Liquid chemical sterilization system using biological indicators.

Abstract

To provide a device and a technique for evaluating the validity of a liquid chemical sterilization routine applied particularly to an endoscope sterilization.SOLUTION: A method for determining the sterility of a medical device sterilized by a sterilization system includes the steps of: inserting a vial housing a carrier of microorganisms into a cavity; penetrating a needle into the vial; introducing liquid-chemical sterilant into the vial through the needle; incubating the vial in which the liquid-chemical sterilant is arranged; drawing the liquid-chemical sterilant from the vial through the needle; introducing neutralizer into the vial through the needle; drawing the neutralizer from the vial through the needle; introducing a growth medium into the vial through the needle; and incubating the vial in which the growth medium is arranged.SELECTED DRAWING: Figure 1

Description

Disclosure Contents

[0001] [Field] The subject matter disclosed herein relates to instruments and techniques for assessing the adequacy of liquid chemical sterilization routines, particularly as applied to endoscope sterilization.

[0002] 〔background〕 Medical devices are typically sterilized before use to minimize the possibility of a contaminated device being used on a subject, which could cause an infection in the subject. A variety of sterilization techniques can be used, such as steam, hydrogen peroxide, and vapor-phase sterilization, with or without gas plasma and ethylene oxide (EtO).

[0003] Certain sterilization techniques are performed at ambient or non-atmospheric pressures. For example, the STERRAD® System, STERRAD® NX System, or STERRAD® 100NX System from Advanced Sterilization Products, a division of Ethicon US, LLC, a Johnson & Johnson company, are examples of sterilization systems or sterilizers that vaporize hydrogen peroxide and operate at low pressures, e.g., less than 200 millitorr.

[0004] Various elongated medical devices with lumens, such as endoscopes, are difficult to sterilize with vapor sterilants, such as vaporized hydrogen peroxide, for a variety of reasons. For example, because pressure within the lumen decreases as a function of length and diameter from the lumen entrance, a pressure drop must be overcome to ensure the sterilant passes through the entire lumen and reaches all surfaces of the lumen. Additionally, the lumen may collect debris or be blocked by fluids such as rinse water.

[0005] Steam-based sterilization routines often incorporate sterilization indicators, such as biological or chemical indicators, which can provide an indication of the effectiveness of the sterilization cycle. While such indicators may be positioned near the endoscope within the sterilization chamber, they may not be reliable for assessing the sterility of the endoscope because the parts of the endoscope that are most difficult to sterilize are typically deep within the endoscope lumen.

[0006] [Disclosure Summary] Disclosed herein is a sterilization system including a vial, a carrier disposed within the vial, and a fluid management system. The fluid management system includes an output connectable to the vial to deliver a liquid to the vial. Such liquid includes at least a liquid chemical sterilant (e.g., peracetic acid) and a neutralizing agent (e.g., sodium metabisulfite). Thus, the fluid management system can include a source of liquid chemical sterilant and a source of neutralizing agent. The sterilization system can further include an instrument including a first segment having a needle connected to the output of the fluid management system and a second segment having a cavity that accommodates the vial. The first and second segments can be connected by a hinge, and when the first segment rotates about the hinge, the needle penetrates the vial. The vial can include a cover that can also be penetrated by the needle. A medical device (e.g., an endoscope) having a lumen can be connected between the needle and the output.

[0007] The carrier in the vial may contain, for example, spores or microorganisms disposed thereon or therein. For example, the carrier may contain Geobacillus stearothermophilus spores. The sterilization system may include a growth medium (e.g., α-MUG) that can be used to promote the growth of the spores or microorganisms. Thus, the fluid management system may include a source of liquid growth medium. Alternatively or additionally, growth medium may be provided in a second vial and disposed within the second cavity.

[0008] A sterilization system can be used to determine the sterility (or lack thereof) of a medical device that has undergone or is undergoing a sterilization cycle in the sterilization system. This method can include inserting a vial containing a microbial carrier into a cavity of an instrument, penetrating a needle into the vial, and introducing a liquid chemical sterilant through the needle and into the vial. Additionally, a lumen of a medical device, such as an endoscope, can be connected between a source of sterilant and the needle, with the sterilant flowing through the lumen before being introduced into the vial. The vial can then be incubated at about 30°C to about 50°C, e.g., 35°C, while the liquid chemical sterilant is disposed therein. After incubation, the liquid chemical sterilant can be withdrawn from the vial through the needle.

[0009] A neutralizing agent may then be introduced into the vial through the needle and then withdrawn from the vial through the needle. Growth medium may then be introduced into the vial through the needle from a growth medium source in the fluid management system or from a second vial disposed in the second cavity of the device. The vial, i.e., the vial with the carrier and growth medium disposed therein, may then be incubated at about 50°C to about 60°C, e.g., 57°C.

[0010] While the vial is being incubated, the visual characteristics of the growth medium can be monitored to determine changes to the visual characteristics, which can include fluorescence intensity.

[0011] At any step in the sterilization cycle, preferably the first or final step, the system can be sterilized by flowing a liquid chemical sterilant through at least some of its fluid components, such as tubing, valves and pumps.

[0012] The specification concludes with claims particularly pointing out and distinctly claiming the subject matter described herein, which subject matter will be better understood from the following description of specific embodiments taken in conjunction with the accompanying drawings, in which like reference numerals identify the same elements and in which: [Brief explanation of the drawings]

[0013] [Figure 1] 1 depicts a schematic diagram of an instrument in an open configuration used with a liquid chemical sterilization system to aid in the evaluation of sterilization efficacy. [Figure 2] 2 depicts a schematic diagram of the device of FIG. 1 in a closed configuration. [Figure 3] FIG. 3 depicts a block diagram of a fluid management system for use with the instrument and liquid chemical sterilization system of FIGS. 1 and 2.

[0014] [Mode for Carrying Out the Invention] The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. The detailed description illustrates the principles of the invention by way of example, but not by way of limitation. This description clearly enables one skilled in the art to make and use the invention and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is currently contemplated to be the best mode for carrying out the invention.

[0015] As used herein, the term "about" or "approximately" in connection with any numerical value or range indicates an appropriate dimensional tolerance that enables a collection of parts or components to function for its intended purpose, as described herein. More specifically, "about" or "approximately" can refer to a range of values ​​of ±10% of the recited value; for example, "about 90%" can refer to a range of values ​​of 81% to 99%. Furthermore, as used herein, the terms "patient," "host," "user," and "subject" refer to any human or animal subject and are not intended to limit the system or method to human use, although use of the present invention in human patients represents a preferred embodiment.

[0016] Automated sterilization equipment and routines for endoscopes using liquid chemical sterilants, such as hydrogen peroxide or peracetic acid, have been developed to overcome certain drawbacks associated with sterilization of endoscopes using steam-chemical sterilants. However, as with steam-based processes, developing reliable techniques for assessing whether an endoscope has been sterilized remains a challenge. Furthermore, biological indicators used in steam-based processes are not suitable for use with liquid-based processes because such indicators are designed to remove gaseous sterilants, but not liquid sterilants. Furthermore, such indicators typically require the user to destroy the ampoule containing the growth medium. Therefore, when liquid chemical sterilants are used, the risk of burns to the user from residual liquid sterilant remains. Therefore, it would be advantageous to provide a system capable of operating a biological indicator for use with liquid chemical sterilants that does not require user intervention. However, such systems should be designed to be sterilized to avoid the accumulation of contaminants. Proposed herein are devices and methods that can be used to determine whether an endoscope has been sterilized by a sterilization routine using a liquid chemical sterilant that further address these design requirements.

[0017] 1 and 2 depict an instrument 100 that may be used with or form part of a liquid chemical sterilization system. The instrument 100 can assist in the evaluation of medical devices, particularly endoscopes, undergoing sterilization routines by the system. FIG. 1 depicts the instrument 100 in an open, unused configuration, while FIG. 2 shows the instrument 100 in a closed configuration. The instrument 100 includes a first segment 102 joined to a second segment 104 by a hinge 106, e.g., a live hinge. A first cavity 108 and a second cavity 110 may be formed within the second segment 104. Tubular passages suitable for holding capillary tubes or hollow needles, e.g., first needle 116 and second needle 118, may be formed within the first segment 102. Additionally, heating elements, such as heating coils 136 and 138, may be disposed within the second segment 104. Heating coils 136 and 138 are preferably positioned adjacent to cavity 108 so that they can be used to heat a liquid placed in cavity 108. Heating coils 136 and 138 can include contacts at their bottoms for conducting electricity. Although not shown, instrument 100 can further include components such as a light source and a photodetector that can evaluate changes to the visual characteristics of the liquid, for example, a color change or a change in fluorescence intensity of the liquid in first cavity 108. Alternatively, such components can be located adjacent to where cavity 108 may be placed in a sterilization system.

[0018] The first cavity 108 and the second cavity 110 are suitable for holding a liquid. Alternatively or additionally, they are suitable for maintaining the position of a vial placed therein. For example, as shown in FIG. 1 , a first vial 112 can be placed in the first cavity 108, and a second vial 114 can be placed in the second cavity 110. In embodiments in which a liquid is placed directly in one or both of the cavities, i.e., without a vial, the cavity can be sealed with a cover that can be broken to access the fluid. For example, a layer of foil, e.g., aluminum, can be used to cover the cavity 108, the cavity 110, or both. The foil layer can be broken or pierced, e.g., by needles 116, 118, or both. In embodiments incorporating the first vial 112, the second vial 114, or both, the vials can be individually covered to seal the vials. 1 and 2, the first vial 112 includes a cover 120 and the second vial 114 includes a cover 122. Thus, the vials 112 and 114 may be provided as sterile consumables that may be placed into the cavities 108 and 110 before starting a sterilization routine and removed therefrom after the sterilization routine.

[0019] Vials 112 and 114 may further include a biological indicator feature. Specifically, a disk or carrier 132 containing or impregnated with a source of microorganisms, such as spores or active enzymes. Carrier 132 may be placed within first vial 112. Spores from Bacillus, Geobacillus, and Clostridium species are often used to monitor sterilization processes using chemical sterilants. Thus, carrier 132 may be impregnated with spores from Bacillus, Geobacillus, and / or Clostridium species. For example, the sterilization process resistant spores may include, but are not limited to, at least one of Geobacillus stearothermophilus spores, Bacillus subtilis spores, Bacillus atrophaeus spores, Bacillus megaterium spores, Bacillus coagulans spores, Clostridium sporogenes spores, Bacillus pumilus spores, and combinations thereof.

[0020] The carrier 132 may be water-absorbent and may be formed from filter paper. Sheet-like materials such as cloth, nonwoven polypropylene, rayon, or nylon, and microporous polymeric materials may also be used. Non-water-absorbent materials such as metal (e.g., aluminum or stainless steel), glass (e.g., glass beads or fiberglass), porcelain, or plastic are also suitable for use. Additionally, the carrier 110 may be constructed from a combination of the above-mentioned materials. In some embodiments, the carrier 110 may have a thickness of approximately 0.1 to 0.5 mm.

[0021] Additionally, a growth medium 134 can be placed in the second vial 114. The growth medium must be capable of promoting the growth of any viable microorganisms or other biologically active sources placed on the carrier 132. Preferably, the microorganisms are selected to produce an enzyme that interacts with the growth medium's enzyme substrate to create a change in the visual characteristics of the growth medium, for example, by causing a color change or a change in fluorescence intensity in the growth medium. As the microorganisms continue to grow in the growth medium, the concentration of the detectable product in the growth medium increases. In certain embodiments, the detectable product is a fluorophore. Thus, an increase in the concentration of the detectable product causes an increase in fluorescence. That is, the detectable product is detectable via a change in fluorescence intensity.

[0022] Enzymes and enzyme substrates that can be used to detect the efficacy of a sterilization cycle are identified in U.S. Pat. No. 5,073,488, entitled "Rapid Method for Determining Efficacy of a Sterilization Cycle and Rapid Read-Out Biological Indicator," issued December 17, 1991, the disclosure of which is incorporated herein by reference; U.S. Pat. No. 5,418,167, entitled "Rapid Read-Out Biological Indicator," issued May 23, 1995, the disclosure of which is incorporated herein by reference; U.S. Pat. No. 5,223,401, entitled "Rapid Read-Out Sterility Indicator," issued June 29, 1993, the disclosure of which is incorporated herein by reference; and U.S. Pat. No. 9,322,046, entitled "Biological Sterilization Indicator," issued April 26, 2016, the disclosure of which is incorporated herein by reference.

[0023] Suitable enzymes may include hydrolases and / or enzymes derived from spore-forming microorganisms such as Bacillus subtilis. Exemplary enzymes derived from spore-forming microorganisms that may be useful in biological indicators include β-D-glucosidase, α-D-glucosidase, alkaline phosphatase, acid phosphatase, butyrate esterase, caprylate esterase, lipase, myristate lipase, leucine aminopeptidase, valine aminopeptidase, chymotrypsin, phosphohydrolase, α-D-galactosidase, β-D-galactosidase, tyrosine aminopeptidase, phenylalanine aminopeptidase, β-D-glucuronidase, α-L-arabinofuranosidase, N-acetyl-β-glucosaminoidase, β-D-cellobiosidase, alanine aminopeptidase, proline aminopeptidase, fatty acid esterase, and combinations thereof.

[0024] In some exemplary methods for determining the efficacy of a sterilization cycle as disclosed herein, an enzyme substrate is converted to a detectable product. For example, the enzyme substrate may be characterized by a first emission spectrum (e.g., a first fluorescent emission spectrum), and the detectable product may be characterized by a second emission spectrum (e.g., a second fluorescent emission spectrum).

[0025] In some exemplary methods for determining the efficacy of a sterilization cycle as disclosed herein, suitable enzyme substrates for use may include fluorogenic enzyme substrates. Useful fluorogenic enzyme substrates may be selected from fluorogenic 4-methylumbelliferyl derivatives (hydrolyzable to 4-methylumbelliferone ("4-Mu")), derivatives of 7-amido-4-methyl-coumarin, diacetylfluorescein derivatives, fluorescamine, and combinations thereof.

[0026] Exemplary 4-methylumbelliferyl derivatives include 4-methylumbelliferyl-2-acetamido-4,6-O-benzylidene-2-deoxy-β-D-glucopyranoside, 4-methylumbelliferyl acetate, 4-methylumbelliferyl-N-acetyl-β-D-galactosaminide, 4-methylumbelliferyl-N-acetyl-α-D-glucosaminide, 4-methylumbelliferyl-N-acetyl-β-D-glucosaminide, 2'-(4-methylumbelliferyl)-α-DN-acetylneuraminic acid, 4-methylumbelliferyl Umbelliferyl α-L-arabinofuranoside, 4-methylumbelliferyl α-L-arabinoside, 4-methylumbelliferyl butyrate, 4-methylumbelliferyl 13-D-cellobioside, methylumbelliferyl β-DN, N'-diacetylchitobioside, 4-methylumbelliferyl elaidate, 4-methylumbelliferyl β-D-fucoside, 4-methylumbelliferyl α-L-fucoside, 4-methylumbelliferyl β-L-fucoside, 4-methylumbelliferyl α-D-galactoside, 4-methylumbelliferyl 4-Methylumbelliferyl β-D-galactoside, 4-methylumbelliferyl α-D-glucoside, 4-methylumbelliferyl β-D-glucoside, 4-methylumbelliferyl (3-D-glucuronide), 4-methylumbelliferyl p-guanidinobenzoate, 4-methylumbelliferyl heptanoate, 4-methylumbelliferyl α-D-mannopyranoside, 4-methylumbelliferyl β-D-mannopyranoside, 4-methylumbelliferyl oleate, 4-methylumbelliferyl palmitate, 4-methylumbelliferyl The 4-methylumbelliferyl phosphate, 4-methylumbelliferyl propionate, 4-methylumbelliferyl stearate, 4-methylumbelliferyl sulfate, 4-methylumbelliferyl β-DN,N′,N″-triacetylchitotriose, 4-methylumbelliferyl 2,3,5-tri-o-benzoyl-α-L-arabinofuranoside, 4-methylumbelliferyl-p-trimethylammonium cinnamate chloride, 4-methylumbelliferyl β-D-xyloside, and combinations thereof.

[0027] In certain embodiments, the fluorescent response can be based on the naturally occurring α-glucosidase enzyme found in Geobacillus stearothermophilus spore coats, which contains an enzyme believed to be important in the germination of Geobacillus stearothermophilus. α-Glucosidase can be used to hydrolyze the bond between the 4-methylumbelliferyl moiety and glucose in 4-methylumbelliferyl α-D-glucopyranoside (α-MUG). α-MUG is not fluorescent. However, after hydrolysis and separation of the moieties, the 4-methylumbelliferone (4-MU) product is fluorescent. 4-MU fluoresces when excited by an external energy source, such as a light source that emits light having a wavelength of approximately 360 nm to 370 nm. When excited in this manner, 4-MU emits light having a wavelength of approximately 440 nm to 460 nm. In a specific embodiment, the light source emits light having a wavelength of about 365 nm, and 4-MU emits light having a wavelength of 450 nm. The fluorescence of 4-MU is pH dependent. For example, when excited by light having a wavelength of 365 nm, the intensity of the emitted light is highest at pH 10.3. This intensity decreases with pH up to approximately pH 7. Below this pH, the intensity becomes negligible.

[0028] Based on the foregoing, since the carrier 132 and growth medium 134 are combined within the vial 112, the vial 112 may be considered a biological indicator.

[0029] Needles 116 and 118 are aligned with cavities 108 and 110, respectively, so that when device 100 is transitioned from the open configuration of FIG. 1 to the closed configuration of FIG. 2, needles 116 and 118 can pierce covers 120 and 122 and enter vials 112 and 114, respectively, to introduce or remove liquid from vials 112 and 114. Needles 116 and 118 should be long enough to contact or nearly contact the bottom of the corresponding vial in the closed configuration to remove all or substantially all of the liquid therefrom. When carrier 132 is positioned at the bottom of vial 112, needle 116 can contact or nearly contact that surface.

[0030] Instrument 100, i.e., at least first segment 102, second segment 104, and hinge 106, can be manufactured by any suitable manufacturing method, such as injection molding, machining, or 3D printing. In embodiments in which some features, such as needles 116 and 118 and heating coils 136 and 138, are manufactured by separate processes, they may be assembled and secured within the instrument, for example, by press fitting or using an adhesive such as epoxy.

[0031] Tubing may be connected to needles 116 and 118 to allow for the transfer of fluids from the cavities or vials. For example, a first tube 124 may be connected to needle 116, and a second tube 126 may be connected to needle 118. Tubing 124 and 126 may each be connected to a third tube 128 through a multi-way valve 130. Tubing 128 may be connected to a fluid management system 200 of a liquid sterilization system, which may introduce and remove various liquids to and from vials 112 and 114.

[0032] A fluid management system 200 for a liquid sterilization system is shown in block form in FIG. 3. System 200 includes various sources of liquid, such as a source 250 of a liquid chemical sterilant, such as peracetic acid or hydrogen peroxide, and a source 252 of a liquid reducing or neutralizing agent, such as sodium metabisulfite or sodium bisulfite, that can be used to neutralize the sterilant. Optionally, a source 254 of growth medium may also be provided. In embodiments including a source 254 of growth medium, system 200 may be used with instruments 100 that lack cavity 110, vial 114, and growth medium 134. System 200 may also include a drain 256.

[0033] Various tubes and valves connect sources 250 and 252 (and 254, if used) and drain 256 to instrument 100 via tubes 124 and 128 (and 126, if source 254 is not used). In some embodiments, endoscope 10 can be positioned between system 200 and tube 128 so that fluid from any one of sources 250, 252, or 254 first flows through the endoscope's lumen before entering vial 112. Typically, however, only sterilant from source 250 flows through endoscope 10, which can aid in the assessment of sterility achieved with vial 112 and should provide a more accurate indication of the endoscope's lumen.

[0034] 3, system 200 includes tubes 260, 262, 264, 266, 268, 269, 270, 272, 274, 278, 280, 281, and 283. Any of tube 280, valve 289, or the junction between valve 289 and tube 128 may be considered an output from system 200 and, therefore, may be referred to herein as an output. System 200 also includes valves 282, 284, 286, 288, and 289, which may be three-way valves. System 200 also includes pumps 290 and 292. Thus, sterilant from source 250 may be advanced by pump 292 from source 250 to vial 112 through tubing 260, valve 282, tubing 269, valve 284, tubing 270, valve 286, tubing 272, valve 288, tubing 278, tubing 280, and then output from system 200 through valve 289 to tubing 128, tubing 124, and needle 116. Optionally, before a portion of the sterilant is output from system 200 through valve 289, the sterilant may flow through a recirculation line that includes tubing 281, the lumen of the medical device (e.g., endoscope 10), tubing 283, tubing 278, tubing 280, and valve 289. Neutralizing agent from source 252 can be advanced by pump 292 from source 252 to vial 112 through tube 262, valve 282, tube 269, valve 284, tube 270, valve 286, tube 272, valve 288, tube 278, tube 280, and then output from system 200 through valve 289 to tube 128, tube 124, and needle 116.

[0035] Growth medium can be supplied to vial 112 from vial 114 or from source 254. Referring to FIG. 2 , when growth medium 134 is supplied from vial 114 to vial 112, valve 130 is oriented so that tubes 128 and 126 are in fluid communication but not in fluid communication with tube 124. Growth medium 134 can be removed from vial 114 under pressure generated by pump 290 until growth medium 134 is contained within tube 128. Valve 130 is then reoriented so that tubes 128 and 124 are in fluid communication but not in fluid communication with tube 126. Growth medium 134 can then be advanced from tube 128 into vial 112 under pressure generated by pump 292. When growth medium is supplied from source 254, it can be advanced by pump 292 from source 254 to vial 112 through tube 264, valve 284, tube 270, valve 286, tube 272, valve 288, tube 278, tube 280, and then output from system 200 through valve 289 to tube 128, tube 124, and needle 116.

[0036] Draining or flushing the system can be accomplished by opening valves and operating pump 290 so that liquid can flow through tubes 266 and 268 into drain 256. Draining can be useful for priming system 200, sterilizing system 200, or preparing system 200 for reuse.

[0037] The sterilization system may further include a processor, a non-transitory storage medium, and a user interface. The non-transitory storage medium may include computer-executable instructions or software that can instruct the processor to activate various pumps and direct various valves so that fluid may be transferred from sources 250, 252, 254 (if included) to vials 112, 114 (if included) as described above. The processor may also receive input from a photodetector so that it can determine if there has been any change to the color or fluorescence of the growth medium and, based thereon, either abort the sterilization cycle or provide feedback to the user via the user interface.

[0038] In accordance with the embodiments shown and described herein, the applicant has devised a method and variations thereof for evaluating the efficacy of a sterilization routine performed by an automated liquid chemical sterilization system. The method and variations may include the following steps: First, a vial (e.g., 112) containing a microbial carrier (e.g., 132) may be provided. The vial may be placed in a cavity to accommodate it, and positioned relative to a tube or needle (e.g., 116, 280) that may be inserted therein, which may include penetrating a barrier (e.g., 120) sealing the top of the vial. Further, penetrating the barrier may include closing an instrument (e.g., 100) to change the instrument's configuration from an open configuration (e.g., FIG. 1) to a closed configuration (e.g., FIG. 2), thereby penetrating the barrier and placing the needle into the vial. The instrument 100 may be placed in a sterilization chamber of a sterilization system, whereby the instrument and the exterior of the vial 112 may be subjected to a sterilization routine alongside a medical device, such as an endoscope.

[0039] After the tube or needle is positioned within the vial, various steps of liquid transfer can begin. First, a sufficient amount of liquid chemical sterilant, such as peracetic acid or hydrogen peroxide, to fill the vial is introduced into the vial from a liquid chemical sterilant source, such as source 250. In certain variations, the liquid chemical sterilant can flow through at least one lumen of the endoscope before reaching vial 112. The vial and sterilant can then be heated, for example, via heating elements 136 and 138, to about 30°C to about 60°C, which helps the sterilant kill microorganisms within the BI by increasing the inactivation rate between the sterilant and the microorganisms. With peracetic acid, the inactivation rate can be maximized at about 35°C. The liquid chemical sterilant can then be removed from the vial and vented from the system. Second, a sufficient amount of neutralizing agent, such as sodium metabisulfite or sodium bisulfite, to fill the vial is introduced into the vial from a neutralizing agent source, such as source 252. The amount of neutralizing agent can then be removed from the vial and expelled from the system. In a preferred variation, the peracetic acid and neutralizing agent remain in the vial for approximately the same time as they are in contact with the endoscope. Third, growth medium can be introduced into the vial. Two techniques for this are described in detail above.

[0040] With the growth medium in the vial, evaluation of the efficacy of the sterilization cycle may begin. First, the heating elements (e.g., 136 and 138) may be activated to incubate the vial and stimulate the growth of any spores that were able to survive removal of the sterilant. For example, incubation may maintain the vial's temperature at about 50°C to about 60°C, e.g., 57°C, for about 30 minutes. In embodiments in which the instrument 100 includes a light source and detector, the sterilization system may evaluate changes to the visual characteristics of the growth medium in the vial over all or part of the 30 minutes to determine whether any spores were able to survive, and based thereon, determine whether the sterilization cycle was effective. In embodiments in which the instrument 100 does not include a heating element, light source, and detector, or a combination thereof, the vial may be removed from the instrument 100 and sterilization system and placed in the well of a biological indicator evaluation device, such as a reader for the commercially available STERRAD VELOCITY™ system manufactured by the applicant. The STERRAD VELOCITY™ Reader, ASP Part No. 43220, then incubates the vial and evaluates the growth medium therein for the development of any color or fluorescence changes to determine whether the sterilization cycle was effective.

[0041] In a further variation of this method, system 200 can sterilize itself by flowing a liquid chemical sterilant through all of its components. Additionally, system 200 can fill its components with one of the liquids and prime the system with that liquid before beginning the step of introducing a quantity of that liquid into the vial.

[0042] [Embodiment] (1) A sterilization system comprising: A vial, a carrier disposed within the vial; 1. A fluid management system having an output connectable to the vial for delivering a liquid to the vial, the fluid management system comprising: a source of liquid chemical sterilant; and a source of neutralizing agent, a fluid management system including: sterilization system, including: (2) The device further includes: a first segment including a needle connected to the output; a second segment including a cavity for receiving the vial; a hinge connecting the first segment to the second segment such that rotation of the first segment about the hinge causes the needle to penetrate the vial; 2. The sterilization system of claim 1, comprising: (3) The sterilization system of claim 2, further comprising a medical device having a lumen connected between the needle and the output. (4) The sterilization system of claim 3, wherein the medical device comprises an endoscope. (5) The sterilization system of embodiment 2, further comprising a second cavity for receiving a second vial containing a growth medium.

[0043] (6) The sterilization system of claim 2, wherein the fluid management system further comprises a source of growth medium. (7) The sterilization system of claim 6, wherein the instrument further comprises a heating element positioned adjacent to the cavity. 8. The sterilization system of claim 6, wherein the liquid chemical sterilant comprises peracetic acid. (9) The sterilization system of embodiment 8, wherein the growth medium comprises α-MUG. (10) The sterilization system of embodiment 9, wherein the carrier comprises Geobacillus stearothermophilus spores.

[0044] (11) The sterilization system of claim 1, wherein the vial includes a cover. (12) A method for determining the sterility of a medical device sterilized by a sterilization system including an instrument having a cavity and a needle, comprising: Inserting a vial containing a carrier of a microorganism into said cavity; penetrating the needle into the vial; introducing a liquid chemical sterilant through the needle into the vial; incubating the vial with the liquid chemical sterilant disposed therein; withdrawing the liquid chemical sterilant from the vial through the needle; introducing a neutralizing agent into the vial through the needle; withdrawing the neutralizing agent from the vial through the needle; introducing growth medium into the vial through the needle; incubating the vial with the growth medium disposed therein; A method comprising: 13. The method of claim 12, further comprising monitoring a visual characteristic of the growth medium. (14) The method of claim 13, further comprising determining a change in the visual characteristic. (15) The method of embodiment 13, wherein the visual characteristic comprises fluorescence intensity.

[0045] 16. The method of claim 14, further comprising passing a quantity of the liquid chemical sterilant through a lumen of the medical device before introducing the quantity of the sterilant into the vial. (17) The method of embodiment 16, wherein incubating the vial with the growth medium therein comprises heating the vial to a temperature of about 50°C to about 60°C. 18. The method of claim 17, wherein incubating the vial with the growth medium therein comprises heating the vial to about 57°C. 19. The method of claim 17, wherein incubating the vial with the liquid chemical sterilant therein comprises heating the vial to a temperature of about 30° C. to about 50° C. 20. The method of claim 19, wherein incubating the vial with the liquid chemical sterilant therein comprises heating the vial to about 35°C.

[0046] 21. The method of claim 19, wherein the sterilization system includes a plurality of fluid sources, tubing, valves, and pumps, and the method further includes sterilizing at least some of the fluid sources, tubing, valves, and pumps with the liquid chemical sterilant. 22. The method of claim 20, wherein the liquid chemical sterilant comprises peracetic acid. (23) The method of embodiment 16, wherein the medical device comprises an endoscope.

Claims

1. 1. A method for determining the sterility of a medical device sterilized by a sterilization system, comprising: Inserting a vial containing a carrier of a microorganism into the cavity; penetrating a needle into the vial; introducing a liquid chemical sterilant through the needle and into the vial, the liquid sterilant flowing through the lumen of the medical device; incubating the vial with the liquid chemical sterilant disposed therein; withdrawing the liquid chemical sterilant from the vial through the needle; introducing a neutralizing agent into the vial through the needle; withdrawing the neutralizing agent from the vial through the needle; introducing growth medium into the vial through the needle; incubating the vial with the growth medium disposed therein; A method comprising:

2. 10. The method of claim 1, further comprising monitoring and determining a change in the visual characteristics of the growth medium.

3. The method of claim 2 , wherein the visual signature comprises fluorescence intensity.

4. 3. The method of claim 2, further comprising passing a quantity of the liquid chemical sterilant through a lumen of the medical device before introducing the quantity of the liquid chemical sterilant into the vial, wherein the medical device is an endoscope.

5. 5. The method of claim 4, wherein incubating the vial with the growth medium disposed therein comprises heating the vial to a temperature of 50°C to 60°C.

6. 6. The method of claim 5, wherein incubating the vial with the liquid chemical sterilant disposed therein comprises heating the vial to a temperature between 30°C and 50°C.

7. 7. The method of claim 6, wherein the sterilization system includes a plurality of fluid sources, tubing, valves, and pumps, and the method further includes sterilizing at least some of the fluid sources, tubing, valves, and pumps with the liquid chemical sterilant.

8. 7. The method of claim 6, wherein the liquid chemical sterilant comprises peracetic acid or hydrogen peroxide.

9. 10. The method of claim 1, wherein the step of penetrating the needle further comprises moving the sterilization system from an open configuration to a closed configuration so that the needle penetrates a barrier of the vial.

10. The method of claim 1 , wherein the neutralizing agent comprises sodium metabisulfite or sodium bisulfite.

11. 10. The method of claim 1, wherein the liquid chemical sterilant remains in the vial for a first time period and the neutralizing agent remains in the vial for a second time period, the first time period being approximately equal to the second time period.

12. 12. The method of claim 11, wherein the step of incubating the vial with the growth medium disposed therein is for a third period of time approximately equal to 30 minutes.

13. 1. A method for determining sterility of a medical device, comprising: Inserting a vial containing a carrier of a microorganism into a cavity of the device; moving a first segment of the device relative to a second segment of the device to pierce the vial with a needle; introducing at least one fluid into the vial through the needle; incubating the vial with the at least one fluid disposed therein; withdrawing the at least one fluid from the vial through the needle; A method comprising:

14. 14. The method of claim 13, wherein the at least one fluid is a liquid chemical sterilant or a growth medium.

15. 15. The method of claim 14, further comprising the step of introducing a neutralizing agent into the vial through the needle.

16. 14. The method of claim 13, wherein the introducing step is performed by a first pump fluidly connected to the vial by at least one valve and at least one tube, and the withdrawing step is performed by a second pump fluidly connected to the vial by at least one valve and at least one tube.

17. 17. The method of claim 16, wherein a non-transitory storage medium instructs a processor to operate the first pump and the second pump and direct the at least one valve so that the at least one fluid is introduced into or withdrawn from the vial.

18. 14. The method of claim 13, wherein the apparatus further comprises a heating element adjacent to the vial, and wherein the introducing step is performed by the heating element.

19. 14. The method of claim 13, further comprising passing a quantity of the at least one fluid through a lumen of the medical device before introducing the quantity of the at least one fluid into the vial, wherein the medical device is an endoscope.

20. 1. A method for determining sterility of a medical device, comprising: Inserting a vial containing a carrier of a microorganism into a cavity of the device; moving a first segment of the device relative to a second segment of the device to pierce the vial with a needle; introducing a liquid chemical sterilant through the needle and into the vial, the liquid sterilant flowing through the lumen of the medical device; incubating the vial with the liquid chemical sterilant disposed therein; withdrawing the liquid chemical sterilant from the vial through the needle; introducing a neutralizing agent into the vial through the needle; withdrawing the neutralizing agent from the vial through the needle; introducing growth medium into the vial through the needle; incubating the vial with the growth medium disposed therein; A method comprising:

Images