Care of Your Instruments
Use instruments only for the purpose they were designed for.
Handle instruments gently - avoid bouncing, dropping or overstraining.
Soak instruments to loosen blood and soil from box locks, ratchets, hinges etc. Clean instruments immediately after use to prevent blood and other debris from drying on to the surface. Blood causes a stain which is difficult to remove, and saline solution is highly corrosive to stainless steel.
Rinse all cleaning residue thoroughly off the instrument.
Use distilled or demineralized water only for washing and rinsing as well as for sterilizing, along with a nylon brush, nylon pot scrubber and low-sudsing, near-neutral detergent (pH 7-a). Normal tap water will leave deposits on the instruments due to the high mineral content.
Do not use steel wool, wire brushes, highly abrasive cleaners or detergents with a high pH (B-9) as this will damage the passive layer or skin of your instrument. The so-called passivation process during manufacturing forms a thin protective film on the surface of the stainless steel instrument. Through constant use and repeated processing an instrument will actually passivate itself. Older instruments are well protected by a tough layer of passivation as a result of hundreds of washings, dryings and sterilizations.
Keep box locks and ratchets open when cleaning and sterilizing instruments. Disassemble all instruments with removable parts.
Immediately after cleaning dip instruments in a water-soluble lubricant such as Instrument Milk, Preplube etc. Do not rinse or wipe off - the protection film of the lubricant should remain on the instrument throughout sterilization and storage. If ultrasonic cleaning methods are used it is essential to lubricate with Instrument Milk.
Keep box locks, ratchets, hinges and serrations Free of any debris. If substances are allowed to build up in the box lock the instrument will become stiff and be subjected to misalignment and cracking.
Thoroughly dry the instruments before wrapping them. Any remaining moisture, particularly in the box locks, hinges and crevices may result in corrosion.
Make sure your reusable instrument wrappers are rinsed thoroughly to remove all residues of the detergents used for laundering, otherwise staining or corrosion might occur during steam sterilization.
Never mix stainless steel instruments with instruments of dissimilar material (carbon steel, copper, brass, aluminum). If a plated instrument is chipped or peeled an electrolytic action will carry particles from the exposed metal on to the surface of the stainless steel instrument. To eliminate problem replace all plated instruments with stainless steel, if possible.
Never put stainless steel instruments and plated instruments together in the ultrasonic cleaner, as electrolysis will cause corrosion or etching on the stainless steel instruments.
Avoid contact corrosion. Always keep stained or corroded instruments away from impeccable stainless steel instruments.
A few words on Tungsten Carbide tipped instruments:
Make sure all detergents and lubricants are pH neutral. Tungsten Carbide tips and inserts can deteriorate prematurely. Strong ALKALINE solutions (over pH 7) will attack and actually break down the tungsten particles. If your solutions turn out to be strongly ACID (below pH 7) you have found the cause for breaking down the cobalt binder which holds the tungsten and the carbon particles in position - the insert is losing its hardness.
SPOTTING, STAINING, RUST and CORROSION
Even the finest stainless steel instrument can become spotted very quickly. Mat finished instruments are more susceptible to staining than instruments with a bright or mirror finish. Adhering to proper cleaning and sterilization procedures will prevent mast occurrences of staining and spotting.
Light or dark spots
Slow evaporation of water condensation on the instrument will cause light or dark spots. Mineral deposits left behind after the water has evaporated is the result of using tap water. The use of distilled or demineralized water will eliminate the problem. Spots can also be the result of opening autoclave door before steam has been completely exhausted, which causes a slow drying process. Another cause of spotting can be traced to reusable instrument wrappers. During laundering procedures it is important that the detergents are thoroughly rinsed out. Any residues will be carried on to the instrument surface during steam sterilization.
A dull brown or blue stain usually is a simple build-up of oxidation on the surface of the instrument. That stain is more detectable on a dull (mat) finished instrument than on a bright (mirror) surface. It is the formation of chromic oxide, a very thin hard layer which forms naturally on the surface of stainless steel to prevent atmospheric corrosion.
Are usually the result from cold sterilizing solutions. Prepare the solution to exact proportions and change as directed by the manufacturer. Prolonged use will make the solution corrosive. Use of distilled or demineralized water and a rust inhibitor will minimize discoloration.
May result from contact with ammonia. Many cleaning compounds contain ammonia which remains on the Instrument if not rinsed thoroughly. Can also result from amine deposits traced in the autoclave or steam pipes. Follow autoclave cleaning with a cycle of distilled water.
It is unlikely that surgical grade stainless steel will rust. What appears as rust is actually residual organic matters or mineral deposits in box locks, ratchets, serrations, hinges etc. which have been baked on to the surface. Sterilization of stainless instruments together with plated instruments of dissimilar material should be avoided. Chipped or imperfectly plated carbon steel instruments will cause rust deposits on stainless steel instruments. Electrolytic action will carry carbon particles from the exposed metal on to the stainless steel surface. These particles promptly oxidize and the stainless steel instrument appears to have rusted. A rust-colored film on instruments can be caused by the high mineral content or by the use of water softeners.
Presence of blood and soil in box locks, ratchets, serrations, hinges etc. can cause corrosion. More care should be taken in cleaning. Excessive moisture left on the surface of the instrument can lead to corrosion. Preheat the autoclave, do not rush the drying time. Foreign matters deposited in the autoclave can result in spotting and corrosion of instruments. Inner surfaces of the autoclave should be given a routine maintenance. Wipe down with acetic acid (equal parts of vinegar and distilled water) to remove any impurities. Stress corrosion can be caused by not opening box locks during sterilization procedure. The heating-up and cooling-down process during sterilization causes tension in the material.
When instruments are exposed to saline solutions, blood, iodine, potassium chloride and other compounds pitting will occur. Instruments should be rinsed thoroughly immediately after exposure. Pitting can also be traced to detergents with a high pH level (B-9) used for instrument cleaning. Instruments should be thoroughly rinsed after cleaning. It is impossible to completely restore an instrument after pitting or rust has eroded the hard surface. The instrument should be replaced immediately as a pitted instrument is far more susceptible to further corrosion.