Labor are demanding a parliamentary inquiry into NSW mental health services after sickening footage showed how a mother-of-two was left to die in a hospital corridor.

A naked Miriam Merten was filmed staggering down the corridors of a Lismore hospital in 2014 after being left alone with no food or water in a tiny secluded room for hours.

Ms Merten fell and hit her head at least 25 times, while two nurses have been accused of ignoring her cries for help.

She died of a brain injury the next day.

New Health Minister Tanya Davies said her “stomach turned” when she was made aware of the footage.

View photos A naked Miriam Merten was filmed staggering down the corridors of a Lismore hospital in 2014. More

View photos Ms Merten died the next day. More

“My stomach actually turned at one point,” Ms Davies told News Corp after seeing the images.

“I got to a point where I just closed my eyes because I didn’t want to see what was going to come next.

“I am still pretty much shaken by thinking that was happening to a lady. I was pretty disgusted.”

Labor spokeswoman Tania Mihailuk demanded a “full and transparent review” into her death, saying this is "there Don Dale moment".

“It is sickening and appalling ... Premier Gladys Berejiklian must act immediately.”