THE number of public patients waiting nine months or more for surgery increased by 5,680 in January and February following the cancellation of thousands of operations due to severe overcrowding in emergency departments.
As over-stretched emergency departments teemed with patients on trolleys, hospitals had to free up beds, leaving growing numbers of people who were planned for admission back waiting in the queue.
Patients from emergency departments who were already enduring long hours on trolleys had to fill many of the beds instead.
The surge meant that 11,454 public patients were waiting nine months or more at the end of February - up from 5,380 in December.
The overcrowding is now easing but there were still 360 patients on emergency department trolleys and another 76 on wards. Hospitals now have to try to clear the rising backlog of cancelled operations, including those who need an overnight stay or who can be done on a daycare basis.
Hospitals which have seen a significant rise in "long waiters" include Beaumont Hospital and St James's Hospital in Dublin and University Hospital Galway.
The numbers waiting for operations at Beaumont rose from 2,525 in December 2014, to 3,147 in February 2015, while at St James's Hospital, the numbers rose from 1,765 to 2,625.
At University Hospital Galway, the numbers were up from 2,419 to 3,203.
Overall, there are 64,892 people currently on the surgery waiting list, up from 49,983 at the end of February last year. These include people who have just been referred as well as those who have been waiting for longer periods.
Meanwhile, the patient safety watchdog, the Health Information and Quality Authority (HIQA), has said that if more hospitals moved from a paper-based system of recording a patient's vital signs to an electronic early warning system, it would make more beds available and reduce the average length of stay,
However, this kind of technology would cost up to €50m over five years.
Currently this kind of electronic system is almost non-existent in public hospitals.
Dr Mairin Ryan, director of health technology assessment at HIQA, said: "Implementation will require significant capital investment, but has the potential to improve patient safety and efficiency of care and increase acute hospital bed capacity through a reduction in average length of stay."
Other potential benefits include increased efficiencies gained from reduced vital sign recording time, which would leave doctors with more time to deliver care.