Ch. 17: Equipment Decontamination and Infection Control Flashcards
Define vegetative organisms.
Organisms in active growth.
These organisms pose the greatest hazard for infection via respiratory therapy equipment because the most common equipment con- taminants are not spore-forming bacteria.
Organisms in a resting, resistant stage
Spores
True or False.
Spores are very difficult to kill but pose little threat for infection via respiratory therapy equipment. Examples of spore-forming bacteria are Clostridium and Bacillus.
True
What is the killing of all vegetative forms of organisms but not spores called?
Disinfection
What is the killing of all organisms, both vegetative and spores called?
Sterilization
An agent that sterilizes equipment is called a _____.
sterilant
The suffix -cidal means to ____.
Kill
Define bactericidal
Something that kills bacteria
The suffix -static means __________.
To prevent growth of
Gram-positive bacteria stain what color?
Purple-black color
Gram-negative bacteria stain what color?
Pink
Define nosocomial infection.
A hospital-acquired infection.
Often caused by Pseudomonas species, Staphylococcus species, Candida albicans, or E. coli.
CHEMICAL CONCENTRATION
The more concentrated a chemical is, the more ______.
rapid the action
The more intense a physical agent (e.g., heat), the more _________.
rapidly the organisms are killed
The longer the organisms are exposed to the agent, __________.
The greater the number killed.
Increasing the temperature of a chemical agent ________ the exposure time required to kill the organisms.
Shortens
What is sphere-shaped bacteria called?
Cocci
What is spiral-shaped bacteria called?
Spirillum
What is rod-shaped bacteria called?
Bacilli
What is the most frequent encountered bacteria on respiratory equipment?
Bacilli
Are bacilli spore-forming bacteria?
No.
List some examples of bacilli
a. Klebsiella pneumoniae: a gram-negative bacillus
b. Pseudomonas aeruginosa: a gram-negative bacillus
c. Mycobacterium species: a gram-positive bacillus
and causative agent of tuberculosis (TB)
d. Legionella species: gram-negative bacilli
e. Serratia marcescens: a gram-negative bacillus
and secondary invader in respiratory and burn
patients
f. Haemophilus influenzae: a gram-negative
bacillus
The aforementioned gram-negative organisms are often responsible for necrotizing forms of pneumonia.
A gram-positive bacillus
and causative agent of tuberculosis (TB)
Mycobacterium species
The presence of blood, sputum, or other medium provides protection for the organisms. ** It is for this reason that equipment must be thoroughly washed in soapy water and rinsed off before the decon- tamination process.**
Okay!
Autoclave (steam under pressure)
What are normal operatin levels?
Normal operating levels are 15 min at 121° C and 15 psig (2 atm).
What is one of the most dependable and practical methods for decontamination?
Heat in the form of steam
Autoclave (steam under pressure)
How does autoclave (steam under pressure) kill organisms?
Kills organisms by coagulation of the cell
protein.
What material cannot stand the intense heat of autoclaving?
Bacteria filters are commonly sterilized by this method, but any material made of rubber cannot withstand the intense heat.
How should equipment be prepared before being autoclaved?
Equipment to be autoclaved must be thoroughly washed in soapy water, dried, and wrapped in muslin, cloth, or a paper bag.
Explain pasteurization.
Equipment is immersed in hot water at 60° to
70° C for 20 to 30 minutes.
The hotter the water, the less time needed to clean the equipment.
Does pasteurization kill spores?
Pasteurization disinfects equipment, but spores are not killed.
Ethylene oxide gas sterilization
Why must equipment must be washed in soapy water, rinsed, and dried completely before being placed in the sterilization chamber?
If equipment is not completely dry before the
sterilization process, ethylene oxide combines with water to form ethylene glycol, an irritating substance found in antifreeze.
Sterilizes or disinfects?
Ethylene oxide kills all organisms including spores; therefore it ________ equipment.
Sterilizes
Does acetic acid (vinegar) disinfect or sterilize equipment?
Acetic acid kills vegetative bacteria but not spores; therefore it disinfects equipment.
Acetic acid (vinegar) is very effective against what species?
Pseudomonas
Cidex solution remains active for ____ days.
28
What is the most common glutaraldehyde product?
Cidex, which is an alkaline glutaraldehyde
solution.
Ethylene oxide gas sterilization
It is a highly flammable gas, but when it is mixed with approximately ________, the explosive danger is minimized.
90% carbon dioxide or freon
Ethylene oxide gas sterilization
Equipment may be processed in one of two ways:
(1) Warm gas: 50° to 56° C for 4 hours
(2) Cold gas: 22° C (room temperature) for 6
to 12 hours
** Ethylene oxide gas sterilization**
After exposure to the gas, the equipment must be aerated for about ________ at 50° to 60° C.
12 hours
Most respiratory therapy equipment can be decontaminated by this method.
Ethylene oxide gas sterilization
Ethylene oxide gas sterilization
The recommended gas concentration is __________.
800 to 1000 mg/L.
Because moisture enhances the action of
ethylene oxide, it is recommended that the relative humidity within the sterilizing chamber be maintained at ______.
50% or more
Ethylene oxide gas sterilization
Items placed in sealed plastic bags are suitable for use for up to________ after gas sterilization, provided the bag is intact.
1 year
What type of alcohols are the most
commonly used in the clinical setting?
- Ethyl alcohol (95% concentration)
- Isopropyl alcohol (70% concentration)
Do alcohols disinfect or sterilize?
Alcohols are bactericidal and fungicidal but not
sporicidal; therefore they disinfect (but do not sterilize) equipment.
How do alcohol kill organisms?
Alcohols kill organisms by destroying the cell protein.
Alcohols
Action is decreased when diluted below what percent?
50%
When are glutaraldehydes bactericidal?
in 10-15 minutes
When are glutaraldehydes sporicidal?
3-10 hours, depending on the temperature of the solution
________ is used as a disinfectant for home
care equipment and is often run through room humidifiers for cleaning purposes. It is no longer recommended for cleaning the equipment of CF patients.
Acetic acid (vinegar)
IMPORTANT POINTS CONCERNING DECONTAMINATION OF EQUIPMENT
Always date the container that holds the solution
after it is opened; solutions should be discarded after _______.
24 hours
This reduces the possibility of filling a reservoir with contaminated solution.
Condensation in the delivery tubing should never be drained back into the reservoir.
Condensation in the delivery tubing should never be drained back into the reservoir.
Provide a method of routine surveillance to determine the effectiveness of the decontamination process. This is referred to as __________.
Quality control of equipment
Ensuring that the equipment is sterile is best accomplished with which indicator?
Biological
What type of indicator is this?
Strips of paper impregnated with bacterial spores are placed in a glass ampule that contains a growth medium. The ampule is then placed inside the sterilizer. After the sterilization process is complete, the ampule is broken and the spore strip is exposed to the growth medium. After an incubation period, if the spore strip changes color, bacteria are present and the sterilization process was ineffective.
Biological indicator
What type of indicator is this?
Impregnated on packing tape and change color when exposed to certain conditions. Autoclave and ethylene oxide sterilization both use this type of indicator. These indicators show that the package went through the sterilization process but do not necessarily indicate that the equipment is sterile.
Chemical
What is the most cost-effective method of preventing cross contamination of equipment among patients?
Proper handwashing techniques
How should equipment taken out of an isolation room be handled?
All equipment and supplies taken from an isolation area must be double bagged in nonporous plastic bags.
Handling of contaminated equipment:
The bag should be labeled to indicate that it is from an isolation area. Labeling should also identify the bag contents as well as the patient’s name and room number. The labeling procedure may vary by institution.
Okay.
INFECTION CONTROL AND STANDARD PRECAUTIONS
Hand washing: should be done for ________ before and after visiting every patient, even if the examiner is wearing gloves.
15 seconds
What are the three types of transmission-based precautions?
- Precautions against contact
- Precautions against airborne infections
- Precautions against droplet spreading
Alcohol-based hand sanitizers that do not require the use of water are preferred over soap and water because of ________________. Hand sanitizers are also more convenient and reduce the potential drying of the skin.
their superior antimicrobial action
What type of precaution is this?
To further aid in the reduction of airborne organisms, a special (negative pressure) ventilation system should be in place in the room so that air is safely discharged or recirculated in the room through a HEPA filter.
Precautions against airborne infections
If private rooms are not available for patients under these three types of special precautions, patients infected with the same organism may share a room. This is referred to as ______.
Cohorting
Examples of diseases transmitted by droplet contact
- H. influenzae infection
- Streptococcal pneumonia
- Epiglottitis
- Pertussis
- Meningitis,
- Adenovirus infections.
What is the difference between droplet and airborne precautions?
The difference between droplet precautions and airborne precautions is that droplet precautions focus on the spread of infectious organisms through mouth, nose, and conjunctival areas, while airborne precautions focus on the prevention of entry through the respiratory system. Droplet precautions are typically not a concern if over 3 feet away.
Examples of diseases transmitted by droplet contact
- Tuberculosis
- Legionellosis
- Avian flu
- Varicella
- Measles
- Small pox
- Severe acute respiratory syndrome (SARS)
Examples of diseases transmitted by contact
- Hepatitis
- AIDS
- Venereal diseases, and resistant staphylococcal infections such as MRSA.
