Positive Biological Indicator in a Load Containing Orthopedic Instrument Trays
A 132°C gravity-displacement steam sterilizer in a hospital central processing department has just completed 24-hour incubation of biological indicators for load 4471. The load contained two total knee arthroplasty instrument trays, one loaner spine tray, and four minor sets. The biological indicator is positive. Chemical indicators in all trays changed appropriately, and the sterilizer printout shows temperature and pressure within range. One knee tray was released and used 6 hours earlier; the other remains in sterile storage. The implant components came from manufacturer sterile packaging and were not reprocessed. The first patient is in the PACU. The operating room is asking to flash-sterilize a dropped femoral trial so the second case can start. The department has one other steam sterilizer available.
1. List your immediate recall and notification actions, and identify which patients and items are affected.
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A positive biological indicator means the load cannot be considered sterile, even though the chemical indicators and printout looked acceptable. Immediate actions:
- Remove the sterilizer from service and label it clearly.
- Quarantine every item from load 4471 that remains in sterile storage, including the unused knee tray, the loaner spine tray, and the minor sets.
- Identify the knee tray that was already released and used, and trace it to the patient and procedure.
- Notify the SPD manager, operating room charge nurse, surgeon, infection prevention, and risk management according to policy.
- Retrieve any load items that may have been distributed to other locations.
- Do not release any item processed in that sterilizer after the last documented negative biological indicator until the investigation is complete.
The patient who had surgery is affected because nonsterile instruments contacted an open wound, even though the implants themselves were not in the load. Notify the surgeon and infection prevention so the patient can be monitored and follow-up can be arranged per policy. Avoid telling the patient that infection has occurred; the exposure is a potential risk, not a diagnosis.
2. What must be completed before the sterilizer can return to service, and how should you handle the flash-sterilization request?
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Return to service requires more than repeating one biological indicator. Review loading, cycle selection, operator training, steam quality, and the biological indicator lot and incubation controls. The sterilizer must then pass three consecutive biological indicator cycles, with the same cycle type and test pack configuration, along with acceptable chemical and mechanical monitoring; maintenance may be required. Written clearance from SPD leadership and infection prevention should be obtained.
The flash request should not be used to bypass the problem. A dropped femoral trial must first be cleaned and decontaminated according to the manufacturer's instructions; wiping it is not sufficient. Immediate-use steam sterilization may be acceptable for a non-implant item under a validated policy when there is a genuine urgent need, but it is not a convenience substitute for a sterile backup. Use the functioning sterilizer or open a replacement sterile trial. Do not process the item in the suspect sterilizer, and do not release the unused knee tray merely because its chemical indicator changed.
3. The operating room asks, "The chemical indicator turned the right color, so can't you release the unused knee tray?" Explain why that is unsafe.
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A chemical indicator shows that the package was exposed to the expected conditions, such as temperature, moisture, or time, but it does not prove that the microbial kill was adequate. Chemical indicators can fail to detect a partially failed cycle, an overload, or a resistant organism challenge. The biological indicator is the direct check of lethality, and it was positive for this load. Because the unused knee tray was in the same chamber and load, it must be treated as nonsterile regardless of its external indicator. Release would create a false sense of security and could lead to a patient exposure. The correct decision is to quarantine, reprocess only after the sterilizer is cleared and the items are cleaned and repackaged, and document the recall.