Reusable equipment and the care environment can carry microorganisms from one client to another. Reprocessing breaks this link in the chain of infection (infectious agent → reservoir → portal of exit → mode of transmission → portal of entry → susceptible host).

Key definitions

The core difference: sterilization kills spores; disinfection does not.

Microbial resistance, from most to least resistant: prions → bacterial spores (e.g., Clostridioides difficile, Geobacillus) → mycobacteria (tuberculosis) → nonenveloped (small) viruses → fungi → vegetative bacteria → enveloped viruses (e.g., HIV, influenza).

Spaulding classification — the processing level depends on the risk of infection from the item's use.

Nurses assess before using any sterile or reprocessed item:

• Package integrity: intact, dry, no tears, holes, or stains; sealed properly
• Chemical indicator on the package has changed color
• Expiration or event-related shelf life per facility policy
• Storage conditions: clean, dry, off the floor, away from sinks and splash
• Any doubt about sterility → consider the item contaminated and do not use

Event-related sterility: a properly packaged sterile item remains sterile until an event compromises it (moisture, damage, dropping, contamination), not simply because time passes. Facilities may still assign dates. A wet package is contaminated because moisture wicks microorganisms through the wrap.

Sterilization is verified by monitoring:

Sterilization methods

Prions (e.g., Creutzfeldt-Jakob disease) resist standard sterilization; instruments from suspected cases need special reprocessing or disposal per policy.

Disinfectants

Blood and body fluid spills: wear gloves (and other PPE as needed), absorb the spill, clean, then disinfect with an EPA-registered disinfectant or freshly diluted bleach — commonly 1:100 (about 500 ppm) for small spills on nonporous surfaces, 1:10 (about 5,000 ppm) for large spills or before cleaning in labs. Follow the product's contact time.

Antiseptics for skin

• Alcohol-based chlorhexidine (more than 0.5% chlorhexidine gluconate with alcohol) is preferred for surgical site preparation and vascular catheter insertion in most adults; allow to dry completely (fire risk with alcohol in the operating room)
• Povidone-iodine is an alternative (e.g., chlorhexidine allergy, mucous membranes); needs time to dry to work; check for a prior reaction to povidone-iodine (shellfish or contrast reactions do not predict one)
• Chlorhexidine is avoided on mucous membranes, the middle ear, meninges, and in some premature infants

Older teaching named povidone-iodine as the standard skin preparation; current US guidance favors alcohol-based antiseptics, with chlorhexidine-alcohol most often used.

Listed in priority order.

1. Protect yourself: wear appropriate PPE (gloves, eye protection, gown) when cleaning and handling chemicals; ensure ventilation for glutaraldehyde and bleach
2. Clean before disinfecting or sterilizing — remove organic matter at the point of use (pre-cleaning), keep instruments moist until reprocessed
3. Match the process to the Spaulding category; single-use devices are never reprocessed on the unit
4. Check every sterile package before opening (intact, dry, indicator changed, not expired per policy)
5. Follow manufacturer instructions for dilution, contact time (the surface must stay wet for the full time), and storage of disinfectants
6. Dedicate noncritical equipment to clients on contact precautions, or clean and disinfect between clients
7. Clean the environment from clean to dirty and from high to low; use sporicidal agents (bleach) for C. difficile rooms
8. Store sterile items in closed cabinets, clean and dry, rotating stock (first in, first out)
9. Report sterilizer failures or positive biological indicators so affected loads can be recalled

• Home disinfection: use household bleach diluted according to the label with cool water; never mix bleach with other cleaners
• Clean reusable home devices (nebulizer parts, CPAP masks and tubing, glucose meters) per manufacturer instructions; air-dry completely
• Personal items such as thermometers should be cleaned with alcohol between uses and not shared when possible
• Dispose of home sharps in a puncture-resistant container (see Topic 17)

• Sterilization kills all microbes including spores; disinfection kills most pathogens but not spores
• Clean first — organic matter blocks disinfection and sterilization
• Spaulding: critical → sterilize (enters sterile tissue or blood: scalpel, urinary catheter); semicritical → high-level disinfection (mucous membranes: endoscopes); noncritical → low-level (intact skin: BP cuff, stethoscope, thermometer)
• Steam autoclave: 121 °C (250 °F) at about 15 psi (15–30 minutes) or prevacuum 132 °C for 4 minutes; preferred method
• Dry heat: 160–180 °C for 1–2 hours — powders, oils, glass, metal
• Ethylene oxide = low-temperature gas for heat-sensitive items; toxic, needs aeration
• Glutaraldehyde = HLD for endoscopes; ventilation and PPE
• Blood spills: absorb, clean, then diluted bleach (1:100 small, 1:10 large)
• Biological indicator (spore test) is the only direct test of microbial kill; chemical indicator shows exposure only
• Wet or torn sterile package = contaminated
• Skin antisepsis: alcohol-based chlorhexidine is preferred; let it dry