Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Dr. Abdelmonem Altarhony Infection control measures III Objectives At the end of the course, the students should have an understanding of: • • • • • Sterilization and disinfection : Instruments infection control Surfaces disinfection Instrument Processing Types of sterilization Disinfection and Sterilization • Methods that break the chain of infection or interrupt the infectious disease process: Disinfection The process of destruction of pathogenic microorganisms by direct exposure to chemical and physical agents. Disinfection and Sterilization Antiseptics Chemical disinfectants which can be safely applied to skin or mucous membrane and are used to prevent infection by inhibiting the growth of bacteria. Sterilization The process by which an article, surface or medium is free of all viable microorganisms either in the vegetative or spore state. • Antiseptics: Clorhexidine. Antiseptic • Skin and mucous membranes • Less active against Gram – • Limited virucidal, tuberculoidal and sporicidal activity. Recommended as mouth rinse before clinical procedures. Disinfectants • Activity is reduced by organic debris or blood. • Disinfection can not occur until fresh disinfectant is reapplied to a thoroughly cleaned surface. • Disinfection does not sterilize. Disinfectant • Hypochlorite's • These broad spectrum, inexpensive, fast acting are of choice against viruses such as Hepatitis B and C and HIV viruses. • Not much useful against spores • Bleaching activity • It is recommended for disinfection of counter tops and work surfaces. • Recommended for disinfection of blood spills ( 1:10 dilution ) Phenolic Chloroxylenols (Dettol and Lysol ) •Broad spectrum activity, effective against gram + and – bacteria, fungi and yeast. •They are not effective against non enveloped viruses and spores. Cleaning and disinfection of surfaces. Alcohols- disinfectant and antiseptic • There are two water-soluble alcohol that can be used in disinfection: ethyl alcohol and isopropyl alcohol. • Mode of its action : denaturing bacterial proteins. • Flammable • Bactericidal against Gram + and Gram,tuberculocidal, fungicidal, and virucidal against enveloped viruses (HIV, influenza, herpes viruses). Alcohols- disinfectant and antiseptic • Not effective against bacterial spores and have limited effectiveness against nonenveloped viruses (adenovirus, rotavirus) • Concentration required : 60-90% in water • Higher concentrations are less effective as the action of denaturing proteins is inhibited without the presence of water. Surfaces disinfection • Wipes, sprays and foams typically use less volume of product than solutions do. This reduces exposure to chemicals. Wipes use the least product, are quick to use, and are less likely to cause aerosolization, splatter, or dripping of the product. Iodine Antiseptic • Iodine is rapidly bactericidal, fungicidal, tuberculocidal, virucidal, and sporicidal. 2% iodine in 50% alcohol (tincture), which kills more rapidly and effectively than alcohol alone. Skin disinfection and pre-operative preparation of skin. • Triclosan Broad spectrum antimicrobial It is widely used in handwashing and surgical scrubs > 1 % concentration. Two recent US studies (Fischler et al. 2007, Fuls et al. 2008) demonstrated that hand washing with antimicrobial soap containing triclosan (0.46%) reduced bacterial load and transfer of bacteria from hands, compared to handwashing with a non-antimicrobial soap. Instrument infection control Critical, Semicritical and Noncritical Instruments Proper Techniques and Sequencing of Procedures • Cleaning Prior to Disinfection or Sterilization • Spray enzymatic foam onto non-disposable instruments and trays to start cleaning process. • Remove all debris is the essential first step in proper disinfection or sterilization. • The presence of visible or non-visible debris or organic substances may interfere with disinfection and sterilization. Ultrasonic and sonic vibration: High frequency sound waves beyond the sensitivity of human ears are called as ultrasonic waves. • It is the safest way to clean sharp instruments. Stubbs B. et all, 1992. • They have the property to disrupt the cells but the results have been variable between good and poor if used without periodic testing and maintenance. • Gram negative rods are more sensitive to ultrasonic vibration whereas Gram positive cocci, spores of fungi and bacteria are resistant to the vibration. Packing & Sterilizing Do and Don´t of Instrument Recycling Do the following: • Wear protective puncture-resistant gloves to handle used instruments. • Keep instruments wet in an antibacterial solution before cleaning. • Use an ultrasonic cleaning device. • Use good quality sterilizer equipment. Do and Don´t of Instrument Recycling • Have steriliser annually inspected regarding gaskets, timer, valves, and temperature and pressure gauges. • Place only dry instruments in the sterilizer. • Use a wrap that will be penetrated by the steam or gas used. • Load the sterilizer loosely; leave space between large packs. • Keep a record of daily indicators and weekly spore tests. Don´t do the following • Place wet instruments into any type of sterelizer unless so instructed. • Overwrap cloth packs or use impermeable wraps for steam or chemical vapor pressure sterelization. • Use closed, non perforated trays, foil, canister, or other sealed containers in gas or steam sterelizers. • Overload or cram packs toguether in the sterilizer. • Decrease the required time for sterilization . • Add instruments to a sterilizer without restarting the cycle. Steps in cleaning and disinfecting Step 1 Step 2 • 1. Rinse the article with • 2. Wash the article in hot cold water to remove water and soap. organic materials • Note: the emulsifying • Note: hot water coagulates action of soap reduces the protein of organic surface tension and material and tends to make facilitates the removal of it adhere. E.g. of organic dirt. Washing dislodge the material- pus and blood emulsified dirt Step 3 • 3. Use brush and or bristle to clean the grooves and corners. Scrubbing helps to dislodge foreign materials Step 4 • 4. Rinse the article well with warm water-hot water Step 5 • 5. Dry the article. It is considered clean but not sterile. Step 6 • Clean the brush, gloves and sink. These are considered soiled until they are cleaned appropriately, usually with disinfectant Breaking the chain of infection: Instrument Proce Sterilization 1. Heat sterilization 2. Chemical sterilization 3. Radiation sterilization 1. Heat Sterilization It is the simplest, most effective and inexpensive method. Types of heat sterilization : a)Steam sterilization (Autoclaving) b)Dry heat sterilization Dry-Heat Sterilization Advantages: • It is effective and safe for metal instruments because the process does not dull instrument edges or rust/corrode the instruments. Disadvantages: • Less reliable than autoclaving • Many materials do not tolerate • dry heat (as media) Dry-Heat Sterilization • Heating at atmospheric pressure and often use a fan to obtain uniform temperature by circulation. • Heat at 180º for half hour , 170º for 1 hr., or 160º C for 2 hrs. Temperature (°C) 120 140 150 160 170 180 Time (minutes) 480 180 150 120 60 30 Steam Sterilization (MOIST HEAT ) • Steam appliedd under pressure (1210 C for 15 min) is the most effective method of moist heat sterilization. • The steam must directly contact the materials to be sterilized. • Don´t overload. Steam Sterilization (MOIST HEAT ) Advantages: • good penetration • maintains integrity of liquids (e.g. Lubricants) due to the 100% humidity within the chamber. Disadvantages: • Non stainless steel metal items corrode • may damage plastic and rubber items Chemiclave • Carbon steel and other corrosion-sensitive burs, instruments, and pliers are said to be sterilized without rust or corrosion. • Expensive Cold Sterilization • • • • • Glutaraldehyde 2 to 3 % concentrations Can kill bacterial spores in 6 to 10 hours Broad spectrum action against vegetative microorganisms. Toxic and corrosive It is used to disinfect floors, surgical instruments, plastic equipment, which can not be heat sterilized. • Procedure: • Use for no more than 2 weeks ( lost of activity) Immerse object in liquid for several hours. • Rinse with sterile water after end of procedure. Radiation Sterilization • Provides effective way of sterilization when using non ionizing radiation in high doses (Gamma radiation ). • it is clean process • dry process • the object full exposure from all directions RADIATION Non Ionisizing radiation: Types Produced by Mode of action Uses Low energy UV lamps DNA damage Infrared rays: (Infrared and Sterilization ultraviolet rays) of prepacked items such as syringes . Ultraviolet rays: Used for disinfecting operation theatres Comments Use of UV light is limited by penetration and hazardous. RADIATION Ionisizing radiation: Types Produced by High energy Cobalt-60 ionizing type based (Gamma rays instruments and high Energy electrons such As X-rays and Cosmic rays) Mode of action DNA damage Uses Comments Sterilization They are antibiotics, expensive. hormones They are very and other effective due to prepacked high penetrative disposable power. items such as catheters, gloves, syringes, infusion sets, oils, animal feeds, etc. In summary • Sterilization and disinfection are costly and time consuming process • However, it is an essential in all health care facilities to avoid infection. • It depends the material and users of instrument. • Staff should keep in mind that contaminated instrument present risk to the sample as well as the user himself. Thank you