The Irish Nurses and Midwives Organisation (INMO) is imploring the HSE to ''look after its staff'' as it approaches the end of "the worst year for hospital overcrowding" on record.
Figures show that 11,842 patients were admitted to hospital without a bed in December.
Over 121,318 patients, including 2,777 children, went without a bed in Irish hospitals in 2022, according to INMO research.
The organisation says that the HSE has left it too late to address the crisis, as some predicted winter overcrowding as far back as July.
INMO members believe that some hospitals are now unsafe due to the acute pressure on staff and services.
General Secretary of the INMO, Phil Ní Sheaghdha told Newstalk that members are angry with the HSE for its handling of the issue.
"The overcrowding figures were very high and they're straight into another crisis as it is very difficult to provide safe care because the level of difficulty is so high", she said.
"They're also very angry as they don't believe that sufficient preparatory work was undertaken by the HSE."
"They think the HSE left it too late because this was predictable."
The HSE reached an agreement with GPs to provide more appointments.
Some GPs have hit out at the request, warning that they are already "overworked and under-resourced".
Dr Colm Henry, Chief Clinical Officer with the HSE, told Newstalk that pressure has been put on all healthcare workers, from nurses to emergency services staff.
"I want to acknowledge and pay tribute to our healthcare staff... those who've been on call over the Christmas and those who will be on call over the new year... when other people are not working", he said.
"They're provide healthcare at a time that is extremely challenging."
This month, the National Ambulance Service recorded the most calls they've ever received over a two-week period.
Public information campaign
The surge in the number of people catching flu and coronavirus requires a “robust public information campaign” by the HSE, Monaghan GP Illona Duffy said.
She urged anyone who is feeling unwell or has a sick child to check the HSE Under the Weather service before making a GP appointment.
“It is important that those who really need to be seen - those who are really sick - are seeing us and not ending up in A&E”, she said.
“We want to prioritise those who need absolutely to see their GP and try encourage others with minor illnesses to try and self-care and self-manage those symptoms.”
On St Stephen's Day, the Chief Medical Officer Professor Breda Smyth urged people to start wearing masks again on public transport.