1-8 Control of Microorganisms: Infection Control, Sterilization, and Disinfection Flashcards
Type of isolation for patient diagnosed with MRSA pneumonia?
Contact isolation
Chain of infection
Transmission occurs when the agent leaves its reservoir or host through a portal of exit, is conveyed by some mode of transmission and enters though an appropriate portal of entry to infect a susceptible host
HAI’s are associated with several risk factors
Hospital associated infections
use of indwelling medical devices
tranmissions between patients and workers
surgical procedures
endoscopes
nosocomial infections
single best way to prevent nosocomial infections?
soap and water
standard precautions
§ Clean hands, cover mouth/nose with arm/tissue, wear gown/glove/mask/eye protection as needed.
airborne precautions
Used for patients known or suspected to be infected with microorganisms transmitted by small-particle residue of droplets (
droplet precautions
for patients known/suspected infected with microorganisms transmitted by droplets less than 5uM generated by coughing or sneezing
Use of surgical masks and gown when entering room along with hand washing.
Contact Precautions
§ Used for patients known or suspected to be infected or colonized with epidemiologically important microorganisms that can be transmitted by direct contact with the patient or indirect contact with patient’s environment surfaces or patient-care items used.
□ MRSA, scabies, wounds or abscesses with uncontained drainage
Use gown when entering room and alcohol based hand washing products allowed
o Contact PLUS Precaution
§ Used for patients known or suspected to have serious illnesses easily transmitted by direct patient contact or by contact with items and surfaces in the patient’s environment.
□ C. diff, noro/rotavirus/E. coli, salmonella or other enteric infections
□ Hand hygiene with soap and water (not alcohol-why is this?) and room must be disinfected with bleach
Reverse (protective) isolation
§ A method to prevent a patient in a compromised health situation from being contaminated by other people or objects
□ Neutropenic patients with reduced immune function from chemotherapy (reduced WBC count)
Individuals entering room wear mask, gloves, and gown.
sterilization
Results in the complete destruction of all forms of microbial life, including bacterial and fungal spores
o Living tissue cannot be sterilized
Disinfection
Results in the destruction of specific pathogenic microorganisms-does not necessarily result in sterilization
Kills nearly all microorganisms except bacterial spores
Decontamination
Removal of debris, blood, and proteins-and most microorganisms-not necessarily rendering the device “safe to handle” by HCWs who are not wearing protective attire.
Antisepsis
An agent is one that has been formulated for use on skin or mucous membranes to prevent or inhibit the growth of microorganisms. (Antiseptics should NOT be used to decontaminant inanimate objects).
Reduction of microorganisms on living tissue/skin…this can be both external or internal surfaces
Can also be used on inanimate objects related to medical/surgical care
critical items
instruments that come into contact directly with blood stream
physical methods are used to sterilize
semi-critical items
non-invasive flexible. come into contact with mucous membranes
high level disinfectant
noncritial items
do not ordinarily touch patient or only skin
no contact with mucous membranes
Dry heat
flaming, incineration, hot air oven, infrared
moist heat
above, at, or below 100
autoclaving is most common way to sterilize inanimate objects in health care
higher pressure - better penetration. cant be used for oil and rubber items
radiation
causes damage to nucelic acids
single use medical supplies
irradiated RBC
help fight graft vs host disease GVHD
filtration
good to sterilize solution of heat sensitiee materials
chemical
liquid or gas
alcohols are the
most common method of disinfection in health care
glutaraldehyde
sterilize hospital instruments
only liquid chemical disinfectant that can be considered a sterilant
hydrogen peroxidde
acts on microorganisms through release of nascent oxygen, produces free radicals that damage proteins and DNA
PAA
acetic acid + hydrogen peroxide
disinfects by oxidizing outer cell membrane of vegetative cells, endospores
PAA uses
cooler tower water disinfectant to prevent biofilms and control legionella
plasma sterilization - beneficial for sterilizing temperature snestive polymeric material like endoscopes
