Sterilization and Disinfection

Question 1

sterilization

Answer 1

destruction of all microorganisms in or about an object

Question 2

cleaning is accomplished by what two things

Answer 2

• detergent mixed with water

- mechanical action

Question 3

Why is it not ok to mix disinfectants?

Answer 3

chemical compounds can react when mixed

Question 4

What is shelf life?

Answer 4

period of time between activation of solution and disposal

Question 5

How long does disinfection take?

Answer 5

20minutes of exposure at room temperature

Question 6

How long does it take for an item to be rendered sterile?

Answer 6

10 hours of immersion

Question 7

4 methods of removing bio burden

Answer 7

• chelation: binding minerals to prevent deposit
• enzymatic: catalyst for breaking down organic soil
• emulsification: dispersing two liquids not capable of being mixed
• solubilization: solubility of substance increased within a solution

Question 8

What must items such as endoscope be rinsed with after soaking in disinfectant solution?

Answer 8

• sterile water*

- not distilled

Question 9

4 recommendations for decontamination in machine?

Answer 9

• instruments in perforated wire mesh tray
• heavier instruments on bottom/not on delicate instruments
• hinged instruments left open allowing solution contact on entire surface area
• instruments with attachments disassembled

Question 10

Characteristics of ultrasonic cleaner

Answer 10

• uses cavitation to clean instruments*

- removes small organic particles not reached by manual/mechanical means

Question 11

Product Associated Parameters (5)

Answer 11

• bioburden: degree of contamination with microorg. and org. debris
• bioresistance: factors heat and/or reproductive phase of micro organisms
• biostate: nutritional, physical, reproductive phase of microorganisms
• density: factors affecting penetration and evacuation of instrument

Question 12

Process Associated Parameters

Answer 12

• temperature
• humidity/moisture/hydration
• time
• purity of agent/air/residual effects/residue
• saturation/penetration
• capacity of sterilizer/position of items

Question 13

general principle of packaging

Answer 13

• muslin wrap*
• max size: 12high/12wide/20long inches
• not exceed 12 pounds

Question 14

Special instruction for cleaning instruments with lumens

Answer 14

leave residual amount of distilled water in lumen to prevent entrapment of air

Question 15

Special instruction for cleaning basins

Answer 15

• separated by porous material
• sponges/linen not inside basin
• placed on lowest shelf, not bottom
• 250f min 20min

Question 16

What happens when woven wrapped item becomes unsterile?

Answer 16

item must be unwrapped and completely reprocessed including re-washing h

Question 17

chemical indicators

Answer 17

does not establish sterility/ only process
-external indicator:
-tape
-label
-paper strips
…that change color

Question 18

bacterial spores for biological monitoring

Answer 18

• bacillus stearothermophilus:
• STEAM UNDER PRESSURE*
• bacillus subtilis:
• dry heat
• hydrogen peroxide plasma
• ETHYLENE OXIDE*

Question 19

sterilizing methods

Answer 19

• thermal

- chemical

Question 20

what two factors kill microbes?

Answer 20

moisture/heat

Question 21

How long does it take for bacillus stearothermophillus at 250degrees?

Answer 21

12min

Question 22

why is pressure necessary?

Answer 22

raises temperature of steam

Question 23

Precautions taken when loading sterilizer?

Answer 23

• flat packages placed on edge
• small packages placed on top of each other are criss crossed
• basins placed on sides

Question 24

What is flash sterilization?

Answer 24

process of sterilizing unwrapped items such as instruments that have been dropped

Question 25

Steam Sterilization Minimum exposure, temperature, pressure and times

Answer 25

mixed load: 10minutes at 270

metal/no porous/no lumens: 3min 270

Question 26

minimum pounds of pressure required for steam sterilization

Answer 26

27psi

Question 27

what factors influence Ethylene Oxide sterilization

Answer 27

• 85-145* degrees Fahrenheit
• time
• gas concentration
• humidity
• kills microorganisms by interfering with metabolism of protein*

Question 28

What is dry heat used to sterilize?

Answer 28

• oil, petroleum products, talc
• involves coagulation of microbe proteins
• higher temp required in absence of moisture

Question 29

what is used in ionizing radiation?

Answer 29

COBALT 60

Question 30

disadvantages of Hydrogen Peroxide

Answer 30

• metal trays block radio frequency waves and cannot be used
• no compatible with paper
• not approved for use on flexible endoscopes