrument to be sterilized, which is a medical tube connector, is set in the hollow cylinder and sterilized. Note that the sterilization chamber may be arranged around the coil instead of at the heat generating part within the coil, but this results in a large loss in terms of thermal efficiency. Next, an example of sterilization performed using the above sterilization device will be described. Example 1 The output settings of the high-frequency current generating means and the coil were set to 135 watts of power, 10 kilohertz frequency, and 500 gauss maximum magnetic flux density. The equipment to be sterilized was a tube connector made of ferrite stainless steel that is actually used for peritoneal perfusion. FIG. 2A is a perspective view of the connector used in the experiment, and FIG. 2B is a sectional view of the same connector. Attach 10 ⁵ indicator bacteria to the inside of this tube connector to confirm the sterilization ability, set this tube connector in the sterilization chamber, and measure the time required for all the indicator bacteria to die. A comparison was made with flame sterilization and chemical disinfection using an isodine stock solution. In addition, as indicator bacteria, spores of B. stearothermophillus, which has the highest resistance to heat, are used.
and B as the most resistant bacteria to drugs.
Two types of S. subtilis spores were used. The results of the experiment are shown in the table.

[Table] As is clear from this table, the effect of high-frequency induction heating sterilization according to the present invention is faster and more reliable than flame sterilization or chemical disinfection. Moreover, unlike flame sterilization, there is no risk of fire or burns, and it is simple and easy to handle by individual patients, and both the sterilizer and the equipment to be sterilized can be used repeatedly. For repeated use, it is convenient to attach a timer mechanism to the high frequency current generating means 1 shown in FIG. Furthermore,
As already mentioned, parts that require sterilization can be selectively and efficiently sterilized by forming them with conductors, so even parts that cannot be structurally sterilized with flame sterilization or chemical disinfection can be easily and reliably sterilized. Can be sterilized. Such a sterilization method is useful for tube connectors for blood transfusions, infusions, dialysis, etc., and is particularly useful for sterilizing tube connectors for peritoneal dialysis. As explained above, the present invention employs a sterilization method that uses high-frequency induction heating to heat a medical tube connector, which is an instrument to be sterilized, to a temperature exceeding 200°C. In addition, medical tube connectors generally have a complicated shape, and other heating methods require longer heating times to sterilize the inside. According to this method, since the entire surface can be heated uniformly, it is possible to achieve reliable sterilization in a short time.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an example of a sterilization apparatus for carrying out the method of the present invention, FIG. 2A is a perspective view of a part of an instrument to be sterilized, and FIG. 2B is a sectional view of the same instrument. 1... High frequency current generating means, 2... Coil, 3
...Sterilization room.

Claims (1)

[Claims] 1 Place a medical tube connector, at least a portion of which is made of a conductor, in the induced magnetic field of a high-frequency current, and heat the medical tube connector to 200°C.
A method for sterilizing medical tube connectors, which comprises heating to a temperature exceeding 100 mL to kill attached microorganisms.