Hospital admissions: Surgery postponed over patient numbers' rise
Hospitals across Wales say they are experiencing "unprecedented" levels of admissions.
Hywel Dda Health Board said some operations had been postponed as a result, but it had increased bed numbers to cope with the influx.
Aneurin Bevan, Betsi Cadwaladr, Cardiff and Vale and Abertawe Bro Morgannwg have also seen admissions rise.
The Welsh Ambulance Service said it was concerned about the handover delays at hospitals.
Hywel Dda said high numbers of ambulances were visiting its four main hospitals in Aberystwyth, Llanelli, Carmarthen and Haverfordwest and it urged people to "choose well" to help reduce the pressure on hospitals.
Alice Casey, chief operating officer for Cardiff and Vale University Health Board, said the emergency unit at the University Hospital of Wales in Cardiff was coping with exceptional demand.
"We would like to apologise to anyone who has experienced any delay or discomfort during their care in recent days and assure them staff are doing all they can to meet the exceptional demand on our services," she said.
"The emergency unit at University Hospital of Wales has been under consistent pressure.
"On Monday there were more than 455 attendances, the highest this year. Of those 42% were major cases - patients with serious injury requiring complex and expert care."
She said the health board had also been treating a higher than normal number of paediatric cases which had also had an impact on services.
Betsi Cadwaladr said emergency admissions had caused "significant pressure" during the last week at its main hospitals.
But it said its staff had coped tremendously well to "deliver clinical care in difficult circumstances".
Aneurin Bevan Health Board has been coping with similar pressures on Monday and Tuesday at Nevill Hall Hospital in Abergavenny and the Royal Gwent Hospital in Newport.
Abertawe Bro Morgannwg University Health Board said they had also been "experiencing pressures".
The Welsh Ambulance Service said it was concerned at the handover delays at hospitals.
Sue Jenkins, director of service delivery, added: "The Welsh Ambulance Service... continues to play a key role in ensuring that issues and individual delays are escalated to senior managers at all affected hospitals, and that plans are in place to ensure delays are minimised.
"The trust is concerned that pressure across all hospitals in Wales has a direct impact on the ambulance response that is able to be provided to patients who call 999 for our help.
"We do monitor the impact of these delays and are concerned about the impact they have on both our ability to respond to other patients and the experience of patients who wait to be admitted whilst these delays occur."
The Welsh government acknowledged there has been a significant increase in emergency pressures during the last week.
"This is being managed locally by senior executives at local health boards and the Welsh Ambulance Service. Officials have been monitoring the situation closely," a spokesperson said.
"The public have an important part to play at this challenging time for emergency care services by using the most appropriate healthcare service to their needs and thinking before attending the emergency department or dialling 999."
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