Ch 14-15 high temp and low temp sterilization
EO safety
A toxic gas classified by OSHA as a Carcinogen and reproductive hazard Sterilizer should be well ventilated with a room air exchange rate of at least 10 changes per hour
Exposure monitoring
Ability to monitor the sterilization process
Safety mechanism... (door, gasket and chamber drain)
Automatically activates when chamber pressure is applied; it can only be unlocked when pressure is exhausted
Loading a steam sterilizer basic procedures:
Avoid overloading, instruments must be placed for efficient air removal, steam penetration, and evacuation Positioning instruments in a way that allows air to exit and steam to enter Ensuring visible space between packs Placing rigid containers on the bottom to prevent condensation dripping onto lower packs Ensuring packages do not touch chamber walls Standing basins on side Positioning textile packs so layers within are perpendicular to shelf Standing peel packs on side using a basket or rack Instrument trays sit flat on the shelf to maintain even distribution and facilitate proper drainage Placing hot or warm packages on a cold surface will cause condensation
Why is steam a most common used sterilant?
Because of its successful record of efficacy, reliability and low cost.
A saturated steam sterilization cycle has four phases:
Conditioning Exposure Exhaust Drying
A print out from a steam sterilizer cycle contains:
Date and time cycle began Selected cycle parameters, such as type of cycle, sterilization temperature, and dry times A written record of actual cycle activities
Prevacuum steam sterilizers
Dynamic air removal autoclaves; vacuum pump is build into the system to remove air. Before steam is injected into the sterilizer, air is removed from the chamber, reducing the total cycle time
To minimize safety risks, employee should be instructed about:
EO hazards Sterilizer manufacturer and EO supplier IFU Processing procedures Storage and handling of EO cartridges Procedures to reduce exposure Use of PPE Monitoring and interpretation of results Handling canceled cycles OSHA regulations Safety data sheets Emergency plans
Ethylene oxide
Effective sterilization method for heat and moisture sensitive medical devices for 60 years Efficacy; excellent, microbial activity, destroys the sales ability to metabolize or reproduce, which leads to the organisms death Penetration - small molecule that vaporizes easily and can permeate throughout a wide range of materials
Steam contact failure:
Failure to adequately clean item Density - instruments positioned in a way that does not allow steam contact Packages wrapped too tightly Loads too crowded Containers positioned incorrectly Clogged drain Mechanical malfunction Utility malfunction
SPD techs should be familiar with two basic sterilization cycles:
Immediate use steam sterilization Terminal sterilization
Door gasket
Is designed to maintain a tight seal that prevents steam from escaping the chamber and air from entering
Sterilization
Is required to kill any remaining micro organisms, including spores. Failure could result in serious, even life-threatening patient outcomes.
Thermostatic trap
Located in the drain line, the drain and surrounding area are the coolest area in the sterilizer, a sensor in the chamber drain measures steam temperature, and automatically controls the flow of air and condensate from the chamber
Advantages of steam sterilization
Low cost Rapid sterilization cycle's Relatively simple technology Leaves no residue or byproducts
Penetration
Must be able to penetrate through packaging materials and into the lumens
Sterilization performance monitoring
Must be capable of being reliably monitored using physical, chemical, and biological indicators
Approval
Must be cleared or registered with appropriate regulatory agencies
Safety
No toxic residuals remaining
Wet packs
Packages are considered wet when moisture in the form of dampness, droplets or puddles of water are found on or within a tray after sterilization Moisture can create a password for micro organisms, to travel from the outside to the inside of instruments A wet pack is considered contaminated and It must be re-processed. Internal moisture will not be noticed until tray is opened for use
Primary causes of wet packs:
Packs loaded incorrectly Heavy or dense instruments Packs wrapped too tightly Improperly prepared items Instruments that are overloaded Improper placement Incorrect filter or placement Gasket not intact Clogged drain Broken valves
Sterilizer monitors
Physical monitoring Chemical monitoring Biological monitoring
Five stages of EO sterilization cycle
Preconditioning and humidification Gas introduction Exposure Evacuation Air washes Cycle takes 2 1/2 to 3 1/2 hours
Cleaning; decontamination
_____________ and _____________ kills most but not all microorganisms
Ethylene oxide; hydrogen peroxide
______________ and ______________ are the low temp sterilization method used in healthcare settings
Low temperature sterilization
________________________ is important due to the development and growing use of heat and moisture sensitive devices
What is the weakest part of the steam sterilizer?
door
Dynamic air removal sterilizers
similar to gravity air displacement sterilizers except vacuum pump or water ejector removes air during preconditioning phase prior to reaching exposure temperature and they usually run at higher temps
Several factors and conditions impact the effectiveness of all sterilization methods...
The type of microorganism's present The design of the medical device The number of microorganisms present The amount and type of soil present
Physical monitors record:
Time, temperature and pressure
Immediate use steam sterilization (IUSS)
Undergo the same cleaning and preparation as items that are terminally sterilized. Located outside SPD. IUSS items should be used immediately.
Personal monitoring
Use of device affixed to employees clothing in the breathing zone
Area monitoring
Used to measure the working area. Where EO sterilizers are used
Physical monitors
Verify that the parameters of the sterilization cycle has been met
High temperature sterilization
Process of choice in many healthcare facilities. It is achieved by subjecting items being processed to thermal energy from moist heat
FDA
Recommends that sterilant be vigorously tested before marketed
Terminal sterilization
Refers to an item that is expected to be dry upon completion of sterilization process
OSHA requires accurate record of all measurements taken to monitor employee exposure:
Sampling in analytical methods used and evidence of their accuracy Number, duration and results of samples taken Type of safety device worn Name of employee exposed Employer maintains records for 30 years
OSHA
Sets exposure standards for sterilant
Adaptability
Should be compatible with existing healthcare practices
Material compatibility
Should be no changes in the functionality of the device
Temperature time
Specific temperatures are needed to kill heat, resistant bacteria. Two most commonly encountered temperatures for steam sterilization: gravity sterilization, 250°F and dynamic air removal 270 to 275°F. Inadequate, sterilization exposure time can lead to failure of the process.
Gravity Air Displacement Sterilizer
Steam enters the chamber, and because air is heavier than steam, the steam forces the cooler air to the bottom and out through the drain
Efficacy
The capability of providing the minimum required stability assurance level
