Sterilization Flashcards
1
Q
Advantages of OPA over glutaraldehyde
A
- not an irritant to eyes/nasal passages
- no activation required
- no exposure monitoring
- 12 min HLD claim
2
Q
Factors affecting efficacy of disinfection and sterilization
A
- > # of microbes the more time a germicide needs
- prions and bacterial spores possess innate resistance to chemical germicides
- the more concentrated the disinfectant the greater efficacy and shorter time necessary
- temperature increase, increases disinfectant activity
- increase pH can increase/decrearse antimicrobial activity
- relative humidity effects gaseous disinfectants
- water hardness reduces rate of kill due to divalent cations
- organic material either protects bacteria or reacts with germicide
- biofilms are 1,000x more resistant to antimicrobials
3
Q
Alcohol disinfection
A
- optimum concentration is between 60-90%
- bactericidal not bacteriostatic
- not recommended for sterilizing medical/surgical equipment
- cannot penetrate protein rich material
- damage shellac mountings of lensed instruments
- swells/hardens rubber materials
- bleach rubber and plastic tiles
- flammable and require cool, well ventilated storage
- evaporate quickly
4
Q
Chlorine compound disinfection
A
- broad spectrum of antimicrobial activity
- do not leave toxic residues
- unaffected by water hardness
- inexpensive and fast acting
- removes dried or fixed organisms and biofilms
- corrosiveness to metals
- inactivated by organic material
- releases toxic gas when mixed with ammonia or acid
- decontaminates blood spills
- disinfects water distribution in hemodialysis centers/machines
- can be stored at room temp in opaque container but will lose 50% of chlorine levels
- when stored in closed brown bottle, not decomposition for 30 days
5
Q
Formaldehyde disinfection
A
- used both in liquid and gaseous states
- formaldehyde-alcohol is a chemical sterilant
- formaldehyde is a HLD
- healthcare uses are limited due to irritating fumes and pungent odor at low levels
6
Q
Glutaraldehyde disinfectant
A
- HLD and chemical sterilant
- needs to be activated
- short shelf life (14 days)
- 2.5% glutaraldehyde at 35*C reduces time to required to achieve HLD (5 min) but is limited to AER
- used most commonly as a HLD for medical equipment such as endoscopes, dialyzers, transducers, anesthesia and respiratory laparoscopic plastic trocars.
- noncorrosive to metals and does not damage lensed instruments, rubber or plastics
7
Q
Hydrogen Peroxide disinfectant
A
- under normal conditions is extremely stable when stored in dark containers
- ## 3% is stable and effective disinfectant when used on inanimate surfaces
8
Q
Iodophor disinfectant
A
- antiseptic and disinfectant
- best known and most widely used is povidone-iodine
- iodophors have been used for disinfecting blood culture bottles and medical equipment such as hydrotherapy tanks, thermometers and endoscopes
9
Q
OPA disinfectant
A
- exposure time is 12 minutes
- HLD label claims at 20*c vary worldwide
- In AERs with FDA cleared ability to maintain solution temps at 25*c, contact time is 5 minutes
10
Q
Peracetic Acid disinfectant
A
- lacks harmful decomposition products
- enhances removal of organic materias
- leaves no residue
- sporicidal at low temps
- corrodes coppor, brass, bronze, plain steel and galvanized iron
- there is an automated machine that uses to chemically sterilize medical, surgical, and dental instruments
11
Q
Peractic acid and Hydrogen peroxide disinfectant
A
- used for disinfecting hemodialyzers
12
Q
Phenolics
A
- absorbed by porous materials
- residual material can irritate tissue
- not FDA cleared as a high-level disinfectant for semi-critical items
- can be used to preclean or decontaminate critical and semi-critical devices
13
Q
Quats
A
- good cleaning agent
- high water hardness and materials such as cotton and gauze pads can effect microbicidal activity
- commonly used in ordinary environmental sanitation of noncritical surfaces and medical equipment that comes in contact with intact skin
14
Q
Pasteurization
A
not a sterilization process
purpose is destroy all pathogenic microorganisms except bacterial spores
time-temp relation for hot water pasteurization is generally 70*C for 30 minutes
15
Q
Steam Sterilization - general overview
A
- inexpensive, nontoxic, rapidly microbicidal, sporicidal, rapidly heats and penetrates fabrics
