Internal documents from the Murrumbidgee Local Health District, seen by The Daily Advertiser, reveal plans to trial the use of assistants in nursing (AINs) at three acute wards for three months from September.

Wagga Base members of the NSW Nurses and Midwives Association passed a resolution on Monday night to oppose the trial, in part due to fears it could affect patient care.

Wagga NSWNMA branch president Amit Gupta said AINs had a "limited scope of practice" compared to registered or enrolled nurses.

Wagga Base Hospital director of nursing Michele Coughlan said "no decisions" had been made about whether or not the trial would progress beyond its proposal.

Ms Coughlan said the trial, should it go ahead, would see AINs assist patients with certain tasks under the supervision of registered nurses as part of a "formal mix" of nursing staff.

"Please be reassured that this trial is not about staff losing jobs. It's not about taking away. It's about adding into and exploring a new role," she said.

Ms Coughlan said it was too early to comment on any long-term staffing changes that could result from the trial, but defended the plan from allegations it is a "reckless cost saving measure" by hospital management.

"I haven't even got out a calculator. I don't know. That's not what this is about, it's about improving the patient experience," she said.

Ms Coughlan said the hospital was hoping to "attract a good quality of AINs that can see our vision and our way of working".

Mr Gupta said he and the other union members were awaiting a response from hospital management by the close of business this Friday.

"We will act on what reply they give us," he said. "Obviously there are a lot of voices of the members who are against this program and they are concerned about the quality of patient care."