What happens to coronavirus patients when they are admitted to intensive care?

British medics were clear last night – Boris Johnson would not be in an intensive care unit unless he definitely needed to be.

The move marks a serious escalation in his treatment and will not have been taken lightly by his team of doctors at London’s St Thomas’ hospital.

‘The NHS, particularly in this moment, doesn’t give up intensive care beds just for people to be looked over,’ Reading University’s Dr Simon Clarke said.

So what is in store for a patient battling coronavirus who requires ICU treatment?

Medical teams treating the most seriously ill patients will work one-on-one in the wards and have a host of equipment to measure every aspect of people’s bodies from heartbeat and temperature to their exact blood oxygen level – a key indicator in coronavirus deterioration.

Even within ICU, some patients will be ‘better’ than others. Sources told The Times last night that Mr Johnson had needed four litres of oxygen, compared to 15l for some more desperately ill patients.

At one end of the spectrum, those being treated will remain conscious and ‘continuous positive airway pressure’ or CPAP treatment is used.

With this, patients are put in a hood or tightly fitting mask and oxygen is delivered at higher pressure to keep the airways open. This is especially useful for people suffering pneumonia, which sources denied was the case for Mr Johnson.

But at the other end of that spectrum, mechanical ventilation will be necessary – with the patient placed in a medically induced coma. Tubes will be placed into their windpipes to breath for them and their heart, lungs and other organs will be constantly monitored. Drugs and fluids, as needed, will be dispensed.

Derek Hill, Professor of Medical Imaging at UCL, said tonight: ‘A ventilator can be invasive, involving a tube being put down the patient’s throat, or non-invasive, for example, breathing through a specialised mask. Invasive ventilation tends to be recommended for COVID-19 patients.’

The ventilators – which use sophisticated software and sensors to adjust the levels of oxygen required – can be administered to a conscious or unconscious patient.

The Prime Minister may be put on an ECMO machine, a highly specialised device that is more sophisticated than a ventilator.

St Thomas’ is one of just six UK hospitals with a centre for adult ECMO – extra-corporeal membrane oxygenation. The machines, which take the blood out of the body to remove the carbon dioxide and replenish the oxygen, are used on patients whose lungs are not working properly.

The treatment costs an average of £45,000 a head, but makes recovery much easier because it allows the lungs time to heal.  

Wherever course of action his doctors are using on the Prime Minister, medics said being on an intensive care ward – even being in a private room – would be frightening for a patient and could last days even if he is not hooked up to machines.

Intensive care units can be overwhelming places for both patients and their loved ones, although the highly transmissible nature of coronavirus means many hospitals have stopped or restricted visits.

Linda Bauld, a public health professor at the University of Edinburgh, said: ‘The admission of the Prime Minister to intensive care is of huge concern and illustrates just how indiscriminate this virus is.

‘Anyone anywhere, including the most privileged in our society, can be affected and can become seriously ill. It is imperative now, more than ever that the rest of us comply with government guidelines to stay at home and not put others at risk.

‘All our thoughts will be with the Prime Minister and his family, and the many other families who are facing similar circumstances with critically ill relatives.’

St Thomas’ is a major teaching hospital that specialises in critical care.

It is situated on the Thames opposite the Houses of Parliament and has two intensive care units that house 19 permanent beds. St Thomas’ also specialises in heart and lung surgery, obstetrics and gynaecology and children’s medicine.

Once a patient no longer requires intensive care they can begin what is often a long road towards a full recovery, although sometimes there are lingering problems.

Health experts say that as a general rule patients will need a week of convalescence for every week that they are in intensive care.

And they agreed tonight that the PM’s admission to intensive care means he is ‘extremely sick’.