Paramedics in Kent dealt with more than 350 calls in six hours from midnight on New Year's Eve - the equivalent of an average day for the emergency teams.
Kent's ambulance service said the calls were mainly drink-related incidents and road accidents.
On an average day, Kent crews deal with about 400 calls.
Colin Taylor, for the South East Coast Ambulance Service NHS Trust, said: "Crews had their work cut out during the New Year's Eve celebrations."
He added: "With an increase in demand, it's really pull out all the plugs.
"Senior management, in addition to doing their normal day job, have also been out manning ambulances and acting as responders in their own right."