Come 8 a.m. on Tuesday, hospitals, care centres and medical units throughout the State will take a massive step into the unknown. No one knows exactly how the health sector will operate with its 28,000 nurses on strike, but operate it must.
Emergency cover has been agreed for essential services like intensive, coronary and critical care units, and basic care will continue to be provided to the terminally-ill and severely disabled. However, a comprehensive contingency plan is far from complete, with negotiations set to continue until the last minute between the nurses' unions and health service employers.
Adding to the uncertainty is the fact that emergency procedures are being drawn up locally by each nurses' strike committee, giving rise to disparities across the State.
Already the public is feeling the impact of the dispute, with the cancellation of thousands of non-urgent operations. From yesterday, most hospitals were admitting only minor elective surgery where patients would be discharged before the strike began.
Letters have been sent to patients who require ongoing treatment, telling them not to turn up for appointments next week. An estimated 7,000 out-patient appointments a day will be cancelled.
But this is only a taster for the disruption due to begin on Tuesday. All eyes will undoubtedly be on the accident and emergency wards of acute hospitals where, under emergency rostering procedures, staff numbers will be reduced to about a quarter of normal.
It is here the strike will hit home hardest as the State's 1,200 hospital consultants and 2,500 junior doctors will be forced to take up the slack. Normally nurses would handle the bulk of the workload from admissions to casualty, which average about 1,000 a day.
For the strike, however, "extended duties" like prescribing the injury, ordering an X-ray, carrying out stitching, administering injections and monitoring the patient will fall to medical staff.
"Delegating intravenous injections alone, thousands of which nurses would carry out a day, will have a massive impact," says Finbarr Fitzpatrick, general secretary of the Irish Hospital Consultants' Association. "At the best of times mistakes are made, but when people are under pressure and carrying out multiple duties it is all the more likely."
Nursing staff will provide assistance only in emergency cases, which will be distinguished from others by the consultant in charge. While a full nursing presence will be guaranteed in operating theatres and intensive care units, it will not extend to hospital wards where there will be pressure to discharge people from care as soon as possible. The Health Services Employers' Agency maintains, however, that no patient will be released until it is safe to do so.
Similar arrangements have been made in maternity hospitals. Midwives will staff delivery and intensive care units but will refuse to carry out extra services such as electronic foetal monitoring and postnatal support. Mothers who would normally stay with their infants for between two and three nights in hospital will be asked to leave within 24 hours of birth.
Much of the burden is to fall instead on general practitioners. Health boards and hospital managers have urged people to make them their first port of call. Doctors' waiting rooms are set to become mini-casualty departments as hospitals divert all minor injury cases to GPs for initial examination. They in turn will send only emergency cases to hospital.
"It's going to mean a significant addition to our workload," says Dr Liam Lynch, chairman of the Irish Medical Organisation's GP committee.
As well as taking over hospital duties, GPs will have to meet the needs of patients normally serviced by community nurses. These include childhood surveillance, visiting the elderly, routine wound dressing and monitoring new-born babies.
The other group forced to carry much of the workload will be the families of patients, particularly of those in respite care. A number of special-learning schools and residential care centres for children with disabilities have already written to parents asking them to take their children home for the duration of the strike.
Similar services for the elderly, such as community psychiatry and respite admissions to hospitals and day-care centres, have been cancelled by health boards which have urged relatives to offer alternative assistance. Dr Mary Hynes, the Western Health Board's director of public health, says: "It would also be helpful if relatives, friends and neighbours kept a special eye on those in the community who are vulnerable, for example old people living at home."
Uncertainty continues to surround a number of specific services such as haematology and oncology. Nurses have agreed to maintain a basic presence in cancer units. But there will only be a limited service.
The extent of cover for mentally-handicapped patients and for diabetics remains vague. As with other areas, the quality of care is likely to diminish if the strike continues as available staff are diverted to emergency services.
For up-to-date information on cancellations and cutbacks, patients are asked to contact their local clinic or hospital. However, even this may prove frustrating as nurses normally answer phones and provide information on patients and services.
The ultimate cost of the strike is anyone's guess. Hospital consultants are predicting overcrowding and huge delays in casualty wards, which will add to the suffering of patients and could cause death. But they stress the hidden costs are incalculable. The lost caring hours, the thousands of missed appointments, the collapse of early intervention in the case of vulnerable patients: all have untold consequences.
It will take months, if not years, to recover from the shock, says Mr Fitzpatrick. "If it lasts three weeks that'll be 10,000 more people on the waiting lists and 100,000 cancelled out-patient appointments. It's a frightening thought."