More than 5,000 critical care hospital beds were occupied every day from mid-January onwards, and at one point almost 2,000 more critical care beds were in use than at any point in the previous five winters, NHS England figures show.
While there are some signs that a fall in cases is translating into fewer coronavirus patients being admitted to hospital, critical care bed shortages have emerged as a pinch point for the health service.
On Wednesday the Guardian revealed that dozens of Covid patients a day were being moved between hospitals because of a severe shortage of critical care beds.
NHS England required 5,364 critical care beds on 26 January, its worst day last week, 1,935 more than it did on its previous worst day in the last five winters.
In the week to 31 January, 18 of the 140 relevant acute trusts were running at 99% capacity or more, with 15 at full capacity. By far the largest of these was University Hospitals Birmingham NHS trust, the second-largest trust in England in terms of staff numbers. It had 181 beds available for critical care on average last week, every one of which was full every day.
A further three Midlands trusts were also at full capacity: Chesterfield Royal hospital NHS trust, George Eliot hospital trust and Sandwell and West Birmingham hospitals trust.
Four of the trusts at capacity were in the south-east: Brighton and Sussex university hospitals, Dartford and Gravesham, Maidstone and Tunbridge Wells and Portsmouth hospitals university trusts.
Three hospital trusts in the south-west were also at full capacity all week, as were two in the east of England and one each in the north-west and London.
Part of the pressure is due to the number of beds needed for Covid patients on mechanical ventilation. Since 10 January hospitals in England have been treating more ventilated patients than at the peak of the first wave on 12 April, when there were 2,881 such patients.
This level has been surpassed every day since 10 January, despite the NHS having access to better medication and therefore being less likely to put patients on ventilators. There were 3,324 patients on mechanical ventilation as of 2 February, down from the peak of 3,736 on 24 January but still 443 higher than the first wave peak.
Overall pressure on the health service is easing with encouraging signs on the number of admissions and hospital cases. The number of people being treated for Covid in English hospitals stood at just over 29,000 on Tuesday, down 12% compared with the previous weekly average of 33,047.
Admissions are also down: across England the seven-day average stood at 2,523 in the last week of January, down from 3,288 in the previous week, a 23% drop.
Admissions figures in Scotland for the week to 29 January and Northern Ireland for the week to 1 February show a 27% decrease, while Wales had 12% fewer admissions in the seven days to 2 February than in the previous week.