When using autoclave to sterilize medical equipment, it often fails to sterilize, leading to nosocomial infection accidents.
The sterilization failure of medical autoclave are mainly reflected in the following four reasons:
First, there is too much residual air. Due to excessive residual air inside the sterilizer, bacteria and viruses on the sterilized appliance still remain on the surface, which is difficult to meet the actual sterilization requirements. After a long-term accumulation of experience, found that high pressure sterilization device internal air residues on the sterilization effect is very significant, if the residual air closed sterilization in the parcel do not mix with steam secondary contact, causes the air to form a gas, prevent steam entering, which was disinfected objects was difficult to come into contact with steam, more can’t achieve disinfection. In the process of using traditional pre-vacuum autoclave for sterilization, because the sterilizer has low requirements for sterilization vacuum environment, it only vacuumizes the sterilization chamber once before sterilization, and then vacuumizes again after sterilization to forcibly dry and discharge the gas, resulting in a large amount of residual air and causing sterilization failure.
Second, steam quality control is lax. When using medical autoclaves to carry out sterilization, injecting high pressure and high temperature gas into the sterilization equipment will lead to the destruction of microbial enzymes and structural proteases, so as to achieve sterilization effect. Saturated steam is more penetrating than either hot dry air or superheated steam, so it is necessary to inject saturated steam during the use of autoclave to ensure optimum disinfection. Under normal circumstances, the boiling point of water at different pressures is different. Only when the temperature of water and steam in the container does not rise at a certain pressure can the pressure and temperature meet the requirements of saturation. Compared with other types of steam, saturated steam contains water inside, so it is also called wet saturated steam. Due to the neglect of steam quality inspection in some hospital disinfection departments, steam is often injected into the container before reaching the saturation requirements, resulting in the disinfection effect is always in the stage to be improved, and it is difficult to play an important role in medical infection control.
Third, medical autoclave equipment failure. In the actual use of the vacuum autoclave equipment, the electric door sealing is not good, the temperature is not up to standard and other faults often occur, resulting in a serious impact on the sterilization effect. When the electric door of autoclave equipment is closed, the door rubber strip needs to be extruded from the sealing groove with compressed air. After opening and closing the door for many times, the rubber strip will often be damaged, resulting in gaps when the electric door is closed in the later period, resulting in air entering the vacuum environment. At the same time, the compressed air pressure does not meet the actual requirements, and the sealing effect of the electric door cannot be guaranteed, which seriously affects the effectiveness of the sterilization effect of the medical autoclave.
Moreover, the malfunction of medical autoclave equipment is also reflected in the inner chamber air leakage and other aspects. The inner chamber leakage is mainly the leakage of the pipeline connected with the inner chamber, leading to the sterilization environment is difficult to reach the vacuum standard. As the medical autoclave is in high pressure and high temperature operation environment for a long time, the sealing rubber ring between the pipe junction is very prone to aging, resulting in air leakage. After an air leak occurs in the chamber, air will enter the vacuum, weakening the room temperature and triggering a low temperature alarm.
Fourth, medical high-pressure sterilization equipment is affected by the corrosive effect of chloride ion stress, resulting in incomplete disinfection work, secondary pollution of equipment and other problems. Because in the disinfection process of glassware, there will be a certain dose of hydrochloric acid on the surface of the vessel, which is decomposed into chloride ions under high temperature and high pressure, attached to the surface of the high-pressure sterilization equipment, resulting in different degrees of corrosion on the surface of the equipment, damage and other situations, seriously affecting the disinfection effect.

The above are the problems of the sterilizer equipment itself. There are many reasons for the sterilization failure of the sterilizer. Improper sterilization materials or operation in the sterilization process will also cause the sterilization failure of the sterilizer:
First, improper packaging
Factors include using the wrong type of packaging material for disinfection, placing too many instruments in packaging and wrapping items in too much paper. If the materials used to package the device are incompatible or excessive packaging is used, the sterilization process may not properly touch the device surface, resulting in sterilization failure.
Second, the sterilizer is overloaded
Overloading of the chamber results in a prolonged warm-up time to reach sterilization conditions and may also prevent the sterilizer from coming into full contact with all items in the device. A common problem observed during sterilization failures is insufficient spacing between packaged device packages. Most sterilizers sold in recent years are equipped with a stand or tray, which allows for maximum capacity of the instrument package and effective sterilization of a prescribed cycle. Many older units can also be fitted with usable racks or trays.
Third, the use of improper equipment for sterilization
For autoclave instruments, it is important to ensure that they are compatible with the high temperature and high pressure environment generated within the autoclave. If you’re not careful, this can lead to some serious health and safety hazards that could have been avoided. Your materials should be evaluated before performing sterilization, as some materials may not be thermally stable or designed to withstand higher temperatures.
The advantages of steam sterilizer are very many, it requires operators to use it well, operate it correctly and do a good job in maintenance, so as to better play its value.

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