Module10 4th Ed

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Sterile Processing University, LLC MODULE 10: DECONTAMINATION – PART II

Copyright Sterile Processing University, LLC – 2012 – All Rights Reserved. This material may not be copied or used without permission of SPU.

SELECTION OF DETERGENTS AND OTHER CLEANING AGENTS Detergents are cleaning agents that lower surface tension, dislodging soils and dissolving or suspending them in the solution so they can be removed by washing and rinsing. Detergents are synthetic (i.e., they are man-made from various chemicals into the desired product). These chemicals include agents to soften water (also called chelating agents), blood dissolvers, rust inhibitors, and the like.

Several factors must be considered in the selection of a detergent: the quality of the available water, the water temperature, the type and amount of soil on the item, the materials the item is made of, and the manner in which the item will be cleaned (manual or mechanical). No single cleaning agent can be used for the removal of all types of soils or is safe on all materials used to manufacture medical devices. As with most CS/SPD processes, the device manufacturer’s IFU take precedence in the selection of detergents and cleaning methods.

Detergents are available in powdered, solid, and liquid form. To ensure the efficiency of the detergent and to prevent residuals, it is imperative that the detergent be fully dissolved in the solution, which can sometimes be difficult to achieve with powdered or solid formulations. No matter which type of detergent is selected, the manufacturer’s recommendations on concentration must be followed. Using more than is recommended could, in fact, decrease the efficiency of the product and result in harmful residuals. In general, detergents used in the decontamination process should be low-sudsing (should not produce a large amount of suds) and free-rinsing (capable of being removed easily during the rinsing process) to prevent residuals being left on surfaces.

Many devices are available to facilitate the dispensing of accurate amounts of detergents. These devices include, but are not necessarily limited to, the following:

• A simple measuring cup

• A manual pump that is inserted into and attached to the detergent container and that dispenses a specified amount with each activation

• Automated centralized pumping stations that are connected directly to sinks or mechanical cleaning equipment

No matter which device is used for dispensing detergents, it is important that it be maintained appropriately. Measuring cups should be cleaned between uses. Manual pumps should be cleaned to prevent buildup of detergent at the dispensing spout; in addition, the amount of solution dispensed should be checked routinely to ensure that it has not changed. At least twice a year, automated pumps should be checked and maintained by an individual trained in the technology. Staff should receive in-service training when automated systems are installed, and they should be aware of signs of potential problems. It is also a good idea for the staff to mark the detergent level in the container at the beginning of each shift with the date and their initials. The incoming shift should see a drop in the detergent level (unless the washers were not in use). Although most mechanical washers have alarm systems, these can fail.

Only detergents recommended for use in healthcare facilities should be used. Detergents used in the home should not be used in healthcare facilities unless specifically recommended by the device

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manufacturer. Such products were not designed for the types of soils found in healthcare facilities, nor were they tested on the materials used in healthcare facilities.

Consideration must also be given to the water temperature and hardness. Unless otherwise directed by the detergent manufacturer, the temperature of the water during cleaning should be in the range of 109ºF to 140ºF (43ºC to 60ºC) and should never exceed 140ºF; otherwise, the cleaning process could actually be impeded. Many types of thermometers are available to measure the water temperature in the sink; some adhere to the side of the sink, and others (digital thermometers) have a probe that remains in the sink during processing. (See Figure 5-6 for an example.) The thermometer should be unbreakable and should be selected to meet the needs of the facility.

Figure 5-6 – Digital thermometer

TYPES OF DETERGENTS

Enzymatic (enzyme-based) detergents contain organic substances that assist in the breakdown of protein soils and blood. The concentration of the detergent and the temperature of the solution influence their effectiveness. Water temperatures of 109ºF to 140ºF (43ºC to 60ºC) are best for enzyme-based products. Higher temperatures can break down or destroy the enzymes, making them less efficient; temperatures below 109ºF (43ºC) can also have adverse effects, making enzymes sluggish and reducing their effectiveness. The enzyme detergent manufacturer’s specific instructions should be consulted to determine whether the enzyme is affected by water temperature and, if so, the appropriate temperature range. The water temperature should be monitored and documented.

Enzymatic detergents can be simple (containing a single enzyme) or complex (containing multiple types of enzymes). Examples of enzymes used individually or in combination in the formulation of enzymatic detergents include protease (a “proteolytic” enzyme), which breaks down blood, mucus, feces, and albumin; lipase (a “lipolytic” enzyme), which breaks down fat (e.g., bone marrow and adipose tissue); and amylase, which catalyzes starches and breaks down carbohydrates.

Organic acid detergents can be used to remove severe stains on stainless steel instruments. These detergents should not be used routinely because they can be corrosive. Care must be taken to be sure that the concentration and exposure times recommended by the manufacturer are closely adhered to. Routine or inappropriate use of these detergents will result in irreversible damage to the items being processed. The manufacturer of the device being processed should be consulted before an organic acid detergent is used.

High-alkaline detergents are used in some mechanical washers, followed by a neutralizing acid rinse to clean surgical instrumentation. It is important to recognize that this process, although safe and effective for stainless steel instruments, is not compatible with anodized aluminum rigid sterilization containers, rubber, some plastics, and other materials. The staff should be aware of which items can be processed

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in this manner and which cannot. The manufacturer of the device being cleaned should be consulted about this process. It is also important to understand that if anodized aluminum sterilization containers will be processed in a cart washer, the detergent will have to be changed to a neutral pH detergent because cart washers usually use high-alkaline detergents.

Non-abrasive cleaning agents are available for removing stubborn soils and stains; however, these specially formulated agents can be difficult to remove and must be thoroughly rinsed away. Medical devices that have been cleaned with these agents must be washed with a detergent afterwards.

Soaps are organic compounds (i.e., they are made from products found in nature). Many of our grandmothers made their own soap from lye and animal fat (both of which are organic in nature). By themselves, soaps are poor cleaners and can be difficult to rinse off. However, some device manufacturers recommend that their devices (e.g., mammary sizers) be cleaned with organic soap because of concern about patient sensitivity (the device material could absorb the chemical and cause a patient reaction). Although Ivory Snow is not 100% organic, it does not contain bleaches or other chemicals, reducing the chance of an allergic reaction. Some device manufacturers are now recommending that Ivory bar soap be used for cleaning because it does not contain any chemicals. However, soap products should be used only if specified by the device manufacturer because soaps are difficult to rinse off.

PRINCIPLES OF CLEANING

The manufacturer’s processing instructions for every device must be available and must be followed. However, certain general principles of cleaning apply to any item:

• Every surface of the item must come in contact with the cleaning solution.

• There must be some type of action that enhances the cleaning process, such as friction on the surfaces. Friction is created by scrubbing in manual cleaning, by the continuous spraying of cleaning solutions against the device surfaces in a mechanical washer, and by cavitation in an ultrasonic cleaner.

• All hinged items must be completely open during the cleaning process. The use of stringers is not recommended because the stringer might not be wide enough to permit good contact with the surfaces of the instrument, prolongs the decontamination process, and necessitates unstringing of the instruments for inspection of the instruments in the preparation and packaging area.

• Whenever recommended and indicated, multipart items must be disassembled for cleaning. After disassembly of any instrument, all parts should be kept together throughout the cleaning process to ensure that parts are not lost and that the instrument can be properly reassembled after cleaning is completed. Although some parts might appear to be interchangeable, they are not. Incorrect assembly can cause failure at the point of use and, possibly, patient injury.

• For large trays being prepared for processing in a mechanical washer, it might be necessary to disassemble the tray into more than one tray to ensure effective cleaning.

• To prevent damage to instruments when they are being sorted into trays for cleaning, delicate items should always be placed on top of heavier items.

• The mixing of different types of metal (e.g., stainless steel, copper, non-anodized aluminum, brass and chrome plating) should be avoided, because electrolysis (chemical changes in the composition of metals) can occur in any heated, moist environment (e.g., the wet, hot chamber of a mechanical washer or steam sterilizer).

• To ensure direct contact between the instruments and the detergent and water, all components such as silicone mats must be removed.

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• Rigid sterilization container systems and other containment devices for instrumentation must be cleaned before they are resterilized and reused.

The overall effectiveness of the cleaning process depends on appropriate water quantity and quality, the proper concentration (dilution) and type of detergent (or enzymatic agent), use of an acceptable method of cleaning (as recommended by the device manufacturer), proper rinsing and drying, correct preparation of items for an automated cleaning process (e.g., opening instruments, not covering them with bowls or small metal cups), the correct time and temperature in an automated cleaning process, adherence to the load capacity of the cleaning equipment (e.g., not overloading washers or ultrasonic cleaners), and correct performance of procedures and operation of equipment by personnel.

MANUAL CLEANING Manual cleaning might be the only effective method for certain instrumentation, such as devices with lumens, powered equipment that cannot be immersed, and items that are delicate or of complex design. Manual cleaning might also be performed as a preliminary step before mechanical washing to remove stubborn stains and soils. In some facilities, manual cleaning might be the only method available.

The sinks used for manual cleaning should be deep enough and large enough to contain items and minimize the potential for splashing. Adequate sink size is especially critical for gastrointestinal endoscopes, which can be as long as six feet, for bariatric instruments, and for many orthopedic instrument sets. The appropriate size and design of sinks are also important to the comfort and safety of the staff, who might work at sinks for long periods, and to their ability to easily retrieve items. AAMI recommends that sinks be 36 inches from the floor and 8 to 10 inches deep (ANSI/AAMI ST79). The width and length of the sink should be determined by measuring the largest tray that will be soaked in the sink and then adding approximately 4 inches to the width to permit lowering the set into the sink by hand. Three sinks should be used to accommodate each step of the process: presoaking/washing, preliminary rinsing, and final rinsing. Items should be disassembled—in the fully open position for cleaning—and, when applicable, totally immersed in the cleaning solution. To protect themselves from contaminants, CS/SPD personnel should always brush or clean devices with the device under the surface of the water. If low-foaming detergents are used, the device can be seen while being cleaned.

Detergents used for manual cleaning are meant to bind with soils and keep them suspended in the solution so they can be removed during the rinsing process. Products used for manual cleaning are concentrates that must be mixed with water to create a cleaning solution that, in general, is used for both presoaking and washing. These products are available in powdered, solid, and liquid form. Whichever form is used, it is very important to follow the manufacturer’s directions on how much to use and to ensure that the detergent is completely dissolved in the solution. Using more detergent than called for does not improve the cleaning action; in fact, it can impede the process by leaving residuals behind that do not rinse off and that will build up over time, causing instruments to bind or corrode. Therefore, as noted earlier, it is important to use measuring devices (e.g., a measuring cup, an automatic pumping station, or a hand pump that dispenses a predetermined amount of solution from the detergent container) to accurately measure the amount of detergent specified by the detergent manufacturer.

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Figure 5-7 – Manual cleaning below water level

To get the correct dilution, it is also necessary to know the volume of water being used. If a basin is being used for manual cleaning, how much water does it hold? How much water does the sink hold? It is recommended that a gallon jug be used to fill the basin or sink; the jug is filled with water and emptied into the basin or sink until the desired water level is reached (a sink is usually filled three-fourths full). A non-toxic marker is used to mark the water line. After the marks are made at various levels (e.g., 1 gallon, 2 gallons, 3 gallons, and so on, as determined by the facility), how much detergent is needed can be calculated. For example, if the basin water line is at 2 gallons and the detergent manufacturer recommends 1 ounce of detergent per gallon, then 2 ounces of detergent should be added for optimum results. NOTE: Many facilities have automatic detergent dispensers that facilitate the measurement of detergents. The pH of the cleaning solution should be between 7 and 9. Enzyme-based detergents are most often used for manual cleaning because of their neutral pH and their effectiveness in breaking down the soils found in the healthcare setting. Detergent solutions must be changed frequently to reduce the bioburden (contamination) and to prevent the recontamination of cleaned items and the environment. The old statement “change the detergent when the water is visibly soiled” is no longer valid. Microorganisms cannot be seen; therefore, frequent changing of the water is recommended.

Just as cleaning is the most important step in the decontamination process, rinsing is the most important step in the cleaning process because it removes loosened soils and debris. During manual cleaning, items are rinsed under running water. For either manual or mechanical cleaning, the final rinse should be performed with treated water to prevent mineral deposits. Whenever the detergent solution is changed, the sink or basin should be cleaned and disinfected (e.g., with 70% alcohol) before it is refilled. CLEANING IMPLEMENTS

During manual cleaning, soft-bristle brushes of various sizes and lengths and soft, lint-free cloths are used to create friction on device surfaces. Plastic or nylon brushes are recommended for general cleaning. Metal-bristle brushes are not generally recommended because they can damage the protective layer of surgical instruments. Such brushes can, however, be used on the tungsten carbide jaws of needle holders, which are difficult to clean because of the design. Recent innovations in metal brush manufacture have resulted in claims that such brushes can be used for general cleaning. When considering the type of brush to use, it is important for CS/SPD

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personnel to look to the manufacturer for documentation on the safety of a brush for use on general surgical instruments. Additionally, it is important to understand the limitations of the brush (e.g., some cannot be used to clean insulated, plated, or aluminum instruments). Brushes used to clean instruments with lumens should be large enough in diameter to achieve contact with the walls of the lumen but small enough that they do not have to be forced into the lumen. Each instrument should be cleaned individually. Brushes should not have porous handles (e.g., wood handles) because they can absorb liquids and harbor bacteria and cannot be adequately cleaned or disinfected. Before a reusable brush is used, its condition should be evaluated. Any brushes that appear worn or that have missing or bent bristles should be replaced. See Figure 5-8 for examples of acceptable and unacceptable brushes.

Figure 5-8 – Cleaning brushes

(The brushes at left and in the middle are unacceptable and should be discarded. The brush at right is acceptable.)

Abrasive pads such as steel wool and plastic “scrubbies” should not be used, because they will scratch device surfaces, providing places for bacteria and debris to collect and promoting corrosion. Sponges are not acceptable for use, because they harbor bacteria, cannot be easily cleaned or disinfected, and break apart during use, leaving small particles in the serrations of instruments. To prevent the formation of biofilms, all cleaning implements should be regularly cleaned and disinfected or sterilized (at minimum, at the end of each shift). Brushes can be run through washer–disinfectors or washed by hand and disinfected using alcohol. Brushes should be hung to dry. When they show signs of wear, they should be discarded. After an item is cleaned, it should be placed in a second sink for an initial rinse with tap water or treated water. The third sink should contain treated water for the final rinse to prevent spotting and to reduce the potential formation of pyrogens as the instruments dry.

MECHANICAL CLEANING

Ultrasonic cleaners, a type of automated cleaning equipment, transmit sound waves through a cleaning solution. Transducers located outside the walls of the unit’s cleaning basin emit sound waves that travel through the cleaning solution in the basin. As the sound waves travel through the solution, they create voids, similar to bubbles, that implode (burst inward) as they contact the instrument, drawing soil away from the surface (Figure 5-10). This mechanical action, called cavitation, is very effective in cleaning hard-to-reach areas such as box locks, serrations, ratchets, and the teeth on instruments.

The advantages of ultrasonic cleaning include its efficiency, consistency, and reliability. Because the cleaning ability of the ultrasonic process has been proven to be superior to other methods and can be

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consistently reproduced, it is more efficient than manual cleaning and, therefore, increases productivity and reliability.

According to CDC (2008), “bacterial contamination can be present in used ultrasonic cleaning solutions (and other used detergent solutions) because these solutions generally do not make antibacterial label claims. Users of ultrasonic cleaners should be aware that the cleaning fluid could result in endotoxin contamination of surgical instruments, which could cause severe inflammatory reactions.” Therefore, the ultrasonic water should be changed frequently.

Ultrasonic cleaners are available in a variety of styles: single-chamber units; multi-chamber units; and “sonic irrigators” capable of running the energized cleaning solution through lumens. In a multi-chamber system, the first chamber is usually for cleaning, the second for rinsing, and the third for drying.

Figure 5-9 – Ultrasonic cleaner

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Figure 5-10 – Cavitation

Ultrasonic lumen cleaners (Figure 5-11) are special ultrasonic machines specifically designed for lumened devices (e.g., laparoscopic instruments, flexible reamers). The units are small and fit on a countertop. Ultrasonic lumen cleaning, in combination with manual brushing, has been shown to be very effective. Water is manually added, as is the detergent. The unit has adapters of various sizes (usually small, medium, and large) to accommodate the jaws of laparoscopic instruments or lumened devices. The jaws or openings of lumened instruments are placed into the adapter, and the instrument is submerged into the solution. This process enables the energized solution to be forced continuously through the lumen. The adapters must be replaced from time to time, and inspection of the condition of the adapters is important. It is also important that the adapters are of the correct size for the instrument being processed and that they do not permit leaks at the points of attachment. After ultrasonic cleaning, the units use suction to remove entrapped debris from under insulation and from other hard-to-reach places. The manufacturer’s instructions for recommended detergents, amount of detergent to be used, and filling and cleaning the tank should always be followed. The equipment manufacturer’s instructions for replacement of filters should be followed; these filters filter out the debris removed from under the instrument’s insulation and elsewhere.

Figure 5-11 – Ultrasonic lumen cleaner

Vacuum area created by cavitation

Gas bubblesin water of ultrasonic cleaner Bubbles

implode

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Not all detergents are suitable for use in an ultrasonic cleaner. The detergents used in ultrasonic cleaners should produce a low to medium amount of suds or foam, should have a near neutral pH, and should contain surfactants to bind with the soils and hold them in suspension after they are removed from the instrument surfaces. Because cavitation creates sufficient cleaning activity on its own, the detergents used do not have to be complex; however, some enzymatic detergents are well suited for this purpose. Detergents used in ultrasonic cleaners improve the efficiency of the movement of the sound waves through the solution. The manufacturer of the detergent should be consulted to ensure that the product is suitable for use in an ultrasonic cleaner. Gross soil should be removed from instruments before they are placed in the ultrasonic cleaner. Things to remember when using an ultrasonic cleaner include the following:

• The device manufacturer’s instructions should be consulted to ensure that the device will not be damaged by ultrasonic cleaning. In particular, ultrasonic cleaning can damage plated instruments (by causing the plating to flake away) and endoscopic instruments (by dislodging the telescope lenses).

• The water in the ultrasonic cleaner should be changed frequently (as often as after every use or every two to three uses) to reduce the level of microorganisms. Although soil is visible, microorganisms are not; therefore, one cannot rely on seeing soil as a means of deciding when to change the water.

• Each time the ultrasonic cleaner is drained, it should be cleaned before it is put back into use. A fresh solution of detergent and water should be used for cleaning, and the equipment should be rinsed with copious amounts of water. The chamber should then be disinfected with a lint-free cloth soaked in 70% alcohol. To be effective, the alcohol should remain wet for 10 minutes.

• The process of cavitation has a tendency to create aerosols (particles of cleaning solution released into the air). To contain these aerosols and other contaminants, the ultrasonic cleaner should have a lid and the lid should remain closed during the cleaning process.

• The temperature of the water in the ultrasonic cleaner should be between 100ºF (38ºC) and 140ºF (60ºC). It is important to know the temperature in the ultrasonic cleaner to ensure that it does not interfere with the cleaning action of the detergent.

• The water–detergent solution in the ultrasonic cleaner must be degassed before it is used. (Tap water contains air, which can interfere with the ultrasonic process; degassing removes the air.) Degassing should be performed as directed by the manufacturer and with an empty basket inside the cleaner to avoid damaging the chamber walls. Some ultrasonic cleaners now have an automatic “degas” cycle.

• To ensure contact with all device surfaces, the instruments to be cleaned should be placed in a metal tray with a mesh or perforated bottom and perforated sides (to maximize exposure to the sound waves). The instruments should be evenly distributed in the tray to allow for maximum exposure. The use of plastic trays is not recommended because plastic tends to absorb the sound waves, which can interfere with proper cleaning. Trays should not be stacked; only one tray at a time should be placed in the chamber. Stacking trays can damage instruments and cause ineffective cleaning.

• Any hinged instruments should be in the fully open position. Baskets should not be overloaded. Instruments should not be placed higher than 3 inches inside the basket (Perkins, 1982).

• Unless the instruments will be subsequently processed in a mechanical washer with a rinse cycle, they must be thoroughly rinsed after ultrasonic cleaning to remove soils and residual detergent from device surfaces. (When the basket of instruments is lifted out of the chamber, soils can be redeposited on the instruments.)

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• After instruments have been processed in an ultrasonic cleaner, it is important to check them to ensure that any screws did not loosen because of the vibrations to which the instruments were subjected.

• The ultrasonic cleaner should be located in the decontamination area, because it provides a cleaning process.

MECHANICAL WASHERS

Detergents: Three types of detergents are used in mechanical washers; all are usually in the liquid form and are low suds/foam producers. The type of detergent used depends on what is being cleaned. For devices made of plastic or aluminum and for anodized aluminum containers, a detergent with a pH of 7 to 9 should be used. Relatively neutral detergents are less effective than more alkaline detergents in removing heavy organic soils. Moderately alkaline detergents (those having a pH between 9 and 11) are safe for stainless steel instruments but can be mildly corrosive to aluminum, copper, and brass. The third type of detergent is highly alkaline, having a pH higher than 11. These detergents are the most effective in removing heavy organic soils, but can accelerate the corrosion of surgical instruments and can leave scale deposits on equipment. To reduce the potential for corrosion, highly alkaline detergents are best used in a multistep process: first the alkaline wash, then a neutralizing acid rinse, then a regular rinse.

Most mechanical washers have automatic detergent dispensers; some have an alarm or light that indicates when the detergent level is getting low. It is essential that processing personnel verify the detergent level daily to ensure an adequate supply of detergent. For multi-process washers (e.g., tunnel washers), it must be verified that each product (e.g., enzyme, detergent, lubricant) has been hooked up to the correct tubing so that the detergent will be dispensed during the correct cycle. Another quality check is to remove and clean the drain basket daily. Debris (including instruments) often collects in the basket. For some washers, it is necessary to prime the detergent pump. It is important to consult the user manual for the washer to determine the quality checks that should be performed daily for that particular equipment.

Types of Mechanical Washers: Two types of mechanical washers are used in today’s healthcare setting: the washer–decontaminator (also called a washer–disinfector) and the washer–sterilizer. Since the late 1980s, when washer–decontaminators/disinfectors were introduced in the United States, washer–sterilizers have not been as widely used as they once were. In fact, these units are no longer manufactured. In washer–sterilizers, the wash and rinse cycles use spray arms located at the top, bottom and, sometimes, sides of the chamber. The final step in the cycle is the introduction of live steam into the chamber; the steam reaches a temperature of approximately 290ºF (143ºC) for an exposure time of approximately one minute. The cycle selection options are extremely limited, and only items that can withstand high temperatures can be processed in these units. Extensive manual precleaning is required to achieve satisfactory results from a washer–sterilizer.

The best results are achieved by processing instruments through a mechanical washer–decontaminator after ultrasonic cleaning. Ultrasonic cleaners do an excellent job cleaning instrumentation, but they do not disinfect the instrumentation at the end of the process. If instruments do not undergo a disinfection process after ultrasonic cleaning, personnel should wear gloves when handling the instruments during assembly and preparation for sterilization. The washer–decontaminator/disinfector had been used in Europe for many years before it was introduced in the United States. This equipment has been found to efficiently remove the soil and bioburden found on medical devices. Washer–decontaminators/disinfectors are available in a variety of configurations, depending upon the needs of the institution. Every unit provides cycles for precleaning, cleaning, rinsing, sanitization or disinfection, and drying. Some units, called tunnel washers or index washers, include ultrasonic cleaning in the process. It is important that all components of the washer be checked daily as recommended by the washer manufacturer. Some of the recommended performance checks include removing and cleaning the drain basket, verifying that the spray arms are moving, and

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verifying that the spray arm openings are not blocked. These checks are critical to ensuring effective cleaning.

These washers can have a variety of cycles, including a utensil cycle, an instrument cycle, a delicate cycle, and a heavy-soils cycle. It is essential for proper cleaning that CS/SPD technicians be thoroughly familiar with the available cycles and select the correct cycle. For example, if the utensil cycle is selected for orthopedic instruments, the cleaning will not be adequate.

Figure 5-12 – Washer–decontaminator

Some mechanical washers provide a level of decontamination with heat, so it is important to monitor the temperature in the washer–decontaminator daily (AAMI TIR34). The target temperature varies according to the type of washer; therefore, the washer manufacturer’s instructions should be consulted. Temperature checks are available from companies that offer cleaning effectiveness testing products. This testing should be documented.

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Figure 5-13 – Temperature check test for automated washers

Single-chamber washer–decontaminators/disinfectors have racks at several levels and spray arms under each rack, allowing greater productivity and efficiency than washer–sterilizers. Some include racks with special connectors to provide for the cleaning of tubing and lumened instruments. As with the ultrasonic irrigator, the connection between the instrument and the washer must be secure and must be appropriate for the instrument being processed. Most washer–decontaminators/disinfectors are quite versatile, providing multiple cycles with programmable cycle parameters and allowing use of various types of detergents, presoaking enzymes, special rinses with either tap water or treated water, and lubrication of instruments. Mechanical washer cycles usually include a prewash or soak cycle, a rinse cycle, a wash cycle, multiple rinses (including a final rinse with “pure” or treated water), and a sanitization or disinfection cycle. Other than the final sanitizing rinse at temperatures above 180ºF (82ºC), all cycles use water at temperatures below 140ºF (60ºC). Items processed by this method are safe for individuals with intact skin to handle while setting up trays and sets for sterilization. The multi-chamber tunnel or index washers began to appear in sterile processing departments in the early 1980s. These units are composed of three to five interconnected chambers, each with a specific task. The units are automatically loaded, and the instruments to be processed are carried in baskets through the phases of the cycle. As one basket moves to the next cycle, another basket is loaded and, at peak operation, it is possible for a clean basket to exit the washer every 3 to 5 minutes. The baskets typically enter the washer and undergo a prewash cycle, after which they pass through an ultrasonic cleaner. After ultrasonic cleaning, there are detergent wash, rinse, final rinse, lubrication, and drying cycles. The tunnel or index washer is designed to facilitate throughput and increase productivity; it is not designed to process complex or lumened instrumentation. Instruments can require significant precleaning. Regardless of the type of mechanical washer used, it is important for the sterile processing technician to select the correct cycle. Most of these machines have multiple cycles: gentle cycle, instrument cycle, orthopedic cycle (heavy soils), and utensil cycle are examples. All personnel should be familiar with the various cycles and follow departmental procedures for use of the correct cycle for the devices being washed.

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Figure 5-14 – Tunnel washer

NOTE: YOU HAVE COMPLETED MODULE 10 – DECONTAMINATION - PART II.

PROCEED TO MODULE 11 – DECONTAMINATION – PART III. Please click on the link below to go to Module 11. https://secure.netsolhost.com/spdceus.com/modules/fourth/tech/module11_pay.htm Good Luck!