Overview: Water that is safe to drink may not be appropriate for processing surgical instruments. Tap water may contain toxins, hazardous chemicals, hard water ions and microorganisms. Even treated water can be a concern when it is not pure. Water treated by softening contains saline (salt) which is corrosive to surgical devices, especially for items sterilized in low temperature hydrogen peroxide sterilizers. Deionized water does not remove all minerals nor is it effective for removal of microorganisms.
Water is a critical element for surgical instrument decontamination. It is the universal solvent and the raw material used for producing instrument chemistries for medical device reprocessing and patient care. And, for removing those chemistries when they have done their jobs.
The purpose of cleaning and rinsing is to remove all visible debris from an item and to reduce the number of particulates, microorganisms, and potential pyrogens. Any organic material or residual cleaning agents remaining on an item can inactivate chemical disinfectants or sterilants as well as protect microorganisms from destruction. (ANSI/AAMI ST79 7.5.1)
Directions for Use: Water works in conjunction with the proper detergents, which may include enzymes, to loosen, lift, and remove contamination from surgical instruments. Poor water quality can inactivate detergents and lead to substandard results. Contaminants can also cause damage to instruments.
Surfactants in detergents serve an important role. They place themselves between the liquid (detergent wash water) and the solid (the soil), surround it, dislodge the soil, and bring it into suspension. Once the soil is in suspension, a thorough rinsing, for the time indicated in the manufacturers’ instructions for use for the detergent, surgical instrument, and/or automated washer, is required to remove all the soil and detergent. Enzymatic detergents contain surfactants, high purity water and one or more enzymes that breakdown soil, so they can be washed away.
Rinsing occurs at various stages in the decontamination process. Inadequate rinsing allows contaminants to resettle on the surgical instruments, placing sterile processing staff and patients at risk and jeopardizing the effectiveness of subsequent processing steps. Rinsing with water should follow each cleaning step and critical water is required for the final rinse step.
Storage Conditions: Water systems can become contaminated with microorganisms. Facilities should conduct regular maintenance and ongoing water quality monitoring to ensure water systems are performing to standards and to prevent adverse patient safety effects.
Compatibility and Safety: Surgical instrument cleaning requires high purity, low endotoxin water. Critical water is extensively treated, usually by a multistep treatment process. Distilled water and water treated by reverse osmosis is critical water.
The Association for the Advancement of Medical Instrumentation (AAMI) and the Association of periOperative Registered Nurses (AORN) recommend using critical water in the final cleaning step (see AAMI TIR34:2007).
Caution: While water is of critical importance for cleaning and decontamination, final disinfection or sterilization should produce a completely dry product that is safe for positive patient outcomes.
Moisture creates the perfect environment for microorganisms to flourish. Microorganism survival from processing errors and regrowth due to retained moisture creates increased risk of healthcare associated infections. No amount of residual moisture is acceptable when patient safety is on the line.