Medical staff have been urged to communicate better with the family of patients who are dying, after an audit found tens of thousands of patients are having do not resuscitate orders imposed without their loved ones' consent.

Hospitals are failing to tell relations that they do not intend to attempt potentially lifesaving techniques to save their loved ones, according to the Royal College of Physicians.

Its 2015 audit of 9,302 dying patients found that 20%, or one in five families, were not informed of the plans.

Nearly half of all deaths in England occur in hospitals, a figure of more than 220,000 in 2014, the college said.

Its audit found 94% of the cases it looked at had an order for health workers not to attempt cardiopulmonary resuscitation (DNACPR) in place at the time of death.

While discussion by a senior doctor with the patient about the imposition of an order was recorded in 36% of cases, 16% had no reason recorded for why there was no discussion.

Among the report's recommendations, it said: "Patients' concerns, and those of the people important to them, need to be more fully documented."

It added: "Recognition of the possibility that a patient may die should be communicated to the patient, people important to the patient and staff, and documented in the case notes as early as possible. The recognition of dying should be reviewed by a senior doctor or nurse."

The audit's chairman Professor Sam Ahmedzai told the Daily Telegraph: "When a decision has been taken, it is unforgivable not to have a conversation with the patient - if they are conscious and able - or with the family."

He also said doctors needed to be more open with dying patients, as half of patients identified as likely to be dying were dead within a day.

"This is being done very late in the day - as doctors we just don't like to face up to it," Prof Ahmedzai added.

He said the medical profession needed to do better but in many cases resuscitation would be inappropriate.

"The majority of people who are dying in hospital are not dying of sudden heart attacks or blood clots, they are dying with cancer, with dementia, with other chronic conditions and that is meant to be a peaceful passing away," he said.

"It would be quite inappropriate for a doctor, a crash team, to come along and start pounding on the chest, putting tubes in when actually the person is reaching the end of their life and no amount of resuscitation is going to help."

But he told BBC Radio 4's Today programme that more needed to be done to inform patients' families about the decision: "We have to confess that actually we are not as good at this as we should be."

Explaining some of the 20% of cases where no-one was informed, he said: "Often it's because there was no family member - a person living alone or from a care home - or because we tried to contact the person but were unable to do so in time".

Merry Varney, from law firm Leigh Day which represented the family of 62-year-old Janet Tracey who died at Cambridge's Addenbrooke's Hospital in 2011 after an order was placed on her notes without proper consultation, said the figures suggest "widespread unlawful practice" in how the orders are used.

Ms Varney said: "The figures released today suggest widespread unlawful practice in relation to how do not resuscitate orders are imposed on patients.

"The Court has made it very clear that unless there are exceptional or compelling reasons, patients must be consulted about do not resuscitate decisions and informed about any do not resuscitate order before it is imposed. Failure to do so is likely to breach a patient's human rights and for families, discovering a DNR has been imposed on a loved one can be completely devastating. This unlawful practice must end."

An NHS England spokeswoman said: "We welcome the results of this audit, which we commissioned, and which shows there has been some improvement in the care provided.

"But there is clearly more that can be done.

"Although this audit presents a snapshot of end-of-life care within NHS hospitals, there are clear variations in the support and services received across hospitals and areas where improvements must continue to be made."