SterilizationPhysical Heat dry & moist FiltrationIrradiation Chemical

Definition Sterilization: The freeing of an article from all living organisms including bacteria and their spores. Disinfection: Removal of some types of pathogenic organisms usually not including spores.

DISINFECTANT : Chemical substances used for sterilization of inanimate objects (toxic to human) ANTISEPTIC : Chemical substance that used for sterilization of animate objects (not toxic to human) Chemical Mehods

Disinfectants Low level disinfectant Intermediate level disinfectant High level disinfectant

Destroys 1. All vegetative bacteria (except tubercle bacilli) 2. Enveloped viruses 3. Some fungi Examples 1. Phenol group 2. Quaternary ammonium compound

Phenol Mouth washes Scrub soaps Surface and household disinfectants Phenol 5% used as disinfectant of stool in typhoid or sputum in T.B

Quaternary ammonium compound Surface disinfectant Contraindicated as antiseptics

Destroys All vegetative bacteria (including tubercle bacilli) Enveloped and some non-enveloped viruses Most fungi Examples Alcohol Hydrochlorites Iodine and iodophores

Alcohol Examples: 1. Ethyl alcohol 2. Isopropyl alcohol Uses: 1. Topical antiseptics 2. Disinfect the surface of medical equipment

Hypochlorite Examples :  Clorox Uses :  Household bleach  Surface disinfectant  Water disinfectant

Iodine and Iodophore disinfectants 1. Antiseptic 2. Disinfection of blood culture bottles 3. Disinfection of medical equipments such as thermometers and endoscopes

Destroys All vegetative bacteria (including tubercle bacilli) Enveloped and some non-enveloped viruses Fungi Some bacterial spores Examples H2O2 Gluteraldehyde Formaldehyde Peracetic acid

H2O2 Mouth gurgle Antiseptic to clean wounds

Gluteraldehyde Example:  Cidex Uses:  Very potent disinfectant Disadvantages:  Highly toxic used under trained supervision in a well ventilated setting and with appropriate personal protective equipment

Formaldehyde Example:  Formalin, formadon Uses:  Disinfectant in both liquid and gaseous state Disadvantages:  Potential carcinogen

ClassificationItemsExamplesReprocessing Critical items (high risk) Items that penetrate soft tissues Surgical Instruments IUD Vascular catheters implants cleaning followed by sterilization Semicritical items (intermediate risk) Items that in close contact with mucous membranes or with non intact skin Respiratory equipments, flexible endoscopes, laryngoscopes, endotracheal tubes, thermometers,. Cleaning followed by high level disinfection Non critical item (low risk) Items that come in contact with normal and intact and inanimate environment skin Stethoscope Walls, floors, ceiling, Furniture, sinks. Cleaning and /or low level disinfection

ItemMethod of sterilization Cat gutIonizing radiation Endoscopes2% Gluteraldehyde 30 min, 10% phenol 6 hrs, ethylene oxide Disposable syringesEthylene oxide, ionizing radiation Egg/serum mediaInspissation (80 o C,30 min, for 3 days) Faeces, urine, vomitusBleaching powder, cresol Heart-lung machineEthylene oxide Endoscope washer

ItemMethod of sterilization Infected materialsIncineration Lab mediaAutoclave(121 o C, 20min) Oils, powders, glasswareHot air oven (160 o C 2 hrs, 180 o C 1 hr) Operation theatre/roomFormaldehyde gas Plastic/polythelene tubesEthylene oxide, 2% gluteraldehyde Serums, fluidsWater bath( 56 o C, 1 hr) SkinTincture iodine, 70% methylated alcohol(spirit), savlon

ItemMethod of sterilization SputumBurning, autoclave Suture materialAutoclave Thermometer, cheatle forceps10% chlorhexidine+ cetrimide 1% for 10 min Toxins, antibiotic solutions, blood products Filtration VaccinesVaccine bath (60 o C, 1 hr) Surgical instrumentsH2O2 gas plasma Autoclave Infra-red (metal instruments) GownsAutoclave