Almost £200,000 a day is being spent on temporary workers to plug the gaps in Northern Ireland's under-staffed health system.
Spending on agency staff is expected to top £70m this year, having soared by 60% over the last four years.
In some cases nurses costing as much as £87 an hour were brought in to cover chronic staff shortages.
It comes as an investigation by this newspaper reveals how tens of millions of pounds have been spent paying for staff from agencies.
Since April 2010 temporary staff have cost the health service more than £214m.
The figure for the last nine months alone is £53m — equivalent to a staggering £194,000 a day.
Critics have accused health chiefs of "squandering" money on temporary workers, and claimed recruiting more full-time staff would provide much better value.
Expenditure on agency staff was revealed in response to Freedom of Information requests from the Belfast Telegraph.
Between April 2010 and December 2013, the five trusts spent a combined £214,003,622 on temporary staff. That included £68,492,478 in 2012/13 and a further £53,394,850 between April and December last year.
In some cases spending on agency staff has spiralled alarmingly. The Southern and South Eastern Trusts both saw their bills more than double since 2010.
The Belfast and Northern Trusts also saw their agency bills rise sharply. Medical and nursing staff accounted for most of the expenditure.
However, despite increased spending on staff hospitals remain under huge pressure.
Last week it emerged two patients waited on a trolley in the Royal Victoria Hospital's emergency department for over 29 hours.
And in January a Major Incident was declared at the Royal because of a large backlog of patients at the A&E department.
Patricia McKeown from the Unison union warned the system was out of control.
Writing in today's Belfast Telegraph, she states: "Across the negotiating table we have been continually told that the practice has ceased. On the ground we are continually told by workers that it continues at full pace.
"The amount of money being squandered on agency costs is more than the current financial deficit across the entire service, which today stands at £210m."
Since April 2010 more than £30m has been spent on agency nurses alone.
In one case, the Southern Trust paid £87 an hour for agency nurses, although the trust pointed out this was a holiday rate. In other instances, trusts have paid up to £65 an hour for nurses.
Janice Smyth, director of the Royal College of Nursing in Northern Ireland, said stable nursing teams were needed to ensure consistent and high standards of care.
"As a result of cost-cutting exercises and high sickness absence levels, there has been an ongoing over-reliance on the use of bank and agency nurses," she said.
"The overall expenditure of £53m on the supply of health and social care professionals over the past nine months is unacceptably high and raises questions about value for money."
MLAs questioned how much of the money was going to the agencies rather than front line services.
SDLP MLA Fearghal McKinney, who sits on the Stomont health committee, said: "They are staggering and illustrate exactly why there is a pressing need for long-term planning with regards to staffing.
"What isn't in the figures is the amount of money that is going directly to the agencies, and therefore, we can take from that, money not going into frontline services."
UUP MLA Roy Beggs said there had been too much reliance on agency staff.
"Better value for money will be achieved if permanent staff are appointed and allocated on a 24/7 basis rather than the huge reliance on agency service which exists at present," he said.
Health Minister Edwin Poots said: "The use of temporary staff covering staff absence and temporary vacancies is a vital resource to ensure the delivery of safe and effective care and to ensure the continuity of care."
How much have the 5 trusts spent on freelancers?
April to December 2013: £18,025,000
Since April 2010: £71,934,000
The Belfast Trust, Northern Ireland’s largest health trust, had the highest bill for agency staff.
Since April 2010 it has spent almost £72m on temporary workers, including £18m between last April and December. The bulk of the money went on medical staff, which cost £8m in that nine-month period. Nursing (£3.6m) and admin (£3.5m) staff also ran to several million pounds
Based on the current rate of spending, the trust’s agency bill could hit £24m for 2013/14 — an 80% hike.
A spokesperson said the trust employs more than 20,000 people and just 3% of the £700m spent on wages every year goes on agency staff.
“We are charged with running a wide range of services and when we are unable to recruit staff we have, within our existing budget, employed agency staff to ensure continuity of service,” she said.
“We use agency staff to cover short term vacancies, mainly among front line staff.
“Agency staff are therefore vital to the work we do to ensure continuing safe, effective care for patients and clients.”
April to December 2013: £9,954,000
Since April 2010: £38,225,000
In the first nine months of 2013/14 the Northern Trust spent almost £10m on agency staff.
Over half of that sum (£5.4m) went on medics. Admin and ancillary staff also cost more than £1m.
Expenditure increased from £8.5m to £12.4m between 2010/11 and 2012/13 and, at the current rate, could hit £13.2m for the 2013/14 period.
A spokesperson said the trust has employed more nurses on a permanent basis, resulting in a decrease on the requirement for agency nurses to cover sickness, holidays and maternity leave.
“The increase in number of temporary admin staff can be accounted for by a number of one-off projects such as the merging of the patient administration system,” she added.
April to December 2013: £6,339,682
Since April 2010: £25,018,765
Although the Southern Trust had the smallest agency bill, its spending more than doubled between 2010/11 and 2012/13, rising from £4.5m to £9.2m.
In the first nine months of 2013/14, the cost was £6.3m.
A spokesperson said the increase in agency spend, particularly in 2012/13, was caused by a review of admin and clerical support in the acute directorate.
“In order to facilitate flexibility while the review was going on, and to allow for future changes, the trust did not recruit permanent admin and clerical posts into the acute directorate, but used temporary and agency staff on a short-term basis,” she said.
“It is envisaged that this will result in fewer permanent posts in future.”
SOUTH EASTERN TRUST
April to December 2013: £9,197,168
Since April 2010: £36,431,857
Around half of agency costs for the most recent period related to “hospital services”.
The trust’s expenditure rose sharply from £5.8m in 2010/11 to £13.2m in 2012/13.
At the current rate — around £25,000 a day — it could top £12.2m for the whole of 2013/14.
A trust spokesperson said: “The annual agency total spend has increased in recent years, but this year it is expected to reduce by £1m compared with the same period last year, which is related primarily to locum spend. The trust has a high degree of reliance on locums partly related to sustaining rotas in our smaller hospitals.”
April to December 2013: £9,879,000
Since April 2010: £42,394,000
Around half of the spending in the last nine months has gone on temporary staff. It also spent £1.8m on agency nurses in that period.
Unlike other trusts, its spending has remained relatively unchanged since 2010.
A spokesman said it was committed to reducing agency spending by employing staff on NHS contracts where possible.
“Agency staff are necessary to provide continuity of care in the circumstance of absence of existing staff due to sickness and to cover statutory maternity leave,” he said.
The trust said the priority was high quality patient services.