The man sought damages after a right-sided central venous catheter was allegedly incorrectly inserted in the right carotid artery and noradrenaline was infused to his brain on Christmas Day, 2015, causing a major stroke and brain damage.

Noradrenaline is used to restore blood pressure after serious conditions including heart attack and drug overdoses.

The incident occurred at Manning Rural Referral Hospital.

The man, who worked in retail and hospitality after leaving school, was left with limited left arm function, impaired cognitive abilities and visual impairment to both eyes and suffered severe depression, NSW Supreme Court Associate Justice Joanne Harrison said in a decision on Tuesday.

"As a result of his injuries and continuing disabilities (the man) has difficulty with independent functioning and requires assistance," Justice Harrison said.

Before the incident he was "a healthy young man who was independent in all aspects of daily life and personal care", she said.

"He lived in Melbourne, away from his family, in an apartment he leased with housemates. As a result of the injuries and disabilities (he) has had to relocate back to Forster to live with his mother."

The health district agreed to a settlement after evidence he will require "ongoing assistance into the future for personal and domestic care".

"He plans to eventually move out of his family home and will need commercial assistance to ensure quality of life. He is likely to commence a National Disability Scheme care plan which will continue indefinitely into the future."

Part of the settlement includes the repayment of $85,000 in Centrelink disability benefits he has received since the incident.

Justice Harrison approved the confidential settlement after being satisfied it was beneficial to the man.