WATCH: Helpless 89-year-old dementia patient punched 11 times by cold-hearted care worker

An 89-year-old dementia patient's family caught a care worker punching the man 11 times in a shocking hidden camera video.

The Ottawa Citizen reported that Georges Karam is immobile, largely nonverbal and frequently confused and disoriented, but his family noticed that he had unexplained injuries. Suspecting something was wrong, they installed a high definition camera in his room at the city-run Garry J. Armstrong long-term care home in Ottawa.

"The video, which was provided to the Citizen by Karam’s family, shows the elderly man lying in bed as personal support worker Jie Xiao yanks him back and forth while removing his diaper," wrote the Citizen's Elizabeth Payne. "Karam suffers from Alzheimer’s and Parkinson’s disease and needs a wheelchair to move around."

On March 8, the camera caught Xiao, 44, pummeling Karam's face with his gloved fists 11 times in 28 seconds.

On Tuesday, Xiao pleaded guilty to assault and is expected to be sentenced later this year.

Karam's grandson, attorney Daniel Nassrallah set up the camera and made sure that the care center's staff knew that it was in place and recording, the Citizen said.

“We have a camera on him, and even that doesn’t deter him. To me, that’s mind blowing," Nassrallah said.

When he saw the video of his grandfather being assaulted, Nassrallah said, "I literally stood up and fell down, my legs gave way because I didn’t know how to respond to this."

The family reported Xiao to the police. Karam was taken to a hospital and checked for injuries via CT scan and found to have only soft tissue injuries and minor abrasions. He has since been returned to the home.

Nassrallah said part of what is particularly galling in this situation is that Xiao has been trained as a specialist in dealing with dementia patients.

“A person in a state of dementia reverts to childhood. It’s fight or flight. My grandfather can’t fly, he can’t run away, he can’t get away from the situation, he’s immobile. His hands are being held, he’s being demeaned, he’s being thrown around in some instances, he’s not being taken care of properly,” Nassrallah said. “This is torture, this is punishment, this is cruel treatment.”

Ottawa Police spokeswoman Det. Hilary Rao called the video "definitely disturbing."

Janice Burelle -- Ottawa's general manager of community and social services -- said, "I deeply regret that one of our residents was subjected to this incident. The actions of this worker are completely at odds with our mission and our commitment to the health and the well-being of our residents. Long-term care will not tolerate any form of abuse of residents. There can be no excuse for even a momentary lapse in the high standards that we, residents and their families expect of the people to whom we have entrusted the care of those who call our facilities home.”

The incident comes at a time of growing concern about Ottawa's long-term care facilities. Former nurse Elizabeth Wettlaufer confessed in June to murdering eight patients in long-term care by injecting them with lethal doses of insulin.

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