sterilization and its methods, department of central sterilization and its maintenance

Question 1

what is sterilization?

Answer 1

Sterilization: process by which all living organisms are eliminated, including bacterial spores, in order to achieve asepsis.

Different from:
• Disinfection: process of elimination of pathogenic MIO, but spores may still remain.
• Decontamination: process of removal of contaminating pathogenic MIO from articles by a process of sterilization or disinfection.

Question 2

Physical means:

Answer 2

• 1) Burning, Boiling, Boiling with overpressure.
• 2) Steam under pressure – autoclave.
• 3) Hot air, X-ray - gamma rays 25k Gy, UV light.
• 4) Filtration.
• 5) USG – now more for mechanical cleaning.
• 6) Plasma.

Question 3

Chemical means:

Answer 3

• 1) “Cold” sterilization.
• 2) Difference from disinfection: all germs are destroyed.
• 3) Ethylenoxide.
• 4) Peracetic acid.
• 5) Formaldehyde.

Question 4

general demands

Answer 4

• All microbes must be destroyed.
• Don´t destroy objects.
• Objects have to be packed – sacs have pores big enough for penetrating steam / ethylene-oxide, Peracetic acid, but not big enough for MIO´s.
• toxic remnants must not remain on objects.
• Cost effective.

-Making controls → taking samples.

-Department of central sterilization:
▪ Equipment is expensive & specialized trained staff is needed.
▪ Cleaning (follow specialized protocol).
▪ Sterilization.

Question 5

two types of sterilization

Answer 5

dry heat - oxidation

wet heat - coagulation of proteins

Question 6

which chemical is carcinogenic?

Answer 6

ethylenoxide

Question 7

Lemaire came up with:

Answer 7

carbolic acid destroys MIO’s

Question 8

Lister said:

Answer 8

open fractures are prone to sepsis

Question 9

which came first?

Answer 9

antisepsis

then sepsis

Question 10

Filtration of air is:

Answer 10

not effective against viruses

Question 11

bio indicators and bacteriological testing

Answer 11

are viable microorganisms that are resistant to a specific sterilization. They help monitor whether the necessary conditions were met to kill a specified number of microorganisms for a given sterilization process

Question 12

Ultrasonic cleaner

Answer 12

uses ultrasound to agitate a fluid.

• surface of cells is destroyed
• mechanical cleaning of instruments

Question 13

plasma is

Answer 13

o Cold sterilization.
o Very low pressure.
o Plasma is developed by mean of electrical field.
o 3-5 min.

Question 14

ethylenoxide

Answer 14

mixed with CO₂ (10% E, 90% CO₂)

• toxic, carcinogenic, explosive.
• also objects in sacs are sterilized.

Question 15

Steams of Peracetic acid:

Answer 15

• only surface. - submersion / in atmosphere. - glass, rubber, plastics, metals.

Question 16

steams of formaldehyde

Answer 16

used as fixation for microscopes

Question 17

burning

Answer 17

• safe but objects are destroyed too

- bacteriological/inoculation loop used in microbiology

Question 18

Boiling:

Answer 18

spores are resistant

Question 19

boiling with over pressure

Answer 19

• papin’s pot in which the autoclave is modeled after

- cleans metal and rubber

Question 20

Steam under pressure (autoclave):

Answer 20

kills bacteria, viruses, fungi at 134 deg. for 3 minutes or 121 deg for 15 min

Question 21

X-rays:

Answer 21

• no effect on viruses
• 25 000 Gy
• expensive
• sterilizing syringes

Question 22

uv rays

Answer 22

sterilizes air in operating theatre

Question 23

glutaraldehyde

Answer 23

2%

• used for endoscopic instruments
• reused several times during endoscopic sessions

Question 24

Etyleneoxide gas

Answer 24

heat sensitive material, plastic, endoscope, electrical equipment