ch. 14, 15 and 17 sur 123
chamber drain
on most sterilizers, it is located at the front or center of the floor. the drain screen must be cleaned at least daily, and more often as needed.
types of vaporized hydrogen peroxide systems
one system has a single preprogrammed, 55 min cycle for use with both lumen and non lumen instruments and devices. the second system offers two preprogrammed cycles: a 28 minute cycle for non-lumened instruments and a 55 min cycle used to sterilize instruments with lumens and not stainless steel mated surfaces.
loading and unloading EtO sterilizers
overloading impedes proper air removal, load humidification, sterilant penetration and aeration. items should be arranged to avoid contact with chamber walls. pouches should be placed on edge in wire baskets. stacking should be avoided.
packaging hydrogen peroxide gas plasma
packaging material should be used in the sterilizers to optimize diffusion and not interfere with RF energy. cellulose packaging materials should not be used with hydrogen peroxide gas plasma because they absorb the peroxide and inhibit effective penetration.
causes of wet packs
packs that were improperly prepared or loaded incorrectly for sterilization. heavy of dense instruments sets. not using absorbent material to wick moisture between heavy metal, such as basin sets. textile packs wrapped too tightly. improperly prepared items. metal items positioned in a way. that allows water to pool of trap steam. linen packs wrapped too tightly. improper placement of concave items. and not using the correct filters or incorrect filter placement on a container.
exposure monitoring
personal monitoring normally involves the use of devices affixed directly to the employee's clothing in the breathing zone to test airborne EtO concentration.
sterilization performance monitors of hydrogen peroxide gas plasma
physical monitors, chemical monitoring, and biological indicators ( Geobacillus stearothermophilus spores.)
sterilization performance monitors
physical monitors, chemical monitors, biological monitoring. The microorganism of choice for EtO is Bacillus atrophaeus.
EtO employees should be instructed about...
processing procedures, storage and handling of EtO gas cartridges, procedures to reduce employee exposure, Use of PPE, principles of EtO monitoring and interpretation of results, handling canceled cycles, applicable OSHA standards, SDS, and EtO emergency plans.
sterilization cycle and process parameters
the basic cycle consists of five stages: preconditioning and humidification, gas introduction, exposure, evacuation and air washes. the cycle takes 2.5 hours to complete. the cycle should go through an aeration cycle to remove all residue.
unloading a steam sterilization
the cooling time should be only 30 mins for small sets or peel packs. for sterilizers without carts, items should remain in the sterilizer chamber until properly cooled. the load contents should be visibly free of any liquid. wet items should be contaminated, even if they have not been touched.
door, gasket and chamber drain
the door is the weakest part of the steam sterilizer. it has a safety locking mechanism the automatically activates when chamber pressure is applied and it can only be unlocked when pressure is exhausted.
pre vacuum steam sterilizers
the dynamic air removal cycle depends on one or more pressure and vacuum sequences at the beginning of the cycle to remove air during the preconditioning phase.
steam sterilizer jacket
the jacket surrounds the sides, top and bottom of the vessel, and steam circulates in this space to pre heat the interior chamber walls.
ethylene oxide sterilizers
the microorganism of choice for EtO is bacillus atrophaeus spore. should be run in every EtO load.
moisture
the moisture content of saturated steam should posses a relative humidity of 97-100 percent. steam should consist of two to three parts of saturated water and 97 to 98 parts dry, saturated steam.
contact
the most common reason for sterilization failure is the lack of contact between steam and the entire surface of the device being sterilized.
temperatures
the most commonly encountered temperature for steam sterilization are : gravity sterilization 250 F and dynamic air removal 270 F to 275 F
steam
the most frequently used sterilant for devices not adversely affected by moisture or heat because of its successful record or safety.
bioburden
the number of microorganisms on a contaminated object.
julian date
the number of the days that have elapsed since January 1.
aeration
the process in which sterilized packages are subjected to moving air to facilitate removal of toxic residuals after exposure to a sterilization agent.
gauges and controls
the sterilizer's gauges and/or controls provide a visual and written record sterilization conditions. a printout from a steam sterilization cycle usually contains: date and time, selected cycle parameters, and a written record of actual cycle activities.
factors that impact sterilization
the type of microorganism present, the design of the medical device, the number of microorganisms, and the amount and type of soil present.
immediate use steam sterilizers
their intended use if for the emergency sterilization of instruments when there is not enough time for terminal sterilization.
process indicators
there are two basic types: internal chemical indicators, and external CIs.
tabletop sterilizers
these units operate by having water poured into the sterilizer , either through a port or the bottom of the chamber and are electrically heated until the water turns into steam. at the end of the cycle the relief valve opens to allow the steam to escape. the steam passes through the water reservoir where it condenses back to water. after the pressure dropped to zero, the door can be opened.
hydrogen peroxide gas plasma
this method is popular due to its safety, relative to EtO, and its rapid cycle times that allow faster turnaround of medical devices. the byproducts of the cycle are nontoxic, eliminating the need for a lengthy aeration phase.
physical monitors include:
time, temperature, pressure recorders, displays, digital printouts and gauges.
dynamic air removal sterilizers
to gravity air displacement sterilizers, except there is a vacuum pump or water ejector. dynamic air removal sterilizers usually operate at higher temperatures than gravity sterilizers.
extended sterilization cycles
CS technicians must obtain, review and consistently follow the manufacturers written recommendations for all of the medical devices they process.
efficiency of EtO
EtO has excellent microbicidal activity. during the alkylation process, EtO destroys the cell's ability to metabolize or reproduce, which leads the the organism's death.
safety of EtO
EtO isa toxic gas classified by OSHA as a carcinogenic and reproductive hazard. EtO sterilizers should be located in a well ventilated area, with a room air exchange rate of at least 10 changes per hour.
packaging
EtO sterilization is compatible with a variety of packaging materials, such as paper/plastic or Tyvek peel pouches, approved fabric wrappers, medical crepe paper, polypropylene and most container systems.
vaporized hydrogen peroxide
Low temperature sterilization technology utilizing VHP has been available to hospitals since 2007. VHP systems utilize an oxidative process and provide a rapid cycle time that improves the throughput of medical devices and surgical instruments.
ozone sterilization
O3 is a low temperature sterilization method that received FDA clearance in 2003. does not require aeration and medical devices and surgical instruments can be used as soon as the 4.5 hour cycle is complete.
exposure
after the desired temperature is reached, the sterilizer's control system begins timing the cycle's exposure phase. .
preparing devices and packs for steam sterilization
air removal, steam penetration and condensate drainage are enhanced by proper positioning, and by the use of perforated or mesh bottom trays or baskets.
loading a steam sterilizer
allow for proper steam penetration and avoid overloading. if a shelf liner is used, it should only be made of absorbent material. solid containers must be positioned so air can exit and steam can enter. there should be visible space between packs to allow steam circulation and drying. when combining loads, place hard goods on the bottom. packages must not touch chamber walls. basin sets should stand on edge. position textile packs so the layers within them are perpendicular to the shelf. stand paper/plastic peel pouches on edge using a basket or rack. sterilize textiles and hard goods in separate loads. surgical instrument trays with perforated bottoms should sit flat on the shelf to maintain even instrument distribution.
dynamic air removal sterilizer
also known as the bowie dick test. it is a class C CI, known as a specialty indicator. the only item that should be in the chamber during the test are the sterilizer loading carriage.
residual EtO
amount of EtO that remains inside materials after they are sterilized.
irrigating ultrasonic cleaners
are used to help clean lumened instruments. use a cavitation process, but they employ irrigating tubes that flush solution through each lumen.
safety of O3
at low levels, it is a respiratory irritant. OSHA, FDA, and NIOSH regulate O3 as a toxic gas, O3 is a bluish gas with a strong odor. the odor threshold for humans is .003 and .01 ppm. it is possible to detect O3 at a concentration lower than the exposure limit for an eight hour period, which is .01 ppm.
conditioning
at the beginning of the sterilization cycle ,the steam enters at the upper back . air gets displaced through the drain, and pressure and temperature start to rise.
exhaust
at the end of the exposure phase, the chamber's drain is opened and the steam is removed through the discharge line.
other causes of wet packs
broken valves, malfunctioning steam traps or drain check valves, faulty sterilizer gauges or controllers, clogged drain lines, and faulty drain valves.
leak testing
check the sterilizer's ability to hold a vacuum by testing all the seal areas and piping to ensure air is not allowing into the chamber during a cycle's vacuum phase. leak tests should be performed at least weekly
water quality
cleaning chemical must be used with the recommended water pH and will not function as designed if the water's pH is incompatible with the chemical.
cleaning and maintaining sterilizers
cool the chamber before any cleaning or maintenance procedure. the chamber drain sterilizer should be removed at least daily and cleaned thoroughly under running water using a non- abrasive brush and a mild detergent. the inside of the chamber should be cleaned according to the manufacturers instructions. the door gasket should be inspected and wiped down daily. carriages, carts and loading baskets should be cleaned with a mild solution. strong abrasive or strong wool should never be used the sterilizer. inspect recording devices daily.
Immediate use steam sterilizer information that needs to be tested
date , sterilizer identification, cycle temperature and sterilization time, items being sterilized, patients identification, reason for sterilizing the item using IUSS, CI results, and BI results.
CS technicians are responsible for
determining if all sterilization parameters were met and if the load may be released. if any steam sterilization should be notified immediately and the sterilization load should not be released.
to unload sterile items...
do not unload packages before they are cool. handle the sterile packages as little as possible.
Ethylene oxide
effective for heat and moisture sensitive items.
low temperature sterilization requirements
effectiveness, safety( no toxic residue left on the instruments), exposure monitoring, sterilization performance monitoring, penetration, material compatibility, adaptability, and approval.
frequent causes of steam contact failure
failure to adequately clean the object being sterilized, sets that are too dense or instruments positioned in a way that does not allow steam contact, packages wrapped too tightly, loads that are too crowded, containers that are positioned incorrectly, clogged drain strainers, mechanical malfunctions, and utility malfunctions.
efficacy of O3
generate sterilant using medical grade oxygen and water. O3 is highly effective as an oxidizing agent for low temperature sterilization. sterilizes by oxidizing proteins and enzymes, causing the death of the organism.
low temp sterilization
has become increasingly important because of the development and growing use of delicate, heat and moisture sensitive medical devices and surgical instruments. EtO, hydrogen peroxide and ozone are the low temp sterilization methods used.
saturated steam sterilization cycle
has three phases: conditioning, exposure, exhaust, and drying.
Many AERs
have a physical printout of the cycle that is available after the cycle is complete. the printout needs to be monitored to see if the parameters were properly met, and then signed.
the importance of accurate records
having incomplete records is the same as having no records at all. Facts about CS department records: record keeping is mandatory, records must be accurate, records must be legible and understandable, records must be complete, and records should be audited routinely.
to minimize O3 risks, employees should be instructed about
hazards of O3, handling canceled loads, applicable SDS, and applicable OSHA standards.
efficacy
hydrogen peroxide gas plasma using a hydrogen peroxide solution ranging from 59 percent to 95 percent for the sterilization cycle is proven effective at killing microorganisms.
biological indicators
if the bacteria have been killed, there will be no color change or indication of life during incubation. this is known as a negative test result. a test ampule called a control, should be run at least daily, when a BI is run, and each time a new lot is opened.
decontamination area monitoring
important to ensure all cleaning equipment is working properly.
Penetration of O3
is a contact sterilant. is highly reactive and has penetration limitations similar to hydrogen peroxide.
a wet pack
is considered contaminated and must be completely repackaged and reprocessed. when doing so, all textiles should be re-laundered and process indicators in the tray or pack must be replaced.
penetration
use deep vacuums, multiple pulse additions of the sterilants and increased concentrations. can sterilize a wide range of instruments. concentrations go up to 95 percent.
reasons for positive biological monitors
using the wrong BI of PCD. incorrect placement of the BI in the sterilizer load. not following the BI manufacturers IFU. Incorrect storage of the BI. incorrect cycle selection. not loading the sterilizer cart to allow for air removal and sterilant penetration around and through the load.
causes of a CI test failure
utility or sterilizer malfunction, inappropriate sterilizer loading techniques, not using the correct CI monitor, wrong cycle selected, poor storage of the CI indicator, improper packaging techniques, and not following the instructions.
sterilization cycle and process parameters
vacuum, injection, diffusion, plasma, and vent.
validation vs verification
validation is done by the device manufacturers using a documented procedure to obtain, record and interpret the testing results required to determine a process consistently produce a sterile product. validation requires extensive laboratory testing and retesting. verification is performed to confirm that the validation is application to the specific equipment and settings in their facility.
steam flush pressure pulse sterilizers
SFPP sterilizers use a repeated sequence of a steam flush and pressure pulse to remove air form the sterilizer chamber and processed materials. air removal occurs above atmospheric pressure; no vacuum is required. Like a pre vacuum sterilizers , this process rapidly removes air from the sterilizer's chamber and wrapped items.
advantages of steam sterilization
its low cost, rapid sterilization, relatively simple technology, and leaves no chemical residue or byproducts.
hydrogen gas plasma is not compatible with:
liquids and powders, any material that absorbs liquids, and items that contain cellulose , such as cotton, paper or cardboard, linens, huck towels, gauze sponges or any item containing pulp.
EtO should not be used to sterilize..
liquids, devices with energy sources, and leather items.
thermostatic trap
located in the drain line. a sensor in the chamber drain measures steam temperature and automatically controls the flow of air and condensate.
safety
many of the sterilants are dangerous to use.low temperature sterilization systems should be used by manufactures instructions and appropriate work practices, engineering controls, PPE and monitoring should be employed.
aeration
minimum general recommendations for aeration are 8 hours at 140 F and 12 hours at 122 F.
cart washers
must be monitored to ensure they are working properly. floor screens should be checked at least daily.
manual disinfection monitoring
must have: date, test strip results, expiration date of the test strip and disinfecting solution, and items disinfected.
penetration
must penetrate package material and must reach all narrow lumens. EtO inactivates microbes by a process called alkylation. hydrogen peroxide destroys microbes through oxidation. it is important to place chemical indicators in the most difficult to sterilization area of the load.
documenting disinfected flexible or rigid endoscopes
name of the technician who cleaned the scope, and name of the patient on whom the scope was used.
formal monitoring of the physical environment
required. for example room temperature and humidity must be monitored at least daily to ensure they meet the established standard.
the Four R's
run, read, record, and retain.
washer disinfectants
should be visually checked daily to ensure screen are clean and that rotating arms are properly attached, rotating and unclogged. should be tested for proper cleaning abilities. the physical monitor is the cycle printout or date log.
general monitoring
some monitoring is informal, such as watching to ensure the everyone who enters the area is dressed appropriately, practices good hand hygiene and follow established traffic control guidelines.
mechanical cleaning equipment
specific test are available for each type of equipment. all test results should be documented.
gravity air displacement sterilizers
steam enters the chamber and because air is heavier than steam, the steam forces the cooler air to the bottom of the chamber and out of the drain.
factors outside of CS that contribute to wet packs
steam quality that does not meet the requirements of the sterilizer, blocked steam lines, boiler feed water that contains too many non condensable gases, boiler not properly maintained, malfunctioning steam traps or check valves, poorly engineered steam piping, and increased demands for the steam supply.
saturated steam
steam that contains the maximum amount of water vapor.
chemical disinfectant monitoring
test the efficiency of the strips. document the date the strips are opened and the final date the strips may be used. document the test results.
