Medical staff attempted to locate her twice at about 12.30pm and 1.45pm on Monday as they prepared to transfer her from the waiting area for further checks, but she was uncontactable.

She was found unconscious inside an accessible toilet for the A&E waiting hall at 4.30pm and certified dead at 5.06pm, following resuscitation efforts.

The authority did not say why it had taken so long to find the patient in the toilet, but said hospital staff inspected and cleaned the facilities seven times a day.

“There is an alarm inside the accessible toilet for use in case it is needed,” it said. “When the button is pressed, the nurse station will be alerted and the red lamp on the door of the toilet will also be lit. Staff will offer help immediately. The relevant device has been in good working condition.”

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The so-called reference waiting time – hourly estimates posted online – for A&E treatment at 11 of Hong Kong’s 18 public hospitals stood at more than eight hours on Tuesday morning, including at Pamela Youde Nethersole Eastern Hospital. Three others required a wait of more than seven hours.

The authority emphasised that patients would be properly cared for while waiting in the A&E area, with staff making regular checks and offering food.

It also said patients should be accompanied by family members, who should maintain contact with medical staff while they were waiting.

Tim Pang Hung-cheong, a community organiser from the Society for Community Organisation (SoCO), said it was not the first time a patient had died while waiting at the A&E department.

“The hospital may need to review its guidelines so that A&E staff search for patients if no one responds after the patient is called,” he said.

He said hospitals should also install devices that could monitor patients’ vital signs remotely so that actions could be taken immediately if any changes were detected.

“As the patient had entered an accessible toilet, no one would notice if anything happened as it is a single-stall unit. The janitor could probably knock on the door if the patient had stayed in it too long,” he said.

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Pang said motion sensors could also be installed at the toilet so that staff would be alerted if the user had not moved for a long time.

Alex Lam Chi-yau, chairman of Hong Kong Patients’ Voices, said the woman’s death was avoidable, adding that her chance of survival could have been much higher if someone had located her earlier.

He suggested hospitals adopt radio frequency identification (RFID) tags, which are used to track suitcases at airports, to monitor the location of patients.

“As long as the suitcases are still in the airport, their location can be determined immediately with the tag. Information, such as which flight the suitcase is allocated to and who owns it, can also be recorded,” he said.

“It is even more necessary for patients who visit the A&E alone because, in hospitals where everyone is so busy, if no one accompanies and takes care of them, no one will notice if they go missing.”

But he said vital sign monitors might not be feasible as they could be expensive and difficult to maintain, while RFID tags were disposable.

Broken button in station toilet where elderly Hong Kong man died: MTR Corp

Last year, an elderly man was found dead in a unisex toilet for people with disabilities at an MTR station four and a half hours after being reported missing.

It was believed that the emergency button in the toilet was “broken” and the staff did not check all the toilets.

The railway operator later said it would install motion sensors to alert the station if a user in such toilets had not moved for a long time.