Cleaning is the most important step in the instrument reprocessing cycle. An autoclave uses saturated steam under pressure to achieve sterility, but this steam cannot penetrate dried debris or organic material remaining on the instrument surface. If instruments are not thoroughly cleaned first, the remaining organic residue acts as a protective barrier, shielding microorganisms from the sterilizing agent. Effective cleaning removes both organic matter, such as blood and tissue, and inorganic residues, like salts and oxides, ensuring the instrument is visibly clean before sterilization.
Immediate Post-Use Handling and Safety
The decontamination process begins immediately after a procedure to prevent biological soil from drying. Allowing bodily fluids to dry creates a tenacious film that is difficult to remove and compromises sterilization. To address this, technicians often use specialized enzymatic foam or gel sprays designed to keep the organic material moist until the instruments can be transported to the cleaning area. These pre-treatment products contain enzymes that begin breaking down proteins and fats, which significantly aids the later cleaning stages.
Personnel handling contaminated instruments must wear appropriate Personal Protective Equipment (PPE) to protect against infectious agents and hazardous chemicals. This typically includes heavy-duty, puncture-resistant utility gloves, fluid-resistant gowns, and eye protection such as goggles or a face shield to guard against splashes or aerosols. Once initial pre-treatment is applied, instruments must be contained in a clearly labeled, sealed tray or container for safe transport to the central reprocessing area. Transporting instruments in this manner minimizes the risk of accidental staff exposure and prevents cross-contamination of other surfaces or equipment.
The practice of soaking is often employed when instruments cannot be processed immediately, but the soaking solution must be correct to avoid damaging the metal. Instruments should be submerged in water or a neutral pH enzymatic presoak solution, which actively works to loosen bioburden. Saline or tap water should not be used for prolonged soaking, as the chlorides and mineral salts in these liquids can accelerate corrosion and pitting on stainless steel instruments.
Detailed Cleaning Procedures
Cleaning involves the physical and chemical removal of all visible and non-visible soil using specialized detergents. Detergents selected are typically neutral pH (7.0 to 8.0), low-foaming, and non-corrosive, since acidic or alkaline products can damage instruments. Many manufacturers recommend enzymatic cleaners that contain a combination of enzymes like protease, lipase, and amylase, which specifically target and break down proteins, fats, and starches found in biological soil.
Manual cleaning is reserved for delicate, complex, or heavily soiled instruments, or when mechanical cleaning is unavailable. When manually cleaning, the instrument must be fully submerged beneath the water’s surface to prevent the creation of infectious aerosols. Technicians use soft-bristled brushes, never abrasive materials like steel wool, to gently scrub all surfaces, paying close attention to hinges, serrations, and lumens. Instruments with multiple parts should be disassembled before cleaning to ensure all surfaces are fully accessible to the cleaning solution.
Mechanical cleaning offers a standardized and effective method for high-volume or intricate instruments, primarily utilizing ultrasonic cleaners or washer-disinfectors. Ultrasonic cleaners work through a process called cavitation, where high-frequency sound waves create millions of microscopic bubbles in the cleaning solution. These bubbles rapidly collapse or implode, generating a powerful vacuum action that dislodges soil from hard-to-reach areas like box locks and fine serrations.
The detergent used in an ultrasonic cleaner must be low-foaming to maintain the effectiveness of the cavitation process. Washer-disinfectors operate similarly to sophisticated dishwashers, using pressurized water jets, cleaning agents, and high temperatures to clean and thermally disinfect instruments. Both mechanical methods are highly effective but must be used with instrument-specific detergents and according to the manufacturer’s prescribed cycle times.
Final Steps Before Autoclaving
Once instruments are visually clean, they must be thoroughly rinsed to remove all residual detergent, which can interfere with sterilization or cause corrosion. Rinsing should be performed using distilled or deionized water, as the minerals and ions present in tap water can leave deposits on the metal surface that lead to spotting or staining. Instruments should be rinsed while being opened and closed to flush out any trapped chemical residue from the hinges and joints.
After rinsing, instruments must be completely dried, as moisture remaining on the surface can interfere with the steam sterilization process and lead to rusting. Drying can be accomplished through a forced-air drying cycle in a washer-disinfector or by air-drying in a controlled environment. A final inspection must be performed under magnification to confirm the absence of any remaining debris, rust, or damage.
Instruments with moving parts, such as scissors, hemostats, and needle holders, require lubrication to maintain their function and prevent stiffness. Specialized instrument lubricants, often referred to as “instrument milk,” are applied after cleaning and drying. These lubricants must be water-soluble and steam-penetrable, ensuring they do not create a barrier that prevents the steam from reaching the instrument surface during autoclaving.
The final step is packaging, which involves placing the cleaned, dried, and lubricated instruments into a sterile barrier system. Packaging materials, such as paper-plastic pouches, sterilization wraps, or rigid containers, must be compatible with steam sterilization and allow for the penetration of the sterilizing agent. Instruments must be placed in the packaging in an open position and without overcrowding, ensuring the material is properly sealed to maintain sterility.