Sterilization and Disinfection

Ethylene Oxide Sterilization

-colorless, flammable, explosive gas -Sterilize heat and moisture sensitive items -Carcinogen and mutagen is extremely hazardous with inhaled, eyes or skin -exposure time 2-10 hours -temp 100-140 F -humidity 45-75% -gas concentration When EO mixes with water it forms ethylene glycol (BAD)

Which of the following statements about EO sterilization is true? 1. EO exposure is potentially carcinogenic and mutagenic 2. it cannot be used for heat sensitive items 3. it is effective against prions 4. items processed by EO sterilization may be used immediately

1

Based on what you have learned about prion disease, identify the facts that are true about prions. SATA 1.prions are not bacteria or viruses but rather malformed proteins 2. CJD is a degenerative neuralgic disease that appears to be caused by prions 3. prions appear to be resistant to most forms of sterilization used in health care settings 4. prions appear to have a marked vulnerability towards moist heat

1 2 3

Based on what you have learned about peracetic acid sterilization, identify the facts that are true regarding practice acid sterilization. SATA 1. it is a liquid chemical sterilization method 2. it uses low temps 3. it is equal in efficacy to steam and ethylene oxide sterilization 4. it requires the use of a special unit designed for this type of sterilization 5. it can be used for all surgical items

1 2 3 4

Shelf life is related to: SATA 1. exposure to external events 2. methods of sterilization 3. type of packaging material used 4. number of personnel who may have handled the package 5. time from initial sterilization

1 3 4

Packing systems should: SATA 1. permit sterilization to take place 2. maintain sterility for a limited period 3. be structured to provide for aseptic delivery of the contents onto the sterile field 4. be compatible with the sterilization process 5. be used according to the manufacturer's written instructions

1 3 4 5

Match each implant to the surgery type. 1. Teflon and Dacron patches 2. Stapedectomy prostheses 3. Synthetic mesh 4. Ventriculoatrial shunts 5. scleral buckles/bands A. ENT B. General C. Neuro D. Ophthalmic E. Cardiovascular

1 E 2 A 3 B 4 C 5 D

Match the following 1. ultrasonic cleaner 2. washer decontaminator/disinfector 3. washer/sterilizer A. process instruments through several cycles. instruments are not considered prepared for subsequent use B. allows handsfree processing. Renders instruments safe for handling C. removes fine debris through cavitation

1:C 2:B 3:A

Match the class of wound with the example. 1. Class I 2. Class 2 3. Class 3 4. Class 4 A. Gastrectomy B. Compound fracture C. Perforated viscera D. Hernia Surgery

1:D 2:A 3:B 4:C

Based on what you have learned about chemical indicators, match the indicator type with its description: 1. Class 1 2. Class 2 3. Class 3 4. Class 4 5. Class 5 6. Class 6 A. integrating>>reacts to all critical parameters over a specific range of sterilization cycles B. Emulating>>reacts of all of the critical parameters of a specific cycle C. Reacts to two or more of the critical parameters of sterilization D. Bowie-dick>>detects air leaks, ineffective air remove, and presence of non condensable gases; used in dynamic air removal sterilizers E. Demonstrates that the package has been exposed to the sterilization process to distinguish between processed and unprocessed packages F. Process indicator that reacts to a single parameter of the sterilization process

1:E 2:D 3:F 4:C 5:A 6:B

An integrator is a multiparameter indicator designed to measure which of the following parameters? 1. pressure, steam, and temp 2. temp, time, presence of time 3. pressure and sterility

2

Based on what you have learned about classification of wounds, identify the category in which acute appendicitis or cholecystitis is classified.

3

Low temp gas plasma hydrogen peroxide sterilization has which of the following properties? SATA 1. accommodates lumened instruments 2. exhaust monitoring is required 3. items can be stored for future use 4. no toxic residue 5. the sterilant is bactericidal, veridical, and fungicidal 6. useful for items that are heat sensitive

3 4 5 6

A packaging system for items undergoing sterilization should possess which of the following characteristics? 1. compatible with all sterilization processes 2. made of only disposable materials 3. Maintains sterility of the items for a specific length of time 4. Permits aseptic delivery of contents to the sterile field

4

The use of practice acid on surgical items requires the following consideration: 1. items can be stored for future use 2. items must be aerated 3. items must be isolated for 7 days 4. items must be immersible

4

Chemical Indicators

Class 1>>process indicator that demonstrates that the package has been sterilized Class 2>>detect air leaks, ineffective air removal, presence of non condensable gases Class 3>>reacts to a single parameter of the sterilization process Class 4>>reacts to two or more parameters Class 5>>reacts to all critical parameters Class 6>>reacts to all parameters of a specific cycle

Saturated steam sterlization

Fastest Heat sensitive items cannot be steam sterilized -Gravity Displacement>>gravity removes air -Dynamic air removal>>use vacuum pump to ensure that air is removed Parameters 1. steam saturation 2. pressure 3. temperature 4. time

Classification of Surgical Wounds

Purpose -facilitate tracking infections involving the surgical pt -learn how they occurred -prevention Categories -clean -clean contaminated -contaminated -dirty or infected

Monitoring and Measuring Process Controls

Recording charts and graphs>>permanent record of times and temps of the sterilization process Chemical indicators>>monitor, proper conditions were present Temperature specific indicators>>attainment of minimum temperature Integrator>>temp, time and presence of steam (based on the type of sterilant used) Daily function test>>Bowie Dick Test performed on high-vacuum/pre-vacuum sterilizers -place over drain to see if the air is removed

Surgical conscience demands the recognition of improper practices observed during surgery by:

any member of the health care team

disinfection

chemical or physical process of destroying all pathogenic microorganisms, except spores

In which surgical wound category should a total abdominal hysterectomy be classified?

clean contaminated

Class 1- Clean

clean operative wounds without infection and you do not enter the Respiratory, GU or GI tracts 1-5% risk of infection Examples--eye, hernia, breast, non traumatic

Disassembly, cool water rinse, enzymatic wash, and use of appropriate detergent are principles used in:

decontamination

Sterilization

destroying all microorganisms by exposure to physical and chemical agents

Biological Monitoring

document the efficacy of specific sterilization cycles, not the sterility of the item Contain known populations of microorganisms Geobacillus>>steam, hydrogen, ozone Bacillus>>EO,dry heat No growth, no color change, or no fluorescence demonstrates a negative response. Positive response>>cloudy, colonies, color change, fluoresncece

Immediate Use Steam Sterilization

for immediate use used only when there is insufficient time to process by the preferred method according to manufacturers instructions cleaned grossly lumens are brushed

Complete sterilization in EO is dependent on 4 primary variables: Poper time, humidity, temperature and

gas concentration

Disinfection

high level>>may not be effective on spores, or CJD intermediate>>does not kill spores low>>kills bacteria, viruses, and fungi

Immediate use steam sterilization can be used:

in urgent situations

After completion of the steam sterilization cycle, wrapped, sterilized items should be:

left untouched to cool for 30-60 minutes

Practice Acid Sterilization

liquid chemical uses low temperatures Advantages -rapid cycle time -low temp for heat sensitive instruments -environmental friendly products -absence of adverse health effects of the operators -compatibility with large variety of material and instruments Limitations -material incompatibility -unsuited for moister sensitive instruments -occasional noxious odor similar to vinegar -must fit within processing tray -use immediately

Class 3-Contaminated

open fresh traumatic wounds, break in sterile technique, spillage from GI, inflammation 15-17% risk of infection Laparotomy with spillage, gunshot wound, inflammation

Class 2-Clean Contaminated

operative wounds that you enter the respiratory, GI or GU tract under controlled conditions and without contaminating the surrounding tissue. No infection 8-11% risk of infection Example-D&C, TAH, gastrectomy, cholecystectomy, appendectomy elective, cystoscopy, TURP

Risk factors that contribute to surgical site infections

pre existing infection surgical technique>>catheter and drain length and type of surgery preexisting conditions>>obesity and diabetes impaired defense mechanisms>>immunosuppressed nutritional status>>malnutrition age>>premature, newborns, geriatric impaired skin integrity

Goals of Sterile Technique and Aseptic Practices

prevent surgical site infection optimize primary wound healing minimize the length of recovery from surgery

Storage of Sterile items

temp 72-78 4 air exchanges per hours 60-70% humidity limit traffic 8-10 inches above floor 18 inches below sprinkler heads

Class 4-Dirty

traumatic wounds with retained devitalized tissue or existing infection or perforated viscera or delayed closure of wounds infection was present before surgery 27%+ chance of infection incision and drainage, total evisceration, perforated viscera

decontamination

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

Spaulding Classification System

Items to be disinfected should be put into the following categories: Critical -instruments, contact with blood stream -implants -must be sterilized Semi critical -contact with mucous membranes (endoscopes, anesthesia equipment, and respiratory equipment -high level disinfection Noncritical -contact with unbroken skin (BP cuff, bedpan, pulse ox) -intermediate or low level disinfection

Match the following 1. disinfection 2. decontamination 3. sterilization 4. high level disinfection A. the use of physical or chemical means to remove, inactivate, or destroy blood borne or other pathogens on a surface or item B. the process of destroying all microorganisms on a substance by exposure to physical and chemical agents; the complete elimination of all forms of microorganisms C. a process that destroys all microorganisms with the exception of high numbers of bacterial spores D. a chemical or physical process of destroying all pathogenic microorganisms, except spores, on inanimate objects

1. D 2. A 3. B 4. C

Cleaning and decontamination

First>>Cleaning -remove gross soil -makes them safe for handling and assembly -most important step -mechanical or use a ultrasonic unit (remove fine debris through cavitation>>ultrasonic energy is passed through a water bath, creating bubbles that implode) Recommendations 1. make sure the facility can comply with the manufacturers written instructions for use 2. instruments should be kept free of gross soil during the surgical procedure (use sterile water) 3. Instruments should be cleaned and decontaminated ASAP Second>>Decontamination -remove soil, cooked on dirt is not sterile dirt -mechanical or washer decontaminator(load into chamber to be washed through several cycles) or washer sterilizer Types -enzymatic wash>>protein and fat, dried on stuff -appropriate detergent -cool water rinse>>gross debris -disassembly>>flush lumens, take apart pieces Recommendations 1.inspect instruments for cleanliness and working order 2. minimize the risk for transmission of prion diseases (CJD) Third>>Assembly -clean? function? corrosion? sharpness? loose? -all instruments joints and hinges must be opened to ensure contact with the sterilizing agent. All instruments with detachable parts must be left disassembled Fourth>>Packing -compatible with sterilization -aseptic delivery of contents Fifth>>Sterilization -all forms of microbial life are destroyed -saturated/immediate use steam, chemical, ethylene oxide, ozone