Positive biological indicator in the CSSD after the load has already been released
A 320-bed regional hospital. The CSSD runs two 300-litre horizontal steam sterilizers at 134 °C, 2.1 bar, 4 minutes. On Monday the morning load contained 63 wrapped sets, including 8 minor surgical trays and 4 hollow-instrument sets. The Bowie–Dick test passed, the external and internal chemical indicators turned the correct colour, and the load was released at 08:40 and sent to the operating theatre. At 09:15 on Wednesday the rapid-readout biological indicator from that same load (Geobacillus stearothermophilus) is read as positive. By then 21 of the 63 sets have been used: 9 in elective hernia and gallbladder operations, 12 in dressing-room procedures. The sterilizer has been reloaded and is running again. The head of the surgical department says the positive result is 'probably a lab error' and asks the nurse in charge of the CSSD to release the current load and not to inform management until the week is over.
1. What do you do in the first hour - with the running sterilizer and with the Monday load?
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The governing principle: a positive biological indicator means the cycle can no longer be assumed to have achieved sterility assurance. A passing chemical indicator does not override it, because chemical indicators show that the package was exposed to the parameters, not that the microbial kill was achieved.
- Stop the running cycle. Remove the current load and quarantine it - do not release it, do not return it to the shelves. Label it 'quarantine - not sterile' with the date and the sterilizer number.
- Take the sterilizer out of service: tag it, record the time, and note the last qualifying cycle.
- Inform the head of the CSSD, the hospital epidemiologist and the deputy chief physician for the medical part in writing, today. Not on Monday.
- Recall every set from the Monday load that is still inside the hospital - theatres, dressing rooms, stockroom - and hold them in quarantine.
- Keep the positive indicator and the printout in the log; do not discard them and do not overwrite the record.
- Begin the investigation: cycle printout (temperature, pressure, time), Bowie–Dick record, load density and packaging, orientation of hollow instruments, door gasket, vacuum pump, and whether the indicator was incubated and read correctly at the right temperature and within expiry.
- Requalify: three consecutive negative biological indicator runs with Bowie–Dick before the sterilizer returns to service.
2. What do you do about the 21 sets already used on patients?
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Reasoning. The actual per-patient infection risk is low, but it is not zero, and the professional standard is to act on the possibility rather than wait for an infection to appear. The traceability system, not the size of the risk, decides whether you can act at all.
Steps:
- Build the list from the CSSD release log crossed with theatre and dressing-room records: which set, which patient, which procedure, date and time.
- Hand the list to the hospital epidemiologist and the treating doctors. The decision on follow-up - observation, examination, and for invasive procedures discussion of prophylaxis - belongs to them, but the nurse supplies complete and accurate data and does not edit it.
- Record the incident in the hospital's internal register of adverse events, with times and the people informed.
- Do not contact patients yourself with unverified information, and do not conceal the incident if the hospital decides to inform them.
- Audit the traceability itself: if any set cannot be traced to a patient, that gap is the real finding and must be reported in its own right, because next time it will prevent any recall at all.
What not to do: do not resterilize used sets and reissue them, and do not tell the theatre 'the risk is negligible, nothing needs doing'. Both convert a technical failure into a concealment.
3. The surgeon asks you to release the current load and to delay informing management. How do you respond, and what do you write down?
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Two separate requests: release the load, and delay reporting. Both must be refused - politely, quickly and in writing.
Releasing the current load would put another 60-plus patients at risk from a sterilizer whose qualification is now in doubt, and it would destroy the traceability of a second incident. The answer is no, with the reason stated in one sentence.
Delaying information to management is not within the nurse's discretion. Under the sanitary rules and the hospital's patient-safety policy, a positive biological indicator is a reportable internal adverse event. Non-reporting can be qualified as concealment and carries disciplinary and administrative liability, regardless of who asked for it.
The 'lab error' argument is a hypothesis, not a decision. It is verified by checking the incubator temperature, the indicator's expiry and storage, the control indicator and the reading time, then repeating the test - after quarantine, never instead of it.
Frame it around patients, not authority: give the surgeon the recall list and a realistic time for requalification so he can replan his operating list, and offer the hospital epidemiologist as the person who confirms the decision.
Write down: the time of the request, who made it, what was asked, what you answered, whom you informed and when. A factual, unemotional note protects the patients and the nurse.