Cardiff and Vale University Health Board is investigating an issue with part of the ventilation system in surgical theatres at University Hospital of Wales.
It says during routine preparations staff noticed a small number of black specks in the theatre area. As a precaution surgery was suspended in that theatre and a full investigation launched.
Four other theatres have also been affected leading to some operations having to be rescheduled. Patients affected by the issue have been informed.
The health board says there was no evidence of any risk to patients.
Surgery is continuing in other theatres not affected by the issue.
An 83-year-old man has died after falling from the upper floor of a car park at the University Hospital of Wales in Cardiff.
South Wales Police were called to the incident at around 8:10am this morning where the man was pronounced dead at the scene.
Police say there are no suspicious circumstances surrounding the man's death and that local officers are continuing their enquiries.
A male nurse sexually assaulted two women patients at night after they asked him for help with their pain, Cardiff Crown Court has heard. Polish-born Benedyct Czajkowski, 58, is accused of groping a woman after slipping his hand inside her pyjamas.
Czajkowski is alleged to have pulled down the underwear of another woman after she pressed a buzzer in the night at the University Hospital of Wales in Heath, Cardiff.
Prosecutor David Webster said the NHS nurse sexually assaulted the first woman after reporting chest pains.
Mr Webster said the other woman had only recently joined the general ward at University Hospital Wales after experiencing pain in her stomach.
Mr Webster said the woman felt so scared and uncomfortable she got out of bed on a morphine drip and walked to the nurses station in tears to report him.
Czajkowski, of Grangetown, Cardiff, was arrested by police soon after and claimed all his actions were "medically justified" even if they weren't usual medical practice in the UK. He denies three counts of sexual assault and one count of assault by beating.
Cardiff and Vale University Health Board has tonight asked local people for support and to think twice before coming to the University Hospital of Wales' Emergency Unit.
It follows what they call an unprecedented influx of patients over the past 48 hours.
UHB Medical Director Dr. Graham Shortland said the health board was asking for support from the public to reduce the pressure on clinical teams, so they could focus on caring for the sickest patients.
While the sickest and most vulnerable patients are being seen promptly and there are no significant ambulance delays, we would like to ask local people to help us by not coming to hospital with minor illnesses or minor injuries that can be easily dealt with.
Patients who do come to the Emergency Unit with these minor conditions can expect significant waits for treatment, because we are mobilising our resources and focusing our energies on those patients with the greatest clinical need.
This is not a new message, and we ask people throughout the year to make sensible use of the Emergency Unit, but this is even more important when we have so many seriously ill patients at this time of year who need our care the most.”
The health minister Mark Drakeford has said the ambulance service must meet the challenges it faces. It comes after ITV News revealed last night that long lines of ambulances were waiting outside Wales' biggest hospital - The University hospital of Wales.
Concerns were raised last night after reports that queues of ambulances were waiting outside the University Hospital of Wales in Cardiff for hours to transfer patients.
A member of the public contacted ITV Cymru Wales claiming around 14 vehicles were outside A&E with patients inside.
Today Cardiff & The Vale University Health Board has denied that claim.
The board says at it's busiest point there were several ambulances outside and that was for less than an hour's wait.
A spokesman told ITV Cymru Wales 91 per cent of patients were seen within four hours and nobody waited for more than 12 hours.
The board says it is coping well during the busiest period of the year and it has not had to cancel any elective operations and wishes to reassure the public and thank staff for managing the demands on them.
The report from the Royal College of Surgeons says that South Wales is the only part of the UK where patients are dying on cardiac surgery waiting lists.
The RCS spoke to a number of clinical leads, who expressed the following concerns, quoted from the report:
- We heard that patients are regularly dying on the waiting list from their cardiac pathology
- Some services are almost completely failed and some effectively suspended, such as paediatric tonsillectomy
- Children are now regularly being fitted with hearing aids because there is no ability to treat their otitis media with surgical grommet insertion
- Under normal circumstances the provision for urgent and emergency surgery is inadequate
- It was recorded that a patient recently died in the A&E corridor from a ruptured aortic aneurysm
- A direct question was asked to the UHW clinicians as to whether they believed that the services at UHW were dangerous - the universal consensus was that that this was the case
Cardiff and Vale University Health Board says it has developed "a detailed action plan to make sure that we are addressing all areas" of concern, and the Royal College of Surgeons will visit again in September to see if there has been improvement.
The health board is looking at all options to increase cardiac surgery capacity, and looking at proposals to get patients treated more quickly.
Chief Executive Alun Cairns said the health board is working with surgeons "on a range of actions", and looking at what extra capacity could be provided, and improving how it manages emergency, care.
Wales' biggest hospital has been described as "dangerous", in a highly critical report from the Royal College of Surgeons.
It found that "patients are regularly dying on the waiting list from their cardiac pathology" and there was "universal consensus" among clinicians at the University Hospital of Wales in Cardiff that services there were "dangerous."
It warns "the current situation represents a severe risk to patients and urgent action is required."
"A wide range of concerns were raised" by clinical leads at the hospital during a routine visit by the RCS in April - the most prevalent was "the inability to admit patients for elective surgery." There were more than 2,000 operations either cancelled or not scheduled between January and March 2013.
"The main reason for this is the apparent unconstrained admission of emergency patients and the inability to effectively discharge patients", the report said.
Two men from Cardiff remain in a critical condition in hospital after taking what police believe is a legal high.
The men are being treated at the University Hospital of Wales, along with two others.
Police say the two men bought a substance called GBL off the internet.
Officers found the four men collapsed at an address in Llandough.