The proper care of medical instruments is a foundational step in infection control, minimizing the risk of transmitting infectious agents through contaminated objects. A rigorous process of cleaning and disinfection is the primary defense against pathogen spread, whether managing home supplies or specialized reusable devices. This sequence is crucial because visible foreign material, such as blood and tissue, can shield microorganisms from chemical disinfectants. Correctly applying these procedures ensures instruments are safe for subsequent use.
Understanding the Levels of Instrument Care
The terms used to describe instrument decontamination represent distinct levels of microbial destruction. The first step is cleaning, which is the physical removal of all visible foreign material using water, detergent, and mechanical action. This preparatory step does not kill germs, but it is necessary because organic matter can block disinfectants from reaching the surface.
Disinfection is the second level, utilizing chemical agents or heat to eliminate most pathogenic microorganisms, such as bacteria, viruses, and fungi. Disinfection, even at a high level, does not reliably destroy all bacterial spores, which are highly resistant dormant forms. For home settings, high-level disinfection is often the most practical goal, substantially reducing infection risk.
The highest level is sterilization, the complete destruction of all microbial life, including bacterial spores. In professional settings, instruments that penetrate skin require sterilization, often achieved with high-pressure steam. For the average person, high-level disinfection is the standard for reusable non-critical devices.
Initial Steps for Physical Debris Removal
Physical cleaning must be performed before applying any chemical disinfectant, as removing the organic load is essential for efficacy. Begin by donning appropriate personal protective equipment, including heavy-duty gloves and eye protection, to shield against infectious material and chemical splashes. Immediately after use, rinse instruments under cool, running water to prevent blood and tissue from drying onto the surface.
The instruments should then be soaked and scrubbed thoroughly using a detergent, such as mild dish soap or a specialized enzymatic cleaner. Enzymatic cleaners contain enzymes that break down protein and organic material, enhancing the scrubbing effectiveness. Use a soft-bristled brush to reach intricate areas like hinges, serrations, and lumens. Mechanical friction is necessary to disrupt and remove biofilm, which can protect pathogens from later disinfection.
After scrubbing, rinse the instruments completely with clean water to remove all traces of detergent or enzymatic residue. Residues can interfere with chemical disinfectants or contribute to corrosion during drying. This meticulous cleaning prevents organic material from inactivating the germ-killing agents.
Practical Disinfection Methods
Once instruments are physically clean, they are ready for the disinfection phase using heat or chemical solutions. Boiling is an accessible heat method that achieves high-level disinfection, though not sterilization. Instruments must be fully submerged in water and boiled for a minimum of 20 minutes to destroy most vegetative bacteria and viruses. This time begins only after the water reaches a rolling boil.
A 70% solution of isopropyl alcohol is a highly effective and widely available chemical option. The 70% concentration is more potent than 99% alcohol because the water slows evaporation and facilitates the denaturing of microbial proteins. Instruments should be submerged for a contact time of at least two minutes to ensure complete germicidal action. Alcohol is generally safe for metal instruments but can damage certain types of plastic, rubber, or bonded parts.
Another chemical option is a freshly prepared dilute bleach solution, using household bleach (5% to 6% sodium hypochlorite). For high-level disinfection, a 1:10 ratio (one part bleach to nine parts water) is recommended. Instruments must remain immersed for a minimum of 10 minutes to ensure adequate contact time. Immediately after the contact time, rinse instruments thoroughly, as sodium hypochlorite is highly corrosive and will quickly damage metal surfaces if left on.
Drying, Inspection, and Safe Storage
The final stage focuses on preserving the disinfected state until the next use, beginning with thorough drying. Instruments must be completely dry before storage because residual moisture encourages microbial growth and rust development. Use clean, lint-free towels to dry each instrument manually, or allow them to air dry completely on a clean, dry surface.
Once dried, inspect each instrument carefully for signs of damage or residual debris. Look closely for rust spots or any remaining organic material missed during cleaning. Also check for physical damage, such as dull blades, misaligned tips, or cracks in plastic components. Damaged instruments may not function correctly or can harbor pathogens.
Instruments must then be stored to protect them from environmental contamination. Place the clean, dry, and inspected instruments in a dedicated, clean container with a tightly fitting lid. Alternatively, wrap them in a clean, lint-free towel or a sterile pouch to create a barrier against dust. Proper storage ensures the effort put into decontamination is maintained.