Positive Spore Test After Loads Were Released
On Monday at 8:00 a.m., the office manager hands you the results of the biological indicator run on Friday: positive for Geobacillus stearothermophilus spores. The practice has one Class B autoclave. The sterilization log shows three loads were processed Friday and Saturday, totaling 22 pouches, and all were released for use. Instruments from those loads were used on four patients Friday afternoon and two patients Saturday morning. You also find that the chamber drain screen was clogged with debris and the door gasket, replaced two weeks ago, is not seated properly. The dentist is out of town until Wednesday, the hygienist has a full schedule, and there is no backup sterilizer in the office. The practice manager asks you what must happen before any instrument is used today.
1. What are your first actions regarding the sterilizer and the instruments processed since the last negative biological indicator?
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Stop using the autoclave immediately and label it 'Do not use - biological indicator failure.' Quarantine every instrument pouch processed since the last documented negative biological indicator, which here means all three loads from Friday and Saturday, whether or not they were already released. Do not use any of those instruments on today's patients. Because there is no backup sterilizer, arrange for a loaner autoclave or send instruments to a local hospital or another practice for sterilization; do not substitute chemical disinfection for sterilization of critical items. Retrieve any unused pouches from drawers and stockroom shelves. For instruments already used on patients, the risk is low but not zero; follow the office's exposure-control policy and notify the dentist and practice manager so that a decision about patient notification can be made by the clinician or risk manager, not by the assistant alone.
2. Which items from the affected loads can be reprocessed, and which must be discarded? How do you decide?
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Items are reprocessed only if they are heat-stable, cleanable, and intended for reuse. Stainless-steel hand instruments, mirrors, explorers, and reusable trays can be cleaned, packaged, and sterilized once the sterilizer passes a biological indicator. Single-use items - disposable prophylaxis angles, plastic impression trays, needles, and anything labeled single-use - must be discarded even if they were in the load, because they cannot be reliably cleaned or re-sterilized. Items that were used on patients and are now contaminated with blood or saliva should be handled as contaminated; if they are reusable, they go through the normal cleaning and sterilization cycle after the autoclave is repaired. Hinged instruments should be opened, and lumen devices flushed. If an item's manufacturer instructions do not include a sterilization cycle, it is discarded.
3. What documentation and follow-up steps are required before the autoclave returns to service?
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Document the positive biological indicator, the load numbers and dates, the items quarantined, the mechanical problems found (clogged drain screen and improperly seated gasket), the corrective action, and the date the sterilizer is returned to service. Perform the manufacturer's recommended maintenance, then run a biological indicator with a control; the sterilizer cannot be used until the BI is negative. Also review chemical indicator results and the log for the affected loads, and retrain staff on loading, drain-screen cleaning, and gasket seating. Record the recall and reprocessing of instruments. The practice manager and dentist should review the policy for releasing loads before BI results are available, and consider a backup sterilization method. Keep the failed BI and control results in the maintenance file.