A rise in ambulances taking patients to A&E departments is among reasons why emergency crews endured 1,400 hours of delays when handing over patients in the last three months, according to a hospital boss.
New figures from the East of England Ambulance Service Trust (EEAST) show patients taken to Norfolk's three acute hospitals waited outside A&E a total of 1,414 hours in April, May, and June.
A spokesman for EEAST said: 'This has a direct knock-on effect to our response times.
'We're working with commissioners and hospitals to reduce handover delays, but it's still a big challenge.'
Patients should be transferred from ambulances within 15 minutes of arriving at A&E, under NHS targets.
Richard Parker, the acting chief executive at Norfolk and Norwich University Hospitals NHS Foundation Trust, said an additional 32 ambulances have been arriving at the N&N each day since June 20 this financial year compared to 2014/15.
Waiting times at the N&N have risen from 248 hours in April, to 245 in May and to 278 in June, leading to an overall total of 771 hours spent by patients in ambulances outside A&E.
That is the fourth-highest total of the 18 acute hospitals in the East of England.
Mr Parker said: 'We are seeing an increase in the demand for emergency care and greater numbers of ambulances arriving at our hospital.
'We are working closely with partners to better understand what is driving this increase.'
He said patients could help by using other NHS services which can treat minor illnesses or injuries such as the Norwich walk-in centre at Rouen Road, and the minor injuries unit at Cromer Hospital.
By contrast figures at James Paget University Hospitals NHS Foundation Trust were among the best in the region, although waiting times have increased from 70 hours in April to 81 hours in June.
Sue Watkinson, the trust's director of operations, said: 'We are in regular dialogue with EEAST about handover times to ensure they are as short as possible.'
She said the rise was due to ambulances arriving on site at the same time.
Queen Elizabeth Hospital King's Lynn is the only Norfolk hospital which has cut waiting times from April (138 hours) to June (127 hours).
Patricia Dunmore, interim chief operating officer, said patients waiting in ambulances were always cared for by an appropriate clinician.
She said: 'There are a number of initiatives the trust is taking to reduce the delays.
'We are currently planning with other partners about how we prepare for winter pressures.'
Have you waited outside a hospital in an ambulance? Email our health correspondent at nicholas.carding@archant.co.uk
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