What intensive care figures tell us about Prime Minister’s virus prognosis

Britain has been left reeling from the news that Boris Johnson has been admitted to intensive care after his condition worsened. The Prime Minister was diagnosed with coronavirus on March 27 and immediately began self-isolating.

Matt Hancock, the Health Secretary, was diagnosed on the same day, but while Mr Hancock returned to work after just a week, Mr Johnson’s condition has continued to deteriorate.

On Sunday evening, doctors were concerned enough to admit him to St Thomas’ Hospital for tests after his temperature and cough showed no signs of improvement, and on Monday night he was moved to the intensive care unit, a sign that he may soon need ventilation.

A ventilator is required when a patient is struggling to breathe for themselves, and is essentially life support. Mr Johnson is currently receiving extra oxygen, but if necessary he will be sedated and a machine will breathe for him until he is well enough to breathe for himself.

Intensive care statistics are lagging behind the daily updates, so it is difficult to draw definitive conclusions about the survival or progression rates of those admitted to ICUS.

Figures released by the Intensive Care National Audit and Research Centre (ICNARC) over the weekend showed there had been 2,621 admissions to critical care in Britain since the epidemic began.

Early analysis of ICNARC data from 2,249 of those admissions shows that 346 patients have died and 344 have been discharged with a clean bill of health. The average time for each scenario was 4-5 days.

While that may look like a 50:50 survival rate, there are 1,559 people still in an ICU, so that brings the chance of death or discharge within five days down to about 15 per cent.

Of the 690 ICU patients whose outcome was known, those needing ventilation within the first 24 hours of intensive care had the worst outcomes, with just over 30 per cent surviving, compared with 70 per cent of those who did not need such early help.

Prof Mike Grocott, a consultant in critical care medicine and the vicepresident of the Royal College of Anaesthetists, said: “Being in an intensive care unit isn’t all about being on a ventilator. Intensive care is where life support takes place. This involves a highly experienced multidisciplinary team of doctors, nurses and support staff with a wide variety of skills.

“They make use of highly sophisticated monitoring equipment to keep track of the patient’s blood oxygen levels, as well as blood pressure and heart rate.”

A total of 55,242 people have been diagnosed with the virus in Britain, the vast majority of whom were tested after being admitted to hospital with severe symptoms. Those with mild symptoms are asked to self-isolate and ride out the illness at home so it is reasonable to assume that those tested represent the most serious cases.

But one striking detail of the ICNARC figures is that very few people who test positive in hospital end up in intensive care. Comparing the 2,621 admissions to intensive care by April 3 to the cumulative cases – 38,168 – on the same day, it appears just six per cent of people with serious

‘Intensive care is where life support takes place. This involves a highly experienced team with a wide variety of skills’

symptoms ended up in ICU. That figure is interesting because it suggests the modelling by Imperial College that suggested 30 per cent of people admitted to hospital with Covid-19 would need intensive care, was overly pessimistic. Sweden had suggested it was closer to 5 per cent, more in keeping with real-time data.

Given the number of deaths by April 3 – 3,605 – the figure suggests that many people who have died were never admitted to intensive care.

If just 346 of those who died by Friday had been admitted to ICU, as suggested by the report, then fewer than one in 10 deaths are happening in ICUS – which could indicate that many people are dying on other wards, perhaps from other conditions, while also testing positive for coronavirus.

It is possible that not all trusts have reported their intensive care yet, causing a lag with the officials figures. However, the ICNARC report states that the figures come from its “case mix programme” and include all NHS adult, general intensive care and combined intensive care/high dependency units in England, Wales and Northern Ireland, plus some specialist and non-nhs units.

There could also be a lag in the time between deaths and the reporting, and the ICNARC report warns that “due to the relatively low proportion of patients that have completed their critical care, all outcomes should be interpreted with caution”.

Data from China, which looked at the progression of the disease, showed that for the most serious cases, the median time to discharge was 22 days, while the average time to death was 18.5 days. If the figures hold true for Britain it suggests Mr Johnson may not be discharged until the end of April.

The average duration of fever was about 12 days in survivors, which was similar in non-survivors, but nearly half of people still had a cough on discharge. Shortness of breath got better after around 13 days for those who got well after infection.

For those who died, sepsis kicked in around day nine, while acute kidney or heart injury occurred by day 15.

Patients who survived were infectious for up to 37 days, far longer than previously thought.

Patients who died were more likely to be older – an average of 69 years against 52 years for survivors.

The latest British data shows that the virus seems to disproportionately affect men, with just 36 per cent of beds taken by women. Some experts believe the sex imbalance relates to a higher prevalence of smoking or chronic alcohol use in men, while others think men are more likely to have underlying health conditions, leaving them more vulnerable.

Prof Derek Hill, a medical imaging expert at University College London, said: “One of the features of Covid-19 in all countries seems to be that many more men become seriously ill than women – especially [those aged] over 40. Also, people under about 60 seem to have a higher chance of making a recovery from critical illness with Covid-19 than older people.”

But there is no doubt this turn of events means Mr Johnson is very sick.

St Thomas’ has seen some of the highest numbers of coronavirus patients of any hospital in Britain, and is a specialist centre for advanced respiratory support.

Dr Alison Pittard, the dean of the Faculty of Intensive Care Medicine, said: “The experience will give him a special insight into what intensive care is and its importance for the future. I know he will receive the highest quality of care.”