STERILIZERS — devices for killing of microorganisms on surgical instruments, syringes, a dressing material, operational linen, products from thermolabile materials, in injection solutions of pharmaceuticals, on ware and other medical and microbiological objects by means of high temperature or chemicals.
For the first time J. Lister came to a conclusion about need, starting operation, to destroy the bacteria which are airborne and on the objects touching a wound (a dressing material, surgical instruments etc.). Expediency of sterilization by heated air is proved by L. Pasteur (see Pasteur the furnace). Pernicious effect of water vapor on microflora was established by R. Koch. In 1890
A. D. Pavlovsky entered into practice boiling of surgical instruments in 1% soda solution. L. L. Geydenreykh proved that steam sterilization at supertension is most perfect; in 1884 it improved a design of the autoclave that allowed to use the autoclave for sterilization of mediums (see. Autoclave ).
In the USSR V. I. Vashkov, M. Ya. Kapustin, E. S. Krupin, N. V. Ramkova, P. I. Ryabov, G. I. Turner, V. N. Frosin were engaged in development and improvement of the sterilizing equipment, etc.
S. on a design subdivide on stationary, figurative and used in mobile caravans, horizontal and vertical, rectangular and round, with unilateral and bilateral loading and unloading of the sterilized objects, general purpose and special, fire, electrofire, electric and parosetevy, on character of the acting agent — on steam, air (dry-heat) and gas.
Steam sterilizers are economic, effective and reliable that it is connected with big penetration of steam. It is especially important for the materials having low heat conductivity (linen, dressing and suture materials etc.). Steam S. usually consist of the sterilizing camera, the steam generator, control and measuring and recorders, system of providing the mode of sterilization, mechanisms for ensuring loading and unloading of objects of sterilization.
The simplest steam S. is fire S. of general purpose of VKO-4 (fig. 1). At operation in S. pour water and insert cartridges with the syringes placed in them, needles or other tools. Sterilization (see) it is made within 30 min. then pressure in S., exhausting, is removed and take cartridges. Earlier Koch's device was used to these purposes. The elementary devices for disinfection of surgical instruments, needles, syringes in a boiling water with an atmospheric pressure are disinfection boilers (see. Disinfection devices ), to-rye before 70th called sterilizers.
In VKU-50 and VKU-50-1 Page water heats up electric heaters or by means of heat received from a foreign source. Unlike fire S. they have the built-in heatelectric heaters.
The most widespread of steam S. are electric S. of general purpose. They are supplied with electric heaters, devices for automatic maintenance of the mode of the sterilization controlling and the data-acquisition equipment. Loading of materials is carried out in sterilizing boxes (see).
In S.'s most the largest steam pressure 2,2 kg*s/cm 2 (215,7 kPa).
Special S. (for solutions) is intended by GK-100 (fig. 2) for sterilization of injection solutions in hermetically to the corked ware. Of general purpose it differs in existence of the device for creation of counter-pressure in the sterilizing camera from electric S. and system of forced water cooling of objects of sterilization.
Air, or dry-heat, sterilizers are applied to sterilization of glassware, metal, tools with the thin cutting and pricking edges and other objects which are not maintaining wet steam processing. Air S. consist of the thermoisolated case, a round or rectangular (fig. 3) form, the sterilizing camera, inside a cut there are loading grids, heating elements, automatic devices for ensuring air circulation, kontrolnoizmeritelny and recorders.
Air sterilization is carried out also in drying and sterilizing cases (see. Drying ovens ).
Gas sterilizers are applied to sterilization of products from thermolabile materials. In the USSR the method of sterilization using ethylene oxide and bromide is developed marked (mix ABOUT), the equipment for its implementation — gas S. like gpd-250 is created and the mode of sterilization is fulfilled; it is designed also gas by GK-100 Page using as the sterilizing agent of formaldehyde. In the USA, Germany, England, Sweden, ChSSR and other countries there are devices using ethylene oxide in mix with inert gases.
The nomenclature and the main technical characteristics of S. are provided in the table.
The centralized sterilizing. In the USSR, Germany, the USA, Sweden, GDR, Finland, ChSSR and other countries in large-tsakh (on 1000 and more beds) will be organized centralized sterilizing (see. The scientific organization of work) with the special equipment — sterilizing cases with the bilateral loading and unloading of materials, washing machines centralized by sterilizing installations (fig. 4) to-rye represent a wall with the built-in bilateral S.' set and the block of steam generators with the mechanized loading and unloading of the sterilized objects. The domestic industry releases 8 types of the centralized sterilizing installation (CSI), including on tension 220 and 380 in, with a three-chambered or four-chamber steam sterilizer, with an air sterilizer or without it. The maximal working pressure in steam generators of 2,5 kg» with! cm '1 (250 kPa). Time necessary for receiving steam of working pressure does not exceed 55 min. Installation provides three modes of sterilization — for operational linen and dressing materials, for surgical instruments and for products from rubber respectively 132, 126 and 120 ° and sterilizing exposure of 20, 30 and 45 min.
Special sterilizers are established on the chassis of cars and trailers, and also on vessels. The elements ensuring reliable functioning of S. during the movement (ship) or at a stop for expansion of sterilizing devices are provided in their design (on the car or the trailer). The technical characteristic of ship VK-32 and V K-78 Pages is given in the table. On the ste-rilizatsionno-distillation SDP-2 trailer the sterilizing camera with a conditional volume of 75 dm3 and to dia is mounted. 400 mm. Power supply of the camera is carried out from the steam generator with a productivity of 90 kg! hour, using liquid fuel.
Steam S.' operation shall be made according to «Rules for the Construction and Safe Operation of the vessels working under pressure» (on May 19, 1970) and additions (on December 25, 1973) approved by Gosgortekhnadzor of the USSR and also «User Rules for Operating Electrical Equipment and User Safety Rules for Operating Electrical Equipment» (are approved by Gosenergonadzor of the USSR on April 12, 1969), «Rules on operation and the accident prevention during the work on autoclaves» (M3 of the USSR are approved on March 30, 1971). At electric S.' operation it is necessary to follow safety regulationss at operation of electroinstallations up to 1000 century. Gas S. shall service 2 persons.
See also Sterilizing .
Table. MAIN TECHNICAL CHARACTERISTICS of DOMESTIC STERILIZERS
Bibliography: Alekseeva M. I. ides of river. Steam sterilizers and sterilizing installations for the centralized sterilizing departments, Saturday. nauch. works Mosk. nauch. - issled. in-that vaccines and serums, century 26, page 122, 1977; Andrianov V. A. Steam medical sterilizers of BK-30-1 and VK-75-1, Medical tekhn., No. 1, page 46, 1981; In and sh to about in V. I. and d river. Use of a gas method for sterilization of products of medical prescription, in the same place, No. 6, page 18, 1974; In I shopping mall and A. S's N. Figurative steam sterilizer of VKO-4, in the same place, No. 1, page 60, 1979; Problems of disinfection and sterilization, under the editorship of T. I. Istomina, the p. 2, page 12, 44, M., 1977; Rabinky B. Ya., Biryukov V. V. and Unsociable persons of H. M. The sterilizing centralized TsSU-1000 installations, Medical tekhn., No. 2, page 48, 1976; Rabinky B. Ya., Satin V. P. and V. P's Nuts. Steam sterilizers of GK-100 and GP-400, in the same place, No. 5, page 60, 1980; Savelyev G. I. Steam sterilizers with bizonal service and computer-controlled, in the same place, No. 6, page 40, 1974; Frosin V. N., Tsibikov V. B. and Rabinky B. Ya. Medical sterilizers, M., 1981, bibliogr.; Shch e r-and to about in N. P., etc. Rectangular sterilizing boxes with filters, Medical tekhn., No. 2, page 47, 1976.
Yu. A. Shvedov.