Download to read offline
More Related Content
Similar to Disinfection (dr.sumesh)
![[Micro] chemical sterilizaton](https://cdn.slidesharecdn.com/ss_thumbnails/xwi6imyrrchg97geohxj-signature-2127a2ca5368c7fdfd023e8d90dde3fc0b9fe7d91346a4189562c9f63dc0d19d-poli-150819190754-lva1-app6891-thumbnail.jpg?width=640&height=640&fit=bounds)
Disinfection (dr.sumesh)
- 2. CONTENTS INTRODUCTION TERMS & DEFINITIONS FACTORSINFLUENCING PROPERTIES LEVEL OF DISINFECTION DISINFECTION METHOD EFFICACY TESTING
- 3. INTRODCTION •All are are interrelatedterms aiming to destroy or remove microorganism but differ in efficiency. STERILIZATION DISINFECTION SANITIZATION ASEPTIC
- 4. TERMS & DEFINITION STERILIZATION •A process by which all the living microorganisms including viable spores ,are either destroyed or removed from a article, surface or medium SANITIZATION • Refers to the reduction in the pathogenic microbial population to a level, at which the items are considered as safe without protective attires. ASEPTIC • A process where chemical agents called antiseptics are applied on body surface, which kill or inhibit the microorganisms present on the skin.
- 5. DISINFECTION Refer to aprocess that destroy or remove most if not all pathogenic organism but may or may not destroy bacterial spores. European committee Standardisation The section elimination of certain undesirable organism in order to prevent their transmission, achieved by action on their structure or metabolism, irrespective of their functional state. British Standard Institution Destruction of microorganism but not usually bacterial spores. It does not kill all the organism but reduce it to acceptable level for a defined purpose.
- 6. FACTORS INFLUENCING EFFICACY Theefficiency of disinfectants is affected by various factor Organism load Contact time Nature of organism Concentration Temperature Local pH Organic matter Biofilm
- 7. PROPERTIES OF IDEALDISINFECTION Broad microbial activity Fast acting Not affected by organic matter Non-toxic Compactable with the surface Order less or Pleasant order Economical
- 8. TYPES OF DISINFACTANTS HIGH-LEVELDISINFECTANTS (HDL) INTERMEDIATE-LEVEL DISINFECTANTS (IDL) LOW-LEVEL DISINFECTANTS (LLD)
- 9. DISINFECTANTS PHYSICAL METHODCHEMICAL METHOD HLD No physical method • Aldehyde Glutaraldehyde, Ortho-phthalaldehyde, Formaldehyde • Peracetic acid • Hydrogen peroxide ILD • Heat based method:- Pasteurization, Boiling • UV (Non ionizing ) Radiation • Alcohols Ethyl alcohol, Isopropyl alcohol • Phenolics Phenol, Cresol, Lysol • Halogens Iodine, Chlorine LLD No physical method • QAC • Chlorhexidine
- 10. SPECTRUM OF ACTIONOF DISINFECTANTS LEVEL OF DISINFECTANTS BACTERIAL SPORES TB BACILLI NON- ENVELOPED VIRUS FUNGI VEGETATIVE BACTERIA ENVELOPED VIRUS HLD +/- Yes Yes Yes Yes Yes ILD No Yes Yes Yes Yes Yes LLD No No +/- +/- Yes Yes
- 11.
- 12. HDL Capable of killing bacterialspores and all microorganisms when used in sufficient concentration and suitable conditions.
- 13. MOA: They combinewith nucleic acid, proteins and inactivate them by cross linking & alkylating the molecules. Glutaraldehyde Have to be activated before use. Once activated, remains active for 14 days. Used for semi critical equipment, Fogging Cleaning of floor & surfaces of critical areas. Advantage • Active in the presence of organic matter • Non-corrosive to equipment. Disadvantage • Pungent odour • Eye irritation • Contact dermatitis. ALDEHYDE
- 14. Ortho-phtharlaldehyde Advantage • Does notrequire activation, • Better odour • less eye irritation, • acts faster (5-10 min) Disadvantage • Does not kill spores effectively • Stain skin grey. Available in 0.55%, Used for disinfection of semi critical items.
- 15. Formaldehyde • Excellent HLDbut for health care issue it is only restricted to non-patient care. • Used for preservation of anatomical specimen and stool specimen. • Fumigation of closed area done. (obsoleted practice)
- 16. PERACETIC ACID Mostly usein automated machines. 0.1-0.2% Manual immersion 5 -15min instruments sterilization Advantage Combination with hydrogen peroxide used for disinfecting hemodialyzers. Disadvantage Expensive Material compatibility issues Irritation
- 17. HYDROGEN PEROXIDE Works byproducing destructive hydroxyl free radicals that can attack various cell components. •3% •Surface disinfection •Wound cleaning •3-6% •Disinfect soft contact lens, tonometer biprisms, ventilators, fabrics, endoscopes, etc. •>4-5% •Sporicidal •6-7.5% •Plasma sterilization Vaporized from is used for industrial sterilization
- 18. • Active inpresence of organic material • Rapid in action • Nontoxic • Good cleaning ability Advantage • Expensive • Contraindicated for use on copper brass, zinc, aluminium • Chemical irritation • Have to stored in dark containers. Disadvantage
- 19.
- 20. ALCOHOL • Act bydenaturation of proteins MOA • Bactericidal, Fungicidal • 70% used as skin antiseptic Advantage • Not Sporicidal • Inactivated by organic matter • Flammable • Evaporate rapidly Disadvantages
- 21. PHENOLICS Disadvantages Causes hyperbilirubinemia ininfants. Advantages Only ILD which is active in presences of organic matter Use Cresol & Lysol used as disinfectants. 5% phenol is mycobactericidal Chloroxylenol use as antiseptic MOA Phenol / carbolic acid was first introduced as antiseptic and disinfectant for surgery by Joseph Lister. Phenolics act as protoplasmic poison, disrupt the cell wall and precipitate the cell proteins .
- 22.
- 23. Iodine •Iodine acts by disruptionof protein and nucleic acid. Tincture of iodine Iodine (2%) in potassium iodide. Iodophor Iodine + providone
- 24. USE •3% •Topical solution •7.5% •Hand scrub •10% •Skin preparation Also useas disinfectant for medical equipment 1% Mouth wash 1% Oral antiseptic
- 25.
- 26. Hypochlorite All preparations yieldhypochlorous acid which causes oxidation of cellular materials and destruction of vegetative bacteria and fungi. Uses • Large blood spill: 0.5% • Small blood spill: 0.05% • Pre-treatment of liquid waste: 1% • Sporicidal: 0.5% • Laundry items: 0.1% Advantages • Rapid • Non-flammable • Low cost Disadvantages • Inactivated by organic matter • Toxic to skin & mucosa • Carcinogenic • Corrosive • Offensive order
- 27.
- 28. CHLORHEXIDINE GLUCONATE CHG Isa biguanide disinfectant, acts by disruption of cytoplasmic membrane. Uses • Mouthwash (0.1- 0.2%) • Hand rub (0.5%) • Skin disinfectant (2%) • Hand wash (4%) Advantages • Prolonged action than alcohol. • Less irritant. Disadvantages • pH dependent • Reduce in organic matter • Dermatitis on prolonged use. Savlon (Combination of CHG 0.3%, cetrimide & isopropyl alcohol)
- 29. QUATERNARY AMMONIUM COMPOUND Positivelycharged quaternary nitrogen (+) Long hydrophobic aliphatic chain MOA Disruption the cell membrane & denature the proteins. Use Sanitation of noncritical surfaces & medical equipment Example • Benzyl ammonium chloride(does not act in hard water) • Didecyl dimethyl ammonium bromide (Active in hard water)
- 30.
- 31. CLEANING AGENT • PROPERTIES Easilyemulsifiable Saponifiable, Non-toxic Surfactant like action. • TYPES 1) Enzymatic / Photolytic Cleaner 2) Cleaning Chemical / Detergent
- 32. CLEANING METHOD Manual Cleaning Immersionthe instrument or wipe the surface with cleaning agents. Automatic or Mechanical Cleaning Cleans faster with higher standard Hard to reach parts of instrument. Eg:- Ultrasonic washer Washer disinfector Automated cart washer
- 33.
- 34.
- 35.
- 36. DISINFECTION OF ENVIRONMENT ORDER •Cleaning with a cleaning agent is performed first, before applying disinfectant • CDC recommends to use ILD to LLD for environmental disinfection. SEQUENCE • Cleaner to dirtier area • Higher to lower • Inward to outwards
- 37. FREQUENCY OF CLEANINGDEPENDS ON • Probability of contamination • Vulnerability of population to infection • Frequency of hand contact COMMON SITUATIONS • Non-critical surfaces: 2-3 times a day • Mattress: weekly or after discharge • Doors, windows, walls, ceiling: once a month or soiled • High touch area: every 3-4 hours.
- 38.
- 39. DISINFECTION OF OPERATIONTHEATRE Cleaning followed by disinfection by aldehyde based disinfectants FREQUENCY • First cleaning of the day before the case • Between cases(cleaning 3 to 4 feet perimeter around the OT table) • Terminal cleaning of OT after the last case. • Detailed wash-down of the OT complex once a week
- 40. •25ml 40% Formaldehyde heating dish. Sealwith adhesive tape •Vaporize the formaldehyde & leave it over night. •Following day expel the air through HEPA filter •Open the front closer 1cm for increase air flow, when all vapours are removed, remove the seal and check the air flow DISINFECTION OF SAFTY CABINATE
- 41.
- 42.
- 43. RISK CATEGORY DEFINITION RECOMMENDED METHOD MEDICAL EQUIPMENTOR SURFACE Critical Device (High Risk) Items enter in normal sterile site Sterilization Surgical instruments, Implants, Rigid endoscope, Syringes, Needles Semi-Critical Device (Intermediate Risk) Items contact with mucous membrane and body fluid HLD Respiratory equipment, Non-invasive flexible endoscope, Bed pans, Urine bottle Non-Critical Device (Low Risk) Item contact with intact skin ILD or LLD Non-Critical patient item, Non-Critical environment surface
- 44.
- 45.
- 46.
- 47.
- 48.
- 49. PHENOL COEFFICIENT (RIDEALWALKER) TEST Highest dilution of the test disinfectant that kills S. Typhi in a given time Highest dilution of phenol that kills S. Typhi in the same time If >1, the test disinfectant is said to be more effective than phenol DRAWBACKS 1) only the phenolic compounds can be assessed 2) it does not assess the ability of the disinfectant to act in presence of organic matter.
- 50. CHICK MARTIN TEST •It is a modification of Rideal and Walker test • Asses the ability in presence of organic matter CAPACITY (KELSEY-SYKES) TEST • It tests the capacity of a disinfectant to retain its activity when the microbiological load keeps increasing. • Used to test efficacy of new disinfectant (which dilutions are suitable for use)
- 51. IN-USE (KELSEY-MAURER) TEST •It simulates real-time situation. • It is used to determine whether an in-use solution of disinfectant in hospital is microbiologically contaminated.