The Western Health Board has announced that it is to lay off 169 temporary workers to meet a budget reduction demanded by the department of Health.
Those being laid off include nurses, ward attendants, laboratory staff and clerical workers.
The Irish hospitals consultants association and SIPTU have expressed concern at the job cuts.
IMPACT has said that it wants to meet the Western Health Board next week to discuss the proposals for cuts in services and jobs.
The union has warned that protests are likely if the board maintains its present approach.