Blow-by-blow account of how non-sterile dental equipment was used on TTSH patients

8 packs of unsterilised instruments were used.

Joshua Lee | January 15, 2019, 12:29 PM

Imagine having some dental work done at Tan Tock Seng Hospital (TTSH), only to find out days later that the hospital used non-sterile equipment on you.

For some patients, this was a reality.

575 patients who visited the TTSH Dental Clinic between between November 28 and December 5 could have been treated with the non-sterile instruments.

What actually happened

The account of the incident was recounted by Amy Khor, Senior Minister of State for Health in Parliament on January 14. 

Sterilisation is a three-step process :

1) Manual cleaning;

2) Disinfection in an ultrasonic washer;

3) Steam sterilisation in an autoclave machine.

On November 28, a TTSH Dental Clinic staff loaded instruments into the autoclave machine for steam sterilisation, the third step in the cleaning process.

The instruments had been through the first two steps prior.

Unfortunately, the staff did not start the autoclave machine.

A chemical indicator outside the pack of instruments would reflect a colour change once the sterilisation is complete and effective.

Subsequently, another staff took out the instruments and stored them without checking that they were not sterilised.

In total, eight packs were stored without completing the sterilisation process and might have been used on patients at the Dental Centre.

The Dental Clinic staff in charge of using the instrument packs did not verify if the instruments were sterilised.

Actions taken

According to a media statement by National Healthcare Group, of which TTSH is a member of, counselling and disciplinary action will be taken against 18 staff who did not adhere to "expected requirements of quality and safe care".

The disciplinary actions include warnings and financial penalties.

Separately, NHG reinforced safety controls across the hospital to prevent the incident from happening again. These included:

  • Strengthening the Dental Clinic’s on-site sterilisation process and ensuring strict adherence by dedicated staff. The steps of loading the autoclave machine and starting of the sterilisation cycle must be linked. The unloading of packs after the sterilisation cycle must only occur after verification of sterilisation;
  • Ensuring strict adherence to the pre-procedure protocol to check for the sterility of instruments before use;
  • Optimising the workflow to improve the reliability of the sterilisation process to reduce the probability of human error;
  • Strengthening incident reporting frameworks and ensuring escalation protocols are well understood and adhered to by staff; and
  • Refining training, competency assessments and regular audits to reinforce staff compliance and understanding of the importance of safety checks that are built into the system, and with full adherence to all processes.

In her answer in Parliament, Khor said that the Ministry of Health has also instructed all public and private healthcare institutions to further strengthen their systems.

This includes heightened vigilance throughout sterilisation processes and conducting internal quality audits. All institutions were also instructed to review their sterilisation processes.

Noting that the risk on infection in this particular incident was particularly low, Khor nonetheless said that it was a "serious breach of the institution's infection control system".

She added that the Ministry will also review NHG's report regarding the incident and consult the relevant domain and technical experts to see if healthcare sector-wide actions need to be taken to prevent a re-occurrence.

Top image credit: Stock photo by Jon Tyson on Unsplash