Hygiene Flashcards
List preventative methods of disease
- Cleaning, disinfection and sterilisation
- Hygiene
- PPE
- Vaccination
- Isolation
- Barrier Nursing
What is a disinfectant?
A chemical that will inhibit or destroy pathogens, but not bacterial spores, on inanimate object such as floors and kennels
What is a antiseptic?
A chemical that will inhibit or destroy pathogens without destroying animal cells; used on living tissue, so is a skin disinfectant
What is a detergent?
A chemical that breaks down grease and dirt; does not kill microorganisms
What is sterilisation?
The removal of all microorganisms including bacterial spores
What does -cide mean?
Indicates a chemical that kills a particular microorganism
What does -stat mean?
The action of a chemical that prevents or inhibits the growth of a microorganism
Describe levels of decontamination
Level 1: Cleaning (Low-risk areas)
Level 2: Disinfection (Medium risk areas)
Level 3: Sterilisation (High-risk areas)
What are the 7 groups of disinefectants?
- Alcohols
- Aldehydes
- Biguanides
- Halogens
- Peroxides
- Phenols
- Quaternary ammonium compounds (QAC’s)
What are alcohols?
- Used for skin disinfection
- In practice: 70% solution of ethanol for skin preparation for surgery
Give 3 examples of alcohols
- Ethanol
- Surgical spirit
- Jeyes fluid, which is toxic to cats
What is an advantage of alcohol?
Rapid action
What are the disadvantages of of alcohols?
- Skin irritant
- Inactivated by organic matter
- Volatile
What are the 2 groups of aldehydes?
Formaldehydes and glutaraldehydes
What is an example of aldehyde?
Parvocide
What is an advantage of formaldehyde?
Not inactivated by organic matter
What are disadvantages of formaldehydes?
- Highly irritant and toxic
- Volatile
What is an advantage of glutaraldehyde?
Less irritant than formaldehydes
What is an disadvantage of glutaraldehyde?
Volatile
Give an example of biguanides?
Chlorhexidine; also known as hibiscrub
What are the advantages of biguanides?
- Low toxicity, so little skin irritation
- Can be actively enhanced by alcohols, QACs and alkaline pH
- Effective and fast acting
What are the disadvantages of biguanides?
- Effective on gram positive bacteria but not spores or viruses
- Daily use can reduce commensal bacteria
- Easily inactivated by organic matter
What are the 5 groups halogens are broken down into?
- Iodine
- Iodophor
- Chlorine
- Fluorine
- Bromine
Give 3 examples of halogens
- Povidone-iodine
- Halogenated tertiary amine like anistel
- Chlorine hypochlorite
What are the advantages of iodine and iodophors?
- Cheap
- Readily available
- Shorter activity time than chlorhexidine
What are the disadvantages of iodine and iodophors?
- Irritant to skin
- Stains surfaces brown
What are the advantages of chlorine hypochlorite?
- Cheap
- Readily available
What are the disadvantages of chlorine hypochlorite?
- Highly irritant to tissue
- Corrosive to metals
- Toxic
- Strong smell
- Can react with other compounds
What are the disadvantages of bromine and fluorine?
Too toxic for veterinary use
What are the 3 examples of peroxides?
- Hydrogen peroxide
- Proxygene compound
- Peracetic acid
What is an advantage of hydrogen peroxide?
Fast acting
What is an disadvantage of hydrogen peroxide?
Ineffective against organic matter
What is an advantage of proxygene compound?
Available as powder
What are the disadvantages of proxygene compound?
- Corrosive
- Variable results in presence of organic matter
What are the 4 groups phenols are broken down into?
- Black
- White
- Clear fluids
- Chlorinated
Give 2 examples of phenols
- Dettol
- Jeyes fluid
What are the advantages of phenols?
- Cheap
- Not easily deactivated by organic matter
What are the disadvantages of phenols?
- Toxic and irritant to skin
- Toxic to cats
- Strong smell
- Leaves residue
What are QACs?
Halogenated tertiary amines
What are the advantages of QACs?
- Low toxicity
- Good detergent properties
- Contact time 5 minutes
- not easily deactivated by organic matter
What are the disadvantages of QACs?
- Inactivated by hard water
- Expensive
What is nosocomial?
A hospital acquired infection
What are the 2 sterilisation methods
- Cold sterilsation
- heat sterilisation
What are the 3 types of cold sterilisation?
- Ethylene oxide gas
- Chemical solution
- Irradiation
What are the 2 types of heat sterilisation?
- Dry heat (Hot air oven)
- Steam under pressure (Autoclave)
What is ethylene oxide gas?
A gas that takes 12 hours to sterilise by inactivating DNA to stop cell reproduction of bacteria, fungi, viruses and spores
What are 3 hazards of ethylene oxide gas?
- Toxic
- Irritant to tissues
- Highly flammable
What is chemical solution?
- Chemical which equipment need to be submerged in for 24 hours to be sterilised
What is irradiation?
- When instruments/equipment is exposed to radiation
- E.g. prepacked needles, syringes, suture materials, surgical gloves and scalpel blades
What is dry heat (hot air oven)?
- A hot air oven which kills microorganisms, but needs 4-5 hours to kill spores
What is steam under pressure (autoclave)?
Steam temperature increases with pressure
How do you know if a chemical indicator has worked?
If a TST strip should change colour to show sterilisation
How are biological indicators used?
Using bacterial spores contained in a glass vial or withing a paper strip
