Beating the “Bugs”: Sterilization Is Instrumental

Instrument Decontamination and Cleaning

Blood, pus, and other secretions may contain chloride ions, which, when left to dry on surgical instruments, may cause staining, pitting, and corrosion. Instruments should be rinsed under running water within 10 minutes after use. If instruments cannot be cleaned immediately after use, they should be kept damp until they can be properly cleaned.

Gross Debris Removal

Instruments should be washed within 20 minutes after surgery with a neutral-pH or soap designed specifically for surgical instruments. High-pH  cleaners, dish soap, iodine, bleach, cold-soak solutions, chlorhexidine-based solutions, laundry detergent, and hand scrubs may cause spotting and corrosion and, therefore, are not recommended. Instruments should be cleaned of all visible debris by hand washing before placement in an ultrasonic cleaner. It is important to use an instrument cleaning brush to remove all organic material from the jaw serrations, teeth, and hinges (box locks) of instruments.

Cannulated items (e.g., Frasier suction tips, arthroscopic trocars) should be cleaned using a three-step process: (1) flush the lumen, (2) pass a cleaning brush completely through the lumen, and (3) rinse with water.

Ultrasonic Cleaning

The use of ultrasonic cleaners is growing in popularity, predominantly due to their efficiency, effectiveness, and ease of use. Placement of instruments in an ultrasonic cleaner containing a neutral-pH solution for 10 to 20 minutes can clean instruments 16 times more effectively than hand washing alone.

In ultrasonic cleaning, high-frequency sound waves are produced by a generator located within an ultrasonic unit (a small, metal tank filled with liquid cleaning solution). A unique vibration pattern is created by alternating high and low pressures during the cleaning cycle as sound waves disperse throughout the tank. During the low-pressure stage, millions of tiny bubbles form cavities in a process called cavitation. During the high-pressure stage, the bubbles collapse or implode, releasing enormous amounts of energy. The bubbles contact all surfaces, cracks, and crevices in every direction, removing debris from the objects being cleaned.

A well-mixed, neutral-pH ultrasonic cleaning solution should always be used to avoid increased surface tension and to optimize cavitation. To ensure removal of all air bubbles, freshly made ultrasonic cleaning solutions should be degassed by operating the ultrasonic cleaner for 10 minutes immediately after each new batch of cleaning solution is made and before instruments are introduced. Instruments should be placed in the ultrasonic cleaner with ratchets and box locks fully opened and exposed to maximize cleaning. The ultrasonic cleaner should not be overloaded. To prevent cross-plating, instruments composed of different metals should not be included in the same cleaning cycle. Instruments should be thoroughly rinsed when removed from the ultrasonic cleaner. It may be advisable to rinse instruments in distilled water because tap water can contain a high concentration of minerals that contribute to staining.

In general, heated ultrasonic cleaning solutions have not measurably improved cleaning results or times. Therefore, a heated tank feature is not imperative for purchasing an ultrasonic cleaner.

Ultrasonic cleaning solutions should be changed daily, or sooner if the solution appears cloudy or dirty.

Lubrication

After surgical instruments have been thoroughly cleaned and dried, they should be lubricated. Proper lubrication of surgical instruments helps prevent damage due to rubbing and scraping and  minimizes dulling and staining. All surgical instruments with moving parts (e.g., joints, box locks, ratchets, screws) should be lubricated. All moving parts should be lubricated before autoclaving, and only lubricants approved for steam sterilization should be used. The use of lubricant sprays may be preferable to lubricant baths because the latter may contain bacteria from previously dipped instruments. Furthermore, lubricant sprays can be less expensive and usually require less counter space than most bath solutions.