2017 self-study #3 course...sterilization is the destruction of all forms of microbial life. the...

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2017 course #3 self - study course contact us: phone 614-292-6737 toll free 1-888-476-7678 fax 614-292-8752 e-mail [email protected] web dentistry.osu.edu/sms The Ohio State University College of Dentistry 305 W. 12th Avenue Columbus, OH 43210 The Ohio State University College of Dentistry is a recognized provider for ADA CERP credit. ADA CERP is a service of the American Dental Association to assist dental professionals in identifying quality providers of continuing dental education. ADA CERP does not approve or endorse individual courses or instructors, nor does it imply acceptance of credit hours by boards of dentistry. Concerns or complaints about a CE provider may be directed to the provider or to the Commission for Continuing Education Provider Recognition at www.ada.org/cerp. The Ohio State University College of Dentistry is approved by the Ohio State Dental Board as a permanent sponsor of continuing dental education. This continuing education activity has been planned and implemented in accordance with the standards of the ADA Continuing Education Recognition Program (ADA CERP) through joint efforts between The Ohio State University College of Dentistry Office of Continuing Dental Education and the Sterilization Monitoring Service (SMS). ABOUT this COURSE… READ the MATERIALS. Read and review the course materials. COMPLETE the TEST. Answer the 16 question test. A total of 12/16 questions must be answered correctly for credit. SUBMIT the ANSWER FORM ONLINE. You MUST submit your answers ONLINE at: http://dentistry.osu.edu/sms-continuing-education CHECK YOUR EMAIL for your CE certification of completion. TWO CREDIT HOURS are issued for successful completion of this self-study course for the OSDB 2016-2017 biennium totals. CERTIFICATE of COMPLETION is used to document your CE credit and is emailed to each course participant ALLOW 2 WEEKS for processing of your certificate. The Ohio State University College of Dentistry is an American Dental Association (ADA) Continuing Education Recognized Provider (CERP). ABOUT your FREE CE… FREQUENTLY asked QUESTIONS… Q: Who can earn FREE CE credits? A: EVERYONE - All dental professionals in your office may earn free CE credits. Each person must read the course materials and submit an online answer form independently. Q: Where can I find my SMS number? A: Your SMS number can be found in the upper right hand corner of your monthly reports, or, imprinted on the back of your test envelopes. The SMS number is the account number for your office only, and is the same for everyone in the office. Q: How often are these courses available? A: FOUR TIMES PER YEAR (8 CE credits).

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Page 1: 2017 self-study #3 course...Sterilization is the destruction of all forms of microbial life. The limiting requirement is the inactivation of bacterial spores. Proof of such destruction

2017course #3

self-studycourse

contact us:phone

614-292-6737

toll free1-888-476-7678

fax614-292-8752

[email protected]

webdentistry.osu.edu/sms

The Ohio State UniversityCollege of Dentistry305 W. 12th Avenue

Columbus, OH 43210

The Ohio State University College of Dentistry isa recognized provider for ADA CERP credit.ADA CERP is a service of the American DentalAssociation to assist dental professionals inidentifying quality providers of continuing dentaleducation. ADA CERP does not approve orendorse individual courses or instructors, nordoes it imply acceptance of credit hours byboards of dentistry. Concerns or complaintsabout a CE provider may be directed to theprovider or to the Commission for ContinuingEducation Provider Recognition atwww.ada.org/cerp.

The Ohio State University College of Dentistry isapproved by the Ohio State Dental Board as apermanent sponsor of continuing dentaleducation.This continuing education activity has beenplanned and implemented in accordance withthe standards of the ADA Continuing EducationRecognition Program (ADA CERP) through jointefforts between The Ohio State UniversityCollege of Dentistry Office of Continuing DentalEducation and the Sterilization MonitoringService (SMS).

ABOUT thisCOURSE…

READ the MATERIALS. Read and review the course materials.

COMPLETE the TEST. Answer the 16 question test. A total of 12/16 questions must be answered correctly for credit.

SUBMIT the ANSWER FORM ONLINE. You MUST submit your answers ONLINE at:

http://dentistry.osu.edu/sms-continuing-education

CHECK YOUR EMAIL for your CE certification of completion.

TWO CREDIT HOURS are issued for successful completion of this self-study course for the OSDB 2016-2017 biennium totals.

CERTIFICATE of COMPLETION is used to document your CE credit and is emailed to each course participant

ALLOW 2 WEEKS for processing of your certificate.

The Ohio State University College of Dentistry is an American Dental Association (ADA) Continuing Education Recognized Provider (CERP).

ABOUT yourFREE CE…

FREQUENTLY askedQUESTIONS…

Q: Who can earn FREE CE credits?

A: EVERYONE - All dental professionals in your office may earn free CE credits. Each person must read the course materials and submit an online answer form independently.

Q: Where can I find my SMS number?

A: Your SMS number can be found in the upper right hand corner of your monthly reports, or, imprinted on the back of your test envelopes. The SMS number is the account number for your office only, and is the same for everyone in the office.

Q: How often are these courses available?

A: FOUR TIMES PER YEAR (8 CE credits).

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2017 Course

#3

Written and Edited by:Sydney Fisher, BS

Release Date:September 15, 2017

8:30am EST

Last Day to Take Course Free of Charge:

October 15, 20174:30pm EST

Sterilization Monitoring Refresher

This is an OSDB Category B – Supervised self-instruction course

Most physical tasks that we perform produce immediate, visible results and feedback on how the task was performed. For example, when you clean a patient’s teeth – the patient’s clean teeth are immediately visible. Or when you write in a

patient’s chart – the written remarks are immediately visible.

Unfortunately, immediate feedback on your sterilizer’s performance is not possible. The direct proof of your sterilizer’s success is determined by

the presence or absence of microbes. The purpose of this self-study is to provide dental

professionals with adequate background information concerning the monitoring of

sterilization equipment.

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Sterilization Monitoring Refresher

Since microbes are invisible to the naked eye, there is no way toknow if such organisms are living on instruments that have beenprocessed in the sterilizer. Therefore, sterilizers must be monitored toassess their functionality. How can we do this? Through the use ofmechanical, chemical and biological indicators.

Spore formation is part of the bacterial life cycle, and is a way forbacteria to conserve energy and nutrients. Bacterial spores are resistantto extreme temperatures and other environmental exposures. Becauseof this, bacterial spores are considered a perfect challenge for yoursterilizers. If bacterial spores are killed during the sterilization cycle,more fragile organisms like Hepatitis B virus and HumanImmunodeficiency virus that may have survived on instruments afterscrubbing or soaking are also killed.

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Sterilization is the destruction of all forms of microbial life. The limiting requirement is the inactivation of bacterial spores. Proof of such destruction is the ultimate criterion for sterilization because spores are the most heat-resistant form of microbial life. Heat, pressure, and chemicals are usually involved in the sterilization process. Sterilization methods are more commonly used for food, medicine and surgical instruments.

Disinfection is the inhibition or killing of pathogens, which are disease-causing microbes. Spores are not killed during disinfection. Alcohols, bleach, and phenolic disinfectants are typically used to disinfect. Unlike sterilization, disinfection is usually used to decontaminate surfaces and air.

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Sterilization vs. Disinfection

What items must be sterilized?

Per the Centers for Disease Control and Prevention (CDC), medical devices that have contact with sterile body tissues or fluids are considered critical items. These items should be sterile because any microbial contamination could result in disease transmission. Critical items include forceps, scalpels, scalers, surgical burs, and medical implantation devices. These items must be sterilized properly using steam under pressure, dry heat, or chemical vapor.

Semi-critical instruments are considered instruments that do not penetrate soft tissues or bone, but may contact mucous membranes. Examples of semi-critical instruments include mirrors, reusable impression trays, and amalgam condensers. Ideally, semi-critical items should be sterilized after each use. However, if sterilization is not feasible, high-level disinfectant is appropriate. A high-level disinfectant is registered with the U.S. Environmental Protection Agency (EPA) as a “sterilant/disinfectant.”

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Non-critical items are those that only come in contact with intact skin.These instruments include external components of x-ray heads, bloodpressure cuffs, and pulse oximeters. These devices have a relatively lowrisk of infection transmission, therefore intermediate-level or low-leveldisinfection is appropriate. Intermediate-level and low-level disinfectantsare also registered with the U.S. EPA and will be labeled as such.

Processing Instruments Before Sterilization

Non-critical; semi-critical heat

sensitive instruments

Critical; semi-critical heat

resistant instruments

Mechanical cleaning of

instruments

High-level disinfectant/

sterilant

Store in dry, protected area

Mechanical cleaning of

instruments

Package instruments

Autoclave/dry heat/chemiclave; allow to dry if wet

Store unopened in dry, protected

area

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All critical and semi-critical dental instruments that are heat stable should be sterilized after each use. Before sterilization, or high-level disinfection, instruments should be cleaned to remove visible debris. Enzymatic and non-enzymatic cleaning solutions can be used for this. If possible, instruments should be soaked in water or disinfectant solution after use to prevent drying of debris. Instrument cassettes and/or mechanical cleaning (e.g., ultrasonic cleaners) may be used to reduce direct handling. Rust inhibitors may also be used to prevent corrosion of the instruments. Instruments that are rinsed and dried prior to sterilization are less susceptible to contamination.

Types of SterilizationAppropriate sterilization units should be FDA-approved.

Steam sterilization, or autoclaving, is the most widely used method of sterilization and is also the most dependable. The basic principle of steam sterilization is to directly expose items to steam, at the required temperature and pressure but a specified time. The main parameters that must be met for effective steam sterilization are temperature, pressure and time. Pressure serves as the means to obtain high temperatures for proper sterilization and microbicidal activity. The minimum exposure periods for these two temperatures are 30 minutes at 121oC (250oF) and 4 minutes at 132oC (270oF).

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Flash steam sterilization is another option, although not as popular. Flash sterilization is categorized by the very short sterilization time: 132oC for 3 minutes at 27-28 lbs. of pressure. Although flash sterilization is seemingly more convenient, there have been complications with the use of flash sterilized equipment.There are two basic types of steam sterilizers/autoclaves:

1. Gravity Displacement Autoclave1. Typically used for less porous loads

(glassware, bio-hazardous waste, vented containers, some unwrapped instruments)

2. High-Speed Prevacuum Sterilizer1. Better for porous loads (wrapped

instruments, surgical packs)

Dry Heat SterilizationDry heat sterilization should only be used for materials that might be damaged by moist heat, or materials that are impenetrable to moist heat. Examples of such materials are powders, petroleum products and sharp instruments that are susceptible to corrosion.

Advantages• Nontoxic• Dry heat cabinet is easy

to install• Low operating costs• Non-corrosive for metal

and sharp instruments

Disadvantages• Slow rate of heat

penetration• High temperatures are not

suitable for most materials

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The most common time-temperature relationships for dry heat sterilization are: 170°C (340°F) for 60 minutes, 160°C (320°F) for 120 minutes, and 150°C (300°F) for 150 minutes. Bacillus atrophaeus spores are used to monitor the sterilization process as they are more resistant to dry heat.

There are two types of dry-heat sterilizers: static-air and forced-air. Static-air sterilizers act like an oven, with heating coils that cause hot air to rise into the chamber. Static-air sterilizers are much slower to heat and less uniform in temperature control. Forced-air sterilizers, or mechanical convection sterilizers, use a motor-driven blower that circulates heated air throughout the chamber. These sterilizers are much quicker to heat than static-air sterilizers.

Chemiclave Sterilization

Chemiclaves use unsaturated chemical vapor for sterilization. The most common time/temperature relationship for chemiclave sterilizers is 20 minutes at 132oC (270oF). Glutaraldehyde is most commonly used as the chemical vapor in chemiclaves. Similar to autoclaves, chemiclaves use very high temperatures for sterilization, however, chemiclaves have a much lower risk of instrument corrosion. Chemiclaves can still be dangerous for heat-sensitive plastics and o-rings due to the high temperatures.

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Packaging Items for Sterilization

Items ready for sterilization should be wrapped or placed in rigid containers, and then arranged in trays. According to the Association for the Advancement of Medical Instrumentation (AAMI): Hinged items should be opened Items with removable parts should be diassasembled

(unless otherwise specified by the manufacturer) Devices with concave surfaces should be positioned to

facilitate drainage of water Heavy items should be positioned not to damage

delicate items

There are several choices for maintaining the sterility of instruments. The chosen packaging material must allow penetration of the sterilant (steam, heat, etc.), provide protection against contamination during handling after sterilization, and provide an effective barrier to microbial penetration. Examples of packaging materials include: Rigid containers Peel-open pouches (self-sealed or heat-sealed plastic

and paper pouches) Roll stock (paper-plastic combinations of tubing, cut

and sealed to form a pouch) Sterilization wraps (woven and non-woven)

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Loading Items into SterilizerItems should be arranged so that all surfaces will be directly exposed

to the sterilizing agent. Perforated trays should be placed parallel to the shelf and non-perforated containers should be placed on their edge. Small items should be loosely placed in wire baskets and peel packs should be placed on edge in perforated or mesh bottom racks. Peel packs and pouches can also be placed parallel to the shelf, provided that the paper side is on the bottom to allow for drainage of any condensation.

Some steam sterilizers have an automatic dry cycle, and some sterilizers indicate that sterilized items should be dried by opening the sterilizer door about half an inch for 30 to 60 minutes. Packages should already be dry at the end of chemical vapor and dry-heat sterilization cycles. Dry, cooled packages should be removed carefully from the sterilizer or sterilizer tray using gloves and not tongs. Tongs are more likely to damage the packaging. It’s helpful to have a written protocol for clinic staff to follow to avoid potential contamination after sterilization.

Storing Items After SterilizationStorage times for sterile packs are dependent on the porosity of the

wrapper and the condition of the storage space. Heat-sealed and plastic peel pouches have been reported to remain sterile for up to 9 months after sterilization. Many hospitals and clinics practice “event-related” shelf-life practice. This means that the items should remain sterile until some event causes them to become contaminated (e.g. a tear in packaging, packaging becomes wet, seal is broken). Contamination events can also include air movement, humidity, insects, flooding and temperature.

Sterile supplies should be stored at least 8 inches from the floor, 5 inches from the ceiling (18 inches from a sprinkler head), and 2 inches from walls to allow for adequate air circulation and fire codes.

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Monitoring Your Sterilizer

Sterilization procedures should be monitored routinely by using a combination of mechanical, chemical and biological indicators. Please see Page 16 for sterilization frequency by state. There are three types of indicators for proper sterilization: mechanical, chemical and biological.

Mechanical Indicators:Mechanical sterilization indicators include cycle time, temperature

and pressure. These parameters can be assessed by examining your sterilizer’s cycle printout or gauges.

Chemical Indicators:Chemical indicators are an inexpensive and easy way to monitor

your sterilizer and should be used in conjunction with biological indicators. According to the CDC, chemical indicators should not replace biological indicators because they indicate that your machine has reached two or more sterilization parameters (e.g. time, temperature, pressure), while biological indicators measure microbicidal power. Chemical indicators are attached to the outside of each pack to show that the package has been processed through a sterilization cycle. To ensure sterilization, chemical indicators should also be placed on the inside of each pack. Chemical indicators are grouped into six classes based on their ability to monitor one or multiple sterilization parameters. If the internal and/or external indicator suggests inadequate sterilization processing, the item(s) should not be used.

Class 5 Chemical Indicators

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Chemical Indicator Classifications

Class 1: Process

Indicators

These indicators react to one or more sterilization parameters. Intended for use with individual units (packs, containers) to indicate that the unit has been exposed to the sterilization process. Examples are indicator tapes, labels, and load cards.

Class 2: For use in

specific tests

Intended for use in specific sterilization test procedures. For example, Bowie-Dick type tests are specific for evaluation of air removal in pre-vacuum sterilizers.

Class 3: Single Variable

Indicators

React to one of the critical sterilization parameters. For example, a temperature tube contains a chemical pellet designed to melt at a specific temperature during the sterilization process.

Class 4: Multi-Variable

Indicators

Designed for pack control. These indicators are usually paper strips designed to react to two or more critical sterilization parameters.

Class 5: Integrating Indicators

The most accurate of the internal chemical indicators, and are used as an additional monitoring tool for pack control. Designed to react to all critical sterilization parameters. Require 3 separate time/temperature values to indicate proper sterilization.

Class 6: Emulating Indicators

Cycle-specific indicators. Emulating indicators also react to all sterilization parameters. Only require one time/temperature value to indicate sterilization. A separate inventory of Class 6 Indicators should be used for each sterilizer cycle setting.

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Biological indicators are recognized by the CDC and many other organizations to be the ideal monitor of the sterilization process because they use the most resistant form of microorganisms.

Biological Indicators

Bacillus atrophaeus spores (106) are used to monitor dry heat sterilizers and Geobacillus stearothermophilus spores (105) are used to monitor steam sterilization. B. atrophaeus spores should be incubated at 35-37oC and G. stearothermophilus spores should be incubated in tryptic soy broth at 55-60oC. Spore-strip biological indicators typically require up to 7 days of incubation to detect viable spores, however, there are current studies investigating the success of shorter incubation times.

Each biological monitoring strip should be accompanied by a control strip of the same lot number, which is not processed in the sterilizer, to determine the efficacy of a sterilizer. In a laboratory setting, the spore strip is aseptically removed from its protective glassine envelope and placed in a test tube of culture media for 7 days. Each day, the tube is inspected for cloudiness, which would indicate a failed spore test.

Bacillus spores are typically used in biological indicators because they are present in higher numbers than are the common microbial contaminants found on patient care equipment, which demonstrates that other potential pathogens in the load have been killed.

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What happens in the event of a failed spore test?

Sterilization failure can occur in about 1% of cycles, and the CDC has specified a procedure in the event of a failed spore test. A failed sterilization test can occur due to improper use of the sterilizer and slight variation in resistance of the spores. If the mechanical (e.g. time, temperature, pressure) and chemical (internal and/or external) indicators suggest that the sterilizer was functioning properly, a single failed spore test does not indicate sterilizer malfunction, but the spore test should be repeated as soon as possible. If the follow-up spore test is also positive, the sterilizer should be serviced before further use. Aside from implantable surgical items, items do not necessarily need to be recalled unless a sterilizer malfunction is found.

Failed (positive) spore test left; Normal (negative) spore test right.

As mentioned, cloudiness in the culture media indicates a failed spore test as viable microbes are present on the strip after sterilization. To confirm this result, and rule out contamination during laboratory processing, a Gram stain is prepared.

The microbes used on most biological indicators (B. atrophaeus

and G. stearothermophilus) are Gram-positive, spore-forming

organisms. A contaminated spore test would stain pink during the

Gram stain.

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Potential Causes for Failed Spore Tests

Cause Potential Result

Improper cleaning of instruments

Protein and salt debris may insulate organisms from direct contact with the sterilizing agent and interfere with its efficacy

Improper packaging Wrong packaging material for the method

of sterilization Excessive packaging material

Prevents penetration of the sterilizing agent; packaging material may melt.

Retards penetration of the sterilizing agent

Improper loading of sterilizer Overloading No separation between packages or

cassettes, even without overloading

Increases heat-up time and will retard penetration of the sterilizing agent to the center of the sterilizer load

May prevent or retard thorough contact of the sterilizing agent with all items in the chamber

Improper timing and temperature Incorrect operation of the sterilizer

Insufficient time at proper temperature to kill organisms

Recording sterilization information is important for ensuring patient safety. This information includes recording of sterilization dates/times, cycle parameters, and responsible personnel. If any issues arise, the designated person should document the problem and reprocess the items. Documentation should be made if an office is closed for 7 or more days to justify not running the required testing during that time period.

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Avoiding Sterilization Monitoring Errors

Educate the Staff Be sure that your entire office staff understands the importance of

regular testing, and your particular state’s sterilization guidelines.Assign One Person

Assign one dependable staff member to take responsibility for the regular testing. The dentist should periodically review the testing records with this staff person to ensure regular testing is taking place and that all testing documentation is in order.

Establish a Routine Plan to test each piece of sterilization equipment on the same day

of each week if possible.Establish a Calendar

Use a calendar to keep track of testing dates. Indicate on the calendar the date of testing, who performed the spore test and the mail date. It is also helpful to include a reminder to re-order spore strips.

Mail Tests Promptly Always mail tests on the same day the equipment was tested.

Maintain a Failure Log Keep a log of all test failure and document what remedial action

was taken.Review Reports

It is the responsibility of the dentist to review each monthly report as it arrives at the office. If there are any discrepancies, contact the monitoring service as soon as possible.

File & Retain Reports Keep all monthly sterilization reports in one accessible file. The CDC

recommends keeping sterilization records for 3 years, although each state may have more specific guidelines.

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STATE FREQUENCY STATE FREQUENCY

AL Weekly MT Recommended

AK Recommended NE Recommended

AZ Weekly NV Weekly

AR Monthly NH Weekly

CA Weekly NJ Weekly

CO Recommended NM Weekly

CT Weekly NY Recommended

DE Recommended NC Weekly

FL Monthly ND Recommended

GA Weekly OH Weekly

HI Weekly OK Weekly

ID Weekly OR Weekly

IL Recommended PA Weekly

IN Weekly RI Weekly

IA Weekly SC Weekly

KS Weekly SD Weekly

KY Weekly TN Weekly

LA Weekly TX Weekly

ME Weekly UT Recommended

MD Weekly VT Recommended

MA Weekly VA Recommended

MI Recommended WA Weekly

MN Weekly WV Weekly

MS Weekly WI Weekly

MO Weekly WY Recommended

Sterilization Frequency by State

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Sterilization Monitoring: A Case StudyA case study of a real-time evaluation of the risk of disease

transmission associated with a failure to follow recommended sterilization procedures.

Curtis J. Donskey, Marian Yowler, Yngve Falck-Ytter, Sirisha Kundrapu, Robert A. Salata, and William A. Rutala

BackgroundIt is critical to follow proper sterilization techniques in order to avoid

disease transmission in patient care situations. When sterilization failures do occur, medical professionals face uncertainty when determining disease transmission risks and subsequent infection control protocols. One major problem with routine sterilization and sterilization monitoring methods is that real-time assessments are usually not available.

In 2011, the Sterile Processing Department staff at an Ohio hospital identified two Steriset Sterilization Containers in which a steam chemical indicator strip indicated that sterilization was unsuccessful. After reviewing the sterilization procedures for that day, it was determined that the gravity cycle was selected for two autoclave runs instead of the pre-vacuum cycle that is recommended for Steriset containers by the manufacturer. Due to a lack in recordkeeping for indicator strips, it was calculated that up to 72 patients may have had operations performed with instruments that had been processed in the gravity cycle. It was uncertain whether any steam was able to reach the instruments during the gravity cycle due to the lack of data on how the Sterisetcontainers might function during that cycle. The purpose of this case study was to determine whether sterilization may be achieved with the Sterisetcontainers using the gravity cycle.

MethodsAll surgical instruments in the hospital are processed in the centralized

Sterile Processing Department. First, Sterile Processing staff uses a machine washer to clean and disinfect instruments. This machine uses a combination of enzymatic solutions, ultrasonic cleaning and a lubricant rinse to prepare instruments for the next step, steam sterilization. As mentioned, the SterisetContainer manufacturer recommends a pre-vacuum cycle.

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To start, the effectiveness of the machine washer was evaluated. Instruments used for this test were identical to those originally processed on the gravity cycle. To assess the removal of vegetative bacteria, the ends of the surgical instruments (e.g. retractors and clamps) that contact patient tissues were suspended for 1 minute in cultures of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE). To assess the removal of bacterial spores, instruments were place in a suspension of Clostridium difficile spores for 1 minute. The instruments were then placed into the machine washer, and control instruments were contaminated in an identical way but not processed through the machine washer. Test and control instruments were innoculated in nutrient broth and incubated to assess growth.

Sterilization was assessed both inside and outside the Sterisetcontainers. Cycle parameters were set to replicate those of the original gravity cycle runs: 270oF for 15 minutes at a pressure of 28 to 30 psig. The loading pattern of the autoclave for the test run was the same as for the incident. To asses sterilization outside of the Steriset container but inside the autoclave, a 3M Rapid Readout Steam Pack containing Geobacillus stearothermophilusspores was used in 4 of 5 trials. To assess sterilization inside the Sterisetcontainers, four methods were used: SteriGage Steam Chemical Integrator, 3M Steam Biological Indicator containing Geobacillus stearothermophilus spores, C. difficile spore suspension, and MRSA suspension.

ResultsThe machine washer consistently reduced levels of MRSA and VRE on

surgical instruments. C. difficile spores were detected on 5 of 15 (33%) of contaminated instruments that were processed through the machine washer, as compared to 15 of 15 (100%) control contaminated instruments (P = 0.0002).

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Overall, only 10% of the integrators inside the Steriset containers showed sterilization success, suggesting that steam penetration was insufficient. However, sterilization was achieved in 100% of the containers based on the G. stearothermophilus spore strips. Similarly, culture of C. difficile spores and MRSA were negative in all Steriset containers after autoclaving. Finally, the optimal temperatures measured by thermal probe placed in multiple locations inside and outside the Steriset containers during a gravity cycle were equivalent (270-274oF).

DiscussionDocumented transmission of pathogens due to failed sterilization practices is

relatively rare. Still, such failures lead to considerable uncertainty for hospital staff and infection control practitioners striving to ensure patient safety. In this case, there was uncertainty regarding sterilization in the event of failure to run the autoclave on the correct cycle. It has been demonstrated through this study that the risk associated with this failure to follow recommended sterilization practices was negligible.

The very low risk associated with this incident is mainly due to the very large margin of safety in modern sterilization processes. This study determined that the machine washer step prior to sterilization is extremely effective in eliminating most vegetative bacteria. Even in the absence of steam entry into the Steriset container, heat in the machine washer and high heat in the sterilizer was effective in killing vegetative bacteria and viruses. Sterilization based on killing of G. stearothermophilus spores and C. difficile spores was also consistently achieved inside the Steriset containers, despite the low number of successful chemical indicators.

Infection control programs should consider rapid evaluations when limited data regarding transmission risks associated with specific failures to follow recommended sterilization procedures are available.

Although the case study demonstrates that effective sterilization can be achieved when instruments are processed on a cycle that is not

recommended, it is important to have checks and balances in place to avoid contamination and disease transmission. The use of chemical

indicators allowed this Sterile Processing Department to quickly identify an issue, which allowed them to prepare a plan of action.

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Links to Resources

About the AuthorSydney Fisher, BS

Sydney Fisher graduated from Denison University in 2013 with a Bachelor of Science degree in Biology. After Denison, she joined a microbiology lab in the Institute for

Behavioral Medicine Research at OSU as a Research Assistant. She spent three years as a research assistant, splitting time between OSU Wexner Medical Center and Nationwide Children’s Hospital Research Institute, before joining the Sterilization

Monitoring Service in 2016, and she recently completed a Master of Public Health degree from the College of Public Health at OSU in August 2017.

Author can be reached at [email protected]

Neither I nor my immediate family have any financial interests that would create a conflict of interest or restrict my judgement with regard to the content of this course

Association for the Advancement of Medical Instrumentationwww.aami.org

American Dental Associationwww.ada.org

Centers for Disease Control & Preventionwww.cdc.gov

Ohio State Dental Boardwww.dental.ohio.gov

United States Air Force Dental Evaluation & Consultation Servicewww.airforcemedicine.af.mil/DECS

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References1. Claus, D. (1992). A standardized Gram staining procedure. World Journal

of Microbiology and Biotechnology, 8. Retrieved from https://link.springer.com/content/pdf/10.1007%2FBF01198764.pdf

2. Donskey, C. J., Yowler, M., Falck-Ytter, Y., Kundrapu, S., Salata, R. A., Rutala, W. A. (2013). A case study of a real-time evaluation of the risk of disease transmission associated with a failure to follow recommended sterilization procedures. Antimicrobial Resistance and Infection Control, 3(4). Retrieved from https://doi.org/10.1186/2047-2994-3-4

3. Hood E, Stout N, Catto B. Flash sterilization and neurosurgical site infections: Guilt by association. Am. J. Infect. Control 1997;25:156. 850.

4. Kanemitsu, K., Takayuki, I., Ishikawa, S., Kunishima, H., Harigae, H., Ueno, K., Takemura, H., Hirayama, Y., Kaku, M. (2005). A Comparative Study of Ethylene Oxide Gas, Hydrogen Peroxide Gas Plasma, and Low-Temperature Steam Formaldehyde Sterilization. Infection Control and Hospital Epidemiology, 26(5). Retrieved from http://www.jstor.org/stable/10.1086/502572

5. Kolstad, R. (1998). How well does the chemiclave sterilize handpieces? The Journal of the American Dental Association, 129(2). Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/9685763

6. Miller, C. Correct loading and unloading of a sterilizer vital for sterilization, sterility maintenance. The National Magazine for Dental Hygiene Professionals, 18(7). Retrieved from http://www.rdhmag.com/articles/print/volume-18/issue-7/columns/infection-control/correct-loading-and-unloading-of-a-sterilizer-vital-for-sterilization-sterility-maintenance.html

7. Rutala, W. A., Weber, D. J. (2008). Guideline for Disinfection and Sterilization in Healthcare Facilities. Healthcare Infection Control Practices Advisory Committee. Retreived from https://www.cdc.gov/infectioncontrol/pdf/guidelines/disinfection-guidelines.pdf

8. Rutala WA, Weber DJ, Chappell KJ. Patient injury from flash-sterilized instruments. Infect. Control Hosp. Epidemiol. 1999;20:458. 851.

Page 23: 2017 self-study #3 course...Sterilization is the destruction of all forms of microbial life. The limiting requirement is the inactivation of bacterial spores. Proof of such destruction

Post-Test Page 1Instructions

• Answer each question ONLINE (link provided on SMS website)• Answer 12 of 16 questions correctly to pass• Answer post-course survey questions and click “Finish”• Deadline is October 15, 2017 4:30pm

1. It is acceptable to use sterilized instruments even if the package has become wet.

a) Trueb) False

2. Paracetic acid is the most commonly used chemical in chemiclavesterilization.

a) Trueb) False

3. X-ray heads and blood pressure cuffs are examples of non-critical items.a) Trueb) False

4. Chemical indicators can be used in place of biological indicators.a) True b) False

5. Bacillus atrophaeus and Geobacillus stearothermophilus are Gram positive microbes.

a) Trueb) False

6. Mechanical cleaning is not required for non-critical items.a) Trueb) False

7. Class 6 chemical indicators are the most accurate.a) Trueb) False

8. Running instruments on the wrong cycle will lead to bacteria proliferation and disease transmission.

a) Trueb) False

DirectorJohn R. Kalmar, DMD, PhD

[email protected]

Program ManagerSydney Fisher, BS

[email protected]

Program AssistantNick Kotlar, BS

[email protected]

Page 24: 2017 self-study #3 course...Sterilization is the destruction of all forms of microbial life. The limiting requirement is the inactivation of bacterial spores. Proof of such destruction

Post-Test Page 2

9. It is possible for chemical indicators to fail when biological indicators are successful.

a) Trueb) False

10. The CDC recommends keeping sterilization records for 1 year.a) Trueb) False

11. Overloading your sterilizer increases the heat-up time.a) Trueb) False

12. Hepatitis B virus and Human Immunodeficiency virus are more fragile organisms than bacterial spores.

a) Trueb) False

13. Which of the following is not an example of a critical item?a) Scalpelsb) Pulse oximeterc) Implantation devicesd) Surgical burs

14. Which chemical indicator is cycle-specific?a) Class 1b) Class 3c) Class 4d) Class 6

15. Which is not true of sterilization (as opposed to disinfection)?a) Successful sterilization destroys all forms of microbial life.b) Sterilization practices are usually used for surfaces and

surrounding air.c) Heat, pressure, and chemicals are used in sterilization.d) Bacterial spores are the main measure of successful sterilization.

16. Which of the following tips to avoid sterilization errors is false?a) Educate staff members on sterilization practicesb) Maintain a sterilization failure logc) Always mail spore tests at the end of the weekd) Assign one dependable person to handle sterilization monitoring

tasks

End of Test

• Answer each question ONLINE (link provided on SMS website)• Answer 12 of 16 questions correctly to pass• Answer post-course survey questions and click “Finish”• Deadline is October 15, 2017 4:30pm

DirectorJohn R. Kalmar, DMD, PhD

[email protected]

Program ManagerSydney Fisher, BS

[email protected]

Program AssistantNick Kotlar, BS

[email protected]