Sterilization of ot & ot equipments pritam


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Sterilization of ot & ot equipments pritam

  2. 2. DEFINITIONS<br />Antiseptic Substance that has antimicrobial activity & that can be safely applied to living tissues.<br />Bacteriostatic Agent which prevents bacterial growth but doesn’t kill bacteria.<br />Bioburden The number & types of viable organisms with which an object is contaminated.<br />
  3. 3. Biological Indicator It is sterilization process monitoring device consisting of a standardized viable population of micro-organisms of high resistance to mode of sterilization being monitored.<br />Chemical Indicator It is sterilization process monitoring device designed to respond with a characteristic chemical change to one or more parameters of sterilization cycle.<br />
  4. 4. Chemosterilizers  A chemical used for destroying all forms of microbiological life including spores.<br />Decontamination The process by which contaminated items are rendered safe for personnel without protective attire to handle or render item safe for reuse. <br />
  5. 5. Disinfection  Destruction of many but not all micro-organisms on inanimate objects. <br />The Center Of Disease Control & Prevention (CDC) has given 3 levels of disinfection<br />
  6. 6. Disinfectants chemical germicides formulated to be used on inanimate objects. <br /> The Environmental Protection Agency (EPA) classified them as those <br /><ul><li>With Tuberculocidal activity
  7. 7. Without Tuberculocidal activity.</li></ul>Mechanical Indicators  sterilizer components that gauge & record time, temperature, humidity pressure during sterilizing cycle.<br />
  8. 8. Sterilization  destruction of all form of micro-organisms ( high temperature).<br />Terminal sterilization sterilization process carried out after final packaging of the item.<br />Sterility Assurance Level (SAL) the probability of survival of micro-organisms after a terminal sterilization process & is predictor of efficacy of the process. A SAL of 10-6 indicates non sterile item.<br />
  9. 9. ORDER OF RESISTANCE<br />In descending order are-<br />Prions<br /> Coccidia (cryptosporodium)<br /> Bacterial spores (bacillus)<br /> Mycobacterium<br /> Cysts<br /> Small non-enveloped viruses (Polio)<br />
  10. 10. Trophozites<br /> Gram Negative Bacteria (Pseudomonas)<br /> Fungi<br /> Large non-enveloped viruses (adenovirus)<br /> Vegetative Bacteria (Staph Aureus)<br /> Lipid or medium sized viruses (HIV, Hepatitis B)<br />
  11. 11. STAGES IN THE PROCESS ARE<br />General Cleaning & Decontamination. <br />Then if required<br />Sterilization<br />Disinfection<br />
  12. 12. CLEANING OF EQUIPMENTS<br />Aim<br /> To remove retained salt & organic soil which can inactivate chemical germicides or protect organisms from destruction during disinfection.<br />Procedure<br />Immersible items should be cleaned under water, with or without detergent for atleast 3 min. to prevent aerosolization of organisms & those not immersible can be cleaned with cloth soaked in detergent & water.<br />
  13. 13. Disassembly-<br />Devices should be disassembeled & jointed instruments must be opened.<br /> <br />Cleaning-<br />Before cleaning, manufacturer`s instruction are consulted.<br />Tapes, soils, adhesive residues are dissolved by using appropriate solvents.<br />
  14. 14. Devices must be soaked in protein dissolving solution to prevent coagulation of blood & then it should be scrubbed thoroughly inside out.<br />Complicated devices can be cleaned by ultrasonic cleaning after gross soil has been removed.<br />
  15. 15. Rinsing- <br />After cleaning, rinsing should be performed; lumens & channels are well flushed during each rinse. They should be towel or air dried.<br />
  16. 16. METHODS OF STERILIZATION<br />PASTEURIZATION<br />It’s a high level disinfectant.<br />The equipment is immersed in water at an elevated temperature of usually 80°c for 10min or 70°c for 30min.<br />It can`t kill all spores & viruses. So it is recommended for perishable & where absolute sterility is not required.<br />E.g. Breathing tubes, ETT, Reservoir bags, Face masks, Laryngoscope blades, ventilator bellows & any rubber goods.<br />
  17. 17. Precaution <br />Care must be taking regarding time.<br />Addition of extra items in the middle of process should not be done.<br />Advantages <br />It is simple, inexpensive & reliable.<br />Doesn’t emit toxic fumes<br />It is less damaging to instruments as low temperature is required.<br />
  18. 18. Disadvantages<br />Items will be wet & must be dried.<br />Prepackaging is not possible.<br />Plastic & rubber articles loose there shape & antistatic properties because of repeated exposure to high temperatures.<br />
  19. 19.
  20. 20. BOILING<br />For small articles like face masks.<br />It is suitable for metal & also for rubber & neoprene items. <br />Instruments are boiled in water for 5-15min for destruction of vegetative matter.<br /> <br />
  21. 21. FILTRATION<br />Microfilters are used to prevent entry of micro-organisms<br />They remove particles of diameter 0.5µ or greater<br />
  22. 22. STEAM STERILIZATION (AUTOCLAVING)<br /><ul><li> Here saturated steam under pressure is used.</li></li></ul><li>Parts <br />Chamber (pressure vessel)–It is the portion of sterilizer in which the materials are placed & through which steam is circulated.<br />Jacket- It is the portion surrounding the Chamber. It functions to maintain the temperature of chamber.<br />The equipments are first cleaned & the packaged in muslin, linen or paper which are easily penetrated by steam & then placed on shelf in the chamber<br />
  23. 23. Phases <br />Conditioning/Heat Up Phase<br />Air, if present, should be evacuated before sterilization, from the chamber as it reduces the amount of steam entering the Autoclave & hence the temperature achieved.<br />Exposure/Sterilization phase<br />As the steam enters the load, it gives Latent Heat to materials rapidly on contact.<br />Microbial destruction will be most effective at these locations.<br />Once intended temperature is reached, sterilization time is set.<br />
  24. 24. Principle <br />Water boils when its vapor pressure equals that of surrounding atmosphere. <br />Thus when water is boiled in closed vessel at increased pressure, the temperature at which it boils & that of steam which is formed will exceed 100°C. <br />
  25. 25. When steam comes in contact with cooler surface  condenses to water & gives up its latent heat to that surface.<br />Thus 1600ml of steam at 100°C & at atmospheric pressure condenses into 1ml of water at 100°C & releases 518calories of heat.<br />
  26. 26.
  27. 27. It can also be carried out at Low Temperature & Low Pressure (LTS) i.e. at 37kPa with 74°C, but it won’t kill spores.<br />The addition of vapor of formaldehyde to this is called as low pressure steam & formaldehyde (LTSF) which can kill many if not all spores.<br />Ordinarily rubber goods, linens & metals are autoclaved.<br />Post exposure/ Exhaust Phase.<br />At the end the steam should be exhausted from the autoclave to avoid condensation of water on the load when cool air is admitted.<br />
  28. 28. Flash Sterilization <br />Refers to steam sterilization of items for immediate use.<br />
  29. 29. Characteristics of Steam<br />It should be optimum, otherwise efficacy will be decreased.<br />It should be free from air, liquid or solid particles.<br />For this, filters can be installed in the upstream of streamline.<br />
  30. 30. Problems <br />Problems with the Steam<br />Steam quality should be greater than 97%.<br />Water, if present, results in wet steam.<br />If the pressure is too high, it will cause the steam to rain & packs will become wet. <br />If the pressure is too low, the steam will be superheated which is less able to transfer heat to items & it will be difficult to attain uniform temperature<br />
  31. 31. Air in Autoclave Chamber<br />Air in the chamber will impair sterilization as it is poor conductor of heat & retards the penetration of steam.<br />Efficacy of air removal process can be tested by Bowie-Dick test.<br />
  32. 32. Equipment Malfunction<br />Equipment malfunctions like out-of-calibration temperature or pressure gauges, leaks, maladjusted control valves etc.<br />Personnel Errors<br />Personnel errors like inadequate cleaning, packaging methods, poor loading techniques etc.<br />
  33. 33.
  34. 34. Monitoring<br />Mechanical Monitors: <br />Devices that record time, temperature & pressure.<br />Biological Indicators:<br />they are standardized preparation of spores.<br />A positive biological indicator is indicative of possible sterilization process failure.<br />They should be used atleast once a week but time needed for incubation is long.<br />E.g. spores of Bacillus Sterothermophilus.<br />
  35. 35. Chemical Indicators: these are more practical means & detect problems immediately. <br />The CDC & all major U.S organizations standards & guidelines advocate that a chemical indicator be attached to every package that goes through a sterilization cycle & within each package to be sterilized in what is expected to be the most difficult-to-sterilize location. <br />These are divided into 6 classes, higher the class, more sensitive the indicator.<br />
  36. 36. Class 1- <br />These are Internal & External Process Indicator<br /> These inform that item has been exposed to sterilization process.<br />E.g. External Process Indicator – Autoclave Tape.<br />
  37. 37. Class 2-<br /><ul><li>E.g. Bowie-Dick test for vacuum steam sterilizer.
  38. 38. They only access Vacuum Pump efficiency & detect the presence of air leaks &/or gases in steam.</li></li></ul><li>Class 3-<br /><ul><li>E.g. Temperature Tube.
  39. 39. Contains chemicals that melts & sometimes changes color when the appropriate temp is attained.</li></ul>Class 4-<br /><ul><li>Respond to one or more sterilization parameters.
  40. 40. Contains Ink that changes color when exposed to correct combination of sterilization parameters.</li></li></ul><li>Class 5-<br /><ul><li>Known as Integrating Indicators or Integrators
  41. 41. Respond to all parameters of sterilization over a specified range of temperatures.</li></ul>Class 6-<br /><ul><li>These are emulating indicators.
  42. 42. These are designed to react to all critical parameters over a specified range of sterilization cycles for which the stated values are based on the settings of the selected sterilization cycles</li></li></ul><li>Advantages<br />Can kill all bacteria, spores & viruses.<br />Rapid sterilization. <br />Ease of use.<br />Good penetration<br />Economical.<br />Absence of toxic products/ residues.<br />Materials can be prepackaged & kept sterile until use.<br />
  43. 43. Disadvantages <br />Heat sensitive materials are damaged like plastic & rubber goods.<br />Cause blunting of cutting edges, crossing of metal surfaces.<br />Oil, grease, powders are not sterilized because of lack of penetration.<br />Shortened life of electronic components.<br />
  44. 44. DRY HEATING<br />
  45. 45. Articles are packed in special craft papers and then placed in a thermostatically controlled Dry Heat Sterilizer.<br />Precaution temperature is raised and lowered slowly to prevent breakage by uneven expansion.<br />Mainly suitable for ophthalmic instruments and glass items but not plastics or rubber.<br />It is useful for sterilization of powders, grease, oil and glass syringes.<br />
  46. 46.
  47. 47.
  48. 48. CHEMICAL (COLD) STERILIZATION<br />Utilizes liquid chemical agents<br />Especially useful for heat sensitive equipment.<br />Performed by soaking item in the solution.<br />Kill the organisms by coagulation / alkylation of proteins and also by enzymatic degradation and lysis of cell membranes.<br />
  49. 49. The criteria to be satisfied in the Chemical Methods are<br />Must be capable of killing spores.<br />Should be non-corrosive<br />Should be Non-irritant.<br />Should be Economical.<br />Should be stable<br />Should penetrate grease & fibers.<br />Should be non-toxic.<br />
  50. 50. Factors Influencing Chemical Sterilization:<br />Concentration of the Chemical: <br />Rate of kill of bacteria varies directly with the concentration of the disinfectant.<br />b) Temperature: <br />Designed to be used at room temperature.<br />
  51. 51. c) Evaporation and light deactivation: <br />Volatile agents evaporate easily. Exp: Chlorine Products. Exposure to light adversely affects the disinfectant.<br />d) PH:<br />Alcohols work best in alkaline PH while aldehydes work best in acidic PH.<br />e) Bioburden:<br />The effectiveness of the disinfectant depends on the nature and number of contaminating microorganisms<br />
  52. 52. f) Characteristics of the item to be sterilized:<br />A disinfectant solution will be effective only if it can contact all the surfaces on the item. <br />g)Time: <br />Time required for different chemical agents to function effectively varies from seconds to hours.<br />h) Use Pattern, Use Life & Storage Life: <br />Use Pattern refers to how many times the solution can be used.<br />Use Life indicates limited period of time during which activated solution can be used.<br />Storage life is the time period after which the unused or inactivated product is no longer deemed effective.<br />
  53. 53. FORMALDEHYDE:<br />Used principally in water based solution called formalin. Vapor can be generated from paraformaldehyde tablets which contain 95% formaldehyde in a polymerized form.<br />It is a high level disinfectant.<br />It is non corrosive and is not inactivated by organic matter.<br />Widely used for sterilization of endoscopic equipment, catheters etc.<br />
  54. 54. For better effect it needs relative humidity of 60-80% and temperature of 37°C. <br />Residual formaldehyde may affect the skin, but it can be neutralized by ammonia.<br />Limited by its pungent odor and fumes.<br />Should be handled as a potent sensitizer and probable carcinogen.<br />
  55. 55. QUATERNARY AMMONIUM COMPOUNDS (QUATS)<br />Low level disinfectants<br />They are bactericidal, fungicidal & viricidal but not sporicidal.<br />They are effective against gram positive than gram negative and marginally effective against Pseudomonas. They inactivate HIV but not hepatitis virus.<br />They are inactivated by organic materials.<br />Side effects are allergic reactions and contact dermatitis. <br />
  56. 56. PHENOLIC COMPOUNDS<br />They are intermediate to low level disinfectants.<br />Derived from carbolic acid (phenol), one of the oldest germicides.<br />They are bactericidal, fungicidal and viricidal but not sporicidal.<br />They are active in the presence of organic matter.<br />They are irritant to skin & mucous membranes, have bad odour.<br />They are absorbed by rubber and residual disinfectant may cause tissue irritation.<br />
  57. 57. ALCOHOL<br />Intermediate level disinfectants.<br />Ethyl alcohol is bactericidal in 60-90% concentration and isopropyl alcohol in 60% concentration. <br />They kill bacteria but not spores, action against viruses is variable.<br />CDC recommends exposure to 70% ethanol for 15mins to inactivate the hepatitis virus but 1 min for HIV.<br />Their effectiveness is limited because of rapid evaporation, lack of ability to penetrate organic matter.<br />
  58. 58. They are used mainly to disinfect external surfaces of equipment like stethoscopes, ventilators, fiberoptic cables.<br />They can damage mounting of lensed instruments and tend to swell and harden rubber.<br />
  59. 59. Chlorhexidine (Savlon) : <br />It is a non detergent chemical disinfectant usually used in the concentration of 0.5% in 70% alcohol for skin.<br />Tubes, masks etc. are sterilized by keeping for 20 min in 0.1% aqueous solution.<br />Chloroxylenol (Dettol): <br />It is used as mild antiseptic agent<br />
  60. 60. IODOPHORS<br />It is a combination of iodine and carrier with a resulting complex providing sustained release reservoir of iodine.<br />They are bactericidal, viricidal and tuberculocidal but not sporicidal.<br />These are intermediate to low level disinfectants.<br />They corrode the metallic items and non-metallic items may be stained or discolored.<br />
  61. 61. PERACETIC (PEROXYACETIC) ACID<br />It is acetic acid with an extra oxygen atom.<br />It is bacteriocidal, sporicidal, fungicidal and viricidal.<br />They are effective in the presence of organic matter. But it is corrosive and irritating to skin in concentrated solution.<br />It is active ingredient in the steris sterilant. This is a single use concentrate of 35% peracetic acid + corrosion and degradation inhibitors.<br />
  62. 62. Used in wide variety of heat sensitive and delicate instruments.<br />Used on wet or dry items and there is no personnel exposure. It can be situated in the Operating room suite.<br />It is useful only for totally immercible objects and only small number instruments can be processed in a cycle.<br />
  63. 63. CHLORINE AND CHLORINE PRODUCTS<br />They are intermediate level disinfectants.<br />They are active against bacteria and viruses but not spores.<br />They are available both in liquid (sodium hypochlorite) and solid (Calcium hypochlorite) forms.<br />They are most widely used, inexpensive and fast acting.<br />
  64. 64. Highly effective against HIV.<br />Household bleach is an inexpensive and excellent source of sodium hypochlorite.<br />A 1:100 to 1:1000 dilution is effective against HIV. <br />1:5 to 1:10 dilution is effective against hepatitis.<br />It also inactivates CruetzFeldtJakob disease with an exposuretime of 1 hr. <br />
  65. 65. Their use is limited by their corrosiveness, inactivation by organic matter and may leave residue which causes irritation to skin, eye and respiratory tract<br />Potential hazard is the production of carcinogen bis-chloromethyl ether, when hypochlorite solutions come into contact with formaldehyde. <br />A mixture of hypochlorite with acid will cause rapid evolution of toxic chlorine gas. <br />
  66. 66. Hydrogen peroxide<br />It is an effective bactericidal, fungicidal, viricidal and sporicidal.<br />It is commercially available as 3% solution but can be used upto 25% concentration.<br />It is non corrosive and not inactivated by organic matter but irritant to skin and eyes.<br />
  67. 67. Glutaraldehyde (cidex)<br />It is a saturated dialdehyde. It is used in 1.0% concentration (but highly effective in 2% concentration).<br />It is high level disinfectant. It kills spores within 12 hrs and viruses within 10 min.<br />Widely used because of their excellent biocidal properties, activity in the presence of organic matter, non corrosiveness and noncoagulation of proteinaceous material. <br />
  68. 68. Disadvantages :<br />It is noxious and irritating to tissues and hence thorough rinsing of all exposed materials is mandatory.<br />Prepackaging is not possible and equipment will be wet.<br />Pseudo-membranous laryngitis has been linked to disinfection of tracheal tubes with glutaraldehyde.<br />
  69. 69. Ozone:<br />Sterilizers use O2, water & electricity to produce Ozone.<br />Advantages:<br />Useful for most goods that need low temperature sterilization.<br />Process is environmentally friendly.<br />Treated objects are dry.<br />Disadvantages:<br />Not approved for flexible scopes & reactive materials such as copper & brass.<br />Unsuitable for natural gum rubber products<br />
  70. 70. Advantages of Chemical Sterilization<br />Technically easier.<br />Suitable for equipments damaged by heat sterilization.<br />Sophisticated chemical methods like Ethylene Oxide achieve perfect sterilization.<br />Disadvantages:<br />Act only on exposed surfaces<br />Some chemicals react with metals.<br />Some impregnate with the materials such as rubber & plastics & some agents destroy it.<br />Residual chemicals may form the source of infection.<br />
  71. 71.
  72. 72. Gas sterilization<br />EO is used for this purpose.<br />It is a liquid below 11°C.<br />It is available in high pressure tanks, unit dose ampoules and cartridges. <br />
  73. 73. 1. Preparation for ethylene oxide (EO) sterilization (propylene oxide): <br />Before packaging, items must be disassembled, cleaned and dried to allow the gas to penetrate throughout the whole product.<br />Caps, plugs, valves, stylets must be removed. Hollow bore products and needles should be open at both ends.<br />They should be towel or air dried. <br />
  74. 74. A relative humidity of 35% to 70% and a temperature of 18 to 22°C are recommended.<br />Items to be sterilized are placed in carries that do not absorb E.O. They should be loaded loosely to allow for uniform penetration of gas throughout the load.<br />
  75. 75. Factors affecting EO Sterilization :<br />Gas concentration: The solubility of EO in the product and the gas diffusion rate through the product will influence the sterilant concentration.<br />Temperature: Exposure time can be decreased by increasing the temperature. <br />Humidity: Moisture hydrates microbes, making then susceptible to destruction by EO.<br />
  76. 76. Protective barriers: Blood and other proteinaceous materials can act as barriers to EO. <br />Packaging: The wrapping must be permeable to EO gas and water vapor and allow for proper aeration.<br />Exposure time: Depends on factors mentioned above, generally range from 1.5 to 6 hrs. or many require upto 12 hrs<br />
  77. 77. 3. Sterilizers:<br />EO sterilizers are of two types, <br /><ul><li>general purpose and
  78. 78. special purpose. </li></li></ul><li>4. Indicators:<br />Physical, chemical or biological indicators can be used but combination is better. <br />CDC recommends the use of biological indicators at least once a weak.<br />
  79. 79. 5. Aeration:<br />EO not only comes in contact with all surfaces of articles being sterilized but also penetrates some items, which then retain varying amounts. <br />Aeration may be done passively in air i.e ambient aeration or actively in a mechanical aerator.<br />
  80. 80. Factors affecting aeration:<br />Metal and glass items do not absorb EO and require little or no aeration.<br />Plastics, rubber, cloth, paper and muslin may absorb significant quantities. <br />The most common material retaining large amounts of EO is PVC. Rubber absorbs little, polyethylene and nylon absorb still less.<br />Diluent, gas mixtures with a fluorocarbon require longer aeration time than those diluted with C02.<br />
  81. 81. 6. Complications of EO sterilization :<br />Patient complications skin reactions, laryngotracheal inflammation, anaphylaxis, when blood comes in contact with EO sterilized items, destruction of red cells can occur.<br />These are mainly due to by products <br />Ethylene Glycol -formed by the reaction of EO and water.<br />Ethylene Chlorhydrin- formed when EO comes in contact with chloride ions that may be present in previously γ-irradiated PVC items.<br />
  82. 82. Personnel complications:<br /> Acute exposure may cause URTI, eye irritation, headache, blunting of taste and smell, coughing.<br />With higher concentrations nausea, vomiting diarrhoea, fatigability, memory loss, drowsiness, incoordination, shortness of breath, convulsions have been reported. <br />Respiratory paralysis and peripheral nerve damage may be delayed for 6 hrs or more after exposure.<br />Chronic exposure can cause corneal burns, cataracts, epithelial keratitis, sensorimotor polyneuropathy, anemia. <br />EO may be mutagenic or carcinogenic.<br />
  83. 83. Advantages:<br />It is effective against all organisms:<br />Damage to most equipment is minimal.<br />Items can be prepackaged.<br />Used for sterilization of delicate instruments like pump oxygenators, valves, ventilators etc.<br />Disadvantages:<br />More expensive<br />Fire and explosions have been reported.<br />Long duration.<br />Personnel need to be highly trained and supervised. <br />
  84. 84. RADIATION STERILIZATION<br />Mainly used for disposable products.<br />Gamma radiation is an electromagnetic wave produced during the disintegration of certain radioactive elements like cobalt-60.<br />All organisms including spores, viruses will be killed. Lethal dose is 2.5 megarads(kills bacteria by ionizing there DNA).<br />The products can be prepackaged.<br />
  85. 85. As there is no temperature rise, thermolabile materials can be sterilized.<br />Equipments may be used immediately after treatment, with no risk from retained radioactivity.<br />Disadvantage is that it is not practical for every day use and it is expensive.<br />
  86. 86. GAS PLASMA STERILIZATION<br />It uses a gaseous chemical germicide (peracetic acid, hydrogen peroxide) and gaseous plasma. <br />
  87. 87. Advantages <br />It is an effective sterilant for a variety of medical devices.<br />It offers rapid low-temperature sterilization.<br />Does not have environmental problems associated with EO. <br />No personnel protection equipment are needed.<br />
  88. 88. INFRARED RADIATION<br />This is method of sterilization by dry heat usually used to sterilize the syringes and small instruments<br />
  89. 89. ULTRAVIOLET RADIATION<br />It is done by submitting the whole operation area to the light but the staff has to be protected from sun burn<br />
  90. 90. STERRAD SYSTEM<br />In this system, hydrogen peroxide is the precursor of active species of plasma.<br />Total processing time is about 1 hr.<br />It can be used for most items with exception of celluloric materials e.g. cotton, powders, liquid and devices containing dead end lumens.<br />It is well suited to heat and moisture sensitive instruments since temperature does not exceed 50°C and sterilization occurs in low moisture environments.<br />
  91. 91. Advantages-<br />These are small capacity systems.<br />No venting or special installation is required.<br />The process requires no aeration and<br />There are no toxic residues<br />
  92. 92. PLASMALYTE SYSTEM<br />In this system the gas plasma is produced in a separate plasma chamber where the gas mixture of H2, O2 and Argon is exposed to microwave electromagnetic field.<br />Sterilization is carried out at / below 55°C.<br />The duration of entire cycle varies from 3/2 to 4 hrs.<br />It can be used for any item, but not recommended for liquids, powders, flexible endoscopes. <br />
  93. 93. CDC rationale for Cleaning, Disinfection and Sterilization<br />CDC has published guidelines on how to prevent or control specific nosocomial infection problems. <br />They have divided items into three categories, based on the potential risk of infection involved in their use. <br />
  94. 94. Critical items :<br />Are those that penetrate the skin and mucous membranes or are in contact with normally sterile areas of the body. <br />These include vascular needles and catheters and regional block needles. <br />
  95. 95. 2) Semicritical items: <br />These are the items that come in contact with intact mucous membranes but do not ordinarily penetrate body surfaces.<br />Sterilization is desirable, if not possible, a high levels of decontamination is acceptable.<br />Ex : Endoscopes, laryngoscope blades, temperature probes, facemasks, airways, resuscitation bags, breathing lubes and connectors. ETT, double lumen tubes.<br />
  96. 96. 3) Non critical items:<br />Are those that do not ordinarily touch the patient or only touch the skin intact. <br />Since intact skin normally acts as an effective barrier to most organisms, these items need only intermediate to low level of disinfection.<br />E.g. Cables, CO2 absorber, assemblies, exterior of anaesthesia machine, ventilators, humidifiers, monitors etc. <br />
  98. 98. Anaesthesia Carts & Machines<br />Top surface should be cleaned of visible material between cases.<br />Disinfected with germicide at end of day<br />
  99. 99. Gas Cylinders<br />Washed with water & detergent. <br />Then wiped or sprayed with germicide<br />
  100. 100. Unidirectional valves, APL valves & Water Traps<br />Cleaned & disinfected periodically.<br />They are disassembled & cleaned by wiping disc. The inside of the plastic dome & the valve seat with alcohol or detergent.<br />Some APL valves may be autoclaved & some may be Pasteurized. <br />
  101. 101. Tracheal tubes, Suction Catheters, Airways<br />Washed with soap & water & rinsed.<br />A malleable brush may be used to clean the inner aspect of tubes & airways.<br />Boiling will sterilize it but tubes will be softened.<br />Chlorhexidine 0.1% solution can be used. Here equipments should be soaked for 30-60min for complete sterilization.<br />Autoclaving will be effective. But ETT should be replaced after 6 uses.<br />Gamma radiation is satisfactory.<br />
  102. 102. Face masks<br />Rinsed, soaked & scrubbed after use.<br />Wash with soap & water & thoroughly dried.<br />Keep in water at 60-70°C for 20min. this reduces number of pathogens to very small no.<br />Gas sterilization is v.effective method.<br />It should not be boiled as boiling deteriorates masks<br />
  103. 103. Laryngoscope Blades<br />Boiled or Autoclaved after cleaning, but they may spoil electric connections.<br />Carbolic acid 1-20% for 30min. can be used.<br />Formalin oven can be used.<br />Wiping with 70% alcohol or 0.1% Chlorhexidine in 70%alcohol is useful.<br />
  104. 104. Breathing tubes & Reservoir bags<br />Wash thoroughly, rinse & allow it to dry in air.<br />Repeated boiling spoils the antistatic properties, so it can be boiled once a week for 10min.<br />Can be Pasteurized at 75°C for 10min.<br />Chemical disinfection with glutaraldehyde for 1hr can be carried out by using automatic washing machine or by immersion. Tube should be inserted vertically during procedure<br />
  105. 105. Y-piece<br />Chemical disinfection.<br />Ethylene oxide or Plasma sterilization can be used.<br />It can be soaked in solution of water & detergent, then scrubbed manually or placed in washing machine.<br />
  106. 106. Mapleson System<br />Should be disassembled & component cleaned<br />Metal components can undergo Autoclaving.<br />Rubber & Plastic parts can undergo Gas or Plasma Sterilization. <br />
  107. 107. Adaptors<br />Rinsed & soaked in solution of detergent & water.<br />May be washed manually or in washing machine.<br />Rubber & plastic adaptors- sterilized with EO, plasma sterilization or in Glutaraldehyde.<br />Metal adaptors may be autoclaved or Pasteurized.<br />
  108. 108. Water`s canister<br />Can be washed & boiled.<br />Can be Steam Autoclaved.<br />Can be sterilized using Ethylene Oxide.<br />
  109. 109. Circle Absorber<br />Gamma radiation<br />Ethylene oxide.<br />Formalin chamber.<br />Can be dismantled & disinfected with spirit.<br />Entry of organisms, while in use, can be prevented by using filters. <br />
  110. 110. Ventilators<br />Bacterial filters<br />Ethylene oxide<br />Internal irrigation with antiseptics, provided the circuit is water tight.<br />Ultrasonic nebulization with alcohol, hydrogen peroxide.<br />Some have breathing units which can be autoclaved.<br />Formalin Chambers can be used.<br />
  111. 111. Humidifiers<br />Pasteurized at 60°C. copper sponges may be used during this process as it has antibacterial effect.<br />Frequent & thorough washing may be effective<br />
  112. 112. Syringes & needles<br />Disposable syringes & needles are ideally gamma irradiated.<br />Glass syringes are ideally autoclaved.<br />In case of emergency, boiled in distilled water for 5min.<br />
  113. 113. Instruments for local blocks<br />Lignocaine & Bupivacaine syringes, ampoules can stand Autoclaving at 160°C for 20min at 20psi.<br />Repeated Autoclaving is avoided.<br />Adrenaline ampoules should be autoclaved only once.<br />Disposable sets are gamma irradiated.<br />
  114. 114. Blood pressure cuffs, Tubing's & Stethoscopes<br />Washed & dried thoroughly.<br />Then subjected to chemical disinfection or Gas Sterilization.<br />Nonfabric cuffs – plasma Sterilization is used.<br />Stethoscopes can be washed with water & wiped with alcohol.<br />
  115. 115. Pulse oximeter probes & cables<br />Cleaned by wiping with alcohol.<br />Cables – Plasma sterilization<br />
  116. 116. SPECIAL CONCERNS<br />
  117. 117. Special concern in open case of Pulmonary Tuberculosis.<br />Endotracheal tubes & suction catheters are disposed off.<br />If it is to be reused then keep in 0.1%Chlorhexidine solution for 1hr, then it is cleaned & scraped with soap & water & then sterilized by boiling or autoclaving.<br />Boiling for 3min will kill tubercle bacilli.<br />It can also be immersed in 2%Glutaraldehyde solution for 1hr.<br />
  118. 118. Special concern in Hepatitis B positive cases<br />The virus is killed by Autoclaving & Gamma Radiation.<br />Chemical sterilization- Sodium Hypochlorite 50ppm, <br />Glutaraldehyde 2% for 10 min.<br />Iodophor 80ppm<br />Isopropyl alcohol 70% for 15 min.<br />
  119. 119. Special concern in HIV cases<br />The virus is relatively unstable in environment & can easily be inactivated by wide range of Chemical Disinfectants like-<br />Glutaraldehyde 2% for 10 min.<br />Sodium Hypochlorite 50ppm.<br />Hydrogen peroxide 0.3%.<br />Ethyl alcohol 50%, Isopropyl alcohol 70% for 1 min.<br />Phenol.<br />
  120. 120. Special concern in Prion Diseases<br />It is extremely resistant to normal Sterilization methods.<br />For Critical Devices – Steam Sterilization for 30min at 132°C is recommended.<br />For Non-Critical Devices- Sodium Hypochlorite, undiluted or 1:10 dilution is used. 1N sodium hydroxide at room temperature for 15min can also be used. <br />
  121. 121. Operation theatre cleaning and fumigation<br />
  122. 122. Cleaning programme should be simple and clearly laid out policy which can be adhered to. <br />Daily cleaning should be carried out after the operating sessions are over.<br />All the surfaces should be cleaned with detergent and water and may be wiped over with a phenol if any spills with blood / body fluid are present.<br />All the walls must be wiped down to hand height everyday. <br />
  123. 123. The floors should be scrubbed with warm water and detergent and dried. No disinfectant is necessary. <br />The O.T. table and other non clinical equipments must be wiped to remove all visible dirt and left to dry.<br />Weakly cleaning of all the areas inside the operating theatre complex should be done thoroughly with warm water and detergent and dried. <br />The storage shelves must be emptied and wiped over, allowed to dry and restacked. <br />
  124. 124. Procedure for fumigation:<br />The windows should be sealed and formaldehyde should be generated either by boiling a solution of formalin 40% or by adding it to potassium permanganate, in a metal vessel on the floor, since heat is also generated. The door is than closed and scaled.<br />For a 10 x 10 x 10 ft room - 150 gm potassium permanganate and 280 ml of formalin are used<br />
  125. 125. Duration:<br />In case of any construction in O.T.  48 hrs<br />In case of inflected cases  24hr<br />For routine clean cases  12 hrs.<br />Alternatively 250 ml of formalin and 3000 ml of tap water are put into a machine (auto mist) and time is set for 2 hrs. The mist is circulated for 2hrs inside the closed room.<br />
  126. 126. Room is kept sealed for another 2 hrs for action of vapor. Ventilate for suitable time for vapor to dissipate. Room then can be used.<br />Three swabs are taken from walls, all equipments, floor or O.T. table at intervals.<br />1st swab - 48 hrs after fumigation<br />2nd swab- 24 hrs after Is' swab<br />3rd swab - 12 hrs after 2"d swab<br />
  127. 127. All three consecutive swabs should come negative. <br />In some centres, Bacillocid is being used for fumigation. It is combination of chemically bound formaldehyde and glutaraldehyde. <br />Ideally all O.T. rooms should be fumigated once a week<br />
  128. 128.
  129. 129.
  130. 130. REFERENCES<br />Understanding Anesthesia Equipments- Dorsch & Dorsch.<br />Anaesthesia Equipments- Wards.<br />ISACON 2006, 2007.<br />Textbook Of Anaesthesiology- SathishDeshpande<br />