Sterilization and Disinfection

What are the primary variables dependent on complete Ethylene Oxide Sterilization?

1. Gas concentration based on model of sterilizer. 2. Proper exposure time - 2-10 Hours 3. Temperature - 38-60 degrees Celsius. 4. Chamber humidity of 45-75%.

Name the 2 Basic Types of steam sterilizers:

1. Gravity Displacement - Relies on gravity to remove air. Air and steam do not mix, and air is heavier than steam, so the more steam is introduced, the space in the chamber decreases and the air exits down the sterilizer's drain. 2. Dynamic Air Removal - Similar to gravity displacement, but are fitted with vacuum pump to ensure that air is removed from the chamber and the load before steam is injected. (Considered more efficient) There may also be a combination of the two.

Perioperative documentation of implants should include:

1. Placement and location of implants. 2. Name of the manufacturer 3. Lot and Serial Numbers 4. Type and Size of implant 5. Expiration dates 6. Any other information required by the FDA.

Name some types of sterilization techniques:

1. Saturated steam sterilization 2. Immediate use steam sterilization 3. Chemical sterilization 4. Ethylene Oxide Sterilization 5. Low-temperature hydrogen peroxide gas plasma sterilization 6. Low-temperature hydrogen peroxide vapor sterilization 7. Ozone Sterilization.

What are the 4 parameters required that affect the steam sterilization process?

1. Steam saturation - 2. Pressure - 3. Temperature - 121-135^C for Gravity Displacement, 132-135^C for Dynamic Air-Removal 4. Time - Temperature is maintained for a prescribed amount of time to achieve the elimination of microorganisms

What are the 3 AORN Guidelines for Cleaning and Care of Surgical Instruments?

1. Surgical instruments and powered equipment should be cleaned, handled, and used according to the manufacturer's instructions. 2. Instruments should be kept free of gross soil during surgical procedures. 3. Cleaning and decontamination should occur as soon as possible after instruments and equipment are used.

The Length of time an item is considered sterile depends on factors that include the following:

1. Type and configuration of packaging materials used. 2. Number of time a package is handled before use (external events) 3. Number of personnel who may have handled the package 4. Storage on open or closed shelves 5. Condition of the storage area (cleanliness, temperature, humidity, air exchange). 6. Use of sterility maintenance covers (dust covers) and method of sealing 7. Conditions during transport

Name some Automated Cleaning and Decontamination Devices:

1. Ultrasonic Cleaner - Removes fine debris through cavitation 2. Washer decontamination/disinfection - Allows hands-free processing and renders instruments safe for handling 3. Washer/sterilizer - Processes instruments through several cycles. Instruments are NOT considered prepared for use.

Define Disinfection

A chemical or physical process of destroying all pathogenic microorganisms, except spores, or inanimate objects. Submerging in a disinfecting solution.

Define High-Level Disinfection

A process that destroys all microorganisms (vegetative forms of bacteria, all fungi, all viruses) with the exception of high numbers of bacterial spores.

What is the FDA time definition for implants?

Any material that will remain in the body for longer than 1 year.

Explain the difference between a class 3 chemical indicator and a class 5 chemical indicator.

Class 3 Chemical Indicator refers to a single parameter of the sterilization process whereas a Class 5 Chemical indicator refers to all the parameters of a sterilization process.

Class IV - What is a dirty wound?

Dirty or infected wounds that include old traumatic wounds with: Retained devitalized tissue Wounds that involve existing clinical infection or perforated viscera and/or delayed primary closure of wounds. Infectious process was present before surgery. Examples include but are not limited to: Incision and drainage Total evisceration Perforated viscera

Define Aseptic Practices:

Patterns of behavior and processes that are implemented to prevent microbial contamination.

What are the risk factors which contribute to Surgical Site Infections?

Pre-existing infection Surgical Technique Length/Type of Surgery Pre-existing Conditions Impaired Defense Mechanisms Nutritional Status Age Impaired Skin Integrity

What are the goals of sterile technique and aseptic practices?

Prevent SSI Optimize primary wound healing Minimize the length of recovery from surgery

What is PCD?

Process challenge device. Should be used with routine process monitoring devices. These PCD's provide information to demonstrate that conditions for sterilization have been met.

What are the objectives of cleaning?

Remove visible soil (blood, tissue, bone) Remove invisible soil (microorganisms) Preparation of the surface of any item for sterilization/disinfection to allow direct contact with the sterilizing/disinfecting agent Protection and safety of patients and personnel

Compare and Contrast: Sterilization, Disinfection, Decontamination

Sterilization - destroying all microorganisms Disinfection: destroying all pathogenic microorganisms Decontamination: remove, inactivate, or destroy pathogens on a surface/item. Bioburden is decreased and contaminants are removed.

Class III - What is a Contaminated Wound?

Surgery that involves: Open, fresh, traumatic wounds Major breaks in sterile technique Gross spillage from the GI tract Incisions in which acute, nonpurulent inflammation is encountered Examples of contaminated wounds (include but not limited to): - Laparotomy with significant spillage - Traumatic wounds (GSW, Stab wounds, without perforation of viscera) - Acute inflammation of any organ without frank pus present (acute appendicitis or cholecystitis, compound fractures)

Define Sterile Field:

The area surrounding the site of the incision or perforation into tissue, or the site of introduction of an instrument into a body orifice that has been prepared for an invasive procedure. The area includes all working areas, furniture, and equipment covered with sterile drapes and drape accessories, and all personnel in sterile attire.

Define surgical conscience

The concept which allows no compromise in the principles of aseptic technique, since anything less can increase the potential risk of infection, resulting in harm to the patient.

Define Sterilization

The process of destroying all microorganisms on a substance by exposure to physical and chemical agents; the complete elimination of all forms of microorganisms.

Define Decontamination

The use of physical or chemical means to remove, inactivate, or destroy blood borne or other pathogens on a surface or item.

Define Sterile Technique:

The use of specific actions and activities to prevent contamination and maintain sterility of identified areas during operative or other invasive procedures.

After steam sterilization, how long should items not be moved or touched?

Wrapped, sterilized items should be left untouched to cool to room temperature for 30-60 minutes.

What is FIFO?

first in first out. Utilized with stock rotation of sterile items.

What is Peracetic Acid Sterilization?

Liquid Chemical Sterilization agent, use low temperatures. Equal efficacy to steam and ethylene oxid (EO) sterilization. Processing units are specifically designed for PA sterilization. Only certain surgical items can be processed through this. Environmentally safe. Rapid cycle type. Unsuited for moisture-sensitive instruments. Smells like vinegar. Limited on how many items can be processed at one time. Must be used immediately after sterilization.

When is immediate-use steam sterilization used?

ONLY when there is insufficient time to process by the preferred wrapped or container method.

Class II - What is a Clean-Contaminated Wound?

Operative Wounds in which: Respiratory, Alimentary, or genitourinary tract is entered under controlled conditions and without contamination of the surrounding tissue. No evidence of infection or no major break in aseptic technique. Examples include (but not limited to): - Dilation and currettage (D&C) - Total Abdominal Hysterectomy (TAH) - Gastrectomy - Cholecystectomy without spillage - Elective appendectomy - Cystoscopy (Cysto) - Transurethral Resection (TUR) bladder procedures on a patient with negative urine cultures.

What are the 6 Classes of Chemical Indicators?

1. Class 1 - Demonstrates the package has been exposed to the sterilization process to distinguish between processed and unprocessed packages. 2. Class 2 (Bowie-Dick): used to detect air leaks, ineffective air removal, and presence of noncondensable gasses (used in dynamic air-removal sterilizers) 3. Class 3 - Reacts to a single parameter of the sterilization process. 4. Class 4 - Reacts to 2+ critical parameters of sterilization 5. Class 5 (Integrating Indicator) - reacts to all critical parameters over a specified range of sterilization cycles. 6. Class 6 (Emulating Indicator) - Designed to react to all critical parameters of a specific cycle.

Name the Steps of Sterilization:

1. Cleaning 2. Decontamination 3. Assembly 4. Packaging 5. Sterilization 6. Storage 7. Transportation

Name the 4 principles of decontamination:

1. Enzymatic Wash - Enzyme detergent helps remove debris on items heavily soiled with protein/fat or if soil is dried on. (Pre-Clenz) 2. Appropriate detergent - Detergent compatible with materials in the device and suited for types of soil. 3. Cool Water Rinse: Removes gross debris, prevents possibility of bioburden and/or contaminants from baking onto the item 4. Disassembly: Instruments with lumens should be flushed with water/detergent solution. Open box locks and disassemble instruments with multiple parts. ALL items with detachable parts that can be separated need to be disassembled for cleaning/packaging/sterilizing.

Define Sterile:

Absence of all living microorganisms including spores

Define Aseptic:

Absence of all pathogenic microorganisms

What is Biological Monitoring?

After exposure to the sterilization cycle and incubation, the absence of growth indicates that appropriate parameters have been met. No growth, no color change, or no fluorescence demonstrates a negative response or that the intended physical conditions in the sterilizer were met.

What class chemical integrating indicator should be run with the load including a surgical implant (if IUSS of an implant is unavoidable?)

Class 5.

Class I - What is a Clean Wound?

Clean Wound = Clean Operative Wound No inflammation is encountered. The respiratory, alimentary, and genitourinary tracts are not entered. Examples include (but not limited to): Eye surgery, Hernia repairs, Breast surgery, Non-traumatic neurosurgery, Non-traumatic orthopedic, cardiac, or peripheral vascular surgeries.

What is Ethylene Oxide Sterilization?

Colorless, flammable, explosive gas. Used to sterilize heat and moisture sensitive environments. Hazardous and carcinogenic, mutagenic when inhaled. Stringent safety precautions should be used. Effective due to ability to penetrate packaging materials, device lumens, effective against virtually all microorganisms (including spores, mold, yeast, viruses). Limitations: items used by EO sterilization must be aerated for 12-16 hours prior to use to protect employees, it cannot be rinsed (creates antifreeze = ethylene glycol). Highly toxic (anaphylaxis can occur if contacts patient's blood). Can injure employees: Chemical burns, cataract formation, neurological damage, leukemia, spontaneous abortions.

What are the conditions that are important considerations in maintaining the sterility of an item?

Condition of storage area - Cleanliness - Temperature - 72 and 78^F - Air exchange: At least 4/hr - Relative Huminity - 60-70% Traffic should be limit access to those trained in handling sterile supplies. Should have adequate air circulation, ease of cleaning, and compliance to fire codes.

Provide an example of an item that falls into each of the Spaulding Classification categories and rationale for that classification:

Critical - Foreceps. Going directly into human cavity Semi-critical - Scopes. Will penetrate the body in a natural orifice which the mucous membranes will act as a barrier. Noncritical - BP cuff. Human skin will act as a protective barrier.

What are the 3 categories of the Spaulding Classification system?

Critical — instruments/objects introduced into the human body. These must be sterilized prior to use. If sterilization is not feasible, these items must receive high-level disinfection. (Any microorganisms present in these instruments poses a high risk of infection) Semi critical - should receive high-level disinfection, instruments that come in contact with mucous membranes and do not ordianarly penetrate the body surfaces (i.e. endoscopes through natural body orifices, anesthesia equipment). Items should receive high-level disinfection. (Intact Mucous membranes usually resists common bacterial spores) Noncritical - should receive intermediate or low level disinfection, items that come into contact with patient's unbroken skin (BP cuffs, bedpans, pulse oximeters). Should receive intermediate/low level disinfection. (Patient's skin acts as a protective barrier)

What is Low-Temperature Hydrogen Peroxide Gas Plasma Sterilization?

Hydrogen peroxide (liquid) is vaporized, which creates a plasma cloud and is utilized to sterilize. Gas plasmas are highly ionized, properties are bactericidal, virucidal, spork ideal, and fungicidal. Effective for moisture and heat sensitive items. Does not require aeration. Items are dry at the end of the cycle. Processing time is quick. The end product is oxygen and vaporized moisture. Nontoxic. Noncorrosive. Items can be stored for future use. Does not penetrate all lumen sizes. It requires a specific biological indicator used for low-temp plasma sterilization units.

Define IUSS:

Immediate use steam sterilization: In order to be used, must follow conditions: 1. Device manufacturer's written instructions are available and followed. 2. Items are disassembled and thoroughly cleaned with detergent and water to remove soil, blood, etc. 3. Lumens are bushed using a cleaning solution and flushed and rinsed thoroughly 4. Items are placed in a closed sterilization container that has been validated for IUSS. Items must be placed in a manner that allows steam to contact all instrument surfaces. 5. Measures are taken to prevent contamination during transfer to sterile field. 6. Items sterilized by IUSS are to be used immediately and not stored for later use.