JP6843728B2 - Sterilizer - Google Patents

Description

The present invention relates to a catheter sterilizer.

Urethral catheters are often used for urinary catheterization during surgery and absolute rest. On the other hand, the use of urethral catheters also increases the risk of patients developing urinary tract infections. For example, when a urinary tract catheter is used to monitor urine output during surgery, it is less likely that bacteria will colonize the catheter and form a biofilm because of the shorter use time. However, when a urethral catheter is used for a long period of time due to urinary retention, incontinence, etc., the possibility of recurrent urinary tract infection increases.

Therefore, a technique for reducing the occurrence of urinary tract infection has been devised by using an antibacterial coating on the inner and outer surfaces of the catheter (see Patent Document 1).

JP-A-2010-533562

However, it is difficult to sufficiently and uniformly coat the inner surface of a thin tube such as a catheter with an antibacterial material. In addition, it is difficult to continuously obtain sufficient bactericidal performance because the antibacterial material is eluted by the use of the catheter.

The present invention has been made in view of these problems, and one of its exemplary purposes is to provide a new sterilization technique for catheters.

In order to solve the above problems, the sterilizer according to an embodiment of the present invention is a sterilizer that sterilizes the liquid inside the catheter, and includes a light source that irradiates ultraviolet rays and a housing that houses the light source inside. .. The housing has a holding portion that holds the catheter so that a part of the catheter is irradiated with ultraviolet rays inside the housing, and a reflecting portion that reflects the ultraviolet rays emitted from the light source.

According to this aspect, the liquid inside the catheter can be sterilized even if a catheter that has not been specially treated is used.

A catheter that is held in the holding portion may be further provided. The catheter may be configured so that the ultraviolet transmittance of the portion of the housing to which ultraviolet rays are irradiated is 10% or more. As a result, it is not necessary to construct the entire catheter with a material having an ultraviolet transmittance of 10% or more, and an increase in the material cost of the catheter can be suppressed. The material of the catheter may be, for example, a silicone-based resin or an amorphous fluorine-based resin.

The length of the portion of the catheter that is irradiated with ultraviolet rays may be 25 to 35 mm. This provides sufficient time to kill the bacteria moving in the liquid in the catheter.

The housing may have a first housing, a second housing, and a connecting portion that connects the first housing and the second housing. The connecting portion is in a state where the second housing is open with respect to the first housing so that the holding portion is exposed, and with respect to the first housing so that the holding portion and the reflecting portion are not exposed. It may be configured so that the second housing can be in a closed state. As a result, the sterilizer can be attached to the catheter prepared in advance or the catheter in use later.

The first housing and the second housing may be configured so that the boundary of the contact portion in the closed state is in the shape of a crank. As a result, it is possible to prevent the ultraviolet rays emitted from the light source housed inside the housing from leaking to the outside.

The reflective portion may be made of aluminum or fluororesin. As a result, ultraviolet rays that are not directly applied to the catheter from the light source can be reflected by the reflecting portion to irradiate the catheter, and the utilization efficiency of the ultraviolet rays is improved and the sterilization performance is also improved.

The inside of the housing may be cylindrical or spherical. The reflective portion may be the inner wall surface of the housing. As a result, the ultraviolet rays reflected by the reflecting portion tend to go toward the central portion of the housing.

The holding portion may be arranged in the housing at a position intersecting the cylindrical or spherical central axis. The retainer may also hold the catheter along the central axis. As a result, the ultraviolet rays reflected by the reflecting portion toward the central portion of the housing are efficiently irradiated to the catheter.

The light source may emit deep ultraviolet light having a peak wavelength in the range of 200 to 280 nm. As a result, bacteria moving in the liquid in the catheter can be efficiently sterilized.

It should be noted that any combination of the above components and the conversion of the expression of the present invention between methods, devices, systems and the like are also effective as aspects of the present invention.

According to the present invention, it is possible to provide a new sterilization technique for a catheter.

It is a schematic diagram for demonstrating the infection route when using a urethral catheter. It is external drawing of the sterilizer which concerns on 1st Embodiment. It is a figure which shows the state in which the housing of the sterilizer shown in FIG. 2 is opened. It is sectional drawing of the sterilizer which concerns on 1st Embodiment. It is external drawing of the sterilizer which concerns on 2nd Embodiment. It is sectional drawing of the sterilizer which concerns on 2nd Embodiment. It is sectional drawing of the housing of the sterilizer which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted as appropriate. Further, the configuration described below is an example, and does not limit the scope of the present invention at all.

(Urinary catheter)
FIG. 1 is a schematic diagram for explaining an infection route when using a urethral catheter. As shown in FIG. 1, the urethral catheter 10 is held with one end inserted from the urethra 12 and the tip reaching the bladder 14. The other end of the urethral catheter 10 is connected to the urine storage bag 16. When using the urethral catheter 10, bacteria can enter the body by various routes. For example, when the urethral catheter 10 is inserted into the urethra 12, bacteria 18 are pushed into the bladder 14 or bacteria 18 colonized in the perineum or rectum invade. Alternatively, the bacteria 18 may invade from the connection portion 13 that connects the other end 10a of the urethral catheter 10 to the urine storage bag 16 or the drainage port 16a of the urine storage bag 16 and reach the bladder 14 via urine.

In particular, if the urethral catheter 10 is used for a long period of time, the possibility that the bacteria 18 that have invaded from the connection portion or the drainage port 16a of the urine storage bag 16 reach the bladder 14 via urine increases. Therefore, the inventor of the present application has come up with the idea of preventing urinary tract infection by attaching a sterilizing device in the middle of the path of the urethral catheter 10.

(Sterilizer)
[First Embodiment]
FIG. 2 is an external view of the sterilizer according to the first embodiment. FIG. 3 is a diagram showing a state in which the housing of the sterilizer shown in FIG. 2 is opened. FIG. 4 is a cross-sectional view of the sterilizer according to the first embodiment.

The sterilizer 100 according to the first embodiment sterilizes the liquid (urine) inside the urethral catheter 10. The sterilizer 100 includes a light source 20 that irradiates ultraviolet rays, and a housing 22 that houses the light source 20 inside. The housing 22 has a holding portion 24 that holds the urethral catheter 10 so that a part of the urethral catheter 10 is irradiated with ultraviolet rays inside the housing, and a reflecting portion 26 that reflects the ultraviolet rays emitted from the light source 20. ..

As a result, the liquid inside the catheter can be sterilized even if the urethral catheter 10 which has not been subjected to a special treatment (for example, antibacterial treatment) is used.

Further, the urethral catheter 10 is configured such that the ultraviolet transmittance of the portion 10b irradiated with ultraviolet rays inside the housing 22a is 10% or more. The material of the urethral catheter 10 may be, for example, a silicone-based resin or an amorphous fluorine-based resin. As a result, it is not necessary to construct the entire urethral catheter 10 with a material having an ultraviolet transmittance of 10% or more, and an increase in the material cost of the catheter can be suppressed.

The length L of the portion of the urethral catheter 10 that is irradiated with ultraviolet rays inside the housing 22a is 10 to 50 mm, preferably 15 to 40 mm, and more preferably 25 to 35 mm. As a result, sufficient time can be secured to kill the bacteria moving in the liquid in the urethral catheter 10.

The housing 22 has a cylindrical shape inside, and the height of the internal space is 10 to 55 mm, preferably 15 to 45 mm, and more preferably 25 to 40 mm. The radius of the internal space of the housing 22 is 10 to 30 mm, preferably 10 to 25 mm, and more preferably 15 to 20 mm. The holding portion 24 is arranged at a position where it intersects with the central axis X of the housing 22. Further, the holding portion 24 holds the urethral catheter 10 along the central axis X.

The reflective portion 26 constituting the inner surface (inner wall surface) of the housing 22 is coated with aluminum, which is a metal film, and has a reflectance of about 90% for ultraviolet rays having a peak wavelength of 270 nm, which is deep ultraviolet rays. By forming the housing 22 itself with aluminum, which is the same material as the reflective portion 26, it is not necessary to coat the housing 22 with aluminum, and the heat dissipation property is also improved. Aluminum is suitable as a material for the reflective portion 26 from the viewpoint of cost, weight, and heat dissipation, but a fluororesin such as PTFE may be used as the material for the reflective portion 26 from the viewpoint of ultraviolet resistance.

Further, when a plurality of LEDs are dispersedly arranged as a light source 20 on the inner surface of the cylinder and the ultraviolet rays are irradiated toward the center, the ultraviolet rays hit the inner surface of the cylinder and repeat reflection with attenuation of about 10%. As a result, ultraviolet rays, which are about 10 times the original light output, effectively fly in the cylindrical space.

Further, since the housing 22 has a cylindrical shape, the ultraviolet rays reflected by the reflecting portion 26 tend to go toward the central portion of the housing 22. That is, the ultraviolet rays reflected by the reflecting portion 26 toward the central portion of the housing 22 are efficiently irradiated to the urethral catheter 10. As a result, the ultraviolet rays that were not directly irradiated to the urinary tract catheter 10 from the light source 20 can be reflected by the reflecting portion 26 to irradiate the urinary tract catheter 10, and the utilization efficiency of the ultraviolet rays is improved and the sterilization performance is also improved. ..

When the light output of the LED is 10 mW, when the catheter arranged in the center of the cylinder is irradiated with light (ultraviolet rays), an illuminance of about 1 mW / cm ² or more can be obtained on the surface of the catheter. The urethral catheter 10 is mainly made of a silicone-based resin, and is made of a material that does not use a component that absorbs ultraviolet rays as much as possible. The urethral catheter 10 according to the present embodiment has a wall thickness of about 1 mm and a transmittance of ultraviolet rays having a peak wavelength of 270 nm of 10% / mm.

That is, the liquid inside the catheter is irradiated with ultraviolet rays having an ^{illuminance of 0.1 mW / cm 2.} Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, etc. can be expected to have a bactericidal effect of about 99.9% when irradiated with ultraviolet rays ^{of about 10 to 20 mJ / cm 2.} That is, the liquid can be sterilized by exposing it to ultraviolet rays in the urethral catheter 10 for 200 seconds (about 3.3 minutes).

Next, the moving speed of the bacteria in the catheter will be described. The mean free path in a liquid having a viscosity such as water is about 10 pm, and the diffusion coefficient in the liquid is about ^10-9 m ² / s. If the distance between the place where the bacteria can enter the catheter and the urethra is 10 cm, it will take 8 months for the bacteria to reach the urethra by diffusion. In other words, if the movement of bacteria is due to diffusion in a liquid, infectious diseases to humans will not occur much. Therefore, it is presumed that the movement of bacteria in the catheter is due to convection of liquid or flow when the catheter is physically moved, rather than diffusion.

Statistically, it has been reported that wearing a urethral catheter for 7 to 10 days causes infection in half of them. From this result, the migration rate of bacteria is roughly estimated. If the catheter length is 3 m and the bacteria regurgitate in one day, which is shorter than 7 days, the migration speed of the bacteria is 3 m / 24 hours = 2.1 mm / min. When the height of the cylindrical housing of the present embodiment is 30 mm, it takes about 14 minutes at 30 mm ÷ 2.1 mm to pass through the housing. As described above, when the light output of the LED is 10 mW, the bacteria are considered to be almost annihilated because they receive ultraviolet rays ^{of about 85 mJ / cm 2 while passing through the housing.} Further, considering that it is sufficient to receive the irradiation of ultraviolet rays of 10 to ²⁰ mJ / cm 2 in about 14 minutes, the light output of the LED is sufficient to be about 2 mW.

Next, the structure of the housing will be described. As shown in FIGS. 2 and 3, the housing 22 according to the present embodiment includes a first housing 28a, a second housing 28b, a first housing 28a, and a second housing 28b. It has a connecting portion 30 and a connecting portion 30 for connecting the above. In the connecting portion 30, the holding portion 24 and the reflecting portion 26 are not exposed when the second housing 28b is open with respect to the first housing 28a (FIG. 3) so that the holding portion 24 is exposed. The second housing 28b is closed to the first housing 28a (FIG. 2). As a result, the urethral catheter 10 is placed on the holding portion 24 in the state of FIG. 3, and the first housing 28a and the second housing 28b are closed, so that the catheter prepared in advance or the catheter in use can be used. On the other hand, the sterilizer 100 can be attached later.

Further, the housing 22 may be provided with a fin structure on the outer surface. As a result, the surface area on the outside of the housing 22 is increased, and the heat generated by the light source 20 can be efficiently released to the outside.

[Second Embodiment]
FIG. 5 is an external view of the sterilizer according to the second embodiment. FIG. 6 is a cross-sectional view of the sterilizer according to the second embodiment. FIG. 7 is a cross-sectional view of the housing of the sterilizer according to the second embodiment.

The main difference of the sterilizer 110 according to the second embodiment is that the shape of the housing is spherical as compared with the sterilizer 100 according to the first embodiment. The sterilizer 110 has a spherical housing 32 and a urethral catheter 10 provided so as to penetrate the housing 32. The housing 32 has a hemispherical first housing 34a and a hemispherical second housing 34b.

A plurality of light sources 20 are provided on the inner surfaces of the first housing 34a and the second housing 34b. Each light source 20 is arranged so that the light emitting surface faces the urethral catheter 10. In this way, by making the inner surface shape of the housing 32 spherical, the ultraviolet rays reflected by the reflecting portion 26 can easily go toward the central portion of the housing 32. That is, the urethral catheter 10 can be efficiently irradiated with ultraviolet rays.

Further, in the vicinity of the upper and lower openings through which the urethral catheter 10 of the housing 32 penetrates, a shielding mask 36 is provided to prevent a gap so that the light of the light source 20 does not leak to the outside. The shielding mask 36 is, for example, a flexible elastic member (rubber or plastic having ultraviolet resistance resistance), a metal member having a bellows structure, a movable member such as a lens diaphragm structure, or the like. In the present embodiment, the shielding mask 36 also functions as a holding portion.

Further, the ultraviolet rays emitted from the light source 20 inside the housing 32 may leak from the contact portion between the first housing 34a and the second housing 34b. Therefore, as shown in FIG. 7, the first housing 34a and the second housing 34b according to the second embodiment are configured so that the boundary of the contact portion 38 in the closed state is a crank shape. Has been done. The boundary of the contact portion is preferably not a straight line (flat surface), and may be a curved surface (curved surface) or an uneven surface. As a result, it is possible to prevent the ultraviolet rays emitted from the light source 20 housed inside the housing 32 from leaking to the outside.

The peak wavelength of ultraviolet rays emitted by the LED used for the light source 20 according to each of the above-described embodiments is in the range of 200 to 400 nm, preferably in the range of 200 to 350 nm, and more preferably in the range of 200 to 280 nm. Range (deep UV wavelength). In particular, deep ultraviolet rays can efficiently sterilize bacteria moving in the liquid in the catheter.

As described above, the sterilizer according to each embodiment can be additionally attached to a normal urethral catheter and turn on an LED that emits ultraviolet rays to sterilize bacteria (miscellaneous bacteria) flowing back in the urethral catheter. As a result, nosocomial infections can be prevented and the urethral catheter can be used for a long period of time. In addition, the patient also has the advantage of reducing the number of painful catheter insertions and maneuvers. It is also effective in controlling medical expenses.

Although the present invention has been described above with reference to the above-described embodiments, the present invention is not limited to the above-described embodiments, and the configurations of the embodiments are appropriately combined or substituted. Those are also included in the present invention. Further, it is also possible to appropriately rearrange the combinations and the order of processing in the embodiments based on the knowledge of those skilled in the art, and to add modifications such as various design changes to each embodiment. Additional embodiments may also be included in the scope of the present invention.

10 Urethral catheter, 10a other end, 12 urethra, 14 bladder, 16 urine storage bag, 16a drainage port, 18 bacteria, 20 light source, 22 housing, 22a housing inside, 24 holding part, 26 reflex part, 28a first Housing, 28b second housing, 30 connecting part, 32 housing, 34a first housing, 34b second housing, 36 shielding mask, 38 contact part, 100, 110 sterilizer.

Claims (6)

A sterilizer that sterilizes the liquid inside the catheter.
Multiple LEDs that irradiate ultraviolet rays,
A housing in which the plurality of LEDs are arranged on the inner side surface, and the like.
The housing is
A holding portion that holds the catheter so that a part of the catheter is irradiated with the ultraviolet rays inside the housing.
A reflective unit that reflects ultraviolet rays emitted from the plurality of LEDs,
Have a, a catheter is held in the holding portion,
The catheter has a length of a portion irradiated with ultraviolet rays inside the housing of 25 to 35 mm.
The reflective portion is made of aluminum or fluororesin, and is made of aluminum or fluororesin.
The inside of the housing is cylindrical and has a cylindrical shape.
The reflecting portion, sterilizing apparatus, wherein an inner wall surface der Rukoto of the housing. The sterilizer according to claim 1, wherein the catheter is configured such that the ultraviolet transmittance of a portion irradiated with ultraviolet rays inside the housing is 10% or more. The housing has a first housing, a second housing, and a connecting portion for connecting the first housing and the second housing.
In the connecting portion, the second housing is open with respect to the first housing so that the holding portion is exposed, and the holding portion and the reflecting portion are not exposed. The sterilizer according to claim 1 or 2 , wherein the second housing is closed with respect to the housing of 1. The sterilizer according to claim 3 , wherein the first housing and the second housing are configured so that the boundary of the contact portion in the closed state is in the shape of a crank. The holding portion is a position intersecting the cylindrical central axis of the arranged casing, to any one of claims 1 to 4, characterized in that to hold the catheter along said central axis The sterilizer described. The sterilizer according to any one of claims 1 to 5 , wherein the LED emits deep ultraviolet rays having a peak wavelength in the range of 200 to 280 nm.

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