Hospital bosses in Lynn were forced to draft in extra staff this week to cope with patient demand.
An internal critical incident was declared at the Queen Elizabeth Hospital on Monday in response to the high volume of patients attending its accident and emergency department.
Acting chief executive Charles Bruce said the move meant they could continue to provide safe and effective care.
He said: “We remained open to all ambulances and patients attending A&E throughout the incident and the situation was stood down several hours later after the actions put in place took effect and the pressure eased.
“Actions included opened up all our internal escalation capacity and putting out a call for extra staff.
The incident came after health secretary Jeremy Hunt told MPs there needed to be “an honest discussion” with the public about the use of A&E units.
He also suggested the target for treating A&E patients within four hours may need to be revised.
But West Norfolk health campaigner Dan O’Connor has echoed the views of opposition politicians and medical bodies, who argue the NHS is in crisis.
He said: “This past week’s events clearly demonstrate that our NHS is already in its worst ever funding and resource crisis.”
Meanwhile, health chiefs have also announced plans to provide 2,500 extra appointments at 20 GP surgeries in West Norfolk.
West Norfolk CCG chairman Dr Ian Mack said: “This is currently a time of immense pressure in the NHS in West Norfolk for all our services.
“General Practice is already playing its part by supporting patients in their own homes wherever possible.
“The provision of even more additional appointments in surgeries will help to meet the needs of our local community.”