A review of cardiology care in the Hywel Dda University Health Board area has recommended several measures including the creation of a hub at Glangwili Hospital in Carmarthen, with patients transferred there from as far away as Ceredigion and Pembrokeshire.
The health board says it will consider the recommendations as a matter of urgency.
The health board will make an official response to the report in May.
Hywel Dda Health Board has confirmed that paediatric care at Withybush Hospital in Haverfordwest has been downgraded.
The 24-hour unit will now only operate for 12 hours, staffed by nurses and doctors.
"The detail of what this service will look like and how it will be delivered has not been finalised and will be developed by our clinical staff and planning teams over the coming months", a spokesperson said.
Bowel unit services at Bronglais Hospital in Aberystwyth are being 'downgraded by stealth' - a former surgeon there has claimed.
David Jackson says services are being centralised to Withybush Hospital in Haverfordwest.
For one woman that's meant spending thousands of pounds in travel and accommodation to visit her husband.
Linda Davies had assumed Meu would be treated 45 minutes away in Aberystwyth.
Instead they have to travel up to three hours to Haverfordwest. The local health board rejects the 'downgrading' claims. Kevin Ashford reports.
Concerns have been raised over claims that a bowel surgery unit at Bronglais Hospital in Aberystwyth is being downgraded by stealth and moved to Carmarthenshire with a massive impact on patients. Hywel Dda Local Health Board has rejected the claims.
Linda Davies' husband, Meu, was diagnosed with bowel cancer. His treatment has involved numerous hospital visits and overnight stays.
Linda had assumed that would mean travelling the 45 minutes from their mid-Wales home at Llanbrynmair to Aberystwyth for appointments at Bronglais Hospital.
Instead they've had to make half a dozen trips to Haverfordwest in Pembrokeshire for treatment at Withybush Hospital - a journey which can take up to three hours in the car.
There are claims that a bowel surgery unit at Bronglais Hospital in Aberystwyth is being downgraded by stealth and moved to Carmarthen.
It is thought the move could mean patients having to travel up to three hours for treatment.
Hywel Dda Local Health Board has rejected the claims.
Dr Sue Fish, Medical Director at Hywel Dda Local Health Board, said: "We openly announced some time ago that we needed to undertake a review of surgical services across Hywel Dda - including colo-rectal cancer surgery.
"That review is ongoing and we expect it to be completed within the next few months.
"Whilst this review is ongoing, our responsibility is to ensure that patients receive the highest standard of care possible."
A health board has denied claims that it has decided to end consultant and doctor led maternity services at Withybush Hospital in Pembrokeshire and move them to Glangwili in Carmarthen next year.
There have been reports that staff at Withybush were told some services would end next March.
A spokesperson for the Hywel Dda Health Board said discussions were still ongoing about how services would be arranged, and that proposed models would be submitted to the Welsh government in the next few weeks.
Hywel Dda Health Board has denied health union claims that it is cancelling operations this winter to save money.
But it says some surgery - such as knee and hip replacements - will be postponed.
The health board says it has a responsibility to ensure continued safe care at this time of increased pressure and is putting plans in place now to respond to the anticipated increase in activity over the winter.
Dr Phil Kloer, Director of Clinical Services, said, “There have been too many operations cancelled at the last minute due to emergency admissions. In previous winters, we had up to 160 additional beds in place often being managed by temporary staff. This is not a position we can sustain this year.
”We would like to reassure patients that if they have an urgent clinical need they will be seen. Emergency and cancer procedures, the vast majority of orthopaedic day surgery and other elective procedures will also continue.”
The health service union, UNISON, claims all planned orthopaedic surgery for four main hospitals in the Hywel Dda Health Board area have been cancelled until April 2014.
It says the hospitals affected will be Prince Philip, Glangwili, Bronglais and Withybush Hospitals.
Unison says the health board has to make financial savings and as a result hip and knee replacements will be cancelled.
UNISON Branch Chairperson, Wendy Evans, said, “The Health Board already has a waiting time of 15 months for patients awaiting orthopaedic surgery. This will clearly add at least another five to six months to their waiting time, causing further distress."
The union says it has written to the Health Minister, Mr Mark Drakeford to complain about the decision.
Health Minister Mark Drakeford has confirmed the A&E unit at Prince Philip Hospital, Llanelli, will become a nurse-led department.
The local Community Health Council had referred the Hywel Dda Health Board's plans to ministers, following the publication of the plans in January.
A special scrutiny panel was set up to provide advice to the Health Minister.
The panel has not yet made a decision on planned changes to neonatal care in the area.
The Health Minister says he has asked the health board to carry out further analysis of the proposals for obstetric, midwifery and gynaecology.
Dr William Roberts, chair of the aBer health campaign group, told ITV News he "welcomes" today's change of Health Minister.
"I look forward to constructive change from a new minister" he says.
The group was set up to oppose proposed changes to services at Bronglais Hospital, Aberystwyth.