Southampton General Hospital says 12-hour waits for emergency patients
Patients are facing waits of more than 12 hours at an emergency department where hospital bosses have claimed to have never seen it so busy.
Doctors at Southampton General Hospital have urged anyone with non-life or non-limb threatening injuries to go to urgent treatment centres instead.
Deputy chief medical officer Dr Trevor Smith said the situation was "extreme".
It comes after a hospital in Portsmouth and the region's ambulance service both said they were struggling to cope.
Dr Smith told the BBC: "I've never seen it this bad before.
"We're in the second week of July - we would normally expect the hospital to be a bit quieter at this time of year.
"It feels like the third week of January - and more. It's extreme."
Analysis: Alastair Fee, BBC South health correspondent
The phrase "perfect storm" is again on everyone's lips.
As the temperature has risen, so has the demand here - it too is almost unbearable.
There's no proper beds for patients, only trolleys.
Without help, this situation could deteriorate further as the heatwave continues into next week.
Nurse Nyza Balintongog said the situation had been even worse earlier in the week.
"Sometimes we don't have spaces in the corridor," she said.
"All of our corridors are full and so are all of the units and departments."
Patient Patricia Fowler said she was "amazed" when she was taken through the ward and saw how busy it was in the department.
"All these people are working so hard and fast," she said.
On Monday, Queen Alexandra Hospital declared a critical incident due to staff sickness and the strain of the prolonged hot weather.
South Central Ambulance Service also declared a critical incident on the same day due to pressures on its services.
Southampton City Council said at the time it had activated plans in care homes and hospitals to support vulnerable individuals and is visiting and monitoring people at high heat risk.
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