STERILIZATION & DISINFECTION.pptx..........

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1. M.M COLLEGE OF NURSING MULLANA, AMBALA STERILIZATION AND DISINFECTION ANU KAUSHAL NURSING TUTOR MSN DEPTT.

2. STERILIZATION Sterilization is a process by which all living microorganisms including viable spores, are either destroyed or removed from an article, surface or medium. The agents which achieve sterilization are called as sterilants.

3. DISINFECTION It refers to a process that destroys or removes most if not all pathogenic organisms but may or may not destroy bacterial spores. They are normally used only on inanimate objects, not on body surfaces. The agents which achieve disinfection are called as disinfectants.

4. FACTORS AFFECTING EFFICACY Organism load. Nature of organism Concentration Contact time Temperature Stability Local Ph Relative humidity Organic matter

5. SPAULDING CLASSIFICATION

6. TYPES OF DISINFECTANTS Depending upon their efficacy, thedisinfectants are further classified into three categories. High-level disinfectants (HLD) Intermediate-level disinfectants (ILD) Low-level disinfectants (LLD).

7. High-level disinfectants (HLD) agents are capable of killing bacterial spores when used in sufficient concentration under suitable conditions. They can kill all the other microorganisms. Aldehyde Formaldehyde, glutaraldehyde and ortho- phthalaldehyde are the commonly used disinfectants. They combine with nucleic acids, proteins and inactivate them, probably by cross-linking and alkylating the molecules.

8. Glutaraldehyde Semi critical items: It remains active in the presence of organic matter and is non-corrosive to equipment. Therefore, glutaraldehyde is the most common HLD used for semi critical equipment, such as endoscopes and cystoscopes. It is used at 2% or 2.4% concentration (e.g. Cidex). It disinfects objects within 20 minutes but may require longer time to kill spores (10-14 hours). It is available in inactive form; has to be activated by alkalinization before use. Once activated, it remains active only for 14 days.

9. Aerial disinfection and cleaning: It is also used for fogging and cleaning of floor and surfaces of critical areas such as operation theatre (e.g. Bacillocid Extra) Advantages : It remains active in the presence of organic matter, has excellent material compatibility Disadvantages : It has a pungent odor, can produce eye irritation, occupational asthma and contact dermatitis .

10. Ortho-phthalaldehyde (0.559%)This can also be used for disinfection of semicritical items, has many advantages over glutaraldehyde-(1) it does not require activation, (2) better odor, (3) less eye irritation, (4) acts faster (5-10 min). However, it does not kill spores effectively and stains skin gray.

11. Formaldehyde: Although it is an excellent HLD, the health- care uses of formaldehyde are limited because it produces irritating fumes and pungent odor and also a potential carcinogen. It was used for fumigation of closed areas, such as operation theater, but now this is an obsolete practice.

12. Peracetic Acid : Peracetic acid is used in automated machines. It is also available for manual immersion; 0.1- 0.2%, used for 5-15min . Use : It can be used to sterilize medical (e.g. endoscopes, arthroscopes), surgical and dental instruments. Peracetic acid in combination with hydrogen peroxide has been used for disinfecting hemodialyzers Disadvantages : Expensive, has material compatibility issues, causes chemical irritation and eye damage.

13. Hydrogen Peroxide ( H 2 O 2 ) works by producing destructive hydroxyl free radicals that can attack various cell components. Uses : HO, has several usages at various concentrations. It is sporicidal only at >4-5% 3% , is used for environmental surface disinfection, fogging and for wound cleaning.

14. 3-6 % is used to disinfect soft contact lens, tonometer biprisms, ventilators, fabrics, and endoscopes, etc. 6-7.5 % is used as chemical sterilant in plasma sterilization. Vaporized is used for industrial sterilization of medical devices and for decontamination of large and small area.