infection control

nosocomial

hospital accquired

what percent of mechanically ventilated patients develop pneumonia?

9-27%

What is the objective of infection control procedures?

eliminate the sources

create barriers to transmission

monitor the effectiveness of control

3 elements present to spread infection

source, route, host

when is someone most susceptible host?

when endorphins are low (stress, anger)

examples of sources

people, contaminated equipment, medications, catheters, tubes, lines

what is the origin of most nosocomial infections?

improper hand washing

3 major routes of transmission

contact

droplet

airborne

what is contact direct

body surface to body surface contact. pathogen transferred from person to person

what is indirect contact?

most frequent

occurs between host and inanimate object

examples of indirect contact

clothing, eating utensils, drinking glass, respiratory equipment, toys, inadequately processed equipment

examples of contact pathogens

hiv

std

hepatitis a,b,c

c diff

staphylococcus

polio

example of droplet pathogens

influenza

rubella

adenovirus

strep

pertussis

menigitis

SARS

covid

RSV

airborne

spread of contaminated dust particles or evaporated water droplets

size of droplet nuclei

less than 5um

examples of airborne

common cold, legionellosis, tb, fungal infections, measles, chickenpox, influenza, pertussis

what precautions should be implemented for covid?

contact and droplet

common vehicle

pathogens transmitted by contaminated food, water, medication

vector borne

animal or insect transfers the pathogen to the host

who is more susceptible for being a host?

immunocompromised, diabetics, obesity, copd, smokers, elderly, lines, drains, airways, surgical incisions

colonization

the presence of microorganisms w/o causing symptoms, disease, or detectable immune response

antiseptic

chemical agent applied to living tissue to kill microbes

pasteurization

the use of heat at a temp sufficient to inactivate pathogenic organisms in liquid (less heat than needed for sterilization)

sterilization

the complete killing or removal of all living organisms from a location or material

are there graduations in sterility?

no

iodophors

combination of iodine and a solubilizing agent or carrier the resulting complex provides a sustained release reservoir of iodine and releases small amounts of free iodine in aqueous solutions

critical items

high risk of infection if such an item is contaminated with any microorganism including bacterial spores

examples of critical items

cardiac and urinary items, implants, arthroscopes, laparoscopes, surgical instruments

if a object is heat sensitive what would it be treated with?

ethylene oxide, hydrogen peroxide, of liquid chemical sterilant

semi critical items

contact mucous membranes or nonintact skin

examples of semi critical

rt and anaesthia equipment

endoscopes

esophageal manometry probes

methods of sterilization

heat, radiation, chemical methods

dry heat

simplest method, expose the item to naked flame

only to items that will be damaged to moist

common temp time for dry heat

170 for 60 min

160 for 120 min

150 for 150 mins

moist heat

basic principle of steam sterilization as accomplished in autoclave

4 parameters of sterilization

steam

pressure

temperature

time

UV light

limited sterilization power because of poor penetration into most materials

ionizing radiation

typically by cobalt 60 gamma rays, is a low temp sterilization method

Ethylene Oxide (ETO)

colorless gas flammable and explosive

4 parameters that influence effectiveness of ETO sterilization

Gas Concentration (450-1200)

Temp (37-63)

relative humidity (40-80%)

exposure time (1-6 hrs)

what factors influence the activity of disinfectants

proportional to temp

time

range of action

may be inactivated by: dirt, organic matter, proteins, blood, mucus