Infection prevention control Flashcards
What is sterilisation?
Complete killing or removal of all types of micro-organisms
Bacteria
- Vegetative
- Spores - e.g. Clostridium tetani, C. difficile etc.
Viruses
Fungi
Mycobacteria
What are the common methods of sterilisation?
•Heat
–Moist, dry
•Chemical
–Gas, liquid
- Filtration
- Ionising radiation
–Used for single use disposable equipment
How does sterilisation by heat work?
•Moist heat
–Autoclave
- Delivery of steam under high pressure
- Specific pressure and temperature cycles
- Dry heat
–Oven
•Controlled temperature cycles
–160°C for 2 hrs or 170 °C for 1 hr
What is disinfection?
Removal or destruction of sufficient numbers of potentially harmful micro-organisms to make an item safe to use
What is antisepsis?
•“Antisepsis” is disinfection applied to damaged skin or living tissues
–Requires a disinfectant with minimal toxicity
How is disinfection achieved?
Almost always achieved by use of chemical disinfectants
Properties to consider:
–Effects on micro-organisms
•Antimicrobial spectrum, sporicidality
–Chemical properties
•Shelf life, in-use concentration, compatibility with other chemicals
–Physical effects
•Corrosiveness
–Harmful effects
•Irritant potential, toxicity
How do you decide which method of decontamination to use?
•Risk of infection
–High, intermediate, low
•Physical properties
–Item
–Packaging materials
•Decontamination level
–Sterilisation, disinfection (antisepsis), cleaning, disposal
- Heat is the least hazardous method and should be used where possible
- Chemical disinfection is largely limited to:
–Environmental decontamination (surfaces, spills etc.)
–Antisepsis
–Heat-sensitive items
What decontamination wound be performed for surgical instrument reprocessing?
•Risk of infection
–High
•Physical properties
–Metal construction
–Paper/cloth packaging
•Decontamination level
–Sterilization
•Decontamination method
–Moist heat
What decontamination would be performed on a flexible endoscope?
•Risk of infection
–High
•Physical properties
–Metal/plastic construction
–Fragile, sensitive parts
•Decontamination level
–“High level” disinfection
•Decontamination method
–Chemical
•Several alternative agents
Delivered via “washer-disinfector
What is performed on a syringe needle?
•Risk of infection
–High
•Physical properties
–Plastic/metal construction
–Paper packaging
•Decontamination level
–Sterilization
•Decontamination method
–γ-irradiation pre-use
–Disposal after use
What decontamination is performed on a central venous catheter?
•Physical properties
–Living tissue
•Decontamination level
–Disinfection (antisepsis)
•Decontamination method
–Chemical
•2% chlorhexidine in 70% isopropyl alcohol1
What decontamination is performed upon a surgeon’s hands?
•Physical properties
–Living tissue
•Decontamination level
–Washing
•Decontamination method
–Surgical scrub
