A privately-run surgery unit that had until Tuesday to put in place a series of improvements recommended by a health watchdog has been under fire from patient relatives and hospital staff.

The Lister Surgicentre, which has a five year contract to carry out routine NHS surgery, was warned by the Care Quality Commission to improve its standards of care, after an unannounced visit in February. Inspectors found patients were not being prioritised or treated within government recommended time-frames, training was lacking and insufficient numbers of staff were available at times.

Clinicenta, the operator of the service which opened on the Lister Hospital site last September, said it had made significant improvements since the visit.

But this week an anonymous Lister Hospital staff member called the operation a “shambles”, citing a lack of training for staff and managers and problems with making appointments and following up operations.

“Some patients have had to remove their own casts, and one woman has had her skin grow over a cast and needs an operation to remove it,” they said.

A woman who did not want to be named was angry that her mother had been left in limbo during a course of treatments to improve her sight.

“We have yet to ascertain whether my mother has been left too long for a third injection and will have to have all three again, or whether the delay in the third injection will have ruined her sight forever,” she said.

“The frustration for an 80-year-old recently widowed woman has done nothing but cause additional unnecessary stress.”

A Clinicenta spokesman said it could not comment on individual cases because of patient confidentiality, but added the company has taken a range of actions to address the issues raised by CQC.

“We recognise that some patients continue to have difficulty in getting appointments and apologise for the distress that this causes. Clinicenta remains committed to providing patients with high quality care and will continue to work with the NHS to make sure that the necessary staff are available.”

The CQC will make an unannounced inspection to determine if things have improved at the centre. If improvements are not made, the commission has the power to restrict, suspend or cancel services, issue fines and prosecute providers.