The announcement yesterday followed news of critical incidents at Royal Surrey NHS Foundation Trust and Surrey, Sussex Healthcare NHS Trust and East Kent Hospitals University NHS Foundation Trust.

Andrew Hall, chief operating officer at NUH, said: ‘We are experiencing pressures like never before. Despite our teams working tirelessly, the demand on our hospitals far exceeds our capacity. Declaring a critical incident is not a decision we have taken lightly, but it is necessary to protect patient safety.

‘I am deeply sorry for the poor experience this is causing and ask everyone to treat our staff with kindness as they work through this difficult period to deliver the quality of care that you expect.'

NUH said rising demand, winter infections and staff sickness since Christmas had led to significant and unacceptable delays in the emergency department (ED) and across hospital wards.

Queen's Medical Centre, which is designed to treat 350 patients a day, is regularly seeing more than 500 patients a day. On the busiest day of the year (7 January), 550 patients attended the ED.

NUH said hospital bed demand had exceeded all forecasted modelling with patients having unacceptable and lengthy waits on corridors and staff working under extreme pressure.

The trust is taking a number of measures, including: rearranging elective procedures to create capacity for the sickest patients; opening all available beds and spaces; redeploying staff to help alleviate pressures; stopping non-essential meetings and activity; and working with NHS and local partners to speed up discharges and provide community support.