KR100691382B1 - How to monitor the cleaning process - Google Patents

Abstract

The present invention relates to an apparatus and method for monitoring a cleaning process of a medical device. The device includes a contamination detector. The contaminant detector may detect inorganic and / or organic contaminants on medical devices or on standards covered with contaminants that may act as a surrogate indicator of the cleanliness of the medical device or used in cleaning or cleaning monitoring methods. The method of the present invention for monitoring a cleaning process of a medical device includes measuring contaminants removed from the medical device in accordance with the device of the present invention including a contamination detector. Preferably, the method further comprises determining when the device is sufficiently cleaned to be sterilized.

Description

How to monitor the cleaning process

(Related application)

This application claims the benefits of pre-application 60/049351, filed June 11, 1997, entitled "DETECTION OF CLEANLINESS OF A MEDICAL DEVICE DURING A WASHING PROCESS."

(Background of invention)

Field of invention

The present invention relates to an apparatus and method for monitoring a cleaning process of a medical device. More specifically, the present invention relates to an apparatus and method that can determine when a medical device is sufficiently cleaned to be sterilized.

Description of the related technology

Proper cleaning of contaminated medical instruments and devices is essential for safe disinfection and sterilization. Failure to properly remove inorganic and organic soils derived from body fluids and body tissues may interfere with the effectiveness of subsequent sterilization processes resulting in infection. In addition, the remaining foreign matter introduced during subsequent invasive surgical procedures may cause an exothermic reaction that may interfere with healing.

It is preferred to use a mechanical cleaning procedure that has been identified in the clinical setting for cleaning purposes and that it is desirable to perform sterilization during or after the cleaning cycle. The chosen cleaning procedure should not only ensure that adequate cleaning is performed under exceptional circumstances and conditions, but also be able to produce satisfactory results under certain test and field conditions.

In addition to achieving a high level of cleaning performance, the cleaning system needs to adapt to the specific needs of specific medical instruments and devices. An ideal cleaning system may be a suitable cleaning medical instrument and device having long, narrow, inaccessible holes, such as those found on a flexible enclosure, as well as the inner surface of a separate modular instrument. In the case of sophisticated instruments that can no longer be separated in the future, adequate cleaning performance should also be obtained.

Various cleaning machines and related devices have been developed as medical instruments and devices.

US Pat. No. 3,640,295 to Peterson discloses a surgical instrument carrying case that can be used separately, separately from, or in combination with the ultrasonic cleaner and ultrasonic cleaner, which ultrasonic cleaning process It is contained within at least one sink and vibrable cradle that can carry the instrument case. Pumps and filters are provided as part of the ultrasonic cleaner to circulate the cleaning liquid in the sink of the ultrasonic cleaner and to remove particles and other substances from the fluid. Peterson's' 295 patent does not specify cleaning standards or quality.

US Patent No. 3,957,252 to Storz, assigned to the company name "Storz-Endoskop GmbH", discloses a device for cleaning medical instruments. Stoze's' 252 patent relates to support means provided for installing an ultrasonic oscillator for filling wash water in a conventional sink for use in cleaning medical instruments. The focus of this invention is to eliminate the need for independent special ultrasonic cleaning tanks.

Heckele's U.S. Patent No. 4,064,886, assigned to the company name "Riwoplan Medizin-Technische Einrichtungs-Gesellschaft GmbH", describes a holder device, a cylindrical cleaning container, a time control means for placing the holder device under a fixed time adjustment and a holder device. A cleaning enclosure device is disclosed that includes a rotatable underlay. The object of this invention is to perform rapid automatic cleaning and sterilization of the enclosure without damaging the enclosure. In addition, this invention does not specify the standard or quality of cleaning.

US Pat. No. 4,710,233 to Hohmann et al. Assigned to the company name “Siemens Aktiengesellschaft” discloses a method and apparatus for cleaning, disinfecting and sterilizing medical instruments in the order of the steps of the method performed in a single device. This invention discloses a complex method and apparatus. The steps of the method include pre-cleaning the instrument in a container containing a first fluid bath with ultrasonic energy for a time T1, followed by emptying the first fluid bath from the container, and then into a second fluid bath containing a cleaning agent and sodium chloride. Replacing it, cleaning and sterilizing the apparatus well by applying ultrasonic energy to the second fluid bath for a time T2 and circulating the second fluid bath through an electrolyte cell having a voltage applied to the electrode to produce an electrolyte material therein. Then emptying the second fluid bath and replacing it with a rinse bath, applying ultrasonic energy to the rinse bath, rinsing the instrument for a time T3 by circulating the second fluid bath through the electrolyte cell, and then emptying the rinse bath, And drying the appliance with heated air. Thus, Homan's 233 invention was designed to provide proper cleaning and sterilization of medical instruments, but this is accomplished by expensive and complex devices and methods.

Childers et al., U.S. Pat.No. 5,032,186, assigned to the company name "American Sterilizer Company," discloses a method and apparatus for cleaning or sterilizing hospital or laboratory materials. The invention includes the steps of loading items to be cleaned into a chamber, filling the chamber with a wash liquid to a predetermined level, and injecting the chamber under control with a steam or air-steam mixture while filling the chamber with the wash liquid (where steam Is injected in a turbulent fashion, causing a washing action and starting to heat the wash liquid), and continuously injecting steam into the chamber after filling the chamber to a predetermined level so that the items can be cleaned. After the washing step, the chamber is drained, the items are rinsed and the chamber is drained again. A sensor is used to monitor the operating parameters of the device. Sensors are used to regulate the operation of the spray nozzle and steam injector such that such steam is controllably injected into the chamber after a certain point while causing the cleaning action and filling the chamber with the cleaning liquid to begin heating the cleaning liquid. In addition, this invention does not provide a means to ensure proper cleaning.

British Patent Publication No. 2,248,188 to Parker et al., Assigned to the company name "Keymed Ltd.", discloses a method and apparatus for cleaning and sterilizing medical instruments. The method and apparatus of this invention are particularly suitable for cleaning and sterilizing enclosures. This method includes the steps of placing the instrument in an enclosure, a cleaning face for applying a cleaning solution to the surface of the instrument, a sterile face for applying a sterile solution to the surface of the instrument, a rinse face for applying a flushing solution to the surface of the instrument, a volatile liquid Applying the instrument to a purging phase that applies to the surface of the instrument and a drying phase that passes the drying gas over the surface of the instrument. The cleaning face is described as long enough to thoroughly clean both the exterior and the interior of the enclosure. In addition, the present invention does not specify means for ensuring proper cleaning.

None of the above devices and methods provide a means to ensure proper cleaning of a medical device or apparatus. Thus, there remains a need for improved apparatus and methods for monitoring the cleaning process of medical devices.

(Summary of invention)

Before a detailed discussion of the present invention has been made, reference is made herein to specific terms used broadly. Thus, as used herein, "sterilization" or "sterilize" may also include the meaning of sterilization. Likewise, "cleaning" and "cleaning liquid" as used herein may also mean rinsing or rinsing liquid.

The present invention relates to an apparatus and method that can monitor the cleaning process of a medical device and determine when the device is sufficiently cleaned so that the device can be sterilized.

Contaminant detectors that can be used alone or in combination with various detection techniques for monitoring cleaning are provided in the apparatus of the present invention. In general, detection techniques include ion-selective electrodes, conductivity, spectrophotometry, ion chromatography, capillary electrophoresis, high performance liquid chromatography, liquid chromatography, periodic voltage analysis, radioactivity, quartz crystal trace balance and other gravimetric techniques. , Infrared spectroscopy and other spectroscopic techniques.

The device of the present invention may use a detection technique that is suitable for the detection technique to detect the presence of contaminants on the surface of the medical device. Suitable detection techniques for detecting the presence of contaminants on the surface of the medical device can operate without contact with the surface of the device. Alternatively, a detection technique suitable for detecting the presence of contaminants on the surface of the medical device may operate via direct surface contacts. This approach uses the same physicochemical detection techniques as already mentioned for other attempts. However, the medical device itself is not monitored for the degree of cleaning. Rather, contaminant deposited standards are inserted into the device and monitored instead of the medical device itself. A correlation between the degree of cleaning of the contaminated device to be cleaned and the degree of cleaning of the contaminated standard can be established, so that when the standard is cleaned to a certain degree, sufficient cleaning of the device to be cleaned can be achieved.

Thus, according to one aspect of the invention, an apparatus for monitoring a cleaning process of a medical device is provided. The apparatus includes a cleaning chamber for receiving the instrument and for cleaning the instrument with a cleaning liquid. A contaminant detector is coupled to the cleaning chamber and is employed to indicate the amount of contaminants on the instrument. The contaminant detector is at least partially separated from the chamber to control access to the detector by the cleaning liquid. The contaminant detector can move and by moving this detector it can be produced in or outside the fluid in communication with the chamber. The contaminant detector may include an electrode located within the enclosure, where the enclosure is coupled to the chamber such that the cleaning liquid is adjustablely accessible to the enclosure.

According to another feature of the invention, a method of cleaning and sterilizing a contaminated medical device is provided. The method comprises the steps of: a) providing a cleaning chamber containing the contaminated device; b) providing a contaminant detector associated with the cleaning chamber; c) introducing a cleaning liquid into the cleaning chamber; d) cleaning the contaminated device in the cleaning chamber; e) exposing the detector to the cleaning liquid to measure the amount of contaminants removed from the contaminated device; f) determining that a sufficient amount of contaminants has been removed from the contaminated device so that the contaminated device can be sterilized; And g) sterilizing the contaminated device. Preferably, the detector is at least partially blocked from the cleaning liquid during step d). Exposing the detector to the cleaning liquid and isolating the detector from the cleaning liquid is accomplished by moving the detector in and out of the fluid in communication with the chamber or by adjusting the cleaning liquid to the enclosure by positioning the detector within the enclosure to the chamber. This can be done by enabling access.

According to another feature of the invention, an apparatus for monitoring a cleaning process of a contaminated instrument is provided. The apparatus includes a chamber for receiving and cleaning the instrument. The enclosure is in an adjustable fluid in communication with the chamber. The chemical source is coupled to the enclosure to provide a chemical that can react with the contaminants of the instrument to generate a detectable signal within the enclosure. A detector for detecting a signal is provided in this apparatus. Chemicals include Hg (SCN) ₂ , OPA (o-phthalic dialdehyde + triol), bromcresol purple (C ₁₂ H ₁₆ Br ₂ O ₅ S ₉ ), biuret reagent and microprotein-PR The apparatus may further comprise a light source for transmitting a light beam to the detector through the cleaning liquid in the enclosure The enclosure may be separated from the chamber by a valve. The second detector can be coupled to the inlet and the first detector and the enclosure can be coupled to the outlet.

According to another feature of the invention, a method of cleaning and sterilizing a contaminated medical device is provided. The method comprises the steps of: a) providing a cleaning chamber containing the contaminated device; b) providing a chemical source coupled to the enclosure in the adjustable fluid in communication with the cleaning chamber and containing a chemical that is capable of reacting with contaminants on the device to generate a detectable signal; c) introducing a cleaning liquid into the cleaning chamber; d) cleaning the contaminated device in the cleaning chamber; e) ejecting chemicals from the source into the enclosure; f) detecting a signal generated through the reaction between the chemical and the contaminant in the cleaning liquid to determine whether a sufficient amount of contaminant has been removed from the device; And g) sterilizing the device. Some of the cleaning liquid may be introduced into the enclosure before chemicals are discharged into the enclosure, and the enclosure may be separated from the cleaning chamber so that no fluid communication therein occurs substantially before the portion of the cleaning liquid is introduced. The signal can be colored or absorbed at specific wavelengths.

In accordance with another aspect of the present invention, an apparatus for monitoring a cleaning process of a medical device is provided. The apparatus includes a chamber for receiving and cleaning the instrument. Standards containing a predetermined amount of contaminants are located in the chamber or in an adjustable fluid in communication with the chamber. A detector adapted to indicate the amount of contaminants on the standard is coupled to the device. The apparatus may include a cleaning / rinsing system that may be adjusted to change the relative change efficiency in the devices of different locations. Standards can be positioned so that the instrument is cleaned more efficiently than this standard. The indication may be a signal such as the concentration of contaminants in the liquid used to clean the device, the electrical potential of the liquid used to clean the device, the conductivity, the transparency of a particular wavelength, or the color of the liquid used for cleaning. Preferably, the standard may comprise a surface covered with contaminants. Additional light sources may be provided that generate light of a predetermined wavelength that travels through the standard to reach the detector. The standard may be placed in an enclosure in an adjustable fluid in communication with the chamber. The enclosure can have a chemical source that can controllably release the chemical into the enclosure, where the chemical reacts with contaminants that are removed from or remain on the standard to generate a detectable signal. The detector may comprise an electrode located within the enclosure.

According to another feature of the invention, a method of cleaning and sterilizing a contaminated medical device is provided. The method comprises the steps of: a) providing a chamber for containing the contaminated device; b) providing a contaminated standard coupled to the chamber; c) introducing a cleaning liquid into the chamber; d) cleaning the contaminated device and the contaminated standard; e) measuring the amount of contaminants removed from the contaminated standard; f) determining that a sufficient amount of contaminants has been removed from the contaminated standard so that the contaminated device can be sterilized; And g) sterilizing the contaminated device. Preferably, the cleaning step includes exposing the standard to the cleaning environment more effectively or less effectively than the contaminated device is exposed, and the determining step includes determining whether the contaminated standard has been cleaned to a predetermined level. Include. Contaminated standards can be more contaminated or more difficult to clean than contaminated devices. The method may further comprise measuring the contaminant level of the cleaning liquid before the liquid is introduced into the chamber. Step e) comprises measuring (or comprising) inorganic contaminants such as inorganic electrolytes, alkali and alkaline earth salts, inorganic metal containing compounds and other inorganic compounds present in the body fluids to be in contact with the medical device, and / or include proteins, glycoproteins, Measuring organic contaminants such as lipoproteins, mucus, amino acids, polysaccharides, sugars, lipids, glycolipids, other organic compounds, microorganisms and viruses present in the body fluids to be in contact with the medical device. Measuring the amount of contaminants removed from the contaminated device can be performed by detecting contaminants remaining on the contaminated standard or contaminants removed from the contaminated standard and contained in the cleaning liquid. Preferably, the contaminated standard is placed in an enclosure in an adjustable fluid in communication with the chamber, and by adjusting the degree of fluid communication between the chamber and the enclosure, the relative cleaning efficiency of the chamber and the enclosure can be adjusted. Step e) may comprise measuring the contaminant level of the cleaning liquid in the enclosure.

In accordance with another aspect of the present invention, an apparatus for monitoring a cleaning process of a medical device is provided. The apparatus includes a cleaning chamber for receiving and cleaning the instrument, and a minimum first contaminant detector and a second contaminant detector employed to indicate the amount of contaminants removed from or left on the instrument. The first and second contaminant detectors can be placed in a fluid in communication with the cleaning chamber. The first and second contaminant detectors are ion-selective electrodes, conductivity, spectrophotometry, ion chromatography, capillary electrophoresis, high performance liquid chromatography, liquid chromatography, radioactivity, gravity, infrared spectroscopy, partial pressure measurement and turbidity Can be selected by measurement. One of the contaminant detectors can detect inorganic contaminants and the other can detect organic contaminants. One detector is located near the inlet of the cleaning chamber and the other detector is located near the outlet of the cleaning chamber. The apparatus further comprises a second chamber in the fluid in communication with the cleaning chamber and one detector is located in the second chamber in the cleaning chamber so that the measurement results from the two chambers are compared to evaluate the degree of cleaning. Can be used.

According to another feature of the invention, a method of cleaning and sterilizing a contaminated medical device is provided. The method comprises the steps of: a) providing a cleaning chamber containing the contaminated device; b) introducing a cleaning liquid into the chamber; c) cleaning the contaminated device in a cleaning chamber; d) measuring the amount of contaminants removed from the contaminated device with at least two detectors; e) determining whether a sufficient amount of contaminants has been removed from the contaminated device so that the contaminated device can be sterilized; And f) sterilizing the device. Step d) may comprise measuring the contaminant level of the cleaning liquid with the first detector before the cleaning step and measuring the contaminant level of the cleaning liquid with the second detector during or after the cleaning step. Step e) may comprise comparing the contaminant level of the cleaning liquid measured by the first detector with the contaminant level of the cleaning liquid measured by the second detector. If the difference between the two contaminant levels is within a predetermined range, a sufficient amount of contaminant is removed from the contaminated device. Step d) may comprise measuring, by one detector, inorganic contaminants such as inorganic electrolytes, alkali and alkaline earth salts, inorganic metal containing compounds and other inorganic compounds present in the body fluids to be in contact with the medical device, Detecting organic contaminants, such as proteins, glycoproteins, lipoproteins, mucus, amino acids, polysaccharides, sugars, lipids, glycolipids, other organic compounds, microorganisms, and viruses present in the body fluids to be in contact with the medical device can do. Measuring the contaminants removed from the contaminated device may be performed by detecting contaminants remaining on the contaminated device or contaminants removed from the contaminated device and contained in the cleaning liquid.

The apparatus of the present invention as discussed above may further comprise a vacuum pump connected to the chamber, which also serves as a vacuum chamber.

The device of the present invention as discussed above may further comprise a sterilization system.

In the process according to the invention, the sterilization step can be carried out by a gas phase sterilization process.

In the method according to the invention, the cleaning liquid comprises a liquid sterilizing agent, whereby the cleaning step and the sterilization step are performed simultaneously.

The process according to the invention may further comprise a vacuum drying step.

One feature of the present invention is to determine when the medical device is sufficiently cleaned to ensure that subsequent sterilization processes provide sterile products, such as having a sterility assurance level (SAL) of ^10-6 . . In other words, the probability that the device will not be sterilized is less than one million. In order to develop techniques that can accomplish these objectives, studies are being conducted to clarify some of the important relationships between microbial contaminated surfaces, surface deposition types and subsequent sterilization of medical devices.

The first experiment involved inoculating one million Bacillus stearothermophilus spores in saline (sodium chloride) in 100 μl of various concentrations of water onto stainless steel blades. Twenty blades were used for each concentration of saline solution evaluated. After overnight drying, the blades were subjected to a standard sterilization protocol in one sterilization cycle in a sterilization apparatus available from Advanced Sterilization Products, Irvine, CA. The sterilization protocol involves wrapping the blade twice with a CSR wrap and using the entire sterilization cycle at 6 mg / l hydrogen peroxide in a chamber derived from 59% hydrogen peroxide solution. The blade is then placed in TSB culture medium and incubated for 14 days at 55 ° C. to determine if any viable organisms remain. Each concentration of brine is evaluated by three replicates with a total of 60 blades. Here is the result:

The first number in each column represents the number of blades found to contain organisms that survive after exposure to the sterilization method. The second number in each column represents the number of blades evaluated in each trial. As the amount of brine in the surface deposits decreases, it can be seen that the less the number of surviving residual organisms, the more efficient the sterilization process is. Similar to surface deposits of varying amounts of fetal serum with varying amounts of fetal bovine serum, as well as surface deposits of varying concentrations of fetal bovine serum (FBS) naturally containing about 0.75% salt when undiluted The experiment was performed. The results of the experiments are as follows:

It can be seen that surface deposits consisting solely of fetal bovine serum, even when undiluted, contain 0.75% of salt and are substantially uninterrupted by subsequent sterilization in this particular experimental protocol. The presence of protein in the serum is believed to interfere with the formation of salt crystals during the drying process. These salt crystals can block the microorganisms and protect them from sterilization processes. Thus, a particular attempt is made in terms of obtaining a sterilization device during the simultaneous or subsequent sterilization process by the presence of a salt such as NaCl in the surface deposits on the medical device. Since the purpose of the present invention is to determine when the medical device is sufficiently cleaned to be sterilized, it is very important to monitor the concentration of salt during the cleaning process. In addition, tap water containing complex salts at relatively low concentrations is less challenging because no uniform crystals are likely to form.

Additional experiments simulating rinsing or cleaning processes were performed on contaminated deposited stainless steel (SS) blades or polytetrafluoroethylene (PTFE) plastic strips as models for stainless steel and plastic medical devices and instruments. These experiments clearly show some of the important relationships between the surface deposit (or contaminant) type and the release or cleaning rate during the simulated rinse or cleaning process.

A series of contaminant containing solutions was prepared with the composition as shown in Table 3.

RPMI tissue culture medium known in the art provides relatively high salt concentrations and low protein concentrations when combined with 10% FBS. Fractions of solution were deposited and dried on stainless steel surgical blades or small strips of polytetrafluoroethylene plastic. A simulated rinsing or cleaning process is then performed, and the pollutant release rate is monitored through a chloride ion specific electrode for sodium chloride (NaCl) or through spectroscopic techniques based on o-phthal dialdehyde (OPA) analysis for the entire protein. . Specific conditions and results for these experiments are as follows.

In a first experiment, 100 μl of sodium chloride solution was inoculated onto each SS blade. Eight blades were used for the experiment. Each blade was dried in an oven at 35 ° C. for 70 minutes and then at room temperature for 30 minutes. Eight vials were used to soak the blades, one for each blade. Each bottle contains 20 ml of deionized water. Soaking time ranged from 0-60 seconds. The amount of sodium chloride released into the deionized water was monitored by a chloride ion selective electrode. 1 illustrates the experimental results. 1 is a graph of sodium chloride release rate of sodium chloride inoculated stainless steel blade in deionized water at room temperature.

In a second experiment, 100 μl of albumin solution was inoculated onto each of the eight SS blades. Each blade was dried in an oven at 35 ° C. for 70 minutes followed by an additional 30 minutes at room temperature. Eight vials were used to soak the blades, one for each blade. Each bottle contains 20 ml of deionized water. The blades were soaked for 0-300 seconds and the amount of protein and sodium chloride released from each blade into deionized water was monitored by the appropriate technique. 2 is a graph of albumin and sodium chloride release rates of a stainless steel blade inoculated with albumin solution in deionized water at room temperature.

In a third experiment, 100 μl of RPMI tissue culture medium with 10% FBS was inoculated onto each of the eight SS blades. Each blade was dried in an oven at 35 ° C. for 70 minutes followed by an additional 30 minutes at room temperature. Eight vials were used to soak the blades, one for each blade. Each bottle contains 20 ml of deionized water. The release rate of sodium chloride and protein released from each blade into deionized water was monitored by the appropriate technique. 3 is a graph of sodium chloride and protein release rate of RPMI tissue culture medium + 10% FBS contaminated stainless steel blade in deionized water at room temperature.

In a fourth experiment, 100 μl of bovine fetal serum was inoculated onto each of the eight SS blades. Each blade was dried in an oven at 35 ° C. for 70 minutes followed by an additional 30 minutes at room temperature. Eight vials were used to soak the blades, one for each blade. Each bottle contains 20 ml of deionized water. The release rate of sodium chloride and protein released from the blade into deionized water was monitored by the appropriate technique. 4 is a graph of protein and sodium chloride release rates of fetal bovine serum inoculated stainless steel blade in deionized water at room temperature.

The results of the initial four release experiments showed that in all cases sodium chloride contaminants were removed from the SS blades before the protein containing contaminants. In addition, in all cases, the amount of time required to remove protein containing contaminants is no more than twice the time required to remove sodium chloride. In addition, in all cases, all blades were cleaned within 5 minutes by simply soaking in 20 ml of deionized water.

The next series of experiments examined the relationship between cleaning speed, cleaning solution composition, cleaning conditions and type of surface. In Experiments 5-8, the blood used was fresh, again calcified bovine blood, and was prepared by gently mixing 20 parts of whole blood of citric acid treated cows with 0.5 mol parts of calcium chloride solution at room temperature.

In a fifth experiment, the release rate of blood from a pair of blades was measured. Each set of blades contained 12 SS surgical blades (Bard Parker, size # 10). Five drops of blood were deposited on each blade. Each drop was 10 μl. The blade was dried as in the previous experiment. When starting to measure the release rate, the blade was placed on the bottom of a glass beaker (150 ml capacity) with a soaking solution inside. The soaking solution consisted of 100 ml of 1% SDS (sodium dodecyl sulfate) solution and 0.2 ml of 5M NaNO ₃ at 23 ° C., 200 RPM stirring rate. Agitation was achieved by using a small Teflon stirring paddle (blade size = ½ "x ½", 1/16 "width) rotated at constant speed by the mixer. The rate of sodium chloride and protein release from the blade was monitored by the appropriate technique above. 5 is a graph of sodium chloride and protein release rates of blood inoculated stainless steel blades in 1% SDS solution at a stirring rate of 23 ° C., 200 RPM.

In a sixth experiment, the release rate of blood from the 12 PTFE strips was measured. Five drops of blood were deposited on each strip (35 mm × 6 mm × 2 mm). Each drop was 10 μl. The strip was dried as in the previous experiment. When starting to measure the release rate, the strip was placed on the bottom of a glass beaker (150 ml volume) with a soaking solution inside. The soaking solution consisted of 100 ml of 1% SDS solution and 0.2 ml of 5M NaNO ₃ at 23 ° C., agitation speed of 200 RPM. The sodium chloride and protein release rates from the PTFE strips were evaluated by the appropriate technique above. 6 is a graph of sodium chloride and protein release rate of blood inoculated PTFE strips in 1% SDS solution at a stirring rate of 23 ° C., 200 RPM.

The results of the two experiments show that once again sodium chloride contaminants are released more easily than protein contaminants. Moreover, the time required to remove protein contaminants is not much longer than the amount of time required to remove sodium chloride contaminants. In addition, complete blood deposits are more difficult to remove than previous deposits, despite using 1% SDS solution and stirring the solution at 200 RPM. There is also a slight difference between the two surfaces of the SS blade to the PTFE strip.

The following experiments investigated the effects of stirring speed and temperature of the cleaning solution.

In a seventh experiment, the release rate of blood was measured at different stirring rates from a set of blades. Each set of blades contained 12 SS surgical blades (Size # 10). Five drops of blood were deposited on each blade. Each drop was 10 μl. The blade was dried as in the previous experiment. When starting to measure the release rate, a set of blades were placed in 100 ml of soaking solution at room temperature and exposed at different stirring speeds (0, 350, 700 and 1400 RPM). In addition, a pair of blades was exposed to 1400 RPM at 45 ° C. The soaking solution consisted of 100 ml of 1% SDS solution and 0.2 ml of 5M NaNO ₃ . FIG. 7 is a graph of protein release rate of stainless steel blades inoculated into blood in 1% SDS solution at 23 ° C., 45 ° C. and different stirring rates.

In an eighth experiment, the release rate of blood from a pair of PTFE strips was measured at two different temperatures. Each set contained 12 PTFE strips. Five drops of blood were deposited on each strip. Each drop was 10 μl. The strip was dried as in the previous experiment. When starting to measure the release rate, the strip was placed on the bottom of a glass beaker (150 ml capacity) with 100 ml of soaking solution inside. One set of strips was used for experiments conducted at 45 ° C. and another set was used for experiments performed at 23 ° C. No agitation was done for all batches. Protein release rate from the PTFE strip was evaluated by the appropriate technique. 8 is a graph of protein release rate of PTFE strips inoculated into blood in 1% SDS solution at 23 ° C. and 45 ° C. FIG.

The two experiments show that increasing solution agitation rates or temperatures can result in shorter cleaning times or faster release rates.

In summary, it has been found from the results of these release rate experiments that by correcting the release rate of various pollutants, it is possible to monitor the release of selected pollutants to ensure that proper cleaning is achieved. In most cases, cleaning times of up to 2-3 times the amount of time required to remove inorganic contaminants may be used to ensure that proper protein contaminant removal has occurred. In addition, temperatures of about 45 ° C. or less can be used efficiently to increase the cleaning rate. Agitation may also be used to increase the cleaning efficiency. Although the cleaning solution composition may affect the cleaning rate, in many cases hot water (eg 30-50 ° C.) may properly remove all contaminants.

One feature of the present invention is to provide a device for monitoring a cleaning process of a medical device. Preferably, the device can determine when it is sufficiently cleaned so that it can be sterilized. The device is capable of detecting inorganic and / or organic contaminants on medical devices or in liquids used in cleaning or cleaning monitoring methods or on standards covered with contaminants that can act as a surrogate indicator of cleanliness for medical devices. And a detector.

Inorganic contaminants are known to be present in the body, such as sodium chloride, potassium chloride, calcium chloride and other electrolytes such as alkali and alkaline earth salts, iron salts, and iron salts, and all other weapons that will come into contact with medical devices that require use after sterilization. Compound.

Organic contaminants are known to be present in proteins, glycoproteins, lipoproteins, mucus, amino acids, polysaccharides, sugars, lipids, glycolipids, and all other organic compounds that will come into contact with medical devices requiring use after sterilization. . Organic contaminants may include whole, partial, surviving, debilitating, or lifeless microorganisms that can come into contact with medical devices. Microorganisms include all Gram-positive bacteria, Gram-negative bacteria, intestinal and exogenous microorganisms, yeast, fungi and viruses.

The device of the present invention is in contact with intact items such as surgical instruments, some important items in contact with torn skin or mucous membranes such as enclosures, arthroscopy enclosures, dental instruments and some anesthesia instruments and intact skin It is suitable for monitoring the cleaning process of a wide range of medical devices containing noncritical items.

The liquid used in the cleaning process includes a cleaning liquid and a rinsing liquid. Individual liquids used alone for the purpose of monitoring cleaning can also be used and thus can be used in a device comprising a contaminant detector. The cleaning process includes an integrated system including a stand-up cleaning process, a cleaning process including a cleaning step followed by a sterilization step, and an integrated system including a cleaning process in which cleaning and sterilization occur simultaneously.

The device for monitoring cleaning may be integrated with the cleaning system or the cleaning and sterilization system of the medical device.

The contaminant detector of the device of the present invention may use various detection techniques alone or in combination to monitor cleaning. The data from one analyzer can be used to verify the reliability of the data from another analyzer. Contaminant detection techniques include two basic contaminant categories: (1) detection techniques suitable for detecting inorganic contaminants; And (2) detection techniques suitable for detecting organic contaminants. In many cases, however, contaminant detection techniques may be suitable for detecting both inorganic and organic contaminants.

Possible detection methods are shown below. It should be understood that other suitable contaminant detection techniques are not listed herein. The following illustrates useful techniques that can be used in the present invention.

A. Inorganic Contaminants (eg NaCl)

1. Ion Selective Electrode

1.1 Chloride Electrode Method

Principle: The chloride electrode consists of a vitreous, a reference solution, and a silver chloride / silver sulfide membrane. When the membrane is in contact with the chloride solution, the electrode potential develops across the membrane. This electrode potential is measured for a constant reference potential using a pH / mV / ion meter. The concentration of chloride ions corresponding to the measured potentials is described by the Nernst equation:

E = Eo-S log X

here,

E = measured electrode potential (mV)

Eo = reference potential (mV)

S = electrode slope

X = chloride ion concentration (M)

The detection range of the common chloride electrode is 1M to 5.0 x 10 ^-5 M.

1.2 Sodium Electrode Method

Principle: The sodium electrode consists of a vitreous, a reference solution and a sensing membrane. The sensing membrane has a liquid internal fill solution in contact with the exchanged lipophilic membrane and contains a sodium selective ion exchanger. When this membrane is in contact with the sodium solution, electrode potentials develop across the membrane. This electrode potential is measured for a constant reference potential using a pH / mV / ion meter. The concentration of sodium ions corresponding to the measured potentials is described by the Nernst equation:

E = Eo-S log X

here,

E = measured electrode potential (mV)

Eo = reference potential (mV)

S = electrode slope

X = sodium ion concentration (M)

The detection range of the common sodium electrode is from saturated state to 1.0 x 10 ^-6 M.

When used as a contaminant detector, the electrode probes can be placed directly within the cleaning chamber in contact with the cleaning liquid or rinsing liquid or separated from the cleaning chamber and placed inside a liquid conduit used to sample the cleaning liquid, rinsing liquid or cleaning supernatant. . In addition, more than one electrode probe may be used simultaneously. In the latter case, one probe may be placed continuously or intermittently or in single contact with fresh wash, rinse or cleaning supernatant. The second probe can measure the potential of the wash solution, rinse solution or cleaning supervision solution exposed to the contaminated medical device. The potential readings of the two probes can be compared and the device can be considered sufficiently cleaned when the two potential readings are substantially the same or within a few percent (eg 3%) of each other.

2. Conductive Method

Principle: Ions or electrolytes in solution can be measured and quantified by measuring the electrical conductivity of the electrolyte solution. The conductivity of the solution depends on the number of ions present and the mobility of the ions. Sodium chloride (NaCl) is a strong electrolyte and is fully ionized in solution. As a result of its complete ionization, the conductivity of the NaCl solution is proportional to the concentration of NaCl in the solution. Weak electrolytes, such as acetic acid, are not fully ionized in solution, and therefore have low conductivity, and when conducting a lot of ionization, the conductance to dilution is greatly increased. Molar conductivity (Λ) is defined as

Λ = k / c

here,

c: molarity of the added electrolyte

k: conductivity

The conductivity of the solution is generally measured by a probe containing two electrodes in accordance with a suitable electrical circuit such as Wheatstone Bridge for measuring the current between the electrodes. The conductivity of the solution is derived from the total number of ions in the solution derived from all strong and weak electrolytes present.

When used as a contaminant detector, the conductive probe can be placed directly in the cleaning chamber in contact with the cleaning liquid or rinsing liquid or separated from the cleaning chamber and placed inside a liquid conduit used to sample the cleaning liquid, rinsing liquid or cleaning supernatant. . In addition, more than one conductive probe may be used simultaneously. In the latter case, one probe may be placed continuously or intermittently or in single contact with fresh wash, rinse or cleaning supernatant. Such probes can act to provide a controlled conductivity reading for contaminant free liquids. The second probe can measure the conductivity of the wash solution, rinse solution or cleaning supervision solution exposed to the contaminated medical device. The conductive readings of the two probes can be compared and the device can be considered sufficiently cleaned when the two conductive readings are substantially the same or within a few percent (eg 3%) of each other.

3. Spectrophotometric Measurement Method

3.1 Chloride Ion Reagent

2Cl (-) + Hg (SCN) ₂ → HgCl ₂ + 2SCN (-)

SCN (-) + Fe ⁺³ → Fe (SCN) ⁺⁺

(Reddish brown, 460 nm)

Principle: Chloride ions react with chloride reagents to form Fe (SCN) ⁺⁺ ions (reddish brown) with maximum absorbance at 460 nm. Preferably, an automated calorimeter or photometric autotitrator is used by spectrophotometric techniques based on the generation of colored species from the analyzed contaminants.

4. Ion Chromatography

Principle: relates to the separation of substrates by their differential migration on sheets immersed by an ion exchange column or ion exchanger. Ions (anions or cations) are separated based on ion exchange reactions that are characteristic of each type of ion. Common detectors for ion chromatography are conductivity measurements, UV and electrochemical detectors. Ion chromatography can detect chloride ions dissolved in water when the concentration is in the detection limit range of 0.02 mg / L to 80 mg / L.

Preferably, automatic ion chromatography is used when using ion chromatography for contamination detection.

5. Capillary Electrophoresis

Principle: Electrophoresis is the movement of charged jaws in an electric field. Capillary electrophoresis uses capillaries. The main advantage of using capillaries for electrophoresis is enhanced thermal dissociation which allows the use of high potentials for separation. The use of a high potential field leads to extremely efficient separation resulting in a dramatic reduction in analysis time.

6. High Performance Liquid Chromatography (HPLC)

Principle: The separation of the components of the solution followed by the different migration of the solute in the liquid flowing through the column packed with special solid impellers. Peptides (by reverse phase chromatography), proteins and enzymes (hydrophobic, chromatographic exclusion mode), amino acids and inorganic and organometallic compounds may be present in the isolate. There are several detectors that can be selected for the HPLC system. These are UV-VIS absorption, IR absorption, fluorescence analysis, refractive index, conductivity measurement, electrochemical and radioactivity detectors. Depending on the simple stagnation phase type, various separation columns can be selected. Common columns are affinity, gel-filtration and ion-exchange columns.

(1) Affinity Medium:

Successful affinity separation requires the biospecific ligand to be covalently bound to the bed material, matrix by chromatography.

(2) gel filtration

Separation is based on differences in size and / or shape of analyte molecules and governs the analyte's approach to the pore volume inside the column packed particles.

(3) ion-exchange

This method involves the interaction of solutes with changed groups of packing material, followed by elution using an aqueous buffer of greater ionic strength or change in pH.

7. Conclusion

Any of many different techniques can be used to monitor inorganic contaminants. One convenient product for electrolyte testing is the "MultiPLY" integrated multiple sensor available from Daile International, Newark, Delaware.

B. Organic Contaminants (eg Proteins)

1. Spectrophotometric measurement (UV in visible light, wavelength of 190-900 nm)

1.1 OPA Method

Protein-NH ₂ + o-phthalic acid dialdehyde + thiol → 1-alkylthio-2-alkylisoindole

                  (OPA) (fluorescence, 340 nm)

Principle: The amino group of a protein reacts with the aldehyde group of OPA in the presence of a thiol component (N, N-dimethyl-2-mercaptoethylammonium chloride) to form a fluorescent compound (1-alkylthio-2-alkylisoindole) . The fluorescent compound has a maximum absorbance at 340 nm.

1.2 Albumin Reagent Method

Albumin + Bromcresol Purple → Stable Complex

(C ₂₁ H ₁₆ Br ₂ O ₅ S ₉ FW = 540.24) (610 nm)

Principle: Bromcresol Purple binds quantitatively with serum albumin to form a stable complex and can be detected at 610 nm. The amount of complex produced is linearly proportional to the albumin concentration in the solution.

1.3 Lori Micro Way

Principle: The diluted burette reagent reacts with peptide bonds to produce a purple-blue complex. The color of such complexes can be further enhanced by adding phenolic reagents. The increase in absorbance read at 550-750 nm is used to determine the protein concentration in the sample.

1.4: Microprotein-PR ^TM Method

Principle: When the pyrogallol complex (in the microprotein-PR reagent) binds to the amino group of the protein, the absorbency of the reagent shifts. The increase in absorbance at 600 nm is directly proportional to the concentration of protein in the sample.

2. Liquid Chromatography or High Performance Liquid Chromatography (HPLC)

Principle: same as in the measurement of inorganic species

3. Periodic Voltage Measurement Analysis

Principle: When materials (metals, polymers, etc.) come into contact with blood proteins, a protein (mostly fibrinogen) layer forms at the interface within seconds. As a result of protein adsorption, the addition of protein to a protein-free solution can alter the action of the current density-potential (I vs V) of the metal electrode in periodic voltage measurements. For example, the I-V action of high purity copper alloys (2% zinc) is altered by adding proteins (albumin, fibrinogen, etc.) to the supporting phosphate-saline electrolyte.

4. radiation activity

Principle: Proteins are labeled with radioactive isotopes, such as Technicium 99 or iodine 125, and the radioactivity of the solution is measured to determine the amount of protein present. For example, protein fibrinogen was labeled with ¹²⁵ I using a 2-fold molar excess of iodine monochloride. The biological properties of the labeled fibrinogen are not affected by this labeling method. The concentration of fibrinogen in the solution is directly proportional to the radioactivity (or intensity of gamma radiation) of the solution containing the labeled fibrinogen.

5. Quartz Crystal Microbalance (QCM) Method

Principle: Quartz crystal microbalance is a mass sensitive detector based on a vibrating quartz wafer. The reaction of QCM is extremely sensitive to mass changes at the solid-solution interface. When gold-coated quartz crystals come into contact with blood proteins, a protein layer forms at the interface within a few seconds. Such small mass changes can be easily detected by QCM. The increase in mass (or decrease in the frequency of vibration) for the quartz crystal is directly proportional to the protein concentration in the solution.

6. FTIR spectroscopy (transmission and ATR)

Fourier Transform Infrared (FTIR) spectroscopy can be used to identify and quantify the proteins in the mixture both in solution as well as on the surface. Transfer of Aqueous Protein Solution FTIR studies indicate the identity and amount of proteins present. Attenuated Total Reflectance (ATR) FTIR studies of protein-deposited surfaces can determine the identity and amount of proteins on the surface.

7. Electrophoresis

Principle: Electrophoresis is the movement of species in the electric field. Generally, protein molecules pick up hydrogen ions in an acid solution to be positively charged. By varying the pH of the electrophoretic medium, the rate of protein can also be altered. For a given protein, if pI (the pH when the protein is electrically neutral) is less than pH, the change may be negative and migration will occur towards the positive electrode. Protein components with pI> pH will be positively charged and migration occurs in the opposite direction.

8. Capillary Electrophoresis

Principle: same as in the measurement of inorganic species

Extra-cost techniques for detecting inorganic and organic contaminants include dislocation measurements, in particular dislocation measurement autotitrators and techniques for detecting the transparency of particles or solutions in solution. The transparency of the solution can be measured by a turbidity meter consisting of a turbidity sensor with a flow cell. Turbidity meters typically operate by photovoltaic cells and provide electrical signals that are easily integrated with other systems, such as cleaning control systems. Alternatively, the transparency of the solution can be determined through measurements of the color, reflectance, absorbance, transmittance, etc. of the liquid. Laser systems using optical fibers for transmission from the laser and from the sample to the detector may also be used to evaluate the transparency or many other properties of the solution.

Preferably, the apparatus of the present invention employs a detection technique that detects contaminants when the detection technique is suitable for detecting the presence of contaminants in the liquid used in the cleaning process. Preferably, the liquid is selected from the group consisting of a cleaning liquid and a rinsing liquid during the cleaning process.

The apparatus of the present invention may use a detection technique where the detection technique is suitable for detecting the presence of contaminants on the surface of the medical device. Preferably, a detection technique suitable for detecting the presence of contaminants on the surface of the medical device operates without contacting the surface of the device. For example, by using fiber optics technology combined with reflectance spectrophotometry, anyone can directly monitor surface cleaning. Alternatively, a detection technique suitable for detecting the presence of contaminants on the surface of the medical device may operate via direct surface contact. That is, from a detection technique, the probe may be in physical contact with the surface of the medical device, thereby determining the amount of contaminants present on the surface to determine and quantify the state of transparency of the medical device. In most cases, the physical contact between the probe and the device is temporary. A suitable technique for this particular application is attenuated total reflectance (ATR) spectroscopy. The ATR method uses a crystal that transmits sensing radiation directly to the surface of the sample to be monitored. The crystal is in physical contact with the surface of the sample. ATR spectroscopy can be used with infrared (UV) absorption spectrophotometry as well as infrared spectroscopic techniques. ATR-UV technology uses sapphire crystals as sampling probes. Fourier transform infrared spectroscopy can likewise be used to determine appropriate ATR.

Alternatively, indirect detection techniques can also be used. This approach uses the same physicochemical detection techniques and methods as already mentioned for other attempts. However, the medical device itself does not monitor for the degree of cleaning. Rather, contaminant deposited standards are inserted into the device and monitored instead of the medical device itself.

The contaminant detector can use a continuous sampling of the surface of the liquid or medical device or the contaminant covered standard, or can use a periodic or single sampling of the liquid or device or standard. Periodic sampling may be performed at uniform or non-uniform (ie random) intervals. The number of intervals should be as small as in a single sampling. A single sampling interval can survive under circumstances where the cleaning process takes place over a sufficient time to highly ensure that enough cleaning has occurred to allow the device to be sterilized later. However, preferably two or more sampling intervals are used by the contaminant detector to assess the amount of cleaning performed. More preferably, three or more sampling intervals are used. More preferably, four or more sampling intervals are used by the detection technique.

The ion-selective electrode method is used in contaminant detectors because of its relative sensitivity and specificity for measuring related compact probes, durability of the probe, ease of use, real-time measurement capability and electrical basis of the operation as well as related electrolytes such as sodium and chloride. Is preferred. Electrode potential measurements can be made continuously or intermittently and can be easily integrated with a conditioning system for cleaning or cleaning and sterilization devices. An adjustment system for adjusting the cleaning process may be part of the present invention.

Conductive methods are preferred for use in contaminant detectors for the same reasons as given for the ion-selective electrode method.

Another feature of the present invention is to provide a method of monitoring a cleaning process of a medical device, the method comprising measuring a contaminant removed from the medical device by the device of the present invention comprising a contamination detector.

Preferably, the method includes the additional step of measuring when the device is sufficiently cleaned to be sterilized.

Preferably, the device of the present invention is selected from the group consisting of an important item introduced into sterile tissue, a slightly important item in contact with ruptured skin or mucous membranes, and a non-important item in contact with intact skin. More preferably, an important item introduced into sterile tissue is a surgical instrument. More specifically, some important items in contact with ruptured skin or mucous membranes include enclosures, arthroscopy enclosures, dental instruments, and anesthetic instruments.

Preferably, the method of the present invention uses an apparatus comprising a contaminant detector, wherein the contaminant detector utilizes a detection technique capable of detecting inorganic contaminants and / or organic contaminants. The inorganic contaminants are selected from the group consisting of inorganic electrolytes, alkali and alkaline earth salts, inorganic metal containing compounds and other inorganic compounds present in the body that will be in contact with the medical device. Organic contaminants are selected from the group consisting of proteins, glycoproteins, lipoproteins, mucus, amino acids, polysaccharides, sugars, lipids, glycolipids, and other organic compounds present in the body that will come into contact with microorganisms and viruses.

Detection techniques used in the methods of the present invention include ion-selective electrodes, conductivity, spectrophotometry, ion chromatography, capillary electrophoresis, high performance liquid chromatography, liquid chromatography, radioactivity, gravity, infrared spectroscopy, partial pressure measurements And turbidity measurement.

The cleaning process monitored in the method of the invention comprises an independent cleaning process comprising at least one cleaning step, a cleaning process comprising at least one cleaning step followed by a sterilization step and a cleaning process in which both cleaning and sterilization occur simultaneously Is selected from.

A device comprising a contaminant detector used in the method of the present invention may be used by detecting contaminants on the device or by detecting contaminants in a liquid used in a cleaning or cleaning monitoring process or on a contaminated standard that is an indicator of cleanliness to the device. Measure the contaminants removed. Preferably, the liquid used in the cleaning process is a cleaning liquid.

The method of the present invention wherein the liquid is a cleaning liquid and the detection is made on contaminants in the liquid

(a) detecting contaminants in the liquid prior to the cleaning process; And

(b) detecting contaminants in the liquid during and after the cleaning process.

The method further comprises determining if the contaminant of step (b) is substantially the same as the contaminant of step (a), wherein the contaminant detected in step (b) is the contaminant detected in step (a) If substantially the same as, the device is considered to be sufficiently cleaned to be sterilized.

The amount of contaminant detected in one step may be considered to be substantially equal to the amount of contaminant detected in another step if both values are within an acceptable range. In many cases, the acceptable range can be up to 10% difference and more preferably within 3-5%.

In the above method, if the contaminant measured in step (b) is not substantially the same as the contaminant measured in step (a), the cleaning step or the rinsing step or all the steps of the cleaning process may be Repeat until substantially the same as the contaminant measured in step (a).

One embodiment of a monitoring device for the cleaning process of a medical device or instrument comprising a contaminant detector based on an ion-selective electrode is illustrated in FIG. 9. 9 illustrates a device 10 containing a cleaning chamber 20 for cleaning medical devices and instruments, such as medical device 22 having lumens and surgical instruments 24. The cleaning chamber 20 may be used for sterilization. The cleaning chamber 20 has a liquid outlet 40 with a valve 41 and a liquid inlet 45 with a valve 46. The liquid outlet 40 and the liquid inlet 45 are used to transport the wash or rinse liquid outside the wash chamber 20 and back to the chamber 20. The liquid outlet 40 is connected to a liquid conduit 50 which is again connected to the liquid pump 60 via the valve 41. The liquid conduit 50 transports the washing liquid or the rinsing liquid from the washing chamber 20 to the pump 60. The pump 60 pumps the washing liquid or the rinsing liquid from the washing chamber 20 to the liquid conduit 55 through the liquid outlet 40, the valve 41 and the liquid conduit 50. The liquid conduit 55 returns the liquid to the wash chamber 20 through the valve 46 and the liquid inlet 45. The liquid conduit 55 is also connected to the liquid conduit 58 containing the valve 57 and the liquid inlet 56. Liquid inlet 56 is used for the inlet of any fluid used in the washing or rinsing process. For example, the liquid inlet 56 allows the inlet of fresh wash, rinse or cleaning supernatant to the conduit 55 so that the potential reading can be taken by the electrode probe 70 placed inside the conduit 55. . The cleaning chamber 20 also contains a liquid outlet 44 connected to the valve 47. The valve 47 is connected to a conduit 54 which is connected again to the drain outlet 59. The liquid outlet 44 and the connected portion are used to drain the chamber 20 after a wash or rinse cycle.

The electrode probe 70 is used for contamination detection in a washing liquid or a rinsing liquid. The electrode probe 70 contains a first electrode 72 and a second electrode 74. The liquid flowing through the conduit 55 passes by the first electrode 72 and the second electrode 74. Ions in the liquid produce a current that is transmitted to electrical circuit 80 through electrical cable 76 and electrical cable 78 for the electrode detector. The electrical circuit 80 is connected to the wash control system 30 via an electrical connection 90. The wash control system 30 is directly connected to the wash chamber 20 and controls all aspects of the wash process.

Using the device of the invention illustrated in FIG. 9, the method of the invention for monitoring the cleaning process of a medical device operates as follows: All valves are initially in the closed position. When the valve 57 is open, fresh cleaning wash water or rinse water flows from the wash water or rinse water source (not shown) to the inlet 56. Electrode potential readings are initially obtained by electrode probe 70 of a cleaning wash or rinse solution that does not contain any contaminants. In this embodiment of the method of the invention, the potential reading is obtained from a cleaning wash liquid. This represents a time zero potential reading. The valve 46 is then opened to introduce wash water into the chamber 20 and fill it to prepare for the wash cycle. Alternatively, valves 46 and 57 can be open at the same time, so that a time zero reading can be taken while filling chamber 20. The time zero reading may be taken during the wash cycle if the desired valves 46 and 57 are closed and a wash cycle is initiated. The cleaning cycle runs over a time interval determined by the type of medical device and instrument present. Typically, this time interval is less than about 1 hour. Preferably, this time interval is less than about 30 minutes. More preferably, this time is less than about 15 minutes. At the end of the wash cycle, the valve 47 is opened and dirty wash water flows out of the chamber through the outlet 59. The valve 47 is closed after the chamber is empty. Once the valves 45 and 57 are open again, fresh rinse water is introduced into the chamber 20. After the chamber 20 is filled, the valves 45 and 47 are once again closed. Subsequently, a rinse cycle is performed. This cycle is generally the fraction of or equal to the wash cycle. One or more potential readings are taken from the rinse solution during or at the end of the rinse cycle. This opens the valves 41 and 46 simultaneously and pumps to pump the rinsing liquid into the conduits 50 and 55 until the rinsing liquid in contact with the electrode probe 70 is equal to the rinsing liquid inside the chamber 20. By turning on 60. If the potential of the rinse liquid following the wash cycle is substantially equal to the time zero potential reading, appropriate cleaning was achieved. Otherwise, the rinse cycle or wash cycle is repeated until the potential reading of the rinse solution achieves the desired value. In this step, the medical device 22 and the instrument 24 inside the chamber 20 may be sterilized in the second step of the two step sequential cleaning and sterilization method.

Another embodiment of a device for monitoring the cleaning process of a medical device or instrument including a contaminant detector based on an ion-selective electrode is illustrated in FIG. 10. FIG. 10 illustrates a device 11 containing a cleaning chamber 20 for cleaning medical devices and instruments, such as medical device 22 having a lumen and surgical instrument 24. The cleaning chamber 20 may be used for both cleaning and sterilization. Cleaning and sterilization can occur simultaneously or sequentially. Preferably, the cleaning step is performed before the sterilization step inside the chamber 20. The cleaning chamber is connected to a water source (not shown) and has a water inlet 53 connected to the valve 43 through the valve 52 and the conduit 51. The valve 43 is directly connected to an inlet 42 which is guided directly inside the cleaning chamber 20. The cleaning chamber 20 also has water outlets 44 and 48. The water outlet 44 is connected to the valve 47 and then to the conduit 54 which is led to the drain outlet 59 of the water. The water drain outlet 59 is mainly an outlet of dirty water used to purge dirty water from the washing chamber 20. The water outlet 48 is connected to the valve 49 and then to the conduit 61 which is guided to the valve 62. The valve 62 is led to the rinse water outlet 63. Conduit 51 in the water inlet line contains a first electrode probe 64 having a first electrode 65 and a second electrode 66. The first electrode 65 is connected to the electric cable 67, and the second electrode 66 is connected to the electric cable 68. Electrical cables 67 and 68 are led from the electrode probe 64 to an electrical circuit 31 that includes a cleaning or cleaning and sterilization control circuit as well as an ion selective electrode electrical circuit. Similarly, the second electrode probe 71 lies in the rinse water outlet conduit 61 between the valves 49 and 62. The electrode probe 71 has a first electrode 73 and a second electrode 75. Electrodes 73 and 75 are connected to electrical cables 77 and 79, respectively. Electrical cables 77 and 79 are directly connected to electrical circuit 31.

The method of the invention for monitoring the cleaning process of a medical device using the device of the invention illustrated in FIG. 10 operates as follows: valves 52 and 43 of the water inlet conduit 51 are opened and the chamber 20 is opened. Water begins to flow through the water inlet 42 into the cleaning chamber 20 until) is sufficiently filled for the cleaning cycle. This water is fresh, clean and unpolluted. The potential reading is obtained from this water by the electrode probe 64, and the electrical circuit 31 stores this reading. The valves 52 and 43 are then closed. The first cleaning cycle is performed in the cleaning chamber 20. This cleaning cycle is generally less than about 1 hour. Preferably, the cleaning cycle is less than about 30 minutes. More preferably, the cleaning cycle is less than about 15 minutes. The valve 47 is opened at the end of this first cleaning period. Dirty wash water is discharged from the chamber 20 through the outlet 44 after the valve 47 is opened. The valve 47 is closed after all dirty washing water is discharged from the washing chamber 20. Thereafter, the valves 53 and 43 are once again opened and the clean fresh rinse water begins to flow into the cleaning chamber 20 through the inlet port 42. A second potential reading of clean fresh rinse water flowing into the chamber may be taken by the first electrode probe 64. The valves 52 and 43 are then closed and a rinse cycle in the chamber 20 is started. This rinse cycle is generally less than about 1 hour. Preferably, the rinse cycle is less than about 30 minutes. More preferably, the rinse cycle is less than about 15 minutes. At the end of the rinse cycle, the valves 49 and 62 in the rinse water outlet line 61 are opened to allow rinse water to flow out of the cleaning chamber 20 past the second electrode probe 71. The potential reading is taken by the electrode probe 71 and sent to the electrical circuit 31. The electric circuit 31 is used to compare the potential of the rinsing water taken by the electrode probe 71 with the potential of the fresh and clean rinsing water taken by the electrode probe 64. If these two values are substantially equal, they are equal to or within a few percent of each other and no longer require further washing and rinsing. Once the valves 49 and 63 are closed, all rinse liquid is withdrawn from the chamber 20. However, if the two readings are not substantially equal in absolute value, an additional rinse step is initiated and performed as before. The second rinse cycle may be a fraction of the duration of the first rinse cycle or the same as the duration of the first rinse cycle. The potential reading is taken as before during the first rinse cycle, and the potential reading of the rinse solution is compared with the potential reading of a fresh, clean rinse solution after contact with the medical device and the instrument. Once these two readings are substantially the same, proper cleaning takes place and no further cleaning and rinsing is needed. In this step, the medical device 22 and the instrument 24 inside the chamber may be sterilized in a second step of a two step sequential cleaning and sterilization process. The chamber 20 may then be opened through a door (not shown), and the device 22 and instrument 24 may not be used.

Another embodiment of an apparatus for monitoring a cleaning process of a medical device or instrument comprising a contaminant detector based on an ion-selective electrode is illustrated in FIG. 11. 11 illustrates a device 12 containing a chamber 20 for cleaning medical devices and instruments, such as medical devices 22 having lumens and surgical instruments 24. The cleaning chamber 20 may be used for sterilization. Sterilization can occur simultaneously with the cleaning or after the cleaning step. The device 12 contains all parts of the device 11 illustrated in FIG. 10 except for the outlet 48, the valve 49, the valve 62, the conduit 61 and the rinse water outlet 63. . The device 12 operates in much the same way as the device 11 illustrated in FIG. 10. However, in the case of the apparatus 12 illustrated in FIG. 11, all rinse and wash liquid exits the wash chamber 20 through the outlet 44. Otherwise, all the steps of the method of the present invention used in the apparatus 11 as illustrated in FIG. 10 and monitoring the cleaning process already described are applied to the apparatus 12 illustrated in FIG. Once again, the second electrode probe 71 will take a potential reading of the rinse solution after contact with the medical device 22 and the instrument during or after the rinse cycle following the wash cycle. However, in this particular embodiment, these readings are obtained inside the cleaning chamber 20 rather than inside the conduit 61 as in the device 11 illustrated in FIG. 10. The main advantage of the device 11 as illustrated in FIG. 10 is the placement of the second electrode probe 71 inside the conduit 61. By disposing the second electrode probe 71 inside the conduit 61, the second electrode probe 71 is completely prevented from being excessively contaminated by contaminants. This ensures that electrode probe 71 will repeatedly perform potential readings accurately and precisely. In some cases, however, it is not necessary to place the second electrode probe 71 inside a separate conduit 61. Thus, the apparatus 12 illustrated in FIG. 11 is useful for some cleaning applications, and in particular contamination by the contaminants of the electrode probe 71 is known to be not a problem.

The devices illustrated in FIGS. 10 and 11 may be further modified to include, for example, a detector for detecting inorganic contaminants and a detector for detecting organic contaminants. The device may have a second chamber in an adjustable fluid in communication with the chamber 20, and the detectors may be placed in the second chamber. Contaminated standards may also be provided in the second chamber, for example, and the cleaning conditions and contaminant coverage for the contaminated standards are determined to serve to indicate the cleanliness of the standards to indicate the completion of cleaning of the device to be cleaned. .

12 illustrates another embodiment of a device for monitoring the cleaning process of a medical device or instrument including a contaminant detector based on ion-selective electrodes. FIG. 12 illustrates a device 13 containing a cleaning chamber 20 for cleaning medical devices and instruments, such as medical device 22 having a lumen and surgical instrument 24. As in other embodiments, the cleaning chamber 20 may be used for sterilization. The cleaning chamber 20 has a water inlet 42 connected to a water inlet conduit 51 via a valve 43. The water inlet conduit 51 is connected to the water inlet 53. The water inlet 53 is connected to a water source (not shown). The cleaning chamber 20 also has components 44, 47, 54 and 59 arranged in the same manner as shown in FIGS. 10 and 11, connected and having a water drainage function. This embodiment of the inventive device illustrated in FIG. 12 has a single electrode probe 70 having a first electrode 72 and a second electrode 74. Electrodes 72 and 74 are connected to electrical cables 76 and 78 respectively. Electrical cables 76 and 78 are connected directly to electrical circuit 31. The electrical circuit 31 performs the same function as described for the apparatus of the present invention illustrated in FIGS. 10 and 11. The electrode probe 70 rests inside a small water reservoir 81 that lies just below the water inlet 42. The water reservoir 81 is designed to capture the initial small volume of water that flows into the cleaning chamber 20. This allows a potential reading of fresh, clean wash water to be taken before contacting the medical device 22 and the instrument 24. The reservoir 81 has a reservoir outlet and an inlet 82 connected to the reservoir outlet and the inlet conduit 83. The reservoir outlet and inlet conduits 83 contain the reservoir outlet and inlet valve 84 and the reservoir drain outlet and inlet 85.

The method of the present invention for monitoring the cleaning process of a medical device, using the device of the present invention illustrated in FIG. 12, operates as follows: valve 43 is opened and fresh and clean water or other cleaning or rinsing fluid is applied. It flows through the inlet 42 into the cleaning chamber 20. The water reservoir 81 is charged by the electrode probe 70 to take a potential reading of fresh and clean water. This potential reading is stored in the electrical circuit 31 as the control potential reading. Water continues to flow through the inlet 42 into the cleaning chamber 20 and fills the reservoir 81. The reservoir valve 84 is open. Water then flows out of reservoir 81 into reservoir chamber 20 through reservoir conduit 83 and reservoir drain outlet and inlet 85. The cleaning chamber 20 is sufficiently filled with washing water so that the cleaning cycle can begin. The reservoir valve 84 is closed and the wash cycle is initiated as described in the method of the invention using the apparatus of the invention illustrated in FIGS. 10 and 11. Prior to the commencement of the cleaning cycle, valves 43 and 47 are closed such that liquid no longer flows to or drains from the cleaning chamber 20.

At this point, the electrode probe 70 may be wholly or partially separated from the dirty cleaning liquid in the chamber 20. This can be accomplished by a number of routes. For example, the reservoir 81 is filled with fresh wash solution, and the electrode probe 70 is immersed in the fresh wash liquid while cleaning is performed in the chamber 20, thereby causing the electrode probe to be contaminated by dirty wash solution. Protected from In other embodiments, the electrode probe 70 may be moved to or in no contact with the liquid. Alternatively, the reservoir 81 may be covered with a movable cap 91 during the cleaning process. An enclosure or a second chamber may be provided that is manufactured in an adjustable fluid in communication with the chamber 20 and the detector may be placed within the enclosure. Thus, fluid communication between the chamber 20 and the enclosure during the cleaning process is interrupted by, for example, a valve, and fluid communication is reestablished when measuring the concentration of contaminants in the wash liquid.

At the end of the cleaning cycle, dirty wash water flows out of the cleaning chamber 20 through the outlet 44 and into the drain outlet 59 through the outlet 47 which is open for that purpose. The valve 47 is then closed and fresh rinse liquid flows through the inlet 53 into the wash chamber 20 and through the valve 43 opened for that purpose to the inlet 42. Once again, the rinse liquid flows into the reservoir 81 to fill the reservoir and then to fill the chamber 20 during the rinse cycle in the same process as previously described. The valve 43 is closed and the rinse cycle takes place as already described in the method of the invention using the apparatus of the invention illustrated in FIGS. 10 and 11. The valve 84 is opened and the rinse liquid flows into the reservoir 81. Alternatively, the level of rinse liquid inside the chamber 20 may be higher than the top of both sides of the reservoir 81 and may fill the reservoir 81 with the rinse liquid. In this manner, an accurate potential reading of the rinse solution inside the reservoir 81 can be taken so that it represents a rinse solution inside the wash chamber 20. This second potential reading is compared to the potential reading of a fresh, clean rinse solution. The comparison of the potential readings is performed exactly as already described herein, and the measurement is made when sufficient rinsing and / or cleaning is done and additional rinsing or washing or rinsing cycles are required.

FIG. 13 illustrates another embodiment of a device for monitoring a cleaning process of a medical device or instrument including a contaminant detector based on ion-selective electrodes. FIG. 13 illustrates a device 14 once again containing a cleaning chamber 20 for cleaning or sterilizing and sterilizing previously described medical devices and instruments. All parts of the device 14 illustrated in FIG. 13 are identical to those described for the same numbered parts as in the device 13 illustrated in FIG. 12 except for parts 30, 80 and 90.

Parts 30, 80, and 90 are identical, identically connected, and function the same as parts 30, 80, and 90 illustrated in FIG. 9. Part 30 is a wash control system. Component 8 is an electrical circuit for an electrode detector. The electrical circuit 80 is connected to the wash control system 30 via an electrical connection 90. The component 31 illustrated in FIG. 12 performs the same function as the components 30, 80 and 90 illustrated in FIGS. 9 and 13.

The reservoir 81, reservoir outlet and inlet 82, reservoir outlet and inlet valve 84, reservoir outlet and inlet conduit 83 and reservoir drain outlet and inlet 85 illustrated in FIG. Not used in the device 14 illustrated in FIG. Apparatus 14 maintains a small volume of wash or rinse solution such that reservoir 81 and associated outlet and inlet parts 82-85 take a potential reading and are not used to sequentially discharge it. The method of the present invention is performed in the same manner as the device 13 of FIG. All potential readings are taken directly from the liquid inside the chamber 20 instead. Second probe 99 or more probes may be used to monitor for further contaminants.

FIG. 14 illustrates a device 15 containing a cleaning chamber 20 for cleaning or for cleaning and sterilizing the medical device 22 and the instrument 24 as already described. The device 15 also has an enclosure 102 coupled to the chamber 20. Enclosure 102 is placed in an adjustable fluid in communication with chamber 20. Preferably, chamber 20 and enclosure 102 are separated by valve 104. Enclosure 102 has another valve 106 that can be connected to the drain. Chemical source 108 is coupled to enclosure 102 via valve 110. Chemicals suitable for reacting with contaminants in the wash solution to generate a detectable signal such as a color are stored in a chemical source. Examples of these chemicals include, but are not limited to, chloride ion reagent (Hg (SCN) ₂ ), OPA, albumin reagent, biuret reagent, and microprotein-PR.

In use, the valve 104 is opened and the wash, cleaning or rinsing liquid in the chamber 20 is introduced into the enclosure 102 when the measurement is performed. The amount of wash liquor introduced into the enclosure 102 can be adjusted. Subsequently, valve 104 is closed and valve 110 is opened to introduce chemicals into enclosure 102. Once the chemical is introduced into the enclosure 102, the chamber 20 and the enclosure 102 must be completely separated from each other such that no chemical can be introduced into the chamber 20 at all. After the measurement is completed, the liquid in the enclosure 102 is drained through the valve 106. Enclosure 102 should have another clean wash liquid inlet (not shown) to introduce fresh wash liquid to clean enclosure 102. The amount of chemical added to enclosure 102 is controlled. Preferably, since the concentration of chemicals in the wash liquid in the enclosure 102 is about the same in different measurements, the intensity of the signal generated by the reaction between the chemical and the wash liquid may only reflect the content of contaminants in the wash liquid. Is not affected by the concentration itself.

A spectrophotometer 100 having a detector 112 and a light source 114 is provided to detect a signal generated by the chemical. Detector 112 and light source 114 may be placed inside or outside of enclosure 102. When they are located outside the enclosure 102 as shown in FIG. 14, at least a portion of the wall of the enclosure 102 allows the light source 114 to travel through the body of wash liquid within the enclosure and reach the detector 112. It must be transparent to the light from it. When the signal generated is in color, it can be observed with the naked eye, so the human eye can act as a detector.

The structure as already described in FIGS. 9-13 can be combined with the device 15 of FIG. 14. Optionally, chamber 20 may be connected to a vacuum pump or vacuum source 16. When the cleaning is complete, a vacuum may be applied to the chamber 20 to facilitate drying of the cleaned items 22 and 24. A sterilization system may be provided so that the chamber 20 can be used as a sterilization chamber. After cleaning, sterilization may be performed in the same chamber 20 without removing the instrument to be cleaned and sterilized. There is no restriction on the sterilization system to be used in the cleaning process of the present invention. Thus, any suitable sterilization system can be used in combination with the cleaning process. If necessary, cleaning and sterilization can be performed simultaneously by using a combined cleaning and sterilization solution, such as in combination with dissolved ozone or chlorine dioxide.

15A-15D illustrate various devices in accordance with other embodiments of the present invention. In these embodiments, a standard 120 covered with contaminants is provided. The purpose of standards covered with contaminants is to provide a standardized indication of the cleanliness of the items to be cleaned during the cleaning process. That is, the contaminated standard 120 may be cleaned simultaneously with the item or items to be cleaned and the cleanliness of the standard 120 covered with contaminants may be monitored. Correlation between the cleanliness of the item to be cleaned and the cleanliness of the standard 120 covered with contaminants for a particular device structure can be established through experiments. Thus, when a standard is cleaned to a certain degree, it will indicate that complete cleaning of the items to be cleaned has been achieved.

There are several advantages associated with the use of contaminated standards. For example, by using contaminated standards, anyone can focus on the detection of contaminants that have been removed from or remain on the standard during the standard and monitoring process for monitoring, and thus the monitoring method can be standardized. have. Contaminant levels and cleaning efficiency of the standard 120 may be controlled. Standard 120 may be exposed to the same or less efficient cleaning environment that the item to be cleaned is exposed, or standard 120 may be more contaminated than items 22 and 24 When the water is completely cleaned, the item to be cleaned is guaranteed to be fully cleaned. Another option is to contaminate the standard 120 no more severely than the items 22 and 24 (where the standard is covered with less contaminants). By placing the standard 120 in a very inefficient cleaning environment, the items to be cleaned will be completely cleaned before the standard is cleaned, this selection reduces the level of contaminants to which the detector is exposed, and thus, Eliminates potential problems associated with contaminating the detector surface with contaminants In general, conditions may indicate that standard 120 is to be cleaned to a certain level. , Items 22 and 24 can be set up so that they can be cleaned thoroughly.This allows the use of less sensitive detectors .. Standard 120 can be any suitable contaminant or combination thereof as already described. Preferably, the standard 120 may be covered with the same contaminants as those contained in the items 22 and 24 to be cleaned, however, if necessary, the standard 120 may be cleaned. It may be covered with contaminants that are different from those of items 22 and 24. This allows the use of specific contaminants to standards and the use of preferred types of detection techniques particularly suited to those types of contaminants Cleaning of Standards 120 Many other choices are valid as long as an appropriate correlation between the cleaning and the cleaning of the items to be cleaned is established through experimentation involving a particular device structure.

FIG. 15A illustrates a device 16 having a contamination detector 122 located within the enclosure 102 and a standard 120 covered with contaminants. Standard 120 may be any suitable surface covered with contaminants. For example, standard 120 may be a suitable piece of material or plate that is movably coupled to a support. Preferably, the connection between the standard 120 and the support 124 is made in such a way that the contact area of the standard is not contaminated. There are various ways to eliminate the cleaning efficiency of the standard 120 relative to that of the items 22 and 24. For example, the valve 104 can be adjusted to different levels to regulate fluid communication between the chamber 20 and the enclosure 102. Larger valve 104 may provide better fluid communication, so the cleaning efficiency in chamber 20 and enclosure 102 will be close to each other. Another option provides adjustable agitation systems in or both of enclosure 102 or chamber 20. By adjusting the agitation level, the cleaning efficiency in the enclosure 102 or chamber 20 can be adjusted to a predetermined level. The other part of the device 16 is similar to that of FIG. 14. In one embodiment, the valve 104 is opened at a predetermined level during the cleaning process, and the contaminant level of the cleaning liquid in the enclosure 102 is monitored by the detector 122.

In another embodiment, an apparatus similar to that shown in FIG. 14 is used, the only difference being that the standard 120 covered with contaminants is placed within enclosure 102. In this case, the standard 120 is made of a material that is transparent to the desired wavelength range. Preferably, standard 120 has a flat surface covered with contaminants that react with chemicals contained in chemical source 108 that produce a particular compound that absorbs light of a particular range of wavelengths (see FIG. 14). Light source 114 and spectrophotometer 112 may be used without a chemical source.

FIG. 15B shows another embodiment in which the standard 120 does not lie within the enclosure 102, but instead in a recess. As shown in this figure, the standard 120 is movably coupled to the support 122. Preferably, standard 120 is a flat plate having a contaminated surface on one or both sides. The support 122 is installed on the wall of the recess 130. Preferably, since the support 122 is movable and the standard can be coupled to the support 122 at various locations, the position of the standard 120 in the recess 130 can be adjusted. The recess 130 may have a different shape. For example, it may be an inclined gap with two sidewalls 132 diverging from the wall of the chamber 20 as shown in FIG. 15B. The two side walls 132 may be parallel to each other. If desired, the recess 130 may have an enclosed sidewall with only one end open to the chamber 20. Because of the limited space, the cleaning efficiency of the recess 130 is lower than the area in which the items 22 and 24 are placed, and the deeper and narrower the recess 130 is, the smaller the cleaning efficiency is. Thus, the relative cleaning efficiency of the standard 120 can be adjusted by placing it at different locations in the recess 130. Stirring levels in the chamber 20 may be used to adjust the cleaning efficiency.

The light source 114 and the detector 112 are provided on two opposite sides of the recess 130. Sidewall 132 is made of a material that is transparent to light from light source 114. Standard 120 is made of a material that is transparent to light from light source 114. Thus, quartz is a suitable material for both sidewalls 132 and standards 120. 15C and 15D illustrate two different structures of recess 130. In the arrangement shown in FIG. 15C, the recess 130 is located at the corner of the chamber 20. The light source 114 lies outside the chamber 20 in the space proximate the recess 130. In the arrangement shown in FIG. 15D, the recess 130 is also located at the corner of the chamber 20 but protrudes outward. The light source 114 and detector 112 lie outside the chamber 20 in a space proximate the recess 130. If the standard 120 to be used has a flat surface, this surface may be placed in any suitable direction, vertical, horizontal or angle. The light beam from the light source 114 can be vertical, horizontal or any other angle.

The apparatus illustrated in FIGS. 15A-15D can be readily adapted to further include a vacuum source for vacuum drying items after one or more other detectors, vacuum pumps or cleaning, sterilization systems of the appropriate type.

In general, embodiments of the device of the invention illustrated in FIGS. 9-15D may use one or more additional contaminant detectors. Contaminant detectors suitable for detecting proteins are particularly usefully added. In such embodiments, it is desirable to use one or more detectors for detecting inorganic contaminants in combination with ultraviolet-visible spectroscopic detectors suitable for detecting proteins and other organic species. An example of the latter type of detector is a spectrophotometer that uses a detection wavelength of 220 nm, and one of its principles has been found in the body in ultraviolet absorption wavelengths common to all proteins and many organic molecules. Many other wavelengths are also suitable, including 260, 265, 280 nm. Another preferred contaminant detector combination is to use one or more detectors with a chromatographic autotitrator to detect proteins. Another preferred detector combination is to use a turbidity detector as an ion-selective electrode detector. Combinations of detectors other than those described above may also be used. All of the apparatus illustrated in FIGS. 9-15D can use chamber 20 which also acts as a vacuum chamber, whereby vacuum drying can be performed in a chamber with a vacuum source. Various sterilization systems for liquid or gaseous sterilization can be combined in the apparatus of the invention illustrated in FIGS. 9-15D. When the narrow narrow lumen device is cleaned and / or sterilized, the chamber 20 is divided into two sub-chambers separated by a sealable interface having two open ends of lumens individually placed in the two sub-chambers. It can be further divided. As a pressure differential can occur between the two sub-chambers, the cleaning or sterilant liquid flows through the lumen. Thus, lumens can be cleaned and sterilized more efficiently.

The above embodiments are provided for illustrative purposes only and are not intended to limit the invention, and many variations are possible without departing from the spirit and scope of the invention.

1 is a graph showing sodium chloride release rate of sodium chloride inoculated stainless steel blades in deionized water at room temperature.

2 is a graph showing albumin and sodium chloride release rates of stainless steel blades inoculated with aluminum solution in deionized water at room temperature.

FIG. 3 is a graph showing sodium chloride and protein release rates of RPMI tissue culture medium + 10% fetal bovine serum (FBS) contaminated stainless steel blade in deionized water at room temperature.

4 is a graph showing sodium chloride and protein release rates of fetal bovine serum inoculated stainless steel blades in deionized water at room temperature.

FIG. 5 is a graph showing the sodium chloride and protein release rates of bovine whole blood inoculated stainless steel blades in 1% sodium dodecylsulfate solution at 23 ° C., 200 RPM agitation rate. .

FIG. 6 is a graph showing sodium chloride and protein release rates of bovine fully blood inoculated polytetrafluoroethylene strips in 1% sodium dodecyl sulfate solution at a stirring rate of 23 ° C., 200 RPM.

FIG. 7 is a graph showing the protein release rate of fully inoculated stainless steel blades of bovine in 1% sodium dodecyl sulfate solution at 21 ° C., 45 ° C. and different stirring rates.

FIG. 8 is a graph showing the protein release rate of whole blood inoculated polytetrafluoroethylene strips of bovine in deionized water at different temperatures.

9 is a schematic representation of one embodiment of the inventive device in which the method of the present invention may be practiced.

10 is a schematic representation of a second embodiment of the inventive device in which the method of the present invention may be practiced.

Fig. 11 is a schematic diagram showing a third embodiment of the device of the present invention in which the method of the present invention may be implemented.

12 is a schematic representation of a fourth embodiment of the inventive device in which the method of the present invention may be practiced.

Fig. 13 is a schematic diagram showing a fifth embodiment of the apparatus of the present invention in which the method of the present invention may be implemented.

14 is a schematic diagram of an apparatus according to another embodiment of the present invention having a chemical raw material that facilitates detection of contaminants.

15A-15D are schematic diagrams of an apparatus according to another embodiment of the present invention having standards covered with contaminants.

* Explanation of symbols for main parts of the drawings

20: cleaning chamber 22: medical device

24: surgical instruments 40, 44: liquid outlet

41, 47, 46, 57: valves 50, 55, 58: liquid conduits

56: liquid inlet 59: drain outlet

60: liquid pump 64, 70, 71: electrode probe

81: water reservoir 102: enclosure

104: valve 112, 122: detector

114: light source

Claims (8)

An apparatus for monitoring a cleaning process for a medical device, A chamber for receiving and cleaning the instrument with a cleaning liquid; 18. A standard comprising a predetermined amount of contaminants located within said chamber and in adjustable fluid communication with said chamber, said standard comprising: a standard in fluid communication with a liquid in said chamber; A detector that provides an indication of the amount of contaminants on the standard without removing the standard from the chamber; And And a sterilizer suitable for sterilizing the cleaned instrument in the device. The method of claim 1, wherein the indication is a signal selected from the group consisting of the concentration, potential, conductivity of the contaminant, transparency to a particular wavelength, or a color of the cleaning / rinsing liquid used for the cleaning. Equipment for cleaning process of medical instruments. The apparatus of claim 1, further comprising a light source that travels through the standard to produce a light beam of a predetermined wavelength reaching the detector. The apparatus of claim 2, wherein the standard is placed in an enclosure in adjustable fluid communication with the chamber. The apparatus of claim 4, wherein the detector comprises an electrode located within the enclosure. The method of claim 1, wherein the detector comprises ion-selective electrodes, conductivity, spectroscopy, ion chromatography, capillary electrophoresis, high performance liquid chromatography, liquid chromatography, radioactivity, gravity, infrared spectroscopy, partial pressure measurement and A cleaning process monitoring apparatus for a medical device, the apparatus selected from the group consisting of turbidity measurements. The apparatus of claim 1, further comprising a vacuum pump connected to the chamber, wherein the chamber also functions as a vacuum chamber. The apparatus of claim 1, further comprising a sterilization system.