There are many kinds of instruments and other articles used in the operation, including metal products, glass, enamel, cotton cloth, plastic, nylon and rubber products, which may cause direct or indirect contact infection to the operation. There are many methods of sterilization, and sterilization should be selected according to the corrosion resistance and high pressure resistance of articles.
1. Metal instruments
All surgical instruments should be clean and free of dust. First of all, check whether enough instruments are prepared to meet the needs of the surgical process. Pay more attention to the performance of each instrument to ensure normal use. For instruments that are not commonly used or newly used, warm detergent solution should be used to remove the protective oil or other protective agents on the surface, and then a large amount of clean water should be used to wash away the remaining detergent for later use. Instruments with complicated structures should be disassembled or semi-disassembled for full sterilization. For hemostatic forceps and needle holder with elastic lock, the lock should be loosened to avoid affecting the elasticity. Sharp instruments should be wrapped in gauze to avoid dulling. Injection needles and sewing needles should be placed in a certain container or inserted on gauze pieces to prevent inconvenience caused by scattering. In order to protect the sharpness of the surgical blade, it is best to wrap it in gauze and soak it in chemical liquid for disinfection (do not autoclave). The surgical instruments used each time can be wrapped in a larger cloth, which is more convenient for disinfection and use.
The most commonly used sterilization method of surgical instruments is high pressure steam sterilization. In case of emergency or unconditional, boiling method or chemical drug soaking disinfection method can also be used.
2. Glass, porcelain and enamel ware
These articles should be thoroughly cleaned, and fragile articles should be properly wrapped and protected with gauze. If this kind of vessel is small in size, it can be sterilized by high-pressure steam, boiled or soaked in chemical disinfection drugs (glassware should not be quenched and heated to avoid damage). If a glass syringe is needed for surgery, the inner plug and outer tube of the syringe should be wrapped with gauze to avoid confusion or collision. When the metal syringe is disinfected, the metal syringe should be cleaned first, and its parts should be disassembled and wrapped with a disinfectant towel. Large quantities of syringes should be sterilized by high-pressure steam, and small quantities should be sterilized by boiling. After sterilization, take it out with sterilized dressing forceps or tweezers and install it in a sterile state. Large vessels, such as square plates and porcelain-lined pots, can be disinfected by burning with alcohol flame, that is, a proper amount of medical alcohol (95%) is poured into clean large vessels to cover the bottom of the plates and ignite them in time.
3. Rubber, latex, nylon and plastic products include all kinds of intubation and catheter, gloves, rubber cloth, apron and all kinds of plastic products commonly used in clinic. Some can't stand high pressure, while others can't stand high heat. These items should be cleaned before disinfection, and fully washed with clear water for later use. When sterilizing, articles should be wrapped in gauze. Latex products can be sterilized by high-pressure steam, generally only once, or soaked in chemical disinfectants, but some disinfectants are easy to cause chemical reactions, such as bromogeramine, which can make the surface of latex gloves sticky (without affecting surgery). Rubber products can be sterilized by high-pressure steam (easy to age, sticky and lose elasticity) or boiling, or by soaking in chemical disinfectants. Some special cannulas and catheters can also be fumigated and disinfected with formaldehyde in small closed containers (such as dryers). At present, many of these items are disposable, which can reduce many complicated links in disinfection work, but their economic cost is high, which increases medical expenses.
Plastic products such as plastic pipes and plastic films are generally disinfected by chemical methods. Some medical units have the conditions to use ethylene oxide gas sterilization devices, which can kill bacteria, spores, rickettsia and viruses, and can be used to sterilize instruments, instruments, dressings, rubber and plastics, which will make the disinfection and sterilization of many surgical supplies convenient and simple.
4 dressings, surgical towels, surgical gowns and masks.
Dressing mainly refers to hemostatic gauze in operation. Hemostatic gauze is made of medical absorbent gauze. According to the specific needs, cut into square gauze pieces of different sizes, which look like handkerchiefs, and then fold them in half until the trimmed burrs are completely folded inside. Then, several pieces of this hemostatic gauze are wrapped in pure cotton square towels into small bags, which is convenient for disinfection and use. At present, surgical towels, surgical gowns and masks used in clinical and teaching experiments are mainly made of pure cotton. Can be classified and folded according to certain specifications in advance, put the surgical cap and mask into the folded surgical gown, and then wrap it with a large piece of cloth for disinfection. Generally speaking, these articles are sterilized by high pressure steam. Under the condition of 126.6℃, it can be sterilized for not less than 30 minutes, which can completely meet the sterilization requirements. When there is no autoclave, the flowing steam sterilization method can also be used (using an ordinary steamer, it will be sterilized after1~ 2 hours from the time when the water boils and releases a lot of steam).
Disinfected items are wrapped with cloth, and small scattered items can be put into storage tanks or wrapped with small cloth. The storage tank is a special container made of metal material (see figure 1- 1). Before sterilization, completely open the bottom window and side window of the storage tank. Close the bottom window and side window immediately when they are taken out of the pressure cooker after disinfection. When the storage tank is closed, it can ensure sterility within one week. Recycled items should be washed without coats or other dirt, and then folded according to different specifications, and can be reused after disinfection.
Sewing material
Sutures can be sterilized by high-pressure steam in storage tanks, surgical towels and surgical gowns.
(2) Sterilization and disinfection methods
Common sterilization methods include boiling sterilization, high-pressure steam sterilization and chemical disinfection. In addition, there are flowing steam sterilization, dry heat sterilization and flame combustion sterilization, but they are rarely used.
1. disinfection method
Before disinfection, check the practicability of the instruments and articles used to ensure that the knives and scissors are sharp, the rotating shaft is flexible, all kinds of pliers and tweezers are tightly closed, and the locks are flexible to open and close. After cleaning the instruments and articles to be sterilized, wipe them with gauze, and then wrap them with gauze or put them into a covered container for sterilization.
( 1)
Boiling Sterilization The boiling sterilization method can be carried out by general aluminum lunch boxes with lids, aluminum pot, iron pans, etc. Put the instruments to be sterilized into the sterilization container in turn, add water until all instruments are immersed, and then heat, boil and sterilize. Heating and boiling 15~20min can kill common bacteria, but it can't kill bacterial spores with tenacious resistance. Instruments or articles suspected of contaminating bacteria (tetanus, anthrax, necrotic bacteria, etc.). ) Be sure to cook for more than 90min. Adding sodium bicarbonate to ordinary water to make it into a 2% alkaline solution can raise the boiling point of water to 102~ 105℃, which can not only strengthen the sterilization effect, but also prevent metal instruments from rusting (but harmful to rubber products). The plateau air pressure is low and the boiling point of water is low, so the boiling time should be appropriately extended. In general, the sterilization time should be extended for 2 minutes every 300 meters above sea level. In order to save time and ensure sterilization quality, pressure cooker can be used for boiling sterilization. The pressure of the pressure cooker can reach 1.3kg/cm2, and the water temperature in the cooker can reach about 124℃, and sterilization can be realized in 10min.
Boiling sterilization method is suitable for sterilization of heat-resistant and moisture-resistant articles, such as metal, glass and rubber.
(2)
High pressure steam sterilization is the most widely used, safe and reliable sterilization method in surgery. High pressure steam sterilizers are portable, vertical and horizontal, with different capacities. The principle of sterilization is to use the accumulation of steam in the container to generate pressure. With the increase of steam pressure, the temperature also increases. When the steam pressure reaches 0. 1~0. 137MPa, the temperature can reach 12 1~ 126℃ for 30min, which can not only kill all bacteria, but also kill bacterial spores with tenacious resistance, thus achieving the purpose of complete sterilization. Articles sterilized in this way can be used within two weeks.
The disinfection method is as follows: firstly, tap water is added to the autoclave to the designated position, then the prepared surgical instruments are wrapped with disinfection towels and put into the container barrels of the autoclave in turn, then the container barrels are put into the autoclave, the lid is covered and the screws are tightened. When heating to a pressure of 0.0343MPa and a temperature of 108.4℃, open the air valve to release cold air, then close the air valve, and continue heating to a pressure of 0. 1029MPa and a temperature of 12 1.3℃ for 30 minutes. Then stop heating, deflate until the barometer pointer reaches 0, and then open the upper cover to take out the sterilized items for later use. This method can kill all microorganisms, including bacterial spores with tenacious resistance, and can be used to sterilize articles that can withstand high temperature and high pressure. See table 1- 1 for the time, temperature and pressure required for various articles.
Attention should be paid to the following items when autoclaving: ① The package to be sterilized should not be too big or too tight, and should generally be less than 55cm×22cm×33cm. ② The packages placed in the sterilizer should not be arranged too tightly and too densely, so as not to hinder the vapor permeation and affect the sterilization effect. ③ The sterilization effect monitoring agent should be placed in the middle of the package for monitoring, which is the most important for the operators who do not participate in sterilization operation. (4) High-pressure steam sterilization is prohibited for iodoform, benzene and other inflammable and explosive articles. ⑤ Sharp instruments, such as knives and scissors, should be disinfected carefully to avoid dullness. ⑥ Sterilized articles should be marked with time, so that they can be identified when used.
Matters needing attention in the use of autoclave: ① The autoclave pressure gauge must be accurate to ensure safe use. Regular inspection should be carried out. (2) The water added to the autoclave should not be too much, so as not to overflow the inner barrel after boiling, and the sterilized items should not be soaked in water, otherwise a certain steam pressure cannot be formed, which will affect the sterilization effect. (3) The metal hose connected to the bottom of the air release valve must be well kept and must not be damaged, otherwise the air release is insufficient, and the cold air left in the barrel will affect the temperature rise and hinder the sterilization effect. (4) After sterilization, it should be deflated intermittently and slowly immediately. When the barometer pointer reaches 0, unscrew the lid and take out the contents in time. Don't let it cool and decompress naturally, so dry items will get wet and hinder normal use. ⑤ Don't deflate too quickly after sterilization. Especially when installing glass products or other fragile items, if the decompression is too fast, the items will be seriously damaged. ⑥ The sterilization effect of autoclave should be determined frequently, and the simple method is chemical indicator method. Commercial 12 1℃ pressure steam sterilization chemical indicator card can be placed in the middle of sterilized articles. In the process of sterilization, the indicator card changes and turns black due to the influence of temperature, indicating that it meets the sterilization conditions. If it doesn't turn black, it means that it doesn't meet the sterilization conditions. Find out the reason and correct it.
(3) flowing steam sterilization (steamer sterilization) This method is only used without autoclave sterilization. When operating, put the sterilized items in the top compartment of the steamer and keep a certain distance from the boiling water to prevent excessive moisture. The time should be counted from the time when the water boils and the steam is * * * 1~2h. Usually, it is used to disinfect dressings, surgical gowns and gloves.
During steam sterilization, bacteria with spores are not easy to kill, and can only be killed by sterilization in stages, and complete sterilization can only be achieved after 2 hours * * * 3 days each time.
(4) Flame cauterization sterilization method In case of emergency, this sterilization method can be used for metal instruments. In operation, a little 95% alcohol is poured into enamel or metal utensils, and then the sterilized utensils are clamped with long tongs, and then the fire is ignited and barbecued above the flame to achieve the purpose of disinfection. Flame sterilization is very harmful to the instrument, so try not to use it in non-emergency situations.
2. Disinfection method
(1) drug immersion disinfection method For sharp instruments, endoscopes and other articles that are not suitable for thermal sterilization, chemical liquids can be used for immersion disinfection. Commonly used chemical disinfectants are as follows.
① bromogeramine and chlorhexidine: both of them are new surface-active antibacterial agents and cationic detergents, which can adsorb bacterial membranes, change their permeability, make important components in bacteria escape and play a bactericidal role. The bactericidal effect of chlorhexidine is stronger than that of bromogeramine. Both of them are soaked in 0. 1% solution, which is often used to soak blades, scissors, needles, etc. It lasts for 30 minutes. Both of them are toxic to body cells, so they should be washed with sterile saline before use. In addition, it should be noted that this cationic surfactant will fail when it comes into contact with alkali, soap, iodine, alcohol and other substances.
② Alcohol: The usual concentration is 75%. The concentration is too low, which is not enough to coagulate and denature the bacterial protein and weaken the sterilization effect. However, if the concentration is too high, the protein on the surface of bacteria will solidify too fast, which will hinder further action. Alcohol is often used for skin disinfection in surgery, which has the function of deiodination. When the sharp instrument is disinfected, it is volatile after being soaked in alcohol for 30min~lh, so it should be filtered once a week to check whether its concentration meets the requirements.
(3) Mercury chloride: The common concentration is 0. 1%~0.5%, which is used to soak cystoscope and colloid catheter for 30min. Before use, it must be washed with sterile physiological saline to prevent the toxic effect of mercury on the body.
(4) Formaldehyde: It can denature protein, not only has strong bactericidal power, but also can kill bacterial spores. But it has a strong pungent smell, which is harmful to cells. Commonly used 10% formaldehyde solution to soak plastic pipes, conduits and plexiglass. 4 ~ 6 hours, when used, rinse with sterile physiological saline.
⑤ Lysol: It can combine with bacterial protein and precipitate to kill bacteria. Insoluble in water, but soluble in soap solution, so it is made into 5% coal phenol soap solution for standby. It takes 1h to soak metal instruments, and it should be thoroughly washed with sterile physiological saline when used.
⑥ Instrument solution (antirust disinfectant): The formula is carbolic acid 20g, glycerin 266mL, 95% alcohol 26mL, sodium bicarbonate 10g, and distilled water is added to 1000mL. Soak the tax documents for 30 minutes. Precautions for disinfection with disinfectants: When using chemical disinfectants to soak instruments and articles, clean the articles before soaking, and wipe off grease (organic grease affects disinfection efficiency). All disinfected articles must be soaked in the solution. Articulated instruments (such as scissors) should open the joints; The air in the cavity bottle must be exhausted, and the inside and outside of the cavity should be soaked with disinfectant. In the middle of soaking and disinfection, if items are added, the time should be recalculated when adding items. Because most chemical disinfectants are toxic and corrosive to human body, it is necessary to wash the liquid attached to the instrument with sterile physiological saline before use, so as not to damage the tissue.
(3)
Formaldehyde steam fumigation disinfection method uses a aluminum pot with a steaming grid with a diameter of 24cm, puts a measuring cup under the steaming grid, adds 2.5g of potassium permanganate and 5ml of 40% formaldehyde, and covers tightly to fumigate for 65,438+0h, so as to achieve the disinfection purpose. If the site is large, a large fumigator can be used, and the dosage can be increased according to the above ratio.
After use, the instruments and utensils must be treated to be disinfected again for the next operation. The treatment method depends on the kind of goods, the nature and degree of pollution. Metal utensils, glass and enamel products should be cleaned after use, and special attention should be paid to the decontamination of ditches, grooves and shaft joints. Metal instruments should also be oiled to prevent rust, and rubber and plastic pipes should be washed inside. Surgical supplies exposed to certain infections should be handled specially.
(3) Precautions
(1) Because chemical disinfectants can't enter the grease and kill the bacteria in the grease, the grease on the instrument should be wiped clean before soaking.
② Chemical disinfectants are generally irritating and toxic. Therefore, instruments or articles must be washed and soaked repeatedly with sterile physiological saline or cold boiled water before use.
(3) bromogeramine and chlorhexidine dissociate into cationic active groups in aqueous solution, on the contrary, soapy water dissociates into anionic active groups in aqueous solution, and their meeting will affect their effectiveness. Therefore, all instruments and articles that have been exposed to soapy water must be washed with clean water before soaking and disinfection. In addition, contraindications are compatible with potassium permanganate and alkaline substances and should be used alone.
(4) All instruments and articles that need disinfection must be soaked in liquid medicine.
3. Preservation of aseptic items
(1) Set up a sterile goods room to store sterile goods, and all goods shall be marked with the date and name of disinfection and sterilization and the name of the executor.
(2) Autoclaved articles shall be valid for 7d, and can only be used after expiration.
(3) The validity period of boiling disinfection and chemical disinfection is 12h. After the expiration date, it must be disinfected again.
(4) The opened sterilized items can only be stored in the operating room for 24 hours.
(5) Wipe the mirror frame and floor 12 times a day in the sterile dressing room, and irradiate with ultraviolet light 12 times a day.
(6) Aseptic dressing room should have someone who is responsible for fixing, positioning and quantifying three things.
(7) Dressing instruments contaminated by specially infected animals should be disinfected twice before being put back into the sterile room.
After disinfection and sterilization, the instruments in the operating room should also be paid attention to prevent re-contamination. The delivery of sterile surgical kits and accessory kits, whether collected from the supply room or in the operating room, should be suitable for sterile carts or trays, and should not be mixed or mixed with contaminated items. Sterilization equipment stored in the operating room should be packed in double layers to prevent accidental pollution when unpacking. Small pieces of equipment should be sterilized after packaging and stored together with the packaging. The room for storing sterile instruments should be dry and dust-free, equipped with ventilation or ultraviolet disinfection devices, to minimize personnel access, and regularly cleaned and disinfected.