In Russia, all institutions engaged in medical activities are required to work according to strict standards, among which an important place is occupied by the proper disinfection and sterilization of medical devices.
Why follow the standard
Today, many people, even far from medicine, are familiar with such a term as nosocomial infection. It includes any disease that the patient receives either as a result of his seeking help from a medical institution, or the organization's staff in the performance of their functional duties. According to statistics, in surgical hospitals, the level of purulent-inflammatory complications after clean operations is 12-16%, in gynecological departments, complications after operations develop in 11-14% of women. After studying the structure of the incidence, it became obvious that from 7 to 14% of newborns become infected in maternity hospitals and children's departments.
Of course, such a picture can be observed far fromin all medical organizations and their prevalence depends on many factors, such as the type of institution, the nature of the assistance provided, the intensity of the mechanisms for the transmission of nosocomial infections, and its structure. Against this background, one of the main non-specific measures to prevent the occurrence and transmission of nosocomial infection is the disinfection and sterilization of medical devices.
Regulatory documents
In their work, all he alth facilities are guided by the recommendations recorded in many regulatory documents. The fundamental document is SanPiN (disinfection and sterilization of medical devices is highlighted in a separate section). The latest revision was approved in 2010. The following regulations also apply to determine the work of medical institutions.
- FZ No. 52, which declares measures for the epidemiological safety of the population.
- Order No. 408 (on viral hepatitis) of 1984-12-07.
- Order No. 720 (to combat HAI).
- Order of 1999-03-09 (on the development of disinfection).
OST "Sterilization and disinfection of medical devices" No. 42-21-2-85 is also one of the main documents regulating the standard for processing instruments. It is he who guides all medical institutions in their work.
In addition, there are a large number of guidelines (MU), the disinfection and sterilization of medical devices which is considered from the point ofview of the various disinfectants approved for this purpose. Today, due to the fact that many dis. means, relevant guidelines are also an integral part of the documents on which the work of he alth facilities is based. To date, the standard for processing instruments consists of three consecutive stages - disinfection, PSO and sterilization of medical devices.
Disinfection
Disinfection is a set of measures, as a result of which pathogenic microorganisms are destroyed on environmental objects. These include surfaces (walls, floors, windows, hard furniture, equipment surfaces), patient care items (linens, dishes, sanitary ware), as well as bodily fluids, patient secretions, etc.
In the identified focus of infection, activities are carried out called “focal disinfection”. Its purpose is the destruction of pathogens directly in the identified focus. There are the following types of focal disinfection:
- current - it is carried out in medical institutions in order to prevent the spread of infection;
- final - carried out after the source of infection is isolated, that is, the sick person has been hospitalized.
In addition, there is preventive disinfection. Its activities are carried out constantly, regardless of the presence of an infectious focus. This includes washing hands, cleaning surrounding surfaces with products that have bactericidal additives.
Disinfection methods
Depending on the goals, the following disinfection methods are used:
- mechanical: it refers directly to the mechanical impact on the object - wet cleaning, shaking or knocking out bedding - it does not destroy pathogenic microorganisms, but only temporarily reduces their number;
- physical: exposure to ultraviolet, high or low temperatures - in this case, destruction occurs if the temperature regime and exposure time are strictly observed;
- chemical: destruction of pathogenic microorganisms with the help of chemicals - immersion, wiping or spraying the object with a chemical solution (is the most common and effective method);
- biological - in this case, an antagonist of the microorganism to be destroyed is used (most often used at specialized bacteriological stations);
- combined - combines several methods of disinfection.
OST “Sterilization and disinfection of medical devices” 42-21-2-85 states that all objects and instruments with which the patient has had contact must go through the disinfection process. In he althcare facilities, a physical or chemical method of disinfection is used for this. After its completion, the products, depending on their purpose, are further processed, disposed of or reused.
Pre-sterilization cleaning
Disinfection and sterilization of medical devices forreusable instruments to be sterilized also provides for pre-sterilization cleaning, which takes place after the disinfection of the product. The purpose of this stage is the final mechanical removal of residues of fatty and protein contaminants, as well as medicines.
The new SanPiN, disinfection and sterilization of medical devices, which is considered in sufficient detail, provides for the following stages of PSO.
- For 0.5 minutes, the product is washed under running water to remove residual disinfectant solution.
- In a detergent solution, for the manufacture of which only approved products are used, the products are soaked when fully immersed. In the event that they consist of several parts of the product, it is necessary to disassemble and make sure that all existing cavities are filled with a solution. At a washing solution temperature of 50º, the exposure time is 15 minutes.
- After the time has elapsed, each product is washed with a ruff or gauze swab for 0.5 minutes in the same solution.
- Rinse the products under running water. The duration of rinsing depends on the product used ("Astra", "Lotus" - 10 minutes, "Progress" - 5, "Biolot" - 3).
- Rinse in distilled water for 30 seconds.
- Drying in a hot air oven.
To prepare a washing solution, use 5 g of SMS ("Progress", "Astra", "Lotus", "Biolot"), 33% perhydrol - 16 g, or 27.5% - 17 g. It is also allowed to use 6% (85 g) and 3% (170 g) peroxideshydrogen, drinking water - up to 1 liter.
Modern means used for disinfection make it possible to combine disinfection and PSO processes. In this case, after the end of the exposure, directly in the des. solution, the tools are brushed and then all subsequent stages of the PSO.
Quality control
SP, disinfection and sterilization of medical devices, which are painted literally step by step, pay great attention to the quality control of each stage of processing. To do this, tests are carried out that control the absence of blood, other protein compounds on the processed product, as well as the quality of washing off detergents. One percent of the processed instrumentation is subjected to control.
The phenolphthalein test allows you to evaluate how thoroughly the detergents that were used in pre-sterilization cleaning were removed from the products. To put it on a swab, apply a small amount of a ready-made 1% solution of phenolphthalein and then wipe those products that they want to check. If a pink coloration appears, the quality of washing off of detergents is considered insufficient.
Disinfection and sterilization of medical devices require control at each stage, and another test that allows you to assess how well the first stages were carried out is the azopyram test. It evaluates the presence or absence of blood and medicinal substances on them. To carry it out, you need a solution of azopyram,which, when cooked, can be stored for 2 months in the refrigerator (at room temperature, this period is reduced to one month). Some turbidity of the reagent in the absence of sediment does not affect its quality.
For the test, immediately before it is carried out, the same amount of azopyram and 3% hydrogen peroxide are mixed and applied to the blood spot for verification. The appearance of a purple color means that the reagent is working - you can start testing. To do this, moisten a swab with the prepared reagent and wipe the surfaces of tools and equipment. In products with hollow channels, a few drops of the reagent are placed inside and after 1 minute the result is evaluated, paying special attention to the joints. In the event that a purple color appears, gradually turning into a pink-lilac color, the presence of blood is ascertained. Brownish color indicates the presence of rust, and purple indicates chlorine-containing substances.
To correctly evaluate the results of the azopyram test, several points must be taken into account:
- a positive sample is considered only if the staining appeared within the first minute after applying the reagent;
- working solution can only be used within the first two hours after preparation;
- products must be at room temperature (on a hot surface, the sample will not be informative);
- regardless of the results, the products testedwashed with water and again subjected to presterization cleaning.
If positive results are obtained after testing, the entire batch is re-treated until a negative result is obtained.
Sterilization
Sterilization is the final step in the processing of those products that have contact with the wound surface, mucous membranes or blood, as well as injectables. In this case, there is a complete destruction of all forms of microorganisms, both vegetative and spore. Carrying out all manipulations is regulated in detail by such a normative document of the Ministry of He alth as an order. Sterilization and disinfection of medical devices are carried out according to the specifics of the medical institution and their purpose. Sterilized products can be stored, depending on the packaging, from a day to six months.
Sterilization Methods
Methods for disinfection and sterilization of medical devices are somewhat different from each other. Sterilization is carried out by the following methods:
- thermal - air, steam, glasperleny;
- chemical - gas or in solutions of chemicals;
- plasma or ozone;
- radiation.
In medical institutions, as a rule, steam, air or chemical methods are used. At the same time, the most important component of the sterilization process is the careful observance of the established regimes (time, temperature, pressure). The mode of disinfection and sterilization of medical devices is selected independing on the material from which the workpiece is made.
Air method
Thus, medical instruments, parts of apparatuses and devices made of metal, glass and silicone rubber are sterilized. Products must be thoroughly dried before sterilization cycle.
The maximum deviation from the temperature regime with this method of sterilization should not exceed 3 ° C.
| Temperature | Time | Control |
| 200° | 30 minutes | Mercury thermometer |
| 180° | 60 minutes | Hydroquinone, thiourea, tartaric acid |
| 160° | 150 minutes | Levomycetin |
Steam method
The steam method is by far the most widely used, which is associated with a short cycle, the possibility of using it to sterilize products made from non-heat-resistant materials (linen, suture and dressing material, rubber, plastic, latex products). Sterility in this method is achieved through the use of steam supplied under excess pressure. This happens in a steam sterilizer or in an autoclave.
| Pressure | Temperature | Time | Control |
| 2, 0 | 132° | 20 minutes | IP-132, urea, nicotinamide |
| 1, 1 | 120° | 45 minutes | IC-120, benzoic acid |
| 2, 1 | 134° | 5 minutes | Urea |
| 0, 5 | 110° | 180 minutes | Antipyrine, resorcinol |
Deviations in pressure modes are allowed up to 2 kg / m², and temperature conditions - 1-2 °.
Glasperlen sterilization
The technical support of medical institutions has improved significantly in recent years and this is noted in the latest SP (disinfection and sterilization of medical devices). A new sterilization method that has become widely used in he alth care facilities is glasperlene sterilization. It consists in immersing the instruments in the medium of glass granules heated to 190 - 330 °. The sterilization process takes minutes, and then the instrumentation is ready for use. The disadvantage of this method is that it can only secure small instruments, so it is used mainly in dental departments.
Disinfection, pre-sterilization cleaning, sterilization of medical devices are the most important elements in the workmodern hospitals. The he alth of both patients and medical personnel will depend on how carefully all the measures that are enshrined in the regulations approved by the Ministry of He alth of the Russian Federation are carried out.
