The NHS wastes the equivalent of one entire hospital each year by admitting patients unnecessarily for operations.

The British Association of Day Surgery has said too many patients are still staying overnight in hospital when they could be treated in just a few hours during the day.

A report by the Audit Commission published last year suggested the NHS could carry out over 120,000 more operations each year if more people were treated as day cases.

Thousands of bed days could be saved if day surgery was properly used

David Ralphs, BADS president

The government launched a drive earlier this year to encourage hospitals to do more day surgery in an effort to cut waiting lists.

Last year's report found 264,000 "bed days" were lost through this type of inappropriate admissions.

According to BADS, this represents the equivalent of 723 beds - the capacity of a large district or general hospital.

More day surgery

The BADS and Audit Commission has published a list of 25 operations that should be carried out as day cases.

These include tonsillectomy, hernia and varicose vein operations.

The association said some hospitals had simply failed to change the way they work.

Many continue to admit patients in the evening, perform surgery the following day and send them home the day after.

David Ralphs, president of BADS, said the situation needed to change. He suggested patients could help the NHS to modernise.

"Patients must learn to ask if their operation could be undertaken as a day case. Surgeons must learn to offer."

Mr Ralphs said the NHS and patients would benefit if more people were treated as day cases.

"Thousands of bed days could be saved if day surgery was properly used and patients would have the opportunity to recover in their own homes rather than in a hospital ward where, sadly, there is also the risk of infection."

Mr Ralphs added that many hospitals had failed to implement new government guidelines on day surgery and were still admitting patients unnecessarily.

"It is very disappointing that hospitals are still reluctant to change their ways," he said.