1. Preparation for disinfections and cleaning.
Apart from the technical and value-retention aspects involved, there is another dimension that is of particular importance when disinfected soiled/contaminated instruments: the prevention of health risks to the staff. The guidelines issued by the Robert-Koch-Institut clearly sate: “Whenever possible, instruments should be disinfected and cleaned immediately after use. Dirt residues should not be left to dry on the instruments, as this would make subsequent cleaning even harder. If necessary, instruments should be disassembled to such an extent that all surfaces can be easily reached by the disinfectant. “Unused instruments must be treated in the same way as used instruments, i-e, they must be opened or disassembled.
In either case, however, instruments should never be stored dirty over an extended period of time (e.g. overnight or over the weekend), as this would greatly increase the risk of corrosion.
Handles and cables for HF surgery are to be treated in the same way as surgical instruments.
Microsurgical instruments require special preparation techniques, so they have to be stored on racks or in suitable holding devices.
Dental materials adhering to dental instruments (such as filling materials) must be removed immediately. Otherwise, the material will harden on the instrument and/or cause corrosion.
As Far as possible, all component parts of surgical motors must be disassembled immediately after use, following the manufacturers instructions. The surfaces of components that cannot be cleaned and sterilized in the usual way should either be wiped with a lint-free cloth saturate with a disinfecting and cleaning agent or sprayed with a disinfecting spray in order to prevent gluing and encrustation.
Simple tools can be treated for reuse in the same way as surgical instruments.
Hose/tubing sets used for cooling liquids or spray nozzles must be rinsed with water from the rinsing
bottle immediately after disconnection and must then be checked for leaks (visual check, see “Inspection”).
MIS instruments and rigid endoscopes must be disassembled in accordance with the manufacturers instructions prior to preparation. Lenses and optical systems must be stored in special containers. Single-use articles must be discarded!
Dried-on residues are a particularly critical point with respect to surgical endoscopy instruments, as they are difficult to remove from small lumens and may impair the proper functioning of joints. These instruments should be treated immediately after use. In the case of HF instruments, a 3% hydrogen peroxide solution is recommended for removing any coagulated tissue particles still adhering to the instruments after extended operations.
To avoid damage, MIS instruments should always be transported in containers or holders specially designed for this purpose.
Such items should therefore always be disassembled before treating them for reuse.
I the case of flexible endoscopes, the insertion part must be wiped with a lint-free cloth immediately after use. This cloth should be saturated with an instrument disinfecting solution containing either a suitable
Detergent or a specially added cleaning booster compatible with the disinfectant in question
To avoid encrustation and clogging, the suction dust as well as other channels should be rinsed with the same solution. To rinse the air/water channel, water from the rinsing bottle can be used.
Before entering the next stage of the preparation process, a leak test must first be carried out in accordance with the manufacturers instructions. This ensures the early detection of leaks and perforations and the prevention of more serious damage like the one caused by penetrating liquids.
A defective endoscope must be returned to the manufacturer immediately, together with a description of the problem.
Endoscope cleaning and disinfections should preferably be performed on a mechanical basis, using special automatic machines.
Elastic instruments and respiration systems must always be taken apart in accordance with the manufacturers instructions before treating them for reuse. Be sure to handle cones, sealing surfaces, threaded connections and value plates carefully, protecting them against mechanical damage.
Prior to preparation, absorbers must be checked for respiration deposit (“breathing lime deposited”). Any such residues found must be completely removed.
Sensors/pickups may only be treated for reuse in accordance with the manufacturers instructions.
2. Manual disinfcetion and cleaning.
For manual preparation, the instruments must be immersed in a combined cleaning and disinfecting solution of proven disinfecting effectiveness. When using such products, the manufacturers instructions regarding concentration, temperature and exposure time must always be strictly observed. When treating non-stainless-steel instruments, be sure to check that the materials involved. Use fresh disinfecting and cleaning solutions every day, because if the same solution is used too long, the following problems may occur:
-risk of corrosion due to dirt accumulation.
Be sure to always rinse the instruments thoroughly under running water after chemical cleaning and disinfection. Rubber and elastic plastic materials need to be rinsed particularly carefully. Undissolved residues must be removed manually (be careful; do not use metal brushes or scouring agents!). To avoid water spots, a final rinse with demineralized water is recommended, Subsequently, the instruments must be dried immediately.
If the instruments are not sterilized but disinfected chemically following manual cleaning, then a separate disinfecting solution must be used. Subsequently, rinse the instruments thoroughly with sterile deminiralized water until all residues have been removed, then dry them immediately. If compressed air is used for drying. Pass it through a sterile filter.
Microsurgical instruments are easily damaged by mechanical impact.Such damage is often caused by:
For cleaning, use a lint-free soft cloth, a plastic brush or a cleaning gun. A compressed-air gun is a particularly gentle and effective way of drying and should therefore be the preferred method.
Dental instruments can usually be treated like surgical instruments. In some cases, however, special treatment is required.Hand pieces, elbows and turbines may not be immersed in a cleaning bath. All external surfaces should either be wiped with a cloth or sprayed with a suitable disinfectant. For internal cleaning and care, be sure to use the cleaning and disinfecting methods and agents specified by the instruments manufacturer.Rotating dental instruments may only be immersed in special disinfecting and cleaning solutions, due to the material used in their construction. To avoid corrosion, these instruments must be dried immediately after a short rinse and must Then be treated with a sterilization-suitable anticorrosive agent. In the case of ceramic or plastic-bonded grinding tools, it is essential to check whether the disinfecting and cleaning agents to be used are compatible with such instruments. Unsuitable agents may destroy the bonding materials (including those used for shaft fixation).
The external surfaces of the various components of surgical motor systems must be wiped with a lint-free cloth saturated with a cleaning and disinfecting solution. Soft brushes can be used. After applying a disinfecting spray, be sure to wipe the surfaces dry with a cloth. Never immerse such components in water or other liquids. Any liquid that may have entered must be removed immediately by turning the respective opening downwards.
Simple tools can be treated in the same way as surgical instruments.
MIS instruments and rigid endoscopes incorporate cavities and channels that are difficult to clean. Proper cleaning and preparation for reuse requires.
-removing all seals/gaskets.
MIS instruments and rigid endoscopes are easily damaged by mechanical impact. In the manual cleaning, e.g. when removing blood encrustations, there is consequently a risk of impairing the proper functioning of the instrument by incorrect handling. Damaged may, for example, be caused by:
To avoid damage caused by the use of unsuitable cleaning accessories, plastic brushes, cleaning guns or soft, lint-free cloths should be used for drying. Using a compressed-air gun is a particularly gentle and effective way of drying and should therefore be the preferred method.
When immersing MIS instruments or endoscopes in a cleaning and disinfecting solution, make sure that all cavities are free air bubbles (e.g. by turning or rotating the instrument or holding it aslant) so that all surfaces are freely accessible to, and completely covered by, the solution.
Note: instruments which cannot be disassembled but incorporate a rinsing connector should be rinsing thoroughly with a cleaning/disinfecting solution
Ensure that enough liquid passes through the entire instrument down to the distal end.
Dirty windows or glass surfaces should be cleaned by rubbing them gently with a swab (use wooden applications only) saturated with alcohol. If this does not work, use a neutral detergent (manual washing-up agent).
Instruments encrusted with tenacious HF coagulation that could not be removed even by intensive cleaning (e.g. with a brush or ultrasonic treatment) must be sorted out because their proper functioning is no longer guaranteed.
Regarding flexible endoscopes, all valves and caps must be removed before starting the preparation process, to make sure that all channels/dust can be thoroughly flushed and cleaned. For cleaning, immerse the endoscope in an instrument cleaning and disinfecting bath, wiping its exterior thoroughly.
The channels must first be cleaned with the brush contained in the instrument set, then rinse them with the cleaning solution. For this purpose, some manufacturers offer a hand pump. The distal end must be cleaned with special care (optical system, Albarran lever, etc.).
Immediately after this pretreatment, the instrument must be thoroughly rinsed with water both internally (channel system) and externally. Subsequently, put the flexible endoscopes into the instrument-disinfecting bath, making sure that all channels are completely filled with the solution. You may use a hand pump for this purpose. Be sure that the suction dusts are also disinfected properly. The exposure time and concentration specified by the manufacturer must be strictly observed.
After chemical disinfections, all external surfaces and channels must be thoroughly rinsed until no residues are left. To avoid water spots, use deminiralized water. Additional sterile filtration of the water prevents unwanted recontamination.
Dry all external surfaces of the flexible endoscope with a lint-free cloth. Channel drying should be always being done following the manufacturer’s instructions, using either a hand pump and a suction pump or compressed air (max. 0.5 bar). Unwanted recontamination can be prevented using filtered, sterile compressed air.
Elastic instruments with lockable cavities (such as balloons and respiratory masks) must be cleaned and disinfected in closed condition in order to keep the cavities free from liquid.
If the instruments are not sterilized but disinfected chemically after manual preparation, then a special disinfecting solution has to be used. Subsequently, the instruments must be rinsed with sterile, deminiralized water to such an extent that they are completely residue-free and then dried immediately. If compressed air is used for drying, be sure to sterilize the air by passing it through a sterile filter.
White spots can appear on elastic instruments made of plastic or rubber, simply due to water absorption. Such spots can be removed only by drying.
To avoid damaging the diaphragms and functional parts of respiration systems, no compresses air should be used for drying.
3. Machine disinfcetion and cleaning.
Cleaning and disinfecting processes can best be standardized on a mechanical basis. Always keep in mind that proper cleaning, as an integral part of the whole preparation process, is essential also for retaining the value of your instruments. Machine preparation normally requires dry discharge, since wet discharge carries the risk of proteins attaching themselves to the instruments. For this reason, a combined cleaning and disinfecting agent should always be used. When these agents lack a foam inhibitor, thoroughly rinse the instruments because any foam produced during mechanical cleaning and disinfcetion may impair results. This also applies to the special cases of heavily soiled instruments (encrusted HF instruments, filling-material residues on dental instruments, etc.), which have been pre-treated by immersion with or without ultrasound treatment.From the viewpoint of general prophylaxis, cleaning-optimized processes and procedures with separate cleaning and disinfecting stages are to be preferred.For mechanical preparation, both thermal and chemothermal processes are available for cleaning and disinfecting. In thermal processes, disinfcetion is carried out at 80 c or higher, with corresponding exposure time. Chemothermal disinfcetion processes take place at a maximum temperature of 65 C, with an added machine-type disinfectant (concentration and exposure time as specified). If the instruments to be treated allow it, thermal processes should be used.The structure of the program used depends on general hygiene requirements, the type of instruments to be treated and the quality of the water used.
Neutral-Ph products with or without enzymes as well as alkaline products can be used as cleaning agents.
When using chemical cleaning agents, the manufacturer’s instructions regarding concentration, working temperature and exposure time must be strictly observed in order to achieve optimum cleaning results while making sure, at the same time, that the instruments are treated as gently as possible. If automatic liquid dosing systems are used, these must be controllable. Where specific regulations (epidemiological or the like) require a combined thermal cleaning and disinfcetion process, alkaline cleaners are to be preferred.If chloride concentrations are rather high, the danger of pitting corrosion exists, which can be prevented with alkaline products in the cleaning cycle and by using deminiralized water for the final rinse.
for treating heat-sensitive instruments/materials, chemothermal processes are employed, which means that after cleaning a special disinfectant suitable for use in washer-disinfectors is used. In this case, the final rinse must be carried out at a relatively low temperature. Moreover, it is important to ensure sufficient drying.
1st intermediate rinse
With warm or cold water, no additives.
Adding an acidic neutralizer facilitates the removal of alkaline detergent residues. Even if a neutral cleaning agent used, it may be advisable to add an acidic neutralizer in order to prevent coating (e.g. in cases where the water used has a high salt content).
2nd intermediate rinse
Thermal disinfcetion / final rinse.
Thermal disinfcetion takes place at temperatures of 80-93 C and appropriate exposure times.
Using deminiralized water prevents water spots and coating on the items to be treated.
Drying if the machine lacks a separate drying program, drying should be carried out manually or by using a separate drying cabinet.When cleaning mechanically, pay special attention to the following:
-To ensure effective machine preparation, all trays, inserts, holders etc. must be loaded correctly.
Color-anodized aluminum parts may fade as a result of mechanical cleaning thereby losing their coding function. However, if neutral pH detergents are used at lower temperatures and deminiralized water is employed for the final rinse (and also during thermal disinfcetion), then color-anodized instruments can be cleaned and disinfected together with other instruments.Treated items must be removed from the machine immediately upon completion of the cleaning program. If they are left in the closed machine, corrosion may occur. If the latent heat stored by the instruments is not enough for drying, an additional drying cycle is required.
Microsurgical instruments can be prepared mechanically, provided the instruments are safely held in place (e.g. by using racks or other suitable supports) and a suitable rinsing method is used.
Dental instruments can be treated mechanically like surgical instruments. However, the following points need to be observed.
-Probes and other easily damaged instruments must be placed on racks or special holding devices for protection.
-Hanpieces and elbows can be treated mechanically, provided a suitable preparation technique (as specified by the manufacturer) is used.
-Mouth mirrors are subject to wear. For example, silver-backed glass mirrors may become dull as a result of machine treatment, Rhodium –metallized mirrors, in contrast, are more resistant to thermal and chemical influences but are easily damaged by mechanical impact.
Components of surgical motor systems may only be treated mechanically if the manufacturer allows such a treatment in connection with special preparation techniques and holding facilities. Original tools and accessories can be treated mechanically in the same way as surgical instruments.
MIS instruments and rigid endoscopes must be disassembled for machine preparation in accordance with the manufacturer’s instructions. All seals/gaskets must be removed and all cocks opened.
Use the mechanical preparation only if the manufacturer of the respective component has approved it. To avoid damage, fix the parts securely in place. Mechanical cleaning and disinfecting is permitted only as long as a compatible and proven technique is used. Moreover, the machine and machine inserts employed must allow hollow instruments to be sufficiently and reliably rinsed internally as well.
Instruments with tenacious coagulation residues that cannot be removed even by intensive cleaning (e.g. with a brush or ultrasonic treatment) must be sorted out discarded because their proper functioning is no longer guaranteed.
Flexible endoscopes may only be treated mechanically if special automatic machines are used. Standard washer-disinfectors are not suitable for this purpose. If endoscopes are pretreated manually prior to machine preparation, all products/detergents used must be compatible with each other. This prevents poor cleaning results as well as endoscopes surfaces changes and excessive foaming inside the machine.
Prior to mechanical preparation, a leak test must be carried out in accordance with the manufacturer’s instructions. This ensures the early detection of leaks and perforations in order to avoid more serious damage (e.g. caused by penetrating liquids). Some machines carry out a leak test automatically (either before the program starts or while it is running). Defective endoscopes must be returned to the manufacturer, together with a description of the problem.
Since the alkaline cleaning agents may damage endoscope, use only special detergents and disinfectants suitable for the mechanical treatment of flexible endoscopes. The maximum temperature of 60 C may never be exceeded throughout the cleaning and disinfecting cycles. Moreover, the instructions provided by the endoscopes manufacturer must be duly observed.
During the mechanical preparation process, the endoscope must be securely kept in place inside the machine. Use appropriate equipment to ensure that all external surfaces as well as the inside of all channels/ducts are thoroughly and reliably cleaned and rinsed.
For the final rinse, deminiralized water should be used to prevent the formation of water stains. Moreover, suitable technical processes must be employed to ensure that the water used for the final rinse is of a quality that prevents the germs growth on disinfected/sterile endoscopes.
Prior to storing the endoscope for later use, dry it properly so that the growth of microorganisms is prevented. Drying can be done in an automatic cleaning and disinfecting machine or by using a suitable drying cabinet.
Elastic instruments with lockable cavities (such as balloons, respiratory masks etc.) must be cleaned and disinfected in closed state so no liquid enters the cavities.
To prevent the mask bulge from being overstretched, discharge some of the air prior to preparation (remove the plug, squeeze out some air, then replace the plug).
Elastic (e.g. PVC) instruments with a low temperature resistance may only be disinfected, cleaned and dried at temperatures not exceeding 65 C.
Be careful with rubber instruments because detergent or disinfectant residues can cause irreversible damage during subsequent drying or sterilization, due to the fact that the surface of the material may depolymerize and turn sticky as a result. Latex coatings tend to blister off.
Residues adhering to functional parts of respiration systems are particularly damaging. Moreover, all such parts must be completely dry, as even very small amounts of moisture may cause malfunction.
Elastic instruments must never be dried at temperatures above 95 C because higher temperatures greatly reduce their useful life. The recommended temperature range is 70-80 C.
Functional parts of respiration systems of anesthesia devices vary from one manufacturer to another, so their preparation must be performed according to the manufacturer’s instructions in each case.
4. Ultrasonic treatment.
Ultrasonic treatment is a very good choice for cleaning stainless-steel instruments. Instruments sensitive to mechanical impact (e.g. microsurgical instruments, dental instruments) can likewise be gently and thoroughly cleaned with the help of ultrasound. Efficient ultrasonic devices/plants are able to dissolve encrustations even in places that are difficult to access.
Ultrasonic treatment is used.
-as an effective mechanical method supporting manual cleaning processes.
-for treating tenacious encrustations before or after mechanical preparation.
-in specially designed, optionally available component parts of automatic multi-chamber clocked cleaning systems.
To achieve optimum cleaning results, observe the following:
-Fill the bath following the manufacturer’s instructions;
-add a suitable cleaning agent or a combined cleaning and disinfecting agent;
-when using disinfectants and cleaning agents, the concentration, temperature and ultrasound treatment time (I-e, exposure time) must be matched in accordance with the manufacturer’s instructions;
-We recommend using warm water for the bath because water temperatures above 40 C facilitate degassing, thus enhancing the cleaning results;
-When a suitable detergent is used according to instructions, it will prevent protein coagulation even at higher temperatures.
Apart from a properly bath, the following basic rules should be observed in order to ensure good cleaning results:
-The items to be treated must be fully immersed in the cleaning solution.
-Hinged instruments (e.g. scissors) must remain open during treatment.
-Use only those trays that do not obstruct the ultrasonic treatment process (e.g. wire trays).
-Large-surface, bulky instruments such as hands or kidney-shaped bowls must be stored in such a way that they do not create “shadow” or anechoic zones. Position such items either vertically or put them on top pf the others.
-Do not overload trays.
-Renew the ultrasonic bath daily.
As high dirt concentration in the ultrasonic bath reduces the effectiveness of the cleaning process and increase the risk of corrosion. It may be advisable renew the bath even more frequently depending on the conditions of use.
-Where efficient plants are used, ultrasonic treatment times of approx. 3 minutes at frequencies of around 35 kHz should be sufficient.
-If disinfcetion and cleaning are carried out simultaneously, be sure to use compatible products, paying due attention to concentration and exposure time requirements.
Following ultrasonic treatment, the instruments must either be thoroughly rinsed manually or treated mechanically. The manual rinse must be carried out with drinking water, taking care that all cleaning agent and disinfectant residues are completely removed in the process. To avoid water spots, it is of course also possible to use deminiralized water for the rinse.
The instruments should then be oughly dried.
Microsurgical instruments must be stored on special racks in order to prevent damage.
To keep the surfaces and soldering joints of dental instruments intact, no acid cement remover may be added t the ultrasonic bath.
Hanpieces, elbows and turbines should never be placed in an ultrasonic bath.
Due to the materials used in their construction, rotating dental instruments must be treated with special disinfecting and cleaning agents. Prior to ultrasonic treatment,
they should be placed on special racks to avoid contact damage among the instruments (e.g. by sharp cutting edges or diamond grains). After a quick rinse under running water followed by immediate drying, be sure to treat rotating dental instruments with a sterilization-suitable anticorrosive agent.
Mouth mirrors may be adversely affected by ultrasonic treatment.
With the exception of simple tools and accessories, components of motor systems should never be treated in an ultrasonic bath.
In the case of MIS instruments and rigid endoscopes, ultrasonic-bath treatment is allowed only for those parts for hich the manufacturer has given his explicit approval (optical systems, for example, are generally excluded).
If instruments have been soiled by HF coagulation residues to such an extent that they are still not 100 % clean after intensive cleaning, they must be withdrawn from use because their proper functioning can no longer be guaranteed.
Flexible endoscopes must never be treated in an ultrasonic bath. However their accessories (such as valves, caps, biting rings or pincers) can be treated in this way.
Elastic instruments are not suitable for ultrasonic waves have no effect on them.
Functional parts of respiration systems may not be prepared in an ultrasonic bath either.
5. Maintenance and care.
Instruments with a joint or lock (such as clamps, scissors, etc.) need to be treated with an autoclavable, paraffin oil-based lubricant that complies with current pharmacopeial regulations.
These lubricants prevent metal-on-metal friction, thus ensuring ease of movement and avoiding fretting corrosion. Moreover, the regular application of such an oil prevents the joints from “sticking together: due to gumming (as might be the case when the wrong oils are used).
As a rule, it is necessary to carefully lubricate all threads, joints etc. manually and with precision each time the instrument is treated for reuse. In other words, it is not sufficient just to spray the whole instrument with oil or to apply a lubricant mechanically during the final rinse cycle.
Dental instruments are to be treated like surgical instruments, with the following exceptions:
-handpieces, elbows and turbines have to be treated with special agents in accordance with the manufacturer’s instructions, due to their complicated internal structure.
-Immediately after drying, all rotating dental instruments (drills, cutters, burrs etc.) must be treated with an anticorrosive agent suitable for use with sterilizing media such as steam or hot air.
Motor systems must always be lubricated and maintained with agent recommended by the manufacturer. Non-sealed hand pieces need internal treatment with a special cleaning and lubricating spray.
In the case of compressed air motors (with the exception of maintenance-free types), put a few drops of special oil into the air intake duct. To facilitate the distribution of the oil inside, run the motor with compressed air for a few seconds. As proper lubrication and maintenance of the motor system is a vital factor for long-term value retention, the manufacturer’s instructions should be carefully followed.
Since MIS instruments and rigid endoscopes may incorporate components made of different materials (such as plastic or rubber), a general (manual or mechanical) application of care agents might damage
Optical systems, seals/gaskets and current-carrying parts and should therefore avoided.
Joints, threads, sliding surfaces and non-maintenance-free cocks of rigid endoscopes must be treated with a special oil or grease in accordance with the manufacturer’s instructions.
Flexible endoscopes are maintenance-free, but not the valves. These need to be treated with silicone oil each time before they are inserted into the valve housing. Never use spray (the propellant gases would damage the instruments).
As lubricants, use only suitable and grease-free gels in accordance with the manufacturer’s instructions. Agents containing Vaseline or paraffin cause rubber parts to swell or soften.
Never treat elastic instruments and respiration systems with lubricants or care agents before sterilizing them. The manufacturer specifies special care and maintenance measures where they are required.
Elastic instruments made of silicone rubber are not being treated with silicone oil because this leads to swelling, rendering them useless. For same reason, never use paraffin agents for rubber and latex instruments.
Each surgical instrument has been designed for a specific purpose. Therefore, functional tests must be designed in such a way that items that do not serve their intended purpose any longer are reliably detected. In case of doubt, the instrument manufacturer should be contacted for suitable inspection/testing methods.
After cleaning, the instruments must be macroscopically clean, I-e, free from visible protein residues and other dirt.
Surgical instruments with movable parts should be given time to cool down prior to functional inspection in order to prevent metal friction that could lead to corrosion. Before carrying out functional tests, hinged and threaded instruments should always be lubricated.
Instruments with atraumatic toothing need very careful inspection. If necessary, the toothing must be subjected to additional manual cleaning to ensure atraumatic application.
Worn, damaged or porous instruments must be stored out, since they are no longer in good working order. Likewise, corroded instruments must be discarded immediately to prevent contact corrosion on other surgical instruments.
Delicate, particularly easy-to-damage instruments need to be inspected with a magnifying glass. Subsequently, they must be stored in specially designed racks, or fixed in place by other means, in order to avoid damage during transportation.
Never store flawless surgical instruments with those whose surface is defective. Especially older instruments with a peeled-off chromium and/ or nickel coating may cause discoloration or corrosion on stainless-steel instruments. We therefore recommend sorting out such instruments or pack them separately.
Handles, cables in general and neutral-electrode cables used in HF surgery must be checked for proper functioning (loose contacts!). Discard defective parts!
Instruments in need of repair have first to be cleaned and disinfected (I-e, send them through the complete treatment cycle).
Stains found on instruments result from improper treatment. The reasons for such discolorations include:
-insufficient mechanical or manual cleaning.
-use of inadequate cleaning, disinfecting or care agents;
-failure to observe the dosage instructions for cleaning, disinfecting or care agents;
-residues from cleaning, disinfecting or care agents (so-called “carry-over”).
-Poor water quality (foreign ions such as iron or silicate);
-water-soluble residues (e.g. washing agent in wrapping cloths);
-residues contained in the sterilizing steam (exceeding the standard values for steam impurities as specified in EN 28, Appendix B);
-residues from medications, marketing pens or chemical indicators;
-procedural faults (e.g. failure to clean brad-new surgical instruments before sterilizing them).
These and other potential causes of stain formation on surgical instruments are indicative of the complexity and difficulty of the problems involved. To identify the causes of any such stains in practice, we recommend seeking expert advice. Apart from their practical experience, specialized companies also help with well-equipped laboratories in such matters.
To avoid permanent damage, instruments with tenacious surface residues must first be subjected to special treatment, depending on the cause of discolorations.
To avoid damage due to metal friction (and subsequent corrosion), never use metal brushes or metal sponges for removing stains. For further details on various discoloration and corrosion causes, see chapter 2.
Surgical motors and their accessories must be subjected to functional tests in accordance with the manufacturer’s instructions prior to sterilization.
On all compresses-air components, a leak test and a visual inspection must also be carried out in addition to the functional test. This particularly applies to compressed-air hoses and motors. For checking air intake ducts the compressed-air hose needs to be connected to the compressed-air supply. Leaks can then either be detected acoustically or checked visually by immersing the hose in water.
For checking the exhaust air duct, the compressed-air motor must also be connected to the compressed-air hose. After starting the motor, leaks can best be detected by immersing the hose in water.
Simple tools are to be checked in the same way as normal surgical instruments. To avoid transportation damage, the tools should be stored in special racks
Or fixed in place by means of suitable holding devices.
The leak test for cooling-liquid tubing sets can be done with a clamp and a large syringe filled with water. Proceed as follows: fill the tubing with water, close one end with the clamp, then apply the syringe to the other end of the tube and inject the water.
Conducting a thorough functional test can only ensure the proper functioning of MIS instruments and rigid endoscopes. To achieve this, first reassemble all disassembled instruments in accordance with the manufacturer’s instructions. After the functional check, it may be necessary to disassemble the instruments once again for sterilization.Worn parts and defective components must be replaced prior to sterilization. The insulation, in particular, should be carefully inspected for potential damage.
Instruments with tenacious coagulation encrustation on working parts must be given special manual treatment as described in chapter 2 or chapter 4. should this prove ineffective, discards/replace the items.
Optical systems should be carefully cleaned with a cotton swab saturated with alcohol (to avoid damage, use a wooden or plastic applicator, not a metallic one). If this is not enough to clean the lenses, return the component to the manufacturer for inspection.
Optical fibers and optical fibers cables must be checked for fiber breaks. To do this hold one end of the optical-fiber cable against a light source, then look into the cable at the other end. If you see little black spots, this indicates fiber breakage. Note that the more breaks there are, the lesser the light output will be. Therefore, sort out such optical fibers and endoscope parts with a defective surface.
Clouded optical systems of flexible endoscopes can normally be cleaned with a wooden or plastic applicator (do not use metal!) saturated with alcohol. If this is not enough to clean the lenses, return the component to the manufacturer for inspection.
Fiber breakage in optical waveguides can be detected by holding the proximal end against a light source and looking into the fiber at the distal end. If little black spots are seen, this indicates fiber breakage. Note that the large number of such breaks significantly lowers the light output. Such defective instruments must be returned to the manufacturer for inspection. This also applies to endoscopes with visible external defects (e.g. deformation of the insertion part or supply hose; overstretched rubber sleeve of adjustable part).
Flexible endoscopes should be stored in a safe place unfolded. Suspension has proved useful, as this facilitates drying. The adjusting wheels should be unlocked for storage. Note that the carrying case is not suitable means for storage.A comprehensive functional check must be carried out each time the endoscope is used for an operation. As lubricants, use only suitable fat-free gels following the manufacturer’s instructions. Never use Vaseline or lubricants containing paraffin, as these substances swell or soften the material.
Respiration systems must be checked for proper functioning and working conditions in accordance with the manufacturer’s instructions.Eastic instruments have always to be checked for proper functioning in accordance with the purpose for important inspections include:
-check balloon filling systems for tightness;
-check the lumens of catheters and probes for unobstructedness;
-test connectors for safely and reliability (e.g. ISO connectors);
-check the shape of the instrument (e.g. bending radius of tracheal tubes).
Never use damage or defective elastic instruments! Frequently observed defects include.
-peelings (blister formation).
To prevent premature failure, be sure to store elastic instruments in a dry place at room temperature. Do not kink or over-stretch them (use suitable connectors only).
Always sterilize the instruments in accordance with current standards (DIN, EN, ISO). This applies to the sterilization conditions as well as to the equipment to be used. In addition, the Operating Instructions provided by the manufacturer of the sterilizer used must be observed. The sterilizing accessories and packaging materials employed must be suitable for the items to be sterilized and must also be compatible with the sterilization method used. For a defined set of instruments, special measures need to be taken in order to ensure proper sterilization. Such measures are specified by the instrument manufacturer where required.
7.1 Autoclaving (steam sterilization).
Autoclaving is usually performed with saturated steam at 134 C. for articles with a limited thermostability; a temperature of 11 C may be used, combined with longer treatment/exposure time.The sterilization procedure must comply with accepted standards and be suitable for the items to be sterilized. The packing materials for the process must also comply with pertinent quality and application standards; moreover, they must be suitable for the sterilizing procedure selected.The sterilization steam must be free from impurities and should neither impair the sterilizing process nor damage the sterilizer or the items to be sterilized. To ensure this, the limited values specified in EN 285, Table 1, relating to the quality of the water fed to the boiler and the condensate must not be exceeded.
Dental instruments can usually be autoclaved in the same way as surgical instruments. Should separate treatment be required, the following instructions apply:
-Rotating dental instruments (e.g. drills or cutters/burrs) are autoclavable.-Handpieces and elbows should be autoclaved at 134 C wherever possible, due to the short exposure time.-In the case of turbines, consult the manufacturer’s instructions to determine whether or not autoclaving is permitted.-Mouth mirrors are items, which are subject to wear and will sooner or later become dull as a result of the expansion difference seen in the different materials during preparation.
All sterile-use components of surgical motor systems can be autoclaved at 134 C. be sure to observe the manufacturer’s instructions, particularly with respect to how to store these components properly and safely during sterilization.Compressed-air hoses need to be protected against mechanical damage during sterilization.
MIS instruments and rigid endoscopes can be sterilized conventionally, using suitable packaging material. Autoclavable optical systems should be sterilized at 134 C rather than at 121 C, due to the shorter exposure time (and correspondingly lower thermal stress). To avoid mechanical damage, optical systems should always be stored securely as recommended by the manufacturer.
Flexible endoscopes are not autoclavable due to their lower heat stability, so use a gas sterilizer in uses where sterilization is required. However, all endoscopically used items (such as clamps, catheters etc.) are autoclavable.
Elastic instruments (wit and without a balloon) made of a silicone elstomer and natural rubber (or latex) can be treated by autoclave. Due to the shorter thermal stress period, it is better to sterilize at 134 C. items made of thermoplastic materials (plastics), however, may only be autoclaved if such a treatment is expressly permitted by the manufacturer for example.&