An alleged hammer attack that left a man fighting for life at a Sydney hospital could have been caused by a dispute over a will, according to police sources.

Viki Graham, 46, is accused of striking her uncle Brett Jones, 63, while he slept in a ward at Royal Prince Alfred Hospital in Camperdown at 12.15am on Thursday.

Graham was arrested at the scene and taken to Newtown Police Station where she was charged with intent to cause grievous bodily harm and refused bail.

The man and woman are understood to be uncle and niece, with the alleged attack said to have been triggered by a row over the will following a family death.

Court documents allege she walked over to the man’s bedside and struck the right side of his forehead with a pink-handled hammer.

‘I smashed him with the hammer. He stole my brother’s ashes,’ Graham allegedly called out. 

Mr Jones  was understood to be so close to dying, homicide detectives were on standby to launch a murder investigation.

However he is now understood to have since rallied but is still in a critical condition in the hospital’s intensive care unit.

Police sources told the Daily Telegraph investigators are looking into whether the alleged assault is connected to a recent death in the man’s family.

A police fact sheet tendered to court claimed Graham spoke with a nurse as she approached ward nine, and was told it was outside visiting hours.

Local Court Judge J Sweeney described it as a ‘gratuitously violent attack’.

‘The facts are absolutely extraordinary,’ Judge Sweeney said.

‘It is a maximum penalty of 25 years, that is how seriously this offence is viewed by the legislature.’

Sydney Local Health District (SLHD) Chief Executive Deb Willcox said hospital staff have attempted to contact his loved ones after the ‘terrible event’.

‘He’s had a reasonably long length of stay with us, and, by all accounts, (he is) a really lovely person who staff are very fond of,’ she said.

Ms Willcox said the shock incident was not something she had ever experienced, and was ‘distressing’ for hospital staff.

‘They did an outstanding job. You don’t come to work and expect this sort of thing, but their training is so effective,’ she said.

‘They’re just so capable and such good people that they knew exactly what to do.

‘We see people in all sorts of extreme situations. There’s no doubt that this has been a very serious event, and not something that I have been a part of previously.’

No other patients were injured, but Ms Willcox admitted some people are a ‘bit rattled and distressed by the events’.

Hospital staff anonymously told The Sydney Morning Herald they had questions about how the woman entered the man’s ward.

‘This is extremely unsettling,’ a doctor said. 

‘I have never in my many years of practice here ever heard of such a thing (happening) here.’

Visitors are not allowed to access general wards after 8pm, but Ms Willcox said it was a ‘very big and busy hospital’. 

‘Our hospitals are open buildings. They’re open to the public. Our emergency department doors are open overnight, 24 hours a day, seven days a week,’ she said.

‘There are standard visiting hours, but this is a very big and busy hospital.’

In a statement to the Daily Mail, a spokesperson for SLHD confirmed the hospital is assisting police with their enquiries.

Staff who witnessed this distressing incident have also been given access to the employee assistance program, which allows them the opportunity for confidential debriefings.