Looks like no one added any tags here yet for you.
Disinfection
killing of many, but not all, microorganisms
corrosive phenol-containing compounds
used only on inanimate objects
ethanol and iodine
used on skin surfaces
Antiseptics
Chemicals used to kill microorganisms on the surface of skin and mucous membranes
Antiseptics
chemicals intended to reduce or destroy microorganisms on living tissue
Levels of Disinfection
HIGH-LEVEL DISINFECTION
INTERMEDIATE-LEVEL DISINFECTION
LOW-LEVEL DISINFECTION
HIGH-LEVEL DISINFECTION
The destruction of all viruses, vegetative bacteria, fungi, mycobacterium, and some, but not all, bacterial spores
INTERMEDIATE-LEVEL DISINFECTION
The destruction of all mycobacteria, vegetative bacteria, fungal spores, and some nonlipid viruses, but not bacterial spores
LOW-LEVEL DISINFECTION
A process that can kill most bacteria (except mycobacteria or bacterial spores), most viruses (except some nonlipid viruses), and some fungi
Sterilization
killing or removal of all microorganisms, including bacterial spores, which are highly resistant
Antibiotics
taken inside
Sterilization
taken outside
Sterilization
usually carried out by autoclaving
121 Celsius
15 lb/in2 for 15 minutes
Ethylene oxide
a low temperature gaseous process widely used to sterilize a variety of healthcare product
Ethylene oxide
disrupts cellular metabolism and reproductive processes of microorganisms
Ethylene oxide
penetrates breathable packaging
Ethylene oxide
suitable for the sterilization of a wide range of materials
Filtration
Intravenous solutions are sterilized by
Chemicals
vary greatly in their ability to kill microorganisms
Chemical agents
act primarily by one of the three mechanisms:
1. Disruption of the lipid-containing cell membrane
2. Modification of protein
3. Modification of DNA
Ethanol
widely used to clean the skin before immunization or venipuncture
Ethanol
more effective at 70%
Alcohol with water is more effective compared to alcohol alone
Detergents
“surface-active” agent composed of long-chain, lipid soluble, hydrophobic portion and a polar hydrophilic group, which can be a cation, an anion, or a nonionic group
Detergents
They interact with the lipid in the cell membrane through their hydrophobic chain
Phenol
the first disinfectant in the operating room (by Lister in the 1860s), but it is rarely used as a disinfectant today because it is too caustic
Hexachlorophene
a biphenol with six chlorine atoms, is used in germicidal soaps, but concern over possible neurotoxicity has limited its use
Cresol
the active ingredient in Lysol
Chlorine
used as a disinfectant to purify the water supply and to treat the swimming pool
Chlorine
active component of hypochlorite (bleach, Clorox), which is used as a disinfectant in the home and in hospitals
Chlorine
a powerful oxidizing agent that kills by cross-linking essential sulfhydryl groups in enzyme that form the inactive disulfide
Iodine
most effective skin antiseptic used in medical practice and should be used prior to obtaining a blood culture and installing intravenous catheters because contamination with skin flora such as Staphylococcus epidermis can be a problem
Tincture of iodine
(2% solution of iodine and potassium iodide in ethanol) is used to prepare the skin prior to blood culture
Iodophors
complexes of iodine detergent that are frequently used to prepare the skin prior to surgery because they are less irritating than tincture of iodine
Iodine
an oxidant that inactivates sulfhydryl-containing enzyme
Mercury and silver
the greatest antibacterial activity of the heavy metals and are the most widely used in medicine
Mercury and silver
They act by binding to sulfhydryl groups, thereby blocking enzymatic activity
Thimerosal and merbomin
which contains mercury, are used as skin antiseptics
Silver nitrate
useful in preventing gonococcal ophthalmia neonatorum
Silver sulfadiazine
used to prevent infection of burn wounds
Hydrogen peroxide
used as an antiseptic to clean wounds and to disinfect contact lenses
Hydrogen peroxide
oxidizing agent that attacks sulfhydryl groups, thereby inhibiting enzymatic activity
Formaldehyde
a 37% solution in water (Formalin), denatures protein and nucleic acids
Glutaraldehyde
10 times more effective than formaldehyde and is less toxic
Ethylene oxide
used extensively in hospitals for sterilization of heat sensitive materials such as surgical instruments and plastics
Strong acids and alkalis
kill by denaturing protein
Dyes
not only stain microorganisms but also inhibit their growth
Crystal Violet
which is used as a skin antiseptic
Malachite Green
a triphenylamine dye like crystal violet, is a component of Löwenstein-Jensen’s medium
e dye inhibits the growth of unwanted organisms in the sputum during the 6-week incubation period
Heat
kills by denaturating proteins, but membrane damage and enzymatic cleavage of DNA may also be involved
Moist-heat
sterilizes at lower temperature than dry heat
usually autoclaving, is the most frequently used method of sterilization
Dry Heat
requires temperatures in the range of 180 C for 2 hours
used primarily for glassware and is used less frequently than autoclaving
Pasteurization
technically not a sterilization process
used primarily for milk, consist of heating the milk to 62 C for 30 minutes
sufficient to kill the vegetative cells of the milk borne pathogen
UV Light
250- 260 nm
maximum absorption by the purine and pyrimidine base of DNA
UV Light
inhibits the DNA replication and the organism cannot grow
UV Light
used in hospitals to kill airborne organisms, especially in operating rooms when they are not in use
Bacterial spores
quite resistant and require a dose up to 10 times greater than the vegetative bacteria
X-rays
have higher energy and penetrating power than UV radiation
X-rays
used in medicine for sterilization of heat sensitive items, such as sutures and surgical gloves, and plastic items, such as syringe
Filtration
preferred method of sterilizing certain solution
Pyrogen
chemicals or agents that can increase fever
Filtration
nitrocellulose and has a pore size of 0.22µm
work by physically trapping particles larger than the pore size