United Lincolnshire Hospitals Trust received 21,084 ambulance arrivals at the departments between November and March, according to a report presented to the Health Scrutiny Panel for Lincolnshire.
The figure is equivalent to one ambulance arriving every 10 minutes, 24 hours a day.
Pressures have been made worse due to handover delays, increased length of stay, high admissions and high bed occupancy.
Meanwhile, the level of bed occupancy at Lincolnshire hospitals peaked at 104.67 per cent on December 31, according to the report.
This compares with 95 per cent level of occupancy which half of hospitals trusts nationally were reporting.
Health bosses had previously warned patients in January to be prepared for delays at accident and emergency departments.
Ruth Cumbers, urgent care programme director at Lincolnshire East Clinical Commissioning Group, said that the local health service will be more prepared this winter.
“It’s been really difficult and the report demonstrates that,” she said.
“We’ve seen the national demand reflected in the media and there has been an increase in terms of respiratory illness, flu, vomiting and diarrhoea.
“So there is a lot that we have had to contend with.”
She added that the pressures on Lincolnshire reflect the national demand such as an increase in sicker patients and shortage of staff.
Mrs Cumbers said this year’s winter plan is expected to be complete by July and will be centred around community care.
“We are planning early now and we will have a lot more planning in terms of how we respond to winter,” she said.
“The plan is very much focused around the community and how we can keep people safe in their own communities and within their own homes.”
Simon Evans, director of operations at United Lincolnshire Hospitals Trust, said that overcoming the pressures of winter will be “challenging”.
The winter plan for 2018 will go before the Lincolnshire Health and Wellbeing Board on June 5.