Ambulance crews were left waiting for up to two hours at a hospital A&E unit because beds could not be found.
The delays at the Royal Sussex County Hospital in Brighton came as a surge in patients combined with a shortage of beds led to the hospital becoming full and managers declaring a major incident.
Ambulance unions fear there will be a repeat of last week’s crisis if the pressure on services continues.
Crews had to stay with patients in the hospital’s A&E department until a trolley or bed became free and they could be handed over to the care of hospital staff.
Jean Calder, who recently visited the Royal Sussex with her mother, said: “I saw 14 ambulance staff waiting in the lobby of A&E because their patients could not yet be admitted.
“I heard paramedics say that delays of this kind had become commonplace, complaining that while held up there, they were unable to attend emergencies.”
South East Coast Ambulance Service Unison rep Peter Steventon said: “Delays in handing patients over obviously has a knock-on effect as it means it takes longer for crews to get back out on the road again.
“It is also not the best thing in terms of patient care.
“It is an issue that is a concern to our members and something that we will be keeping an eye on.”
GMB union organiser Gary Palmer said: “The problem has been particularly bad on occasions at Royal Sussex, but it is indicative of the increasing pressure being placed upon both the ambulance service and hospitals.
“Our members are concerned that stacking ambulances means that parts of Sussex could be left short of cover while they sit there.
“Ultimately there should be no doubt that the delays have an adverse impact on patients experience of the service and may increase risk to patient safety.”
Brighton and Sussex University Hospitals NHS Trust, which runs the Royal Sussex and Princess Royal Hospital in Haywards Heath, remained busy yesterday.
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