SINGAPORE - Four staff at the National Dental Centre Singapore (NDCS) have been punished following an investigation into the hygiene lapses detected there earlier this month.

They include supervisors and senior management who were found to "have fallen short in their level of vigilance, and speed in escalation of incident management", said SingHealth in a statement yesterday. NDCS is part of the SingHealth group.

Disciplinary action taken against the staff members includes warnings and financial penalties.

The investigation was overseen by the SingHealth Risk Oversight Committee, which is part of the SingHealth Board.

"The Committee has instituted measures to improve NDCS' systems, processes and culture to prevent a recurrence. Specific measures have been taken to improve the competency of staff involved in the sterilisation and handling of instruments," SingHealth said.

"We apologise for the lapses, and have started on corrective actions for improvement."

On June 12, the centre said that 72 packs of instruments which had not been fully sterilised were used for patient treatment on June 5 and 6.

In its statement yesterday, the centre explained that one staff member in the Central Sterile Supplies Department did not complete the final step of steam sterilisation of one batch of dental instruments in the late afternoon of June 5. These instruments were then dispatched to outpatient clinics in the late afternoon.

At about the same time, another staff member discovered the error. Staff attempted to recall the affected instruments, but did not manage to recover all of them.

The next morning before clinic operations began, the manager of the Central Sterile Supplies Department - who had not been informed of the incident the previous day - became aware of the issue when she noticed that the sterilisation records of one batch of instruments was not complete. She then initiated a second recall.

The issue was escalated to senior management at about 4pm on the same day. The director of NDCS then activated a third round of recalls.

All instruments were thoroughly checked before clinic hours began on June 7, and additional controls were implemented to ensure that the sterilisation process was complete.

SingHealth attributed the lapse to human error, adding that procedural weaknesses and a lack of vigilance among some staff contributed to the delay in escalating the incident and having it dealt with in a timely manner.

For example, staff who subsequently became aware of the error failed to adequately assess its potential impact, which delayed the full recall of instruments until 24 hours after the error was first noticed.

In addition, instrument packs typically have coloured indicator strips which change colour when the sterilisation process is complete. However, staff at various points - when the packs were issued, received, and unpacked - did not notice that these strips had not changed colour.

"This reflects gaps in the level of vigilance on infection control and patient safety, and, in this particular context, instrument sterility," said SingHealth.

It added that there was also no independent verification of the sterilisation process within the Central Sterile Supplies Department, and a lack of clarity on escalation and instrument recall processes.

Staff have since been reminded to check the sterility of all instruments before they are used. The centre has also carried out an audit of all the sterilisation records in the six months prior to the incident - confirming that sterilisation was complete in all other cases.

SingHealth has also appointed an Implementation Committee to ensure that NDCS properly implements the corrective measures it has suggested.

These include better standard operating procedures for sterilisation and use of dental instruments and improved documentation and inventory accounting processes for when such instruments are sterilised and moved.

Other measures include strengthening the incident reporting and risk management frameworks, and conducting regular training and assessment to ensure that staff are familiar with the process.

In a separate statement on Friday (June 30), the Health Ministry (MOH) said that it has received the incident report from SingHealth and is studying its observations and recommendations.

"MOH will review the findings of the SingHealth investigation, and together with our own investigation and assessments, consider if regulatory actions are necessary," a ministry spokesman said.

"This incident is a timely reminder for all public healthcare institutions of the need to be vigilant in delivering patient care safely, and to have a strong reporting and incident escalation culture. The learning points from this incident will be shared across the healthcare system, so that we can collectively attain a high standard of patient safety and care."

NDCS said that it has contacted all but four of the 714 patients who visited the affected clinics over the two days, and will attempt "various means" to reach the last four.

Following consultations with the doctors, 109 patients requested for blood tests. Of the 107 patients whose blood test results are ready, 19 were found to have had a previous infection of hepatitis B before their visit to the centre.