All elective surgery is to be cancelled at Cork's two main hospitals in a bid to tackle overcrowding, which reached a record high yesterday.
According to figures from the Irish Nurses and Midwives Organisation (INMO), there were 620 people waiting on trolleys in hospitals around the country.
The worst hospital affected was Cork University Hospital (CUH) where 73 patients were waiting for a bed - a new record.
The INMO warned that CUH and Mercy University Hospital were operating "beyond their limits".
However, following a "lengthy meeting" between the South/South West Hospital Group (SSWHG), the HSE and the INMO yesterday, a number of measures were agreed to tackle overcrowding.
These include cancelling elective surgery, stopping non-emergency admissions and looking for extra bed capacity from the public and private sectors.
The SSWHG said there had been a "considerably high volume of people presenting at emergency departments (EDs) and flu admissions" across the region, but in particular at the two Cork hospitals.
It appealed to anyone experiencing flu symptoms to contact their GP before attending the ED.
Siptu warned yesterday that the overcrowding crisis is also causing chaos for ambulance staff across the country.
Paul Bell, the union's health division organiser, said: "While the HSE and Department of Health are responding to some areas of the overcrowding crisis, primarily by attempting to boost the number of beds available in hospitals, there seems to be little consideration or emergency planning to make sure ambulances are kept on the road and readily available for communities."
Meanwhile, efforts to persuade consultants to take up hospital jobs with salaries of up to €252,000 and begin the process of ending queue jumping by private patients in public hospitals are to get under way.
The salary will be offered to consultants who agree to exclusively treat public patients, with no private practice.
Health Minister Simon Harris is to meet the two main organisations representing consultants, the Irish Medical Organisation and the Irish Hospital Consultants Association, in the next fortnight to discuss the new Sláintecare doctors' contract.
From the middle of this year, all newly appointed consultants will be under the Sláintecare contract, which will confine their practice to treating public patients for a salary of up to €222,460, rising to €252,150 by July 2022.
Currently most consultants employed in State-run hospitals have a public salary and can top up their income with fees from insured patients.
Existing consultants can continue with this arrangement but they will be offered the chance to switch to the Sláintecare contract.
There are around 500 vacancies for consultants, which was partly linked to a pay gap, leaving doctors hired since 2012 earning €50,000 less than longer-serving colleagues.