Hospitals usually see a drop in patients going to the emergency departments in summer - around 10 per cent.

That didn't happen in 2019, according to Shelagh Smith, the chief operating officer of Barking, Havering and Redbridge University Hospitals Trust (BHRUT).

Doctors usually start seeing more patients and sicker patients from around January 2, but Ms Smith said they started to see that from November.

There's no single way to deal with the booming demand. The trust's approach includes moving scheduled treatments to prioritise emergency care and working with other care providers like GPs and councils to make sure people are getting the right treatment - only going to hospital when they need to, when it's the most serious.

"If the patient gets to hospital they should really need to be here," said Ms Smith.

"Then it's how do we treat them quickly and get them home.

"We build [everything] into a big plan looking at who's doing what - and then we say a big prayer.

"When we're preparing for winter, we're doing everything to make hospital the last resort."

Making sure that people only go to hospital is important not only to relieve pressure on the already strained service, but because once someone's admitted it can be hard to get them fit enough to leave again.

"We know admitting a frail patient to hospital is not always the best treatment," said Jack Stevens, BHRUT's lead nurse for emergency care in acute medicine and ambulatory care.

"Sometimes, particularly with patients that've got cognitive impairments, taking them out of the home can create more complexity."

To stop that, the trust is working to keep people out of hospital until it's necessary.

That's especially the case for children and the elderly - two areas that are under particularly high pressure.

For the elderly, the frailty unit at the Queen's emergency department diverts patients to services that can serve them better without hospitalising them.

"I wouldn't say we operate at crisis [levels] all the time," Ms Smith said. "We operate pretty close to crisis. We have alerts going from green when everything's fine, amber, red alert.

When this newspaper spoke to Ms Smith on a weekday in mid-December, Queen's Hospital was on "internal incident": "We've got every clinical person working, focusing on the emergency pathway."

Those incidents typically last for 24 hours.

"This time of year we are constantly on red alert. Patients are kept very safe.

"We're managing that crisis. We always manage it very well. Patients are kept very safe and we have processes to make sure at these times outpatients come to no harm."

Raising the profile of different places to get help is part of the effort to tackle demand and nurse Stevens wants to make people aware of the surges seen at different times.

He said it's common to see a lot of children coming in at around five - after school and when parents get home from work.

Patients also need to understand that to go to the emergency department, their condition has to be life-threatening and urgent treatment centres are for things that are serious and can't wait, like broken bones and minor head injuries.

In the 12 months from April 2018 it was common to see 1,000 patients a day across the emergency departments in Queen's Hospital and King George's Hospital, according to a BHRUT annual report.

In that report, staffing was identified as a "significant issue", with the trust routinely turning to agency staff to fill gaps.

One of the ways the trust is trying to fix the problem is with advanced clinical practitioners - experienced health care professionals who have done additional training to do more jobs in the hospital. They come from the ranks of the likes of nurses and paramedics.

There are 13 ACPs in the Queen's emergency department.

Even with those clinicians, the trust is relying on people using the right service to help stem the stress at the NHS this winter.