EIGHT operations in the Lothians are cancelled every week because of equipment failures, bed shortages and staffing levels, it has emerged.

In the last year, 420 elective procedures were cancelled, a significant rise on previous years.

The ERI suffered the most cancellations, with hundreds also being postponed at the Sick Kids, the Western General and St John's Hospital in Livingston. Critics said not enough bed space was provided in hospitals for times of need, although NHS chiefs pointed out that the cancellations equated to little over 0.5 per cent of all operations in the area – 65,000 operations in total were carried out last year.

Figures released under the Freedom of Information Act detailed the cancellations across the five Lothians hospitals where elective operations take place.

They come a day after the Evening News revealed plans by NHS Lothian to site a temporary mobile operating theatre in one of the car parks at Little France to drive down waiting lists.

Eight beds and one operating theatre would be provided for the ERI in a bid to ease waiting times for treatment.

One source at the ERI said: "It's all to do with a lack of beds. There was a Monday not so long ago when 19 operations were cancelled because there were no beds whatsoever. Consultants come up and ask me what's going on because they can't believe it.

"It's not an old problem. There were 1500 beds at the old ERI and 800 at this one – it is obvious what would happen."

The figures are up from 196 in 2007, however, in that period the new TRAK recording system used to monitor cancellations was not operational in St John's, and only used for half the year in the Sick Kids. Despite this, the numbers indicate that a rise was still evident. Cancellations were all as a result of a lack of beds, staffing, no resource or equipment breakdown.

Margaret Watt, chairwoman of the Scotland Patients Association, said: "This is totally unacceptable. To have more than one person a day, who's been on a waiting list, have a procedure cancelled is not on, and it knocks waiting lists even further back.

"We are short of beds, short of nurses and now it seems we are short of operating theatres."

James McCaffery, NHS Lothian's chief operating officer of acute services, said: "We were able to record the number of cases in only two sites in 2006, but the figure had increased to five within two years. As a result, the numbers of rescheduled procedures rose between 2007 and 2009, not because of an increase of cases but because of more efficient and universal recording method.

"A total of 190,711 elective procedures were carried out between 2006 and 2008 in NHS Lothian and, unfortunately, 802 had to be rescheduled during these three years. This was caused by a variety of different reasons, but in every case, another appointment was arranged at the patient's earliest convenience."