RA#1 Flashcards
What are common areas of the body to be colonized?
1) skin
2) mucous membrane
3) GI tract
What are some hospital acquired infections (HAI)?
1) surgical wounds
2) respiratory tract
3) urinary tract
4) bacteremia (primary and secondary)
5) gastroenteritis
6) hepatitis outbreaks
Which method of infection prevention is this?
total destruction or physical removal of ALL microorganisms including the more resistant forms like spores, mycobacteria, nonenveloped virsues and fungi
Sterilization
What are the 4 types of sterilization?
1) Moist heat
2) Dry heat
3) Ethylene oxide gas
4) irradiation
What’s an example of moist heat?
autoclave
What temperature and how long should an autoclave be operated to achieve sterilization?
121-132 degrees for >15 min
Which method of sterilization is the most dependable?
moist heat
How do moist heat get rid of microbes?
denaturing proteins, causing ssDNA breaks and compromise membrane integrity
Is boiling a sterilization technique?
NO, it’s a disinfection method!
What’s an example of dry heat sterilization?
oven
What are the recommended times and temperature to run oven for sterilization?
1 hour at 170 degrees
2 hours at 160 degrees
3 hours at 150 degrees
Does dry heat kill spores?
yes
How does dry heat kill microbes?
irreversibly denaturing proteins, causing ssDNA break and compromise membrane integrity
What is important about the use of eythlene oxide gas?
materials must be aerated for absorbed toxic or mutagen by-products
How does ethylene oxide gas work in killing microbes?
alkylating protein, DNA and RNA –> prevents normal cellular metabolism and replication
What are the two methods for irradiation?
1) UV
2) ionizing radiation (gamma rays)
Which method of sterilization is used for single-use plastic items such as syringes and catheters?
ionizing radiation
Which method of sterilization is used for hospital ORs and lab safety cabinets?
UV
Which method of sterilization is used for heat and moisture-sensitive devices?
ethylene oxide gas
Which method of infection prevention is this?
removing or killing most, but not all, viable microorganisms
disinfection
What kind of microbes can survive disinfection?
more resilient ones like mycobacteria, viruses, fungi and bacterial spores
Which level of disinfection can approach sterilization in effectiveness?
high-level disinfection
What is used in high-level disinfection?
1) glutaraldehyde
2) oxidizing agents: peracetic acid, hydrogen peroxide and chlorine compounds
Which type of equipment is high-level infection for?
all devices that cannot be sterilized: endoscopes and plastic surgical instruments used in invasiveprocedures that come into contact with tissues or blood
What kind of microbes can intermediate-level disinfection kill?
mycobacteria, bacteria, most viruses, most fungi, but not very effective against spores
What are examples of intermediate-level disinfection?
1) alcohols
2) iodine-containing compounds
3) phenolic compounds
What type of equipment is intermediate-level disinfection used for?
semi-critical instruments: laryngoscopes, endoscopes, vaginal specula, anesthesia breathing circuits, etc.
What kind of microbes can low-level disinfection kill?
most vegetative bacteria, some fungi and some viruses
What’s an example of low-level disinfection?
quaternary ammonium compounds
What type of equipment is low-level disinfection used for?
non-critical instruments such as stethoscopes, blood pressure cuffs, and EKG electrodes
What type of infection prevention method is this?
disinfectants used to lower the number of microorganisms on skin surfaces
antisepsis
What are examples of antisepsis?
1) alcohol
2) phenolic compounds
3) iodine-containing compounds
4) chlorhexidine
5) quaternary ammonium compounds
6) Triclosan
What is antisepsis effective against?
vegetative bacteria
Which of the antisepsis technique is the most effective on skin?
iodine-containing compounds
What are the two kinds of iodine-containing compounds?
1) tincture of iodine
2) iodophors
Which of the two kinds of iodine-containing compounds can irritate skin and should be removed with alcohol?
tincture of iodine (2% iodine and KI in EtOH)
How does iodophors work in killing microbes?
penetrate cell wall and cause disruption of proteins and nucleic acid structure and synthesis
Which antiseptic has broad antimicrobial activity but a slower rate of killing than alcohols?
chlorhexidine
How does chlorhexidine kill microbes?
membrane disruption but not spores
What is chlorhexidine generally used for?
skin cleansing, surgical scrub and pre-op skin prep
True or False. Chlorhexidine may be better at preventing bloodstream infections in patient with central line than iodine compounds.
True
What’s an example of quaternary ammonium compounds?
Benzalkonium chloride
How do quaternary ammonium compounds kill microbes?
attach energy-producing enzymes, denature cell proteins and disrupt cell membranes
Which organism are quaternary ammonium compounds not effective against?
Pseudomonas, viruses, spore and mycobacteria
What antiseptic compound is in hand soaps and some tooth paste products?
Triclosan
What organisms is Triclosan effective against?
bacteria including some mycobacteria. Do not work on spores
How does Triclosan work?
inhibit bacterial lipid synthesis and may disrupt cell membrane at higher concentrations
Which infection prevention method is this?
process of heating liquids to a specific temp for a period of time
Pasteurization
What does pasteurization kill?
viruses, bacteria, protozoa, molds and yeasts, but NOT spores
