Infection Control, Sterilization, and Disinfection

Question 1

Most common types of Health Care Associated Infections

Answer 1

1. UTIs
2. Surgical site infections
3. Lower respiratory infections
4. Blood infections

Question 2

Factors that combine to cause HAIs

Answer 2

1. increasing number of drug-resistant pathogens
2. failure of healthcare personnel to follow infection control guidelines
3. increased number of immunocompromised patients
4. Overcrowding
5. Indiscriminate use of antimicrobial agents

Question 3

Nightingale

Answer 3

• Sanitation
• Breaking chain of transmission
• Linked fresh air to wellness

Question 4

Lister

Answer 4

• Development of antiseptic surgery

Question 5

Holmes

Answer 5

• Direct transmission of infection by healthcare personnel

- Mothers dying after childbirth because med students did not wash their hands

Question 6

Semmelweis

Answer 6

• Hand hygiene and transmission link

- washing hands after delivery = less chances of puerperal fever

Question 7

Negative pressure room

Answer 7

Protect CLINICIAN from patient (TB, chicken pox)

Question 8

Positive pressure room

Answer 8

Protect PATIENT from outside environment (burn victims, immunosuppressed)

Question 9

The different between sterilization and disinfection is….

Answer 9

Sterilization = complete destruction of all microbes
Disinfection = destruction of pathogens

Question 10

Antisepsis

Answer 10

Disinfection of LIVING tissue

Question 11

High level of disinfection kills…

Answer 11

Everything except some bacterial spores

Kills TB

Question 12

Intermediate level of disinfection kills…

Answer 12

Everything except fungi and all bacterial spores

Kills Hep B and C, HIV

Question 13

Low level/Hospital Level of disinfection kills…

Answer 13

Most bacteria, some fungi, some viruses

Question 14

Cleaning refers to…

Answer 14

Removal of visible soil

Question 15

Define lyophilization

Answer 15

process that combine drying and freezing

Question 16

Spaulding Classification

Answer 16

1. Critical - penetrates tissue, touches bone (disposed of or sterilized after)
2. Semi-critical - touches mucosa or non-intact skin (High level disinfection or sterilization)
3. Non-critical - touches intact skin (Low level desinfectant)

Question 17

Autoclave uses _____ at a pressure of ___ psi at ___C for ____ minutes

Answer 17

Moist heat
15 psi
121.5C
20 minutes

Question 18

Autoclaves destroys…

Answer 18

vegetative microorganisms
bacterial endospores
viruses

Question 19

Dry heat uses _____ to kill bacteria; process at ____C or ___ C for ___ or ____ hours respectively

Answer 19

Oxidation
180C or 160C
1 or 2 hours

Question 20

T/F: Dry heat usually not used on instruments, but may be used on biological waste

Answer 20

T

Question 21

T/F: Radiation can be used to sterilize plastics. Used by manufacturers to pre-sterilize items and also in facilities.

Answer 21

First statement is true, second is false

Only used by manufacturers for pre-sterilization

Question 22

What is the mixture of chemicals used in the chemiclave? At what temp and for how long?

Answer 22

• Alcohol, ketone, formaldehyde, and acetone

- 132C for 20-40 mins

Question 23

Disadvantages of the chemiclave

Answer 23

Damages plastics

Penetrates paper packaged articles, but not fabric wrapped

Question 24

Advantages of the chemiclave

Answer 24

Minimal rusting

Quick

Question 25

Chemicals used in sterilization

Answer 25

1. Ethylene Oxide (ETO) - "cold sterilization" 2. Hydrogen Peroxide 3. Hydrogen Peroxide Vapour 4. Paracetic Acid

Question 26

ETO

Answer 26

- Humidity and heat - 10-48 hours in solution to sterilize - Can be used on heat-sensitive materials - Very toxic

Question 27

Hydrogen Peroxide

Answer 27

- Produces destructive free radicals - Enhances removal of organic matter - Not compatible with metals

Question 28

Hydrogen peroxide vapour

Answer 28

- Byproducts are harmless | - 52 minutes to process

Question 29

Paracetic Acid

Answer 29

- 12 hours for complete sterilization - Causes corrosion - Very toxic

Question 30

Physical methods of disinfection

Answer 30

1. Pasteurization - moist heat at low temps (180C) - reduces infectious microorganisms in liquids - Does NOT kill spores 2. Boiling (100C) - can kill most micro life forms except bacterial spores and some viruses (Hep C)

Question 31

Name criteria for good disinfectant

Answer 31

1. Broad spectrum action 2. Retain potency 3. Harmless to tissue

Question 32

High level disinfectants (GOPH)

Answer 32

1. Gluteraldehyde - compatible with most materials - chronic exposures = health risks - shelf life only 14 days 2. Ortho phthalaldehyde (OPA) - fast - compatible with most materials - stains skin - slow sporadical activity 3. Parachutic acid (corrosive) 4. Hydrogen Peroxide

Question 33

Intermediate level disinfectants

Answer 33

1. Iodaphors - less irritation for tissue - no residual action 2. Phenols - initially used by Lister - can cause jaundice - not sporicidal

Question 34

Low level disinfectants

Answer 34

1. Quaternary Ammonium Compounds - May not be effective for Gram - bacteria - For patient care supplies or equipment

Question 35

What level of disinfectant is alcohol considered to be?

Answer 35

- Not considered a disinfectant | - Does not inactivate bacterial spores or hydrophilic viruses

Question 36

Dental water lines should be drained for _____ after each patient

Answer 36

15 secs

Question 37

It takes ____ for rubbing alcohol to disinfect hands

Answer 37

25 secs

Question 38

What level of disinfectant is used in clinic?

Answer 38

intermediate