The INMO says risks are being taken as a result of the conditions.
The Irish Nurses' and Midwives' Organisation fears a midlands hospital may be particularly susceptible to a second wave of coronavirus.
Latest figures from the HSE show Mullingar Regional Hospital has no critical or general care beds available.
Portlaoise is also operating near capacity with no general beds, while there are 29 free in Tullamore.
Assistant Director of Industrial Relations at the INMO, Albert Murphy, says unnecessary risks are being taken as a result of the conditions:
A midlands TD says some hospitals have cut 10% of their beds to prevent the spread of Covid-19.
Independent Denis Naughten claims that's the case in Portiuncula Hospital in Ballinasloe.
Health Minister Simon Harris will explain the measures being taken to address the issue, during a Dáil debate on the bed crisis today.
Roscommon-Galway's Denis Naughten says urgent action's needed: