Grace Hospital is keeping its mental health unit locked permanently from now on, following concerns about patient safety that surfaced when a 19-year-old patient escaped from the facility on Canada Day.

Officials with the Winnipeg hospital told CBC News about the change in policy on Monday afternoon, after Charity McLellan spoke out about an incident in which her son, Ozzy, disappeared for several hours on Friday.

At the time, the mental health unit was locked only when staff have concerns about a patient. However, that has now changed, said Kellie O'Rourke, the Grace Hospital's chief operating officer.

"Patient safety is very important to us and is a priority in all our units and in an abundance of caution, we have now made this permanently a locked unit. We have converted it to a locked unit," she said.

"There is a balance with that. Certainly there has been a progression of having a more open environment, but in an abundance of caution and making sure that people are as safe we can be, we, like many other sites, have made the decision to convert this to a locked unit."

O'Rourke said Ozzy had "slipped out" of the mental health unit, which was locked because staff were dealing with another patient at the time.

"When he left our site, he was not using a privilege to go out," she said.

"We do know that he slipped out of the facility, of what was supposed to be a locked unit at the time, while the door was open and another individual was exiting."

'I was pretty appalled,' mom said

McLellan said she went to the hospital's mental health unit, where her son has been undergoing treatment for undiagnosed mental health issues for less than two weeks, to take him on a Canada Day outing on Friday afternoon. But when she got to Ozzy's room, he wasn't there.

She said nurses initially told her they would get a health-care aide to look for Ozzy. McLellan said she called police after people outside the hospital reported seeing him.

About two hours after she called police, she was told by hospital staff that Ozzy had, in fact, left the facility, she said.

"What the nurse who was on staff told me was that she was letting another patient out. She was busy at the desk," McLellan said.

Charity McLellan (left) says she wants to know how her son Ozzy (right) could walk out of the Grace Hospital on Friday. (Supplied by Charity McLellan) "When she pushed the button she didn't look to see who was going out, and [Ozzy] ran with his bags … and he got out the door with the person who was leaving."

The nurse said they were just about to call police, McLellan said, adding "it took hours."

"I was pretty appalled."

Ozzy eventually was in contact with his father and he was safely taken back to the hospital.

McLellan questioned how Ozzy could have simply walked out of the hospital's mental health unit, and why it took staff so long to respond.

The incident with Ozzy happened two months after Catherine Curtis, 60, left the same mental health unit and never returned. Her body was found in Sturgeon Creek nine days after she disappeared.

Policies under review

On Monday, the Winnipeg Regional Health Authority said it is reviewing its policies regarding patients who go missing from mental health units.

Jitender Sareen, medical director of mental health in the WRHA, said there is currently a protocol in place in which staff check in with patients at least once an hour.

"If they're off the unit and don't return in time, there's a protocol. At the Grace Hospital it's called 'Yellow Code,' so you have staff check in to see whether the person is on the grounds," he explained.

"If they're not found on the grounds, then the psychiatrist is called and what's called a 'Form 14' in Manitoba is filled out by the psychiatrist and, if needed, the police are called to go and find the person and bring them back to the unit. Usually the bed is held until the person is found."

Sareen said it's up to the medical team to decide whether to notify police and/or the patient's family "within reasonable time."

"People will, for example, be off-ward sometimes for a weekend pass or an overnight pass, and so it requires nursing judgment as well as psychiatry judgment as far as how fast to respond based on the severity of the situation and the acuity of it," he said.