Chapter 11 Sterilization

Question 1

MOA of iodine/iodophors

Answer 1

Oxidation/substitution by free iodine denatures proteins

Question 2

MOA of steam sterilization

Answer 2

Kills through coagulation and denaturation of proteins with moist heat

Question 3

MOA of ethylene oxide

Answer 3

Alkylation of proteins and nucleic acids obstructing cell metabolism and reproduction

Question 4

MOA of plasma sterilization

Answer 4

Use electromagnetic energy to create plasma phase from vapor of H2O2, oxygen, or peracetic acid mixture. Plasma has free radicals that deactivate cellular processes

Question 5

MOA of chlorhexidine

Answer 5

Disrupts the cell membrane

Question 6

Time and temp for steam sterilization

Answer 6

Typically 121 degrees Celsius for 30 minutes in a gravity displacement sterilizer (more common) with 15-30 minutes drying time
132 degrees celsius for 4 minutes in a prevacuum unit with 15-30 minutes drying time

Question 7

Prevacuum unit is used in which type of sterilization

Answer 7

Steam

Question 8

Benefits of steam sterilization

Answer 8

Allows for lower temps to be used
efficacious against spores

Question 9

What is true in regards to bowls in steam sterilizers

Answer 9

Bowls will trap cool air if open facing up and will not sterilize appropriately

Question 10

What material should not be used in ethylene oxide sterilization

Answer 10

Glass - it resists penetration

Question 11

Which sterilization method and material combination will cause toxicity if not aerated?

Answer 11

Ethylene oxide is absorbed by rubbers and plastics. Aeration is needed.

Question 12

Benefits of plasma sterilization

Answer 12

Lack of toxic residues - Since using H2O2 does not require aeration
useful for moisture and heat sensitive items
Short cycle time

Question 13

Which materials should not be used in plasma sterilization

Answer 13

Linens, wood, or liquids

Question 14

Storage of heat-sealed plastic wrap for ethylene oxide

Answer 14

one year

Question 15

Storage of paper wrapping with ethylene oxide

Answer 15

30-60 days

Question 16

Cloth wrapping with ethylene oxide

Answer 16

15-30 days

Question 17

How long can instruments be stored for when sealed in plastic wrap with tape after being sterilized with EtO

Answer 17

90-100 days

Question 18

Disadvantages of ethylene oxide sterilization

Answer 18

flammable so usually mixed with CO2 or hydrochlorofluorocarbon
Glass resists penetration
Absorbed by rubber and plastics - aeration needed
Time - 2-5 hours

Question 19

What are the three types of sterilization indicators

Answer 19

Physical - Print outs or graphs verifying temp and time
Chemical - Class 1-6
Biologic - Check viability of bacterial colonies on a culture after processing

Question 20

What are class 5 and class 6 indicators

Answer 20

Class 5 - react to all parameters that are important to a given type of sterilizer
Class 6 - react to more specific guidelines to combat prion infection

Question 21

Describe class 5 indicators

Answer 21

React to all parameters that are important to a given type of sterilization (except prions)

Question 22

Describe class 6 indicators

Answer 22

React to more specific guidelines to combat prion infection

Question 23

Which of the following has the most residual activity? Triclosan, Alcohol, Iodine, or Chlorhexidine

Answer 23

Chlorhexidine

Alcohol has none
Triclosan an intermediate amount
Iodine a moderate amount

Question 24

What are the advantages of Povidone-iodine?

Answer 24

safe in the ears, mouth and eyes

Question 25

Bactericidal/-static status of chlorhexidine

Answer 25

Bactericidal at high concentrations
Bacteriostatic at low concentrations

Question 26

What percentage of chlorhexidine solution can be used in wounds?

Answer 26

<0.05%

Question 27

Spore activity of chlorhexidine

Answer 27

Poor against spores unless at high temperatures

Question 28

Is chlorhexidine ototoxic in the middle ear?

Answer 28

yes