CRCST CRCST Microbiology and Infection Control 2 — Questions and Answers
Question 1: What does 'bioburden' mean in the context of instrument reprocessing?
- The weight of an instrument set
- The total number of microorganisms present on an item before sterilization (Correct answer)
- The chemical load in a sterilizer chamber
- The cost of reprocessing a tray
Correct answer: The total number of microorganisms present on an item before sterilization
Bioburden refers to the number of viable microorganisms contaminating an item prior to sterilization; lower bioburden improves sterilization efficacy.
Question 2: What type of precautions are used for ALL patients regardless of diagnosis in healthcare settings?
- Airborne precautions
- Contact precautions
- Standard precautions (Correct answer)
- Droplet precautions
Correct answer: Standard precautions
Standard precautions are applied to all patients and include hand hygiene, PPE use, and safe handling of sharps to prevent transmission of bloodborne and other pathogens.
Question 3: Which bloodborne pathogen is of the GREATEST concern for CS technicians handling contaminated sharps?
- Hepatitis A virus (HAV)
- Hepatitis B virus (HBV) (Correct answer)
- Rhinovirus
- Streptococcus pyogenes
Correct answer: Hepatitis B virus (HBV)
Hepatitis B virus is highly contagious via needlestick and sharps injuries and poses the greatest occupational bloodborne pathogen risk for CS technicians.
Question 4: What does 'high-level disinfection' (HLD) achieve that 'intermediate-level disinfection' does NOT?
- Removal of all chemical residue
- Destruction of all microorganisms except large numbers of bacterial spores (Correct answer)
- Sterilization of all items
- Cleaning of gross soil
Correct answer: Destruction of all microorganisms except large numbers of bacterial spores
High-level disinfection eliminates all microorganisms except high numbers of bacterial spores and is required for semi-critical items like flexible endoscopes.
Question 5: Why is thorough mechanical cleaning considered the most important step in the reprocessing cycle?
- It makes instruments look new
- It removes organic material that would shield microorganisms from disinfectants and sterilants (Correct answer)
- It prevents rusting
- It complies with billing requirements
Correct answer: It removes organic material that would shield microorganisms from disinfectants and sterilants
Organic debris such as blood and tissue can shield microorganisms from the lethal action of disinfectants and sterilants, making cleaning the critical first step.
Question 6: Which microorganism classification includes HIV, hepatitis B, and hepatitis C viruses?
- Prions
- Fungi
- Bloodborne pathogens (Correct answer)
- Gram-positive bacteria
Correct answer: Bloodborne pathogens
HIV, HBV, and HCV are bloodborne pathogens, microorganisms transmitted via contact with infected blood or body fluids that pose occupational risks for CS technicians.
CRCST CRCST Microbiology and Infection Control 2
What does 'bioburden' mean in the context of instrument reprocessing?