Chapter 9 - Instrument Preparation, Antisepsis and Desinfection Flashcards by Sofs C R

Which microorganism can survive for over 90 days on pure polyester material?
A) Clostridium difficile
B) Staphylococci
C) Pseudomonas aeruginosa
D) Enterococci

B) Staphylococci

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What is a recommended laundry temperature for cleaning contaminated hospital textiles according to the US Centers for Disease Control and Prevention (CDC)?
A) 120°F (49°C)
B) 140°F (60°C)
C) 160°F (70°C)
D) 180°F (82°C)

C) 160°F (70°C)

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How are instruments classified for sterilization and disinfection purposes based on their risk for infection?
A) Nonsterile, semi-sterile, sterile
B) Low-risk, medium-risk, high-risk
C) Noncritical, semicritical, critical
D) Basic, intermediate, advanced

C) Noncritical, semicritical, critical

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What is the primary distinction between sterilization and disinfection?
A) Sterilization destroys all microbial life including spores
B) Disinfection eliminates spores but not vegetative bacteria
C) Sterilization is only for surgical tools
D) Disinfection can be applied to living tissue

A) Sterilization destroys all microbial life including spores

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Which sterilization method is commonly used in health care facilities?
A) Cold water immersion
B) Steam under pressure
C) Liquid soap disinfection
D) Ultraviolet light

B) Steam under pressure

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What is a key factor that affects the efficacy of disinfection and sterilization?
A) Type of medical device used
B) Temperature and pH of the process
C) Time of day the process is performed
D) Length of the surgery

B) Temperature and pH of the process

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What is the risk if the preparation and packing process is not regarded as clean?
A) Increased turnaround time
B) Recontamination with organic material
C) Loss of instrument functionality
D) Delay in surgical procedures

B) Recontamination with organic material

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What is the role of antiseptics in the disinfection process?
A) They are toxic to living tissues
B) They are used only on inanimate objects
C) They are nontoxic to living tissues
D) They eliminate bacterial spores

A) They are toxic to living tissues

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Which chemical method is NOT commonly used for sterilization in healthcare facilities?
A) Dry heat
B) Ethylene oxide (EtO) gas
C) Hydrogen peroxide gas plasma
D) Cold-water disinfection

D) Cold-water disinfection

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What is a critical factor to consider when applying disinfectants to inanimate objects?
A) Temperature of the room
B) Toxicity to living tissues
C) Color of the disinfectant
D) Contact time and concentration

D) Contact time and concentration

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What is the main difference between a disinfectant and an antiseptic?
A) Disinfectants are for living tissues, while antiseptics are for objects
B) Disinfectants are for inanimate objects, while antiseptics are for living tissues
C) Disinfectants kill all microorganisms, while antiseptics kill spores
D) Disinfectants are more effective than antiseptics

B) Disinfectants are for inanimate objects, while antiseptics are for living tissues

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What method of sterilization is typically used for instruments that cannot withstand high heat?
A) Cold sterilization
B) Steam sterilization
C) Dry heat sterilization
D) Ethylene oxide (EtO) gas sterilization

D) Ethylene oxide (EtO) gas sterilization

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How does water hardness affect the cleaning process?
A) Increases cleaning efficiency
B) Reduces effectiveness of blood removal in cold water prewashes
C) Has no effect on cleaning
D) Speeds up the sterilization process

B) Reduces effectiveness of blood removal in cold water prewashes

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What is a prerinsing alternative to manual cleaning for surgical instruments?
A) Alcohol-based rinses
B) Enzymatic detergent solution
C) Boiling in water
D) Chlorine rinse

B) Enzymatic detergent solution

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How long does a typical enzymatic detergent need for effective cleaning at room temperature?
A) 2-5 minutes
B) 10-20 minutes
C) 30-45 minutes
D) 1-2 hours

C) 30-45 minutes

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What type of detergent solution is recommended after prewashing instruments?
A) Acidic
B) Neutral or near-neutral pH
C) Alkaline
D) Chlorine-based

B) Neutral or near-neutral pH

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What should be used to clean instruments containing narrow lumens?
A) Metal brushes
B) Compressed air and soft, lint-free cloths
C) Steel wool
D) Household cleaning agents

B) Compressed air and soft, lint-free cloths

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After cleaning, how should surgical instruments ideally be dried?
A) Air-dried
B) Dried with compressed air
C) Towel dried
D) Left in direct sunlight

B) Dried with compressed air

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What cleaning method is most effective at removing impacted debris from complex surfaces?
A) Manual scrubbing
B) Boiling in water
C) Ultrasonic cleaning
D) Alcohol-based cleaning

C) Ultrasonic cleaning

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Which detergent is preferred during ultrasonic cleaning?
A) Foaming enzymatic detergent
B) Nonfoaming enzymatic detergent
C) Alcohol-based detergent
D) Neutral pH detergent

B) Nonfoaming enzymatic detergent

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Why must instruments be rinsed after ultrasonic cleaning?
A) To remove water
B) To cool them down
C) To remove loosened debris and cleaner residues
D) To sanitize them

C) To remove loosened debris and cleaner residues

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What is the function of an automated washer–disinfector in the cleaning process?
A) To sterilize instruments
B) To combine cleaning with heat disinfection
C) To lubricate instruments
D) To dry instruments

B) To combine cleaning with heat disinfection

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What temperature is achieved during the disinfection phase in an automated washer–disinfector?
A) 60-65°C
B) 70-75°C
C) 90-93°C
D) 100°C

C) 90-93°C

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What is the A0-value in the context of disinfection? A) A measure of time at 100°C B) A pH measurement C) A time-temperature equivalent used to measure disinfection effectiveness D) A measurement of mechanical cleaning efficiency

C) A time-temperature equivalent used to measure disinfection effectiveness

What is the recommended A0-value for highly secure disinfection? A) 1000 B) 2000 C) 5000 D) 10,000

C) 5000

What type of lubricant should be used on surgical instruments before sterilization? A) Oil-based lubricants B) Water-soluble lubricants C) Grease-based lubricants D) Alcohol-based lubricants

B) Water-soluble lubricants

How should hinged instruments be packed before sterilization? A) Closed B) Partially opened C) Fully opened D) Disassembled

C) Fully opened

What is the most effective wrapping material for sterilization? A) Cotton B) Linen fabrics C) Disposable nonwoven wrappers D) Paper

C) Disposable nonwoven wrappers

Why is cotton fabric not ideal for wrapping instruments for sterilization? A) It allows moisture to pass through B) It is too strong for autoclaving C) It damages the instruments D) It prevents proper sterilization

A) It allows moisture to pass through

What type of instrument packaging is not compatible with hydrogen peroxide gas plasma sterilization? A) Aluminum composite containers B) Paper pouches C) Cellulose-containing materials D) Synthetic nonwoven materials

C) Cellulose-containing materials

What should be done if a surgical pack becomes wet? A) Let it dry and store it B) Use it within 24 hours C) Reprocess it D) Store it separately from other packs

C) Reprocess it

Why is it important to maintain relative humidity and temperature during packing? A) To ensure packaging is easy B) To avoid the instruments rusting C) To prevent condensate buildup and contamination D) To achieve faster sterilization

C) To prevent condensate buildup and contamination

What is the shelf life of surgical packs in disposable nonwoven wrappers? A) 30 days B) 90 days C) 1 year D) Indefinite

C) 1 year

Why should packing materials be at room temperature before sterilization? A) To prevent condensation and ensure sterility B) To avoid damaging the instruments C) To ensure faster drying D) To increase sterilization effectiveness

A) To prevent condensation and ensure sterility

What is the advantage of using double packaging for surgical instruments? A) Increases sterilization speed B) Increases shelf life and extra security during surgery C) Reduces weight of the pack D) Avoids using disposable pouches

B) Increases shelf life and extra security during surgery

Which environmental factors increase the risk of contamination of surgical packs? A) Bioburden and traffic B) Lighting and storage temperature C) Noise levels and cleanliness D) Distance from the sterilization unit

A) Bioburden and traffic

When should sterility maintenance covers be applied? A) Before sterilization begins B) During the drying process C) After items are cool and dry D) Immediately after the sterilization process

C) After items are cool and dry

What contamination risk is common during the unpacking of surgical instruments? A) Airborne contamination B) Temperature fluctuations C) Improper handling D) Lack of sterilization indicators

C) Improper handling

Which type of contamination is most common in processed surgical instruments? A) Fungal B) Viral C) Protein residues and biofilm D) Prions

C) Protein residues and biofilm

Which instrument design increases the adherence of biofilm? A) Smooth surfaces B) Instruments with lumens and crevices C) Stainless steel tools D) Short and simple tools

B) Instruments with lumens and crevices

Which of the following is a key factor in reducing biofilm formation? A) Using chemical sterilizers B) Delaying the sterilization process C) Shortening the time between use and reprocessing D) Increasing water temperature

C) Shortening the time between use and reprocessing

ATP bioluminescence tests are used to detect: A) Heat sterilization effectiveness B) Residual contamination C) Humidity levels in storage rooms D) Proper mechanical indicator function

B) Residual contamination

Which sterilization indicator provides the highest level of sterility assurance? A) Chemical indicators B) Mechanical indicators C) Biological indicators D) Temperature gauges

C) Biological indicators

How should bowls be arranged in an autoclave to ensure proper sterilization? A) Placed flat on the surface B) Stacked on top of each other C) With openings facing down or to the side D) Filled with water

C) With openings facing down or to the side

Which type of bacteria spores are used to calibrate steam sterilization effectiveness? A) Coagulase-negative staphylococci B) Bacillus subtilis C) Geobacillus stearothermophilus D) Escherichia coli

C) Geobacillus stearothermophilus

Why should packs be loaded loosely in the autoclave? A) To prevent moisture buildup B) To allow for even steam circulation C) To reduce the number of packs sterilized at once D) To protect them from physical damage

B) To allow for even steam circulation

What is a critical feature of proper sterilization in valve containers? A) Sealing the container tightly B) Using chemical sterilants inside C) Ensuring the valve is open D) Adding extra cotton plugs inside

C) Ensuring the valve is open

What happens when steam contacts a cooler surface during sterilization? A) Evaporation B) Condensation C) Temperature equalization D) Air displacement

B) Condensation

What is the recommended drying time for low-density items like plastic or rubber after steam sterilization? A) 5 minutes B) 15 to 30 minutes C) 60 minutes D) No drying time is needed

B) 15 to 30 minutes

What is the purpose of the Bowie-Dick test? A) To check for leaks in autoclaves B) To confirm that air removal and steam penetration are complete C) To measure ATP levels in autoclaves D) To test mechanical indicator accuracy

B) To confirm that air removal and steam penetration are complete

Why is prion contamination a concern in ruminant surgeries? A) Prions are easily destroyed by steam sterilization B) Prions resist conventional sterilization methods C) Prions are not transmitted through surgical instruments D) Prions are only found in humans

B) Prions resist conventional sterilization methods

What sterilization process is used for items sensitive to heat or chemicals? A) Steam sterilization B) Filtration C) Radiation D) Ultrasonic cleaning

C) Radiation

Why should instruments be allowed to cool before applying sterility maintenance covers? A) To avoid plastic degradation B) To prevent condensation C) To enhance chemical indicator effectiveness D) To ensure quicker storage

B) To prevent condensation

Why is air displacement by steam critical in an autoclave? A) To prevent the formation of air pockets B) To ensure rapid cooling of instruments C) To create high-temperature dry heat D) To increase the pressure inside the autoclave

A) To prevent the formation of air pockets

Which type of filtration is commonly used for the preparation of small volumes of fluids in practice settings? A) Depth filtration B) Surface filtration C) Sieve filtration D) Ultraviolet filtration

A) Depth filtration

When loading items into an autoclave, how should single pouches be placed? A) Laid flat on the surface B) Stacked on top of each other C) Spaced properly in racks D) Placed inside another sterilized container

C) Spaced properly in racks

Why should valves in cannulas be left open during autoclaving? A) To prevent pressure buildup B) To allow proper steam penetration C) To avoid condensation D) To preserve valve function

B) To allow proper steam penetration

How should heavier or denser items be positioned inside the autoclave? A) Placed on the top shelves B) Placed on the bottom shelves C) Placed in the middle of the load D) Stacked in layers

B) Placed on the bottom shelves

What is the key factor in ensuring asepsis during steam sterilization? A) High air pressure B) Proper heat distribution C) Control of time, temperature, and pressure D) Use of chemical indicators inside the pack

C) Control of time, temperature, and pressure

Which factor contributes to the recontamination risk in improperly functioning autoclaves? A) Inadequate drying times B) Excessive exposure to heat C) Leakages in the autoclave system D) Overuse of sterilization chemicals

C) Leakages in the autoclave system

The SAL of a sterilization process is described by: A) Time to achieve complete sterilization B) The likelihood of contamination after sterilization C) Temperature and pressure readings in the autoclave D) The color change in the chemical indicator

B) The likelihood of contamination after sterilization

How do chemical indicators help during the sterilization process? A) By guaranteeing complete sterilization B) By providing evidence that packs have reached sterilization temperatures C) By detecting bioburden inside the pack D) By neutralizing any residual contamination

B) By providing evidence that packs have reached sterilization temperatures

Which microorganisms are typically used to test biological sterilization indicators? A) E. coli B) Prions C) Heat-resistant bacterial spores D) Biofilm-forming bacteria

C) Heat-resistant bacterial spores

What is the function of the mechanical indicators used in sterilization? A) To monitor bioburden on instruments B) To detect temperature and pressure fluctuations C) To control the drying process D) To track the type of sterilization cycle used

B) To detect temperature and pressure fluctuations

Flash sterilization is contraindicated for: A) Surgical tools made of plastic B) Instruments contaminated during surgery C) Implantable devices D) Non-porous instruments

C) Implantable devices

What is the primary purpose of low-temperature sterilization (LTS)? A) Sterilizing heat-tolerant instruments B) Sterilizing instruments that cannot withstand high temperatures C) Sterilizing large, simple instruments D) Sterilizing instruments without pre-cleaning

B) Sterilizing instruments that cannot withstand high temperatures

How does lumen diameter affect hydrogen peroxide gas plasma sterilization? A) Smaller diameter improves efficacy B) Smaller diameter decreases efficacy C) Diameter does not affect sterilization D) Larger diameter decreases efficacy

B) Smaller diameter decreases efficacy

thylene oxide (EtO) kills microorganisms by: A) Causing dehydration B) Inactivating proteins, DNA, and RNA C) Disrupting cell membranes D) Oxidizing enzymes

B) Inactivating proteins, DNA, and RNA

What is typically mixed with ethylene oxide to reduce flammability? A) CO2 or Freon B) Nitrogen C) Oxygen D) Helium

A) CO2 or Freon

What environmental concern is associated with Freon used with EtO? A) It is toxic to humans B) It contributes to ozone depletion C) It creates toxic by-products D) It is a greenhouse gas

B) It contributes to ozone depletion

What is the preferred diluent for EtO sterilization? A) Oxygen B) Freon C) CO2 D) Nitrogen

C) CO2

What stage is NOT part of the basic EtO sterilization cycle? A) Preconditioning B) Gas introduction C) Cooling D) Air washes

C) Cooling

What is the purpose of aeration after EtO sterilization? A) To kill remaining microorganisms B) To remove noxious EtO residues C) To dry sterilized materials D) To prevent corrosion

B) To remove noxious EtO residues

What effect does residual moisture in needles and tubing have on EtO sterilization? A) Enhances sterilization B) Prevents sterilization C) Reduces sterilization efficacy D) Has no effect

C) Reduces sterilization efficacy

What is the typical duration of mechanical aeration after EtO sterilization? A) 2-4 hours B) 8-12 hours C) 24 hours D) 48 hours

B) 8-12 hours

How long should EtO-sterilized implants be aerated in ambient room conditions? A) 2 days B) 7 days C) 10 days D) 2 weeks

D) 2 weeks

Which of the following instruments is unsuitable for gas plasma sterilization? A) Rigid endoscopy lenses B) Insulated electrosurgery instruments C) Flexible endoscopes D) Metal instruments

C) Flexible endoscopes

What phase is unnecessary in hydrogen peroxide gas plasma sterilization? A) Preconditioning B) Gas introduction C) Aeration D) Drying

C) Aeration

Why must items be fully dry before hydrogen peroxide gas plasma sterilization? A) Moisture can dilute hydrogen peroxide B) Moisture inhibits vacuum formation C) Moisture promotes microbial growth D) Moisture is unnecessary

B) Moisture inhibits vacuum formation

What is a potential drawback of using hydrogen peroxide gas plasma sterilization? A) It dulls surgical instruments B) It creates toxic residues C) It is unsuitable for very long narrow lumens D) It requires extended drying times

C) It is unsuitable for very long narrow lumens

Which disinfectant is most commonly used for high-level disinfection of endoscopes? A) Formaldehyde B) Glutaraldehyde C) Hydrogen peroxide D) Ethylene oxide

B) Glutaraldehyde

Which compound is used to neutralize glutaraldehyde before disposal? A) Sodium bisulfate B) Peracetic acid C) Hydrogen peroxide D) Ethylene oxide

A) Sodium bisulfate

Which pH range maximizes glutaraldehyde activity? A) 3-4 B) 5-6 C) 7.5-8.5 D) 9-10

C) 7.5-8.5

What is a common adverse effect of glutaraldehyde exposure for healthcare workers? A) Skin corrosion B) Cancer C) Respiratory irritation D) Memory loss

C) Respiratory irritation

Ortho-phthalaldehyde (OPA) has an advantage over glutaraldehyde because it: A) Requires no activation B) Has a longer shelf life C) Produces no fumes D) All of the above

D) All of the above

What is a potential risk when using ortho-phthalaldehyde? A) It may cause corrosion of metal instruments B) It can cause allergic reactions in urologic patients C) It forms toxic by-products D) It requires prolonged contact times

B) It can cause allergic reactions in urologic patients

Succindialdehyde has excellent compatibility with which type of instruments? A) Flexible endoscopes B) Metal implants C) Single-use plastics D) Wooden instruments

A) Flexible endoscopes

What limits the use of formaldehyde in healthcare settings? A) Its slow activity B) Its cost C) Its carcinogenic side effects and odor D) Its limited effectiveness

C) Its carcinogenic side effects and odor

Which chemical is safer for the environment and less toxic to staff than glutaraldehyde? A) Peracetic acid (PAA) B) Formaldehyde C) Ethylene oxide D) Ortho-phthalaldehyde

A) Peracetic acid (PAA)

Peracetic acid is typically used in which form? A) Gas B) Liquid C) Solid D) Powder

B) Liquid

Hydrogen peroxide sterilization primarily kills microorganisms by: A) Alkylation B) Protein denaturation C) Oxidizing cell components D) Free radical formation

C) Oxidizing cell components

The presence of which enzyme can protect bacteria against hydrogen peroxide sterilization? A) Protease B) Catalase C) Amylase D) Lipase

B) Catalase

What concentration of hydrogen peroxide is generally required for effective sterilization? A) 0.5-1% B) 1-3% C) 7.5-25% D) 30-50%

D) 30-50%

What happens if instruments are not properly dried before sterilization in a gas plasma system? A) They remain unsterilized B) They corrode C) They remain damp D) They become deformed

A) They remain unsterilized

What is the typical duration of a hydrogen peroxide gas plasma sterilization cycle? A) 30-75 minutes B) 2-4 hours C) 5-10 hours D) 24 hours

A) 30-75 minutes

For what reason might high levels of humidity affect the efficacy of LTS methods like hydrogen peroxide? A) Hydrogen peroxide decomposes in moisture B) High humidity prevents plasma formation C) High humidity causes instrument corrosion D) High humidity does not affect sterilization

A) Hydrogen peroxide decomposes in moisture

How does UV light contribute to sterilization processes? A) By dehydrating microbes B) By causing DNA damage in microorganisms C) By denaturing proteins D) By creating free radicals

B) By causing DNA damage in microorganisms

Which of the following characteristics is shared by both VHP and HPV systems? A) They both work by creating microcondensation B) They both reduce relative humidity C) They both prevent surface condensation D) They both use vaporized hydrogen peroxide

D) They both use vaporized hydrogen peroxide

Electrolyzed strong acid water (EAW) has a pH of less than ___. A) 7 B) 6 C) 5 D) 3

D) 3

The bactericidal effect of EAW is due to the formation of ____ during electrolysis. A) Hydroxy radicals B) Chlorine dioxide C) Sodium hypochlorite D) Hypochlorous acid

A) Hydroxy radicals

What happens to EAW's bactericidal effect in the presence of organic matter or biofilm? A) It is enhanced B) It remains the same C) It drastically decreases D) It becomes toxic

C) It drastically decreases

What property makes hypochlorites commonly used as disinfectants? A) They are slow-acting B) They have a broad spectrum of antimicrobial activity C) They leave toxic residues D) They are unaffected by organic matter

B) They have a broad spectrum of antimicrobial activity

Hypochlorous acid (HOCl) is primarily effective in which pH range? A) Low pH B) High pH C) Neutral pH D) Any pH

A) Low pH

Why is chlorine dioxide not suitable for use on flexible endoscopes? A) It discolors the casing B) It does not kill viruses C) It has no residual effect D) It is not broad-spectrum

A) It discolors the casing

What is the major component of Virkon peroxygenic acid? A) Potassium monoperoxysulfate B) Sodium hypochlorite C) Chlorine dioxide D) Peracetic acid

A) Potassium monoperoxysulfate

Why is Virkon considered unsuitable for disinfecting medical devices? A) It forms toxic by-products B) It does not kill endospores within a practical time C) It is expensive D) It evaporates too quickly

B) It does not kill endospores within a practical time

Alcohols are ineffective in the presence of which of the following? A) Organic debris B) Fungi C) Moist surfaces D) Detergents

A) Organic debris

What is the optimal concentration range of alcohol for its maximal antimicrobial effect? A) 30%-50% B) 50%-70% C) 60%-90% D) 90%-100%

C) 60%-90%

Which alcohol has the strongest bactericidal efficacy? A) Ethanol B) Isopropanol C) n-Propanol D) Methanol

C) n-Propanol 90-second 70% isopropyl alcohol scrub (IPA) winner

Ethanol is most effective against which type of pathogens? A) Bacterial spores B) Enveloped viruses C) Mycobacteria D) Yeasts

B) Enveloped viruses

Chlorhexidine gluconate is typically used in which concentration range for skin antisepsis? A) 0.5%-0.75% B) 1%-2% C) 2%-4% D) 5%-7%

C) 2%-4%

What is the primary mechanism of action of chlorhexidine (CHX) on bacteria? A) Disruption of bacterial protein synthesis B) Inhibition of DNA replication C) Damage to the cytoplasmic membrane D) Destruction of bacterial cell wall

C) Damage to the cytoplasmic membrane

CHX is reported to have limited effectiveness against which of the following? A) Gram-negative bacteria B) Gram-positive bacteria C) Methicillin-resistant S. aureus (MRSA) D) Mycobacteria

C) Methicillin-resistant S. aureus (MRSA)

CHX efficacy is reduced in the presence of which material? A) Chlorine dioxide B) Organic matter C) Hypochlorous acid D) Alcohols

B) Organic matter

In which type of solution is ethanol less effective for sterilization? A) 100% ethanol solution B) 60%-90% ethanol in water C) 70%-90% ethanol in saline D) 50%-60% ethanol solution

A) 100% ethanol solution

Which disinfectant can inactivate bacterial spores within a practical timeframe? A) Chlorhexidine B) Alcohols C) Peracetic acid D) Hypochlorous acid

C) Peracetic acid

What makes peracetic acid superior for sterilizing heat-sensitive instruments? A) It is non-corrosive B) It works at room temperature C) It leaves no toxic residues D) It enhances metal instruments

B) It works at room temperature

Alcohol-based hand rubs are typically most effective when containing: A) 40%-60% alcohol B) 60%-95% alcohol C) 95%-100% alcohol D) 100% alcohol

B) 60%-95% alcohol

Which disinfectant is reported to lose effectiveness in direct sunlight? A) Hypochlorous acid B) Isopropanol C) Chlorhexidine D) Peracetic acid

A) Hypochlorous acid

The primary mode of action of alcohols against bacteria is: A) Disruption of DNA B) Denaturation of proteins C) Oxidation of cell walls D) Chelation of metals

B) Denaturation of proteins

What is the primary mode of action of inorganic iodine? A) Disrupts DNA B) Alters the cytoplasmic membrane C) Penetrates the cell wall and disrupts protein and nucleic acids D) Inhibits RNA synthesis

C) Penetrates the cell wall and disrupts protein and nucleic acids

Why is resistance development against elemental iodine considered unlikely? A) It is highly concentrated B) It binds irreversibly to microbial proteins C) Its rapid action prevents adaptive resistance D) It accumulates inside bacterial cells

C) Its rapid action prevents adaptive resistance

Which of the following is NOT a disadvantage of using iodine in its elemental form? A) Tissue irritation B) Staining C) Rapid degradation in organic matter D) Radiopacity

C) Rapid degradation in organic matter

What is the primary function of the polyvinylpyrrolidone (PVP) carrier in iodophors like Betadine? A) Enhances staining of tissues B) Reduces iodine's corrosiveness C) Reduces iodine's antimicrobial spectrum D) Enhances tissue penetration

B) Reduces iodine's corrosiveness

What happens when a 10% PVP-I2 solution is diluted? A) Free iodine is neutralized B) More free iodine is released C) Iodine binds more strongly to PVP D) The bactericidal activity is reduced

B) More free iodine is released

What is the minimum contact time required for PVP-I2 to release free iodine? A) 30 seconds B) 2 minutes C) 5 minutes D) 15 minutes

B) 2 minutes

Which solution is considered more effective against spores? A) PVP-I2 in water B) PVP-I2 in alcohol C) Iodine tinctures D) Chlorhexidine in alcohol

A) PVP-I2 in water

What is a noted benefit of PVP-I2 as an ophthalmic solution? A) Higher bactericidal activity at 10% concentration B) Effective against fungal infections C) Cornea-friendly properties D) Superior spore-killing ability

C) Cornea-friendly properties

Why is PVP-I2 not recommended for lavage of the peritoneal cavity in horses? A) It induces metabolic acidosis B) It causes tissue necrosis C) It binds poorly to organic material D) It has no bactericidal effect in this area

A) It induces metabolic acidosis

Which antiseptic agent is effective against both MRSA and gram-negative bacteria in body washes? A) Chlorhexidine B) Octenidine C) PVP-I2 D) Benzalkonium chloride

B) Octenidine

What microbial population was least susceptible to octenidine in studies? A) Staphylococcus epidermidis B) Escherichia coli C) Candida albicans D) Pseudomonas aeruginosa

B) Escherichia coli

What distinguishes octenidine from CHX in terms of microbial action? A) Octenidine is less effective against gram-positive bacteria B) Octenidine does not harm human tissues C) CHX is more effective at low concentrations D) CHX acts faster

B) Octenidine does not harm human tissues

Quaternary ammonium compounds are ineffective against which of the following? A) Gram-negative bacteria B) Viruses C) Gram-positive bacteria D) Lipid-based microbes

B) Viruses

Which of the following antiseptics is used in contact lens solutions? A) Phenol B) Polyhexamethylene biguanide (PHMB) C) Quaternary ammonium compounds D) Octenidine

B) Polyhexamethylene biguanide (PHMB)

What is the primary advantage of PHMB over saline in wound care? A) Higher cytotoxicity B) Faster antimicrobial action C) Better tissue compatibility D) Reduced residual activity

C) Better tissue compatibility

What mechanism limits the combination of CHX and PVP-I2 in antiseptic solutions? A) CHX neutralizes iodine B) Both agents amplify each other’s toxicity C) They form an insoluble compound D) They have overlapping microbial targets

A) CHX neutralizes iodine

Why should diluted antiseptic solutions like iodine be discouraged for sinus lavages? A) They promote resistance development B) They cause tissue necrosis C) They are inactivated by organic material D) They do not kill fungi effectively

A) They promote resistance development

Which of the following microorganisms shows the greatest susceptibility to octenidine? A) Staphylococcus epidermidis B) Escherichia coli C) Pseudomonas aeruginosa D) Candida albicans

A) Staphylococcus epidermidis

Why is PVP-I2 considered cornea-friendly? A) It is less acidic than other iodine preparations B) It is less irritating at high concentrations C) It causes less staining on the cornea D) It releases iodine slowly to minimize toxicity

D) It releases iodine slowly to minimize toxicity

What class of chemicals does octenidine belong to? A) Bisphenols B) Biguanides C) Quaternary ammonium compounds D) Bispyridines

D) Bispyridines

What is the key reason that sequential use of CHX and PVP-I2 can be more effective than using either agent alone? A) It avoids neutralization of each agent B) They act on different microbial targets C) Synergistic effect against S. aureus D) Increased tissue penetration

C) Synergistic effect against S. aureus

Why is CHX resistance considered rare in gram-positive bacteria? A) Gram-positive bacteria lack efflux mechanisms B) CHX forms stronger bonds with gram-positive cell walls C) CHX’s concentration in hospitals is generally low D) Gram-positive bacteria have less envelope permeability

D) Gram-positive bacteria have less envelope permeability

Which of the following antiseptics has an anti-inflammatory effect in wound care? A) Octenidine B) PHMB C) PVP-I2 D) Benzalkonium chloride

B) PHMB

Which antiseptic has its bactericidal activity significantly enhanced by alcohol? A) PHMB B) CHX C) PVP-I2 D) Octenidine

B) CHX