Steam Sterilizers PDF

Steam Sterilization Tabletop sterilizers Often used in clinics and dental offices. Gravity Displacement Steam This type of sterilizer has no assisted air removal and Sterilizers is dependent on gravity, so steam penetration is slow...

Steam Sterilization Tabletop sterilizers Often used in clinics and dental offices. Gravity Displacement Steam This type of sterilizer has no assisted air removal and Sterilizers is dependent on gravity, so steam penetration is slow and cannot be assured. Cycle times are much longer for this type of sterilizer and load selection is critical. They are not suitable for wrapped items or items with channels (lumens) as they trap air and prevent correct temperatures from being attained. Gravity displacement steam sterilizers may be used for solid metal items such as non-complex surgical instruments. Porous Load (Vacuum Porous load sterilizers incorporate a vacuum-assisted Assisted) Steam Sterilizers air removal stage prior to steam admission and they require a consistent supply of suitable quality steam. A typical cycle consists of: - Conditioning: steam enters the sterilizer chamber and air exits the chamber through the drain. - Exposure: sterilization of the load occurs at predetermined sterilization parameters (time and temperature). - Exhaust: the steam is removed and filtered air is introduced gradually to the chamber. - Drying: it starts at the end of the exhausting phase. The drying time depends on the device, packaging and the sterilizer’s IFU. Immediate use steam a common term that describes the practice of fast sterilization (IUSS) or flash sterilization of surgical instruments at the point of sterilization use, often associated with dropped instruments. Flash sterilization is for non-porous and/or non- hollow surgical instruments in an unwrapped condition. These gravity-type steam instrument sterilizers are usually located in the operating room, in order to process instruments for extremely urgent use, for example a dropped instrument when no alternative is available. These sterilizers operate at 134°C for 3–10 minutes, resulting in wet and very hot medical devices in the operating room environment.  Low temperature sterilizers: Ethylene Oxide (EO) These sterilizers operate at 37 °C or 55°C so are suitable for heat sensitive items. They are used commercially and in some hospitals but are banned in hospital settings in many countries due to the costly health and safety requirements for operating and housing these machines. The EO process works well for heat sensitive equipment such as invasive flexible endoscopes, and cardiac and ophthalmic devices, but requires very long cycle durations to allow of adequate aeration. A typical cycle consists of: Load pre-conditioning—vacuum and humidification Sterilizing gas exposure Gas exhaust and air purge Gas Plasma This method is also suitable for heatsensitive items such as flexible endoscopes or complex laparoscopicinstruments as the operating temperature is 45°C less than 55°C. The cycle timecan vary from 45–75 minutes but no aeration is required as the byproducts are nontoxic(water vapor and oxygen). A typical cycle consists of a vacuumto remove air, injection and diffusion of the hydrogen peroxide and generation via radio (RF) energy for a defined sterilization time, Venting of filtered air into the chamber through High Efficiency Particulate Air (HEPA) filter Vaporized It is a sterilization method utilizes hydrogen peroxide to kill hydrogen wide spectrum of microorganism through oxidization. Peroxide The cycle takes 28-55 minutes at less than 50 ºc. lumened and non-lumened instruments can be sterilized in these machines based on the program you select. Typical cycle consist of: − Conditioning to remove air and moisture − Leak test − Injection of Hydrogen Peroxide to the chamber for sterilization − Aeration Cellulose – containing packaging material cannot be used in Hydrogen peroxide sterilizers as the absorb the peroxide and interrupt effective sterilization. Ozon This low temperature sterilizationsystem Sterilization eliminates the need for purchasing a sterilant by generatingO3. The processing cycle takes 4 hours and 30 minutes at 30.8-36 °C.The method must be approved by the medical device manufacturer for sterilization. Typical cycle consist of: 1. Vacuum and humidification. 2. Injection of the O3. 3. Sterilization 4.Ventilation  Use Temp.& time Advantages Disadvantages Dry Heat used for glassware -using normal Suitable for non- -High temperatures and metal items, heat pressure aqueous fluids -Unsuitable for heat sensitive stable powders and -cycle time: and glassware items non-aqueous liquids up to 2 hours -Long sterilization and cooling like paraffin times -Items cannot be wrapped steam 1. Gravity 1. Gravity -Highly effective -Moist process. (moist heat) Sterilizers: used for Sterilizers: Cycle -Inexpensive -Unsuitable for heat sensitive 40-60 min solid metal items times are much - Rapid process items. such as non-complex longer. - Items may be 2. Porous Load: packaged surgical instruments. not less than 3 -No toxic residues 2. Porous Load: for mins at 134°C. heat resistant tools. 3. IUSS: 134°C 3. IUSS or flash for 3–10 sterilization: with minutes. dropped instruments. Gas for heat sensitive T: 45°C not less -Suitable for -Non-cellulose wrapping plasma items such as flexible than 55 °C. heat sensitive materials required. endoscopes or The cycle time: 45– devices. -May not be suitable for complex 75 minutes laparoscopic -Short cycle. long narrow lumens. instruments. Ethylene works well for heat T: 37 °C or 55°C -Suitable for heat -Equipment is expensive Oxide sensitive equipment cycle time: sensitive reusable -Lengthy cycle with aeration such as invasive 8-12 hours medical devices and validation (EO) flexible endoscopes, -Extremely -Ethylene oxide gas is toxic, and cardiac and penetrative explosive and flammable ophthalmic devices suitable for -Separate accommodation is lumened devices recommended Items -Lengthy aeration required -may be to remove toxic residues wrapped -Dry process -Non damaging