Exam 4 - 28. Sterilization and Disinfection Flashcards
3
Death of a microorganism is the ______ of ability to reproduce.
4
Does micorbial death occur exponentially or all at once?
4
Probability of microbial killing is proportional to the _________ and to the ________.
6
What is sterilization?
6
What is disinfection?
6
What is antisepsis?
8
What are the hardest organisms to kill? What are the second hardest?
9
What does the suffix -cide mean?
9
What are microbistatic agents?
10
What are two differing factors in viruses that determine an organisms susceptbility?
10
What does mycobacteria have that protects it from some chemicals?
12
What are critical items? Do they need to be sterilized?
12
What are semicritical items? What kind of disinfectant is needed?
12
What are noncritical items? What kind of disinfectants are needed?
13
What does this describe?
– contaminated during patient care
– light handles, switches, x-ray equipment
– drawer handles, pens, telephones, doorknobs
13
What kind of disinfectant do you need for clinical contact items?
13
What kind of disinfectant is needed for clinical contact items?
13
What kind of surfaces are floors, walls, and sinks considered? What do you clean them with?
14
Are actively growing organisms or cultures more susceptible to killing than an older stagnant one?
14
What are two reasons why actively growing organisms are more susceptible to killing than older stagnant ones?
15
What are four properties of an organism’s environment that determine its susceptibility?
15
Is a thicker or thinner viscosity better for an agent’s action?
16
Amount of heat needed to kill ____ as moisture levels increase.
16
What temperature and pressure must autoclave material get to for 15 minutes?
17
What are three reasons why a dry heat oven is not as good as an autoclave?
18
What are the minimum temperature, time, and pressure requirements for sterilization?
19
UV light induced _____ in nucleic acids.
19
ionizing radiation such as X-rays and gamma rays causes ______ in nucleic acids and ____.
20
What does this describe?
– substitutes alkyl groups for H+ in nucleic acids and proteins
penetrates well – works on wrapped materials
– good for heat-sensitive plastics, equipment
– very toxic, can explode
– requires at least 4-6 h to work + hrs to detoxify
21
What chemical group does this describe?
– formaldehyde (formalin), glutaraldehyde
– cross-link DNA (stops replication), proteins
– low cost, no special equipment
– requires immersion for 6-10 h at room temp – carcinogenic, causes hypersensitivity
– now have formaldehyde gas sterilizers
22
What does this describe?
– uses vaporized hydrogen peroxide
– adds microwave- or radio-frequency energy
– produces free radicals that damage nucleic acids
g – no toxic byproducts
23
What are the two most common alcohol disinfectants?
23
What do alcohols do to proteins?
23
What concentration of alcohols are needed to disinfect?
23
What are three things that alcohols will not sterilize?
24
What chemical disinfectant does this describe?
– oxidizing agent - inactivates proteins
– damages enzymes
24
What percent H2O2 is needed to be a high level disinfectant?
24
Hydrogen peroxide loses potency during _____.
25
What does iodine precipitate?
25
What is iodine bound to?
26
What does this describe?
– disrupt lipid membranes
– may be mixed with soaps or detergents
– lysol, hexachlorophene, chlorhexidine
26
Phenols are toxic for the ____ unless ____ (use at ___%).
26
Phenols kill ____, ____, and many ____.
26
Do phenols kill bacterial spores?
27
What does this describe?
– inexpensive, but have to dilute fresh daily
– much more effective at acid pH
27
Does Chlorine kill HIV and Hepatitis?
27
Chlorine is recommended for ____ outbreaks.
28
What do detergents do?
28
Are detergents best used by themselves or in combination?
29
What does this describe?
-test efficacy of autoclaves
-used also in gas sterilizers
29
-change color to indicate effectiveness
-place inside packaged materials
30
What percent do alcohol based hand sanitizers need to be?
30
Are alcohol based hand sanitizers effective against norovirus and C. dif? What about covid?
