Reason Behind Improperly Sterilised Equipment at Tan Tock Seng's Dental Clinic and Preventive Measures Put in Place

Mr Leon Perera asked the Minister for Health with regard to recent incidents of improperly sterilised equipment at dental clinics (a) what measures are currently in place to ensure the proper sterilisation of dental instruments in public and private clinics; (b) what training is being done to ensure staff compliance with the sterilisation process in licensed healthcare institutions; and (c) how often are audits or checks conducted in such institutions.

Thank you. Patient safety is of utmost importance to our healthcare institutions. We are disappointed with the lapse at the Tan Tock Seng Hospital's (TTSH's) Dental Clinic, which had led to the use of eight packs of dental instruments that had not undergone the final step of sterilisation, and we apologise for the incident.

Within our public healthcare institutions where reprocessing and sterilisation of instruments are conducted, there are standard operating procedures in place to ensure that these processes are completed properly. There are at least three layers of checks. First, the mechanical parameters of the sterilisation machinery, such as temperature, pressure and time, are recorded. Staff operating the machines would check the parameters after each cycle of sterilisation to ensure that the parameters are correct to achieve effective sterilisation.

Second, a chemical indicator affixed outside the pack of instruments to be sterilised would reflect a colour change to verify that sterilisation was complete and effective. Only then should the staff in charge of sterilisation release the instruments for storage and use.

Third, end-users should ensure that the instrument has been sterilised before use by verifying the change in colour of the chemical indicator as well as checking the integrity of the packaging.

Staff who perform sterilisation processes would have to undergo proper training. In our public healthcare institutions, such training is a basic requirement of a new staff’s orientation programme. Competency assessments are also being conducted before staff are deemed competent for the function. In addition, staff are regularly sent for further training and re-assessments in order to maintain their competencies.

The public healthcare institutions also conduct routine internal audits on various critical functions, such as the sterilisation process and workflow. Depending on the institution’s internal work processes, such internal audits may take place as often as once every six months, involving various departments, such as Infection Control and/or Quality Assurance. The audit findings are typically shared at learning platforms, where improvements and recommendations will be made system-wide.

The National Healthcare Group (NHG) has conducted an investigation and the Ministry has received its review report on 8 January 2019. NHG’s investigations showed that the incident was a result of human error, with a lapse in adherence to the established sterilisation process and verification protocol. On 28 November 2018, a staff from TTSH Dental Clinic loaded instruments, which have undergone manual cleaning and disinfection in an ultrasonic washer, into the autoclave machine for the final stage of steam sterilisation. However, the staff did not initiate the steam sterilisation cycle. Subsequently, the packs were unloaded and stored without realising that the packs had not undergone the final step of sterilisation. These packs were not verified for sterility before use. After the instruments were recalled, eight packs were unaccounted for and could have been used on patients. NHG's investigations also revealed supervisory lapses in the sterilisation workflows and escalation of the incident.

Following the incident, TTSH has reinforced safety controls across the hospital to improve vigilance and adherence to processes, so as to prevent any recurrence. Specifically, safety controls for the TTSH Dental Clinic have been fortified in the following key areas.

Firstly, strengthening the Dental Clinic's onsite sterilisation process and ensuring strict adherence by dedicated staff tasked to carry out sterilisation of the instruments. Specifically, 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.

Secondly, ensuring strict adherence to the pre-procedure protocol to check for the sterility of instruments before use.

Thirdly, optimising the workflow to improve the reliability of the sterilisation process to reduce the probability of human error.

Fourth, strengthening incident reporting frameworks and ensuring escalation protocols are well understood and adhered to by staff.

And fifth, 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.

The NHG Review Committee has also recommended new standards for critical steps in the sterilisation process, improved organisation and supervisory management of sterilisation processes, and clarity in incident escalation process. Some examples include (a) designating a single operator to perform the entire sterilisation process, and (b) ensuring identification of operators of critical steps to enable tracking and traceability in the event of sterilisation failures. The Ministry will closely monitor the implementation of remedial actions and standards of care at TTSH through follow-up compliance audits, focusing on the area of reprocessing and the sterilisation of instruments.

Counselling and disciplinary actions were recommended for 18 management and staff involved in the incident. These include warnings as well as financial penalties.

Immediately after the incident, the Ministry has also instructed all public and private healthcare institutions to further strengthen their systems and ensure staff awareness and strict adherence to all processes for patient safety and care. These include reminding healthcare institutions to: (a) heighten vigilance throughout the sterilisation process and check that instruments used are properly sterilised before being used; (b) step up on competency trainings for all staff; and (c) ensure periodic internal quality audits are conducted on the sterilisation process, as well as the delivery of sterilised instruments to the users.

We have also asked all healthcare institutions to conduct immediate safety reviews of all their sterilisation processes and to ensure that staff are compliant with the processes.

The Ministry also conducts random ad hoc audits at selected institutions to check on their state of compliance. This is in addition to the routine inspections of all public and private healthcare institutions which we conduct every two to five years as part of the process of licence renewal. Healthcare institutions with non-compliances have to rectify them and further inspections are made to verify that such non-compliances have been duly addressed.

The Ministry will review the findings of the NHG review report, consult relevant domain and technical experts, and consider further actions to be taken to reduce the risks of a re-occurrence across the healthcare sector. A review of local practices will be undertaken to ensure that they are up-to-date and aligned with the best available evidence for safe sterilisation and disinfection of used instruments. We will then share the learning points across the healthcare system to improve patient safety.

While we note that the risk of infection to affected patients is extremely low in this incident, it is nonetheless a serious breach of the institution’s infection control system. Our healthcare institutions need to be more vigilant to enable the detection and mitigation of incidents expeditiously. In this regard, the Ministry would be working with the healthcare institutions to further enhance the culture of vigilance amongst healthcare professionals so as to promote safe and good quality patient care. The Ministry is also conducting its own investigation and will consider if further regulatory actions are necessary.