Sterilization is a process designed to eliminate all microbial life, including bacteria, viruses, and spores, from instruments and surfaces. This removal is important in healthcare and other settings. It prevents infections and disease transmission, ensuring patient and user safety.
The Concept of Sterility Duration
For a long time, an instrument’s sterility was determined by a fixed expiration date. This has been replaced by “event-related sterility,” meaning a packaged sterile item is considered sterile indefinitely until an event compromises its packaging integrity. This recognizes contamination is due to external factors, not time.
Organizations like AAMI and CDC support this event-related approach. They emphasize that if the sterile barrier remains intact, contents are presumed sterile. This principle helps healthcare facilities manage their inventory more efficiently and reduces the unnecessary reprocessing of instruments that are still safe for use.
Elements That Affect Sterility
External factors, or “events,” can compromise sterility. Breaches in the sterile barrier, such as tears or punctures, are a concern. Moisture contamination also poses a risk, allowing microorganisms to wick through and contaminate contents.
Environmental conditions play a role in maintaining sterility. Exposure to dust, dirt, or excessive humidity can degrade packaging materials and introduce contaminants. Extreme temperature fluctuations might also affect the integrity of packaging materials. Improper handling, such as dropping, crushing, or excessive manipulation of the packaged item, can create micro-tears or weaken seals that are not immediately visible. Storage conditions further influence sterility, with items stored in high-traffic areas, near vents, or on the floor being more susceptible to damage and contamination.
Handling and Storage Best Practices
Maintaining the sterility of packaged instruments requires adherence to specific handling and storage protocols. Instruments should be stored in clean, dry, and designated areas, away from direct sunlight, moisture, and extreme temperatures to preserve packaging integrity. Optimal storage environments often include specific temperature and humidity ranges to prevent material degradation.
Careful handling is also important to prevent damage to the sterile barrier. Minimizing manipulation of packages and avoiding dropping or crushing them helps to maintain their integrity. Before an instrument is used, a visual inspection of the package for any signs of compromise is necessary. Implementing a “First-In, First-Out” (FIFO) system for inventory rotation helps ensure that older sterile items are used before newer ones, preventing prolonged storage that could increase the risk of undetected damage, rather than indicating an expiration.
When to Re-sterilize or Discard
If there is any doubt about an instrument’s sterility, it should always be considered non-sterile. This principle prioritizes patient safety above all else. Visual inspection of the package is a necessary step, looking for tears, holes, moisture, or any discolored indicators that suggest a breach in the sterile barrier.
When a sterile package is compromised, or its sterility is questionable, specific action steps are necessary. If the item can withstand the process and the facility has the appropriate equipment, re-sterilization is an option. However, if re-sterilization is not feasible or appropriate for the instrument, it must be discarded to prevent the possibility of contamination.