The HSE has said that all resources are being used to deal with emergency department pressures.
In an update, the executive said that its National Crisis Management Team is meeting regularly to oversee the response to the pressures.
It said that while the surge in winter virus infections was predicted and planned for, the trends being seen are following the more pessimistic of predicted models.
It said that there has been a reduction in planned surgeries and procedures.
It comes as the members of the Private Hospitals Association have said they are happy to again assist the State in managing the serious capacity issues currently facing the public system
It said that while individual private hospitals are providing assistance at various locations in Dublin and throughout the country, these arrangements are both ad hoc and uncoordinated.
The PHA said that a strategic partnership between public and private hospitals to address the problem on a multi-annual basis, would be a more efficient way of dealing with capacity challenges, which occur with increasing frequency in recent years.
Numbers on trolleys 108% higher than this day last year
The latest figures from the Health Service Executive show that the number of patients on trolleys in emergency departments waiting for a bed today is more than 108% higher than this day last year.
The 'TrolleyGar' figures are collected at 8am and show there are 427 patients waiting, excluding the children's hospitals which have five patients waiting.
The hospitals worst affected are Letterkenny University Hospital with 42 patients, Cork University Hospital with 38 patients and St Vincent's University Hospital in Dublin with 34 patients waiting.
The HSE TrolleyGar figures focus on emergency departments only and differ from the daily Irish Nurses and Midwives Organisation figures, which are normally higher as they include patients placed on wards waiting for admission to a bed.
The INMO said that this morning there were 570 admitted patients waiting for a hospital bed.
It said the hospitals worst affected are University Hospital Limerick with 84 patients waiting, Cork University Hospital with 73; Letterkenny University Hospital with 61 and St Vincent's University Hospital with 39.
The current level of overcrowding is being driven by a rise in respiratory infections like flu, RSV, Covid-19 and other illnesses.
The INMO warned recently that hospitals around the country were stretched to their limits.
The organisation said it had never recorded this level of overcrowding at this time of year before.
670 patients in hospital with Covid
The number of patients with Covid-19 in hospital has reduced by 53 cases compared to yesterday.
Official figures put the number in hospital today at 670 compared with 723 on Thursday.
Yesterday, the HSE announced that the Covid-19 booster vaccination would be offered to anyone aged 18-49.
Meanwhile, the standard VAT rate of 23% is to apply to antigen test kits from Sunday, the Department of Finance has confirmed.
It said this is due to the temporary EU measure of zero VAT rating for the kits coming to an end.
Vigil
A vigil will be held outside University Hospital Limerick on New Year's Eve to remember those who have died while on a trolley during the year.
Speaking to RTÉ's Drivetime, one of the organisers Marie McMahon said that there have been "various promises about improved facilities and things getting better," but she said that improvements appear to have been "put on the back burner".
Ms McMahon lost her husband in 2018 when he died on a trolley in the hospital.
She described the conditions in the hospital: "People lying on trolleys, people sitting in chairs and sliding off chairs because they are not able to keep themselves sitting up.
"People begging to go to the toilet, people begging for a bedpan... no privacy, no respect, no dignity."
