Medical Device Reprocessing and Sterilization
This domain tests the full reprocessing chain - point-of-use treatment, transport, cleaning, disinfection or sterilization, inspection, packaging, sterilization monitoring, and storage - plus the parameters and limitations of each modality. Expect scenario items on cycle selection, packaging, and load release.
Core rules
- Cleaning always precedes disinfection or sterilization; organic soil protects microorganisms and inactivates chemical sterilants.
- Steam is the default for heat- and moisture-tolerant items. Prevacuum cycles typically run 132–134 °C for about 3–4 minutes plus dry time; gravity cycles are longer. Immediate-use (formerly flash) sterilization is for urgent items only and is not a storage method; implants need documented justification.
- Low-temperature options include ethylene oxide, hydrogen peroxide gas plasma, and vaporized hydrogen peroxide; each has its own aeration, packaging, and material-compatibility rules.
- Monitor every load with physical parameters, a chemical indicator inside the package, and a process challenge device. Biological indicators use Geobacillus stearothermophilus for steam and hydrogen peroxide, and Bacillus atrophaeus for ethylene oxide and dry heat.
- The Bowie-Dick test checks air removal and steam penetration in prevacuum sterilizers; it is not a sterility test.
- Sterile items stay sterile only if packaging is intact and storage is clean, dry, and temperature-controlled.
Worked example
A prevacuum steam load at 134 °C for 4 minutes shows a positive biological indicator. Reasoning: the load is non-sterile. Quarantine it, recall every item processed since the last negative BI in that sterilizer, notify infection prevention, review the cycle record, packaging, and loading pattern, then retest before returning the unit to service.
Traps that cost marks
Sterilization does not clean. Overloading, overpacking, or using the wrong pouch for the cycle causes failures. Chemical indicators show exposure, not sterility. Never release a load on physical parameters alone when a BI is indicated.