JP2020081745A - Sterilizer - Google Patents

Abstract

To provide a sterilizer capable of sterilizing a wide range of a needleless connector.SOLUTION: A sterilizer has a light source for emitting UV light, and a reflection part having a reflection surface constituted so that the inner diameter is enlarged gradually in proportion to the degree of separation from the light source, for reflecting UV light emitted from the light source toward the needleless connector.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sterilizer for sterilizing a needleless connector.

BACKGROUND ART In modern medical care, it is one of the leading health care methods to deliver drugs and nutritional supplements intravenously using an IV catheter. At present, nosocomial infection caused by this catheter has become a major problem in the medical field, and it is called catheter-related bloodstream infection (CR-BSI). At present, such catheter-related bloodstream infections propagate Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus aureus, Escherichia coli, etc. present in the skin of the hospital and the human body, and these bacteria invade the human body through the catheter. It is known that this is caused and caused.

In the IV catheter administration set, a needleless connector is generally used to connect between the male luer on the liquid side and the indwelling catheter on the human body side. It is known that about half of them originate from this needleless connector. Specifically, the above bacteria or viruses adhere to the surface or inside of the needleless connector to form colonies called biofilms over time, and the bacteria enter the human body through the catheter from these colonies. Is believed to cause infections.

As a procedure for operating the catheter to prevent such infectious diseases, when exchanging the infusion container containing the infusion solution flowing through the catheter, the male luer on the drug solution side is connected to the needleless connector placed on the human body side. It has been widely practiced to wipe off the affected portion with absorbent cotton containing an organic solvent having a bactericidal action such as ethanol, IPA or chlorohexidine for about 15 to 30 seconds. It has also been found that this procedure can reduce infections to some extent.

However, this procedure is a burden because it takes a lot of time and labor in the medical field, and in addition to the fact that the wiping time and the wiping strength vary from person to person, this procedure is not always performed in the medical field. Exists.

As an invention for solving the problem of infectious diseases caused by such a needleless connector, there is one that attempts to positively utilize the bactericidal action of ultraviolet light (see, for example, Patent Document 1).

The UV sterilization system described in Patent Document 1 has a housing including a UV light source and a shield including an internal reflection surface. The shield is held in the receptacle of the housing. When ultraviolet light is emitted from the UV light source with a part of the needleless connector inside the shield, part of the surface of the needleless connector is sterilized by the ultraviolet light.

Japanese Patent Publication No. 2015-528709

However, the invention described in Patent Document 1 has a problem that only part of the surface of the needleless connector can be sterilized.

The present invention has been made in view of the above points, and an object of the present invention is to provide a sterilizing device capable of sterilizing a wide range of a needleless connector.

The sterilizer according to the present invention is a sterilizer for sterilizing a needleless connector, and has a light source that emits ultraviolet light, and a reflecting surface that is configured so that the inner diameter increases as the distance from the light source increases. A reflecting portion for reflecting the ultraviolet light emitted from the light source toward the needleless connector.

ADVANTAGE OF THE INVENTION According to this invention, the sterilizer which can sterilize the wide range of a needleless connector can be provided. Therefore, according to the present invention, the occurrence of catheter-related bloodstream infections can be reduced.

FIG. 1A is a diagram showing a sterilizer according to an embodiment of the present invention and a needleless connector that is sterilized by the sterilizer. FIG. 1B is a diagram showing a state when the needleless connector is being sterilized by the sterilizing apparatus. FIG. 2 is a diagram showing a compound parabolic concentrator. FIG. 3A is a diagram showing a part of the cross section of the sleeve of the needleless connector used for the simulation on the ZY plane. FIG. 3B is a view showing the outer appearance of the sleeve. FIG. 3C is a graph showing an ultraviolet light transmittance spectrum of silicone used in the simulation. FIG. 4A is a diagram showing a part of the cross section of the housing of the needleless connector used for the simulation on the ZY plane. FIG. 4B is a view showing the outer appearance of the housing. FIG. 4C is a graph showing an ultraviolet light transmittance spectrum of the resin used for the simulation. FIG. 5A is a diagram showing an optical model of a comparative example used in the simulation. FIG. 5B is a diagram showing the optical model 1 of the example used for the simulation. 6A, 6B, and 6C are graphs showing the illuminance distribution of the optical model of the comparative example shown in FIG. 5A. 6D, E, and F are graphs showing the illuminance distribution of the optical model 1 of the embodiment shown in FIG. 5B. FIG. 7 is a diagram showing the optical model 2 of the example used for the simulation. FIG. 8 is a graph showing the illuminance distribution of the optical model 2 of the embodiment shown in FIG. FIG. 9 is a diagram showing the optical model 3 of the example used for the simulation. 10A, 10B, and 10C are graphs showing the illuminance distribution of the optical model 3 of the embodiment shown in FIG. FIG. 11 is a diagram showing the optical model 4 of the example used for the simulation. FIG. 12 is a graph showing the illuminance distribution of the optical model 4 of the embodiment shown in FIG. FIG. 13 is a diagram showing the optical model 5 of the example used for the simulation. FIG. 14 is a graph showing the illuminance distribution of the optical model 5 of the embodiment shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Structure of sterilizer)
1A and 1B are cross-sectional views showing the configuration of a sterilization apparatus 100 according to an embodiment of the present invention. FIG. 1A shows a state before arranging the needleless connector 200 inside the reflection section 120, and FIG. 1B shows a state after arranging the needleless connector 200 inside the reflection section 120.

As shown in FIGS. 1A and 1B, the sterilizer 100 includes a light source 110 that emits ultraviolet light 111 and a reflector 120 that reflects the ultraviolet light 111 emitted from the light source 110 toward the needleless connector 200. Have.

The light source 110 emits ultraviolet light 111 for sterilizing the needleless connector 200. The type of the light source 110 is not particularly limited as long as it can emit the ultraviolet light 111. Examples of the light source 110 include a semiconductor laser and a light emitting diode. From the viewpoint of enhancing the bactericidal effect, the light source 110 is preferably a light source that can emit deep ultraviolet light having a wavelength of 200 to 300 nm. Examples of the light source capable of emitting deep ultraviolet light include a light emitting diode having a center wavelength of 265 nm or 285 nm. The light source 110 may be arranged inside the reflection part 120 or may be arranged outside. In addition, the light source 110 may be arranged, for example, on the top 121 of the reflecting section 120. In addition, the light source 110 may be disposed inside the reflecting section 120, which is separated from the top 121 of the reflecting section 120 by 2 to 10 mm, for example.

The reflecting section 120 has a reflecting surface 123 configured such that the inner diameter thereof increases as the distance from the light source 110 increases, and reflects at least a part of the ultraviolet light 111 emitted from the light source 110 toward the needleless connector 200. The structure of the reflection part 120 is not particularly limited as long as the above function can be exhibited. The reflection part 120 may be configured to surround the entire needleless connector 200, or may be configured to surround a part thereof.

The reflection surface 123 preferably includes a radiation surface from the viewpoint of efficiently reflecting the ultraviolet light 111 emitted from the light source 110 to the needleless connector 200. The structure of the reflecting surface 123 is not particularly limited as long as it can reflect the ultraviolet light 111, and is, for example, the surface of an aluminum layer. Specifically, for example, the reflection unit 120 is an aluminum mirror or the like.

The reflecting unit 120 is preferably a compound parabolic concentrator from the viewpoint of efficiently reflecting the ultraviolet light 111 emitted from the light source 110 to the needleless connector 200. Here, a compound parabolic concentrator (CPC) is an optics that is often used in non-imaging optics such as solar power generation and that collects light incident from a predetermined angle range. It is a part. In general, the compound parabolic concentrator is often used for condensing the light incident from the end portion having the larger inner diameter. On the other hand, in the present embodiment, the compound parabolic concentrator is used for condensing the light emitted from the vicinity of the end on the side with the smaller inner diameter.

FIG. 2 shows an example of the appearance of the compound parabolic concentrator. The reflector 120 shown in FIG. 1 is a hollow member, but the compound parabolic concentrator shown in FIG. 2 is a solid member made of a light transmissive material. In typical usage, the left end is the light entrance and the right end is the light exit. The reflective surface that connects them is a parabolic surface. In a solid compound parabolic concentrator, the reflective surface is configured to produce total internal reflection. The parameters that determine the structure and performance of the compound parabolic concentrator are the light entrance radius a _in , the light exit radius a _out, and the overall length L.

Further, the refractive index of a medium constituting the compound parabolic concentrator, where the n _i, the refractive index of the medium outside of the compound parabolic concentrator and n _out, the light incident from the inlet When the angle range to be incident is θ _i and the emission angle of the light emitted from the outlet is θ _out , the length L and the light collection efficiency C of the compound parabolic concentrator are expressed by the following equations. ..

L=(a _in +a _out )/tan θ _i (Equation 1)
C=[n _out sin θ _out /n _i sin θ _i ] (Equation 2)

The compound parabolic concentrator may have a hollow structure as shown in FIG. 1 in consideration of cost. Such a compound parabolic concentrator is sometimes called a parabolic mirror.

Although not shown in FIGS. 1A and 1B, the sterilization device 100 may have a positioning portion for disposing the needleless connector 200 at an appropriate position. The configuration of the positioning portion is not particularly limited as long as the needleless connector 200 can be arranged at an appropriate position inside and outside the reflecting portion 120, but is arranged between the reflecting portion 120 and the needleless connector 200, for example. When the sterilization device 100 has a positioning part, the positioning part arranges the needless connector 200 at an appropriate position in the sterilization device 100 and prevents the reflection part 120 and the needleless connector 200 from coming into contact with each other. It is possible to prevent the reflection part 120, which may be

The configuration of the needleless connector 200 to be sterilized is not particularly limited. In the example shown in FIG. 1A, the needleless connector 200 has a housing 210 and a sleeve 220. The sleeve 220 is housed in the housing 210. The top portion 201 of the needleless connector 200 is a portion that receives the male luer from the catheter on the drug solution side, and the bottom portion 202 of the needleless connector 200 is a portion that is connected to the catheter on the human body side.

As a method of connecting the male luer of the catheter to the needleless connector 200, there are a split septum type and a mechanical lip type. In the split septum type, the male luer of the catheter on the drug solution side enters the sleeve 220, so that the liquid can pass through the sleeve 220. In the mechanical lip type, when the male luer of the catheter on the drug solution side is pushed in, the sleeve 220 is pushed into the housing 210 and the liquid can pass therethrough.

The material of the housing 210 is not particularly limited as long as it has necessary strength, but from the viewpoint of sterilizing the inside of the needleless connector 200, a material that transmits the ultraviolet light 111 is preferable, and the material of 200 nm to 300 nm is used. A material that transmits deep ultraviolet light in the range is more preferable. Examples of such housing 210 materials include cyclic olefin copolymers, polymethylpentene, cyclic block copolymers, and the like. Specific examples of the material of the housing 210 include TPX-RT18 manufactured by Mitsui Chemicals, Inc., ViviOn manufactured by USI, and the like.

On the other hand, the material of the sleeve 220 is not particularly limited as long as it has the necessary strength, but from the viewpoint of sterilizing the inside of the needleless connector 200, a material that transmits the ultraviolet light 111 is preferable, and it is 200 nm or more. A material that transmits deep ultraviolet light in the range of 300 nm is more preferable. Examples of the material of the sleeve 220 include colorless or colored silicone resin. Examples of specific silicone resins include LSR-7060 and LSR-7080HP from Momentive, Dow Silicone MS-1002 from Toray Industries, Inc., and similar silicone resins from Shin-Etsu Chemical Co., Ltd., and the like.

(Operation of sterilizer)
Next, a method of sterilizing the needleless connector 200 by the sterilization device 100 will be described.

As shown in FIG. 1B, when sterilizing the needleless connector 200, for example, at least a part of the needleless connector 200 is accommodated.

When the ultraviolet light 111 is emitted from the light source 110, a part of the emitted ultraviolet light 111 directly reaches the needleless connector 200, and the other part of the emitted ultraviolet light 111 is reflected by the reflection part 120. It becomes the reflected light 112 and reaches not only the portion of the needleless connector 200 on the light source 110 side (top portion 201) but also the portion on the opposite side (bottom portion 202). Further, when the needleless connector 200 (particularly the housing 210) is made of a material that transmits the ultraviolet light 111, the ultraviolet light 111 (reflected light 112) also reaches the inside of the needleless connector 200. As a result, substantially the entire surface of the needleless connector 200 is sterilized by the ultraviolet light 111.

(effect)
As described above, in the sterilization apparatus 100 according to the embodiment of the present invention, not only the ultraviolet light 111 directly reaching from the light source 110 but also the ultraviolet light 111 (reflected light 112) reflected by the reflector 120 is used. Since 200 is sterilized, substantially all surfaces of needleless connector 200 are sterilized by UV light 111.

(Simulation 1)
In order to know the sterilization effect of the sterilizer according to the embodiment of the present invention, an illuminance of ultraviolet light with respect to the needleless connector was simulated using an optical model. The configuration of the needleless connector used for the simulation and the simulation conditions will be described below.

FIG. 3A and FIG. 3B are views showing a sleeve of a needleless connector to be sterilized which is used in the simulation. FIG. 3A is a diagram showing a part of the cross section of the sleeve on the ZY plane, and FIG. 3B is a diagram showing the appearance of the sleeve. The sleeve shape shown in FIG. 3B is obtained by rotating the cross section shown in FIG. 3A with the Z axis as the rotation axis. As shown in FIG. 3A, the sleeve has a length of 20 mm and a maximum outer diameter of 8 mm.

The material of the sleeve was a silicone resin (LSR-7080HP) from Momentive. With respect to light having a wavelength of λ265 nm, the refractive index n of this resin was 1.47734 and the absorption coefficient k of this resin was 0.00001.

FIG. 3C is a graph showing an ultraviolet light transmission spectrum of a silicone resin (LSR-7080HP) having a thickness of 1 mm. It can be seen from FIG. 3C that the transmittance of deep ultraviolet light having a wavelength of 265 nm is about 60%.

FIG. 4A and FIG. 4B are views showing the housing of the needleless connector to be sterilized used in the simulation. FIG. 4A is a diagram showing a part of the cross section of the housing on the ZY plane, and FIG. 4B is a diagram showing the appearance of the housing. The shape of the housing shown in FIG. 4B is obtained by rotating the cross section shown in FIG. 4A with the Z axis as the rotation axis.

The material of the housing was polymethylpentene (TPX-RT18) manufactured by Mitsui Chemicals, Inc. With respect to light having a wavelength of λ265 nm, the refractive index n of this resin was 1.4763, and the absorption coefficient k of this resin was 0.00002.

FIG. 4C is a graph showing an ultraviolet light transmittance spectrum of a plate of TPX-RT18 having a thickness of 1 mm. It can be seen from FIG. 4C that the transmittance of deep ultraviolet light having a wavelength of 265 nm is about 23%.

FIG. 5A is a diagram showing an optical model according to a comparative example using the needleless connector 500 including the sleeve shown in FIG. 3B and the housing shown in FIG. 4B. In this optical model, the reflector 120 is not used. In the optical model of FIG. 5A, a light emitting diode 510 that emits deep ultraviolet light is arranged at a position 5 mm away from the top 201 of the needleless connector 500. The light emitting diode 510 is a Lambertian light source having a central wavelength of 265 nm and a light emitting region of 1×1 mm. The output of one light emitting diode 510 was 30 mW. Note that examples of such a light emitting diode include a light emitting diode manufactured by Nikkiso Co., Ltd., a light emitting diode manufactured by Asahi Kasei Co., Ltd., a light emitting diode manufactured by Stanley Electric Co., Ltd., and a light emitting diode manufactured by DOWA Electronics Co., Ltd.

FIG. 5B is a diagram showing an optical model 1 using the sterilizer according to the embodiment, which uses the needleless connector 500 including the sleeve shown in FIG. 3B and the housing shown in FIG. 4B. In this optical model 1, the needleless connector 500 is arranged inside the reflection section 520. The parameters of the reflector 520 (compound parabolic concentrator) are as follows: inner diameter 2a _in =17.543 mm of larger opening, inner diameter 2a _out =6 mm of smaller opening, incident angle range θ _{i of} light. =20°, and the total length L=32.34 mm. Here, a light emitting diode 510 for irradiating deep ultraviolet rays is installed at the position of the top 521 (outlet) of the compound parabolic concentrator, and the needle 10 mm below the top 521 of the compound parabolic concentrator. The top 201 of the Nesconnector 500 was installed.

In this simulation, assuming that the illuminometer was placed on the central axis of the needleless connector, the illuminance distribution in the direction orthogonal to this central axis was measured. Specifically, ray tracing was performed by the Monte Carlo method, and the illuminance at each point was calculated. Light tools by Synospsys in the US and Opticstudio by Zemax in the US are well known as optical calculation software capable of performing such calculation.

Under the above conditions, the illuminance distribution at the positions of 5 mm, 10 mm, and 20 mm from the top 201 to the bottom 202 of the needleless connector was calculated.

6A, 6B, 6C are graphs showing illuminance distributions at positions of 5 mm, 10 mm, and 20 mm from the top 201 of the needleless connector 500 in the optical model according to the comparative example shown in FIG. 5A. 6D, E, and F are graphs showing illuminance distributions at positions of 5 mm, 10 mm, and 20 mm from the top 201 of the needleless connector 500 in the optical model 1 according to the example shown in FIG. 5B. The scale of the vertical axis is different in each graph.

Comparing FIG. 6A and FIG. 6D, FIG. 6B and FIG. 6E, and FIG. 6C and FIG. 6F, respectively, the difference in illuminance distribution between the optical model according to the comparative example of FIG. 5A and the optical model 1 according to the embodiment of FIG. .. That is, in the embodiment, the illuminance at the position away from the top 201 of the needleless connector 500 does not drop much, which is considered to be due to the effect of the light being confined in the needleless connector 500 by the reflection part 520. ..

(Simulation 2)
In order to know the sterilizing effect of the sterilizing apparatus according to the embodiment of the present invention, the illuminance of ultraviolet light with respect to the needleless connector was simulated using the optical model 2. The optical model 2 will be described below, but the same components as those of the optical model 1 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 7 is a diagram showing the optical model 2 according to the embodiment of the present invention. The optical model 2 of FIG. 7 is different from the above optical model 1 in that the light emitting diode 510 is installed in the reflection part 520 at a position 5 mm from the top 521 of the reflection part 520.

8A, 8B and 8C are graphs showing illuminance distributions at 5 mm, 10 mm and 20 mm from the top 201 of the needleless connector 500 in the optical model 2 shown in FIG. The scale of the vertical axis is different in each graph.

Comparing FIGS. 8A, B, and C with FIGS. 6D, E, and F, the optical model 2 in which the light emitting diode 510 is installed at a position 5 mm below the apex 521 is closer to the optical model 1 than the apex 201 of the needleless connector 500. It turned out that the illuminance did not drop to a distant position.

(Simulation 3)
In order to know the sterilization effect of the sterilizer according to the embodiment of the present invention, the illuminance of ultraviolet light with respect to the needleless connector was simulated using the optical model 3. The optical model 3 will be described below, but the same components as those of the optical model 1 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 9 is a diagram showing the optical model 3 according to the embodiment of the present invention. The optical model 3 of FIG. 9 is different from the optical model 1 in that the reflecting section 920 is used as the reflecting section.

The parameters of the reflector 920 (parabolic concentrator) are as follows: inner diameter 2a _in =18.43 mm of the larger opening, inner diameter 2a _out =6 mm of the smaller opening, incident angle range of light θ _i = The angle was 19° and the total length L was 35.47 mm. As described above, the reflection section 920 used in the optical model 3 is slightly larger than the reflection section 520 used in the optical model 1. The light emitting diode 510 was installed on the top portion 921 of the reflecting portion 920.

10A, 10B, and 10C are graphs showing illuminance distributions at respective positions of 5 mm, 10 mm, and 20 mm from the top 201 of the needleless connector 500 in the optical model 3 shown in FIG. In, the scale of the vertical axis is different.

Comparing FIGS. 10A, B, and C with FIGS. 6D, E, and F, the illuminance distribution of the optical model 3 is similar to that of the optical model 1 in that the illuminance at the position away from the top 201 of the needleless connector 500 is too low. However, it is considered that the light is confined in the needleless connector 500 by the reflecting portion 920.

(Simulation 4)
In order to know the sterilizing effect of the sterilizing apparatus according to the embodiment of the present invention, the optical model 4 was used to perform a simulation of the illuminance of ultraviolet light on the needleless connector. The optical model 4 will be described below, but the same components as those of the optical models 1 and 3 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 11 is a diagram showing the optical model 4 according to the embodiment of the present invention. The optical model 4 of FIG. 11 is different from the above optical model 3 in that the light emitting diode 510 is installed in the reflection section 920 at a position 2.5 mm from the top 921 of the reflection section 920.

12A, B, and C are graphs showing illuminance distributions at respective positions of 5 mm, 10 mm, and 20 mm from the top 201 of the needleless connector in the optical model 4 shown in FIG. The vertical scale is different.

Comparing FIGS. 12A, B, and C with FIGS. 10A, B, and C, the optical model 4 in which the light emitting diode 510 is installed at a position 2.5 mm from the top 921 is closer to the optical model 2 than the top 201 of the needleless connector 200. It was found that the illuminance did not drop to a position further away.

(Simulation 5)
In order to know the sterilizing effect of the sterilizing apparatus according to the embodiment of the present invention, the illuminance of ultraviolet light with respect to the needleless connector was simulated using the optical model 5. The optical model 5 will be described below, but the same components as those of the optical models 1 and 3 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 13 is a diagram showing the optical model 5 according to the embodiment of the present invention. The optical model 5 of FIG. 13 differs from the optical model 3 described above in that the light emitting diode 510 is installed in the reflection section 920 at a position 5 mm from the top 921 of the reflection section 920.

14A, 14B and 14C are graphs showing illuminance distributions at 5 mm, 10 mm and 20 mm from the top 201 of the needleless connector 500 in the optical model 5 shown in FIG. 13, respectively. In, the scale of the vertical axis is different.

Comparing FIGS. 14A, B, and C with FIGS. 10A, B, and C, and FIGS. 12A, B, and C, the optical model 5 in which the light emitting diode 510 is installed at a position 5 mm from the top 921 is more than the optical models 3 and 4. It was found that the illuminance did not drop to a position further away from the top 201 of the needleless connector 200.

(Summary of simulation)
From the above simulations 1 to 5, by changing the position of the light emitting diode 510 (light source 110), the illuminance at a specific position from the top 201 of the needleless connector 500 is increased and the specific portion of the needleless connector 500 is sterilized. It can be seen that the action can be strengthened.

According to the sterilizer of the present invention, a wider range of the needleless connector can be sterilized. Therefore, according to the present invention, the occurrence of catheter-related bloodstream infections can be reduced.

100 Sterilizer 110 Light source 111 Ultraviolet light 112 Reflected light 120, 520, 920 Reflector 121, 201, 521, 921 Top 123 Reflective surface 200, 500 Needleless connector 202 Bottom 210 Housing 220 Sleeve 510 Light emitting diode

Claims (5)

A sterilizing device for sterilizing a needleless connector,
A light source that emits ultraviolet light,
A reflecting portion having a reflecting surface configured so that the inner diameter increases as the distance from the light source increases, and a reflecting portion for reflecting the ultraviolet light emitted from the light source toward the needleless connector,
Sterilizer having a. The sterilizer according to claim 1, wherein the reflective surface includes a parabolic surface. The sterilizer according to claim 1 or 2, wherein the reflector is a compound parabolic concentrator. The sterilizer according to claim 1, wherein the reflective surface is a surface of an aluminum layer. The sterilizer according to any one of claims 1 to 4, wherein the light source is arranged inside the reflecting portion.

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