A 700% rise in the number of sick children left lingering in paediatric emergency departments has been recorded by senior medics.

The Irish Association for Emergency Medicine called on health chiefs to reopen hospital beds closed to help cut public spending amid claims that ill youngsters are waiting more than 12 hours on a trolley before admission.

Professor Ronan O'Sullivan said overcrowding was at historically high and dangerous levels and needs immediate attention. The consultant at Our Lady's Children's Hospital Crumlin revealed 71 young patients spent one night on trolleys throughout his emergency department.

"We have patients who are admitted, should be on a ward bed, and they are taking up every physical space in our department and there is no physical space to see new patients who come through," he said. "It is neither ethically acceptable nor physically possible to place children and their parents on hospital corridors."

A study in Our Lady's found the number of "boarded" children (awaiting admission but remaining on trolleys) has soared by nearly 700% in just three years. It reported children are frequently spending longer than 12 hours on a trolley - and in some cases 24 hours.

Medics also revealed the number of children who receive their complete episode of care in the emergency department and never see a hospital ward is now eight times greater than in 2008. The rate of children leaving without being seen has also increased.

Prof O'Sullivan said overcrowding is out of proportion compared with the rise in demand from children being admitted with respiratory infections and diseases during the winter.

"The real issue for overcrowding is a lack of access to in-patient beds. There have been significant cuts in beds," he said.

More than 120,000 youngsters are treated each year in the emergency departments of Dublin's three paediatric hospitals.

Sinn Fein health spokesperson Caoimhghin O Caolain said overcrowding was intolerable.