Liam Doran says "nothing must get in the way of whatever special measures are necessary" to deal with the crisis
Nurses say there has been a 100% increase in overcrowding in our hospitals since 2008.
The Irish Nurses and Midwives Organisation (INMO) recorded 9,381 patients on trolleys last month, waiting for treatment - a 5% increase compared to March 2015, and an almost 100% jump on the 4,701 patients recorded in March 2008.
The organisation says that the health service continues to face intolerable levels of overcrowding, despite all the plans proposed and introduced so far.
Nurses have argued this is due to a continuing lack of beds and staff right across the system, which continues to compromise patient care.
Liam Doran, INMO General Secretary, said the figures "confirm the overcrowding crisis, facing the health service, continues to grow against the backdrop of the steep increase in demand, a shortage of beds and a severe shortage of nurses.
"Notwithstanding this period of political inertia, nothing must get in the way of whatever special measures are necessary to lessen the current environment facing patients and frontline staff," he added.
He also suggested that the situation is now so serious, it is time to cancel elective surgeries.
The Workplace Relations Commission is to undertake a second review of an emergency department agreement between the INMO, HSE and the Department of Health later this month.
The INMO says they will use the opportunity to call on health employers "to bring forward emergency investment, including beds and staff".
Meanwhile, the organisation's latest trolley watch release shows there are still 525 people waiting for hospital beds today, with 423 of the patients on trolleys.
St Vincent's University Hospital in Dublin has 44 patients on trolleys, while 40 people are waiting for beds at University Hospital Limerick.
39 patients are waiting at Our Lady of Lourdes in Drogheda and there are 36 at Beaumont in Dublin.