AUTOCLAVE STERILIZATION PROCESS
Autoclaving uses a combination of high temperatures and pressurized steam to decontaminate items placed in the sterilization chamber. For solid items and porous materials, such as surgical clothing, a vacuum is created in the chamber before the addition of hot steam. This ensures that the steam fully penetrates the material. Liquid materials such as those contained in vials or parenteral (injectable) solutions do not require negative pressure. Steam sterilizers are used to process a large number of products, including surgical and dental instruments, tattoo needles, glassware, and culture media preparations such as agar. Infectious medical waste is often autoclaved before being landfilled. The goal of sterilization is to kill all pathogens that may be present on the material. When the process is done properly, a high level of sterilization assurance is achieved and virtually all microbes are destroyed.
Typical cycle
During the autoclave process, the chamber is loaded with medical instruments. The technician checks the load to make sure it is properly distributed for maximum steam penetration. Chemical and biological indicators can be added to validate the effectiveness of the cycle. The door is then closed and sealed. The user selects a pre-existing cycle or programs new parameters using the touch screen. If the sterilizer has an auto-closing safety mechanism, it will automatically activate when the cycle begins. It will not be released until the process is complete and the load temperature has dropped to a safe level. Steam is then released from the chamber and hot air is used to dry the load. For wrapped instruments, it will be necessary to add a post-vacuum cycle to the drying process. The pressure is then normalized and the load is allowed to cool. The chemical indicator can be checked immediately to see that the proper temperature has been reached during the cycle. The biological indicator must be cultured to see if any microbes are still alive. Many autoclaves have microprocessors and data storage units that can display and/or archive cycle information.
Problem solving
The most common problem in sterile material processing departments is moisture in loads. If moisture is detected in a load at the end of the cycle, it is not considered sterile and must be reprocessed. Technicians can reduce the frequency of these wet loads by using proper loads and packaging. If a hot instrument tray is removed from the autoclave early, moisture from the air (contaminated with germs) immediately begins to form condensation on exposed surfaces. To prevent this problem, it must be ensured that the drying and cooling phases of the cycle are not shortened.
