NHS medical director Professor Sir Bruce Keogh’s letter to SHAs at the weekend comes after The Times revealed there had been 239,233 discharges between 11pm and 6pm across 100 hospital trusts last year.

The letter to SHA medical directors reads: ‘While some patients may of course choose to be discharged during these hours, the examples highlighted of elderly patients being left to make their way home by themselves in the middle of the night are obviously unacceptable, and need to be addressed urgently.

‘Discharge or care transfer is of course an essential part of care management in any setting. It ensures that health and social care systems are proactive in supporting patients and their families and carers to either return home or transfer to another setting. It also ensures that systems are using resources effectively.’

Out of the 170 English hospital trusts asked for data under the Freedom of Information Act, only 100 responded.

Sir Bruce acknowledged the difficulty in making ‘like for like’ comparisons because some of the data provided by hospital trusts included self discharges, patients in assessment units and deaths while other trusts focused solely on discharges. Despite this, he warned: ‘The challenge to the NHS is absolutely clear - that patients should only be discharged when it is clinically appropriate, safe and convenient for them and their families.’

He asked the recipients approach all hospital trusts and ask them to review their practices, adding: ‘It is important that trust boards take ownership of this issue, so I would expect medical directors, working with their nursing director colleagues, to ensure that the findings of their reviews are reported to their boards at the earliest opportunity.

‘I would like your assurance that appropriate arrangements are in place in all NHS trusts to ensure timely discharge and care transfer for all patients, and I expect to discuss the outcome of the actions I have requested when we next meet on 8 May.’