Sharps injury at 4:40 pm, and an autoclave with a gap in the log
It is 4:40 pm and you are finishing subgingival debridement on a 47-year-old man. While you remove the ultrasonic tip from the handpiece, it slips and pierces the glove and thumb of your left hand, drawing blood. His medical history form records no blood-borne viruses and no transfusions. Ten minutes later, while you are still at the basin, he mentions to your assistant that he had the hepatitis C cure a few years ago after a period of injecting drug use, and that he has not had a test since. Your hepatitis B vaccination course is complete but you have never had a post-vaccination titre checked. As you clean up you notice the autoclave log has no entries for the previous week, and the assistant says the last weekly validation test failed and was reset. The practice owner has already left for the day.
1. Set out your immediate first aid and post-exposure management, explaining how you assess the risk and why each step is taken.
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First aid, in the first minutes. Wash the wound with soap and running water. Do not scrub, do not suck the wound, do not use bleach or alcohol. Allow a little bleeding, dry the area and cover with a waterproof dressing. Report to the person in charge immediately and complete an incident report - for ACC purposes this is a work injury, and the treatment costs arising from it are covered.
Risk assessment. This is a percutaneous exposure to blood from a patient whose status is uncertain. Approximate transmission risks per injury are up to 30% for hepatitis B from an HBeAg-positive source, around 1–3% for hepatitis C, and around 0.3% for HIV. A solid scaler tip carries a smaller inoculum than a hollow needle, but the risk is not zero, and 'the cure' means a sustained virological response, not that he was never infected or can never transmit.
Actions the same day. Attend occupational health or the emergency department. Baseline serology for HIV, hepatitis C and hepatitis B, plus hepatitis B surface antibody to check your vaccine response, since you have never been tested. HIV post-exposure prophylaxis must be started within 72 hours and ideally within 2 hours, so do not wait for the source result. There is no post-exposure prophylaxis for hepatitis C; the strategy is early detection, with hepatitis C RNA testing at around 4–6 weeks and again at 12 weeks, following local protocol, because treatment is now highly effective. If you are a hepatitis B non-responder, immunoglobulin plus a booster is indicated, ideally within 24–48 hours.
Record and follow up. Document the injury, the device, the patient's known status at the time, who was informed, and the appointments and results. Chase your own results - do not assume someone else will.
2. What is the source patient's role in this, and what do you say to him?
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Tell him what happened. He is entitled to know that the tip that had been in his mouth injured you, that you have a small injury, and that you are following standard post-exposure procedures. This is his information as much as yours (right 6), and a whispered explanation in the corridor damages trust.
Ask for consent to testing. Explain that knowing his hepatitis B, hepatitis C and HIV status would make your management more precise, and ask whether he would agree to be tested or to share the results of his post-treatment test. Consent must be informed and voluntary, and he may refuse. If he refuses, accept it without pressure and manage with your own baseline and follow-up testing.
Keep it confidential. Collect and use the information only to the extent necessary. The result belongs with occupational health, not in the clinical notes where it is not needed and not in reception conversation. Note only that consent was given and where the result went. Do not identify him to other staff, and do not let the fact that he disclosed past injecting drug use colour how he is treated.
If he is positive. It does not change the urgency of your own care, but it sharpens the testing schedule and, for hepatitis C, makes early treatment likely to be curative. Encourage him to re-engage with his own specialist and offer to write a referral - that is good clinical care as well as good manners. Do not frame the conversation as an investigation of him; frame it as two people managing a shared exposure.
3. What do you do about the autoclave, and how do you reason about the risk to patients?
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Immediate. Stop using the autoclave now. Tag it out of service and tell the person in charge today, not next Thursday. Anything processed since the last validated, logged and passed cycle must be treated as non-sterile: quarantine those instruments and trace which patients were treated with them.
What the standards require. AS/NZS 4815 and the Dental Council's infection prevention and control requirements call for every cycle to be monitored and logged, regular validation testing, documented corrective action when a test fails, and recall of affected loads. A 'fail' light that was reset without investigation is a system failure, not an inconvenience: a failed cycle means the load cannot be assumed sterile, and a week of instruments may be affected.
Reasoning about patient risk. Work through it systematically: which instruments, which patients, which procedures, and what the realistic transmission risk is. A scaling with an ultrasonic tip generates more aerosol and blood contact than a polish. Sterilisation failure is a low-probability but real risk of transmitting blood-borne viruses and bacterial pathogens. The practice owner, with advice from the infection control lead and indemnifier, decides whether patients need to be contacted; your job is to make sure the facts are recorded and escalated, not to let them disappear at 5 pm.
If nothing happens. You have a professional obligation not to leave a known risk unmanaged. Escalate in writing to the PCBU, and if it is still not addressed, seek advice from the Dental Council and your professional indemnity adviser. Log it in the health and safety incident register, and the PCBU should consider whether it is notifiable to WorkSafe as an incident that exposed people to serious risk.