A surgeon at a crisis-hit hospital who left a swab inside a patient following an operation was not disciplined over the serious error, it has emerged.  

A Freedom of Information Act disclosure to the Guardian revealed a clinician in the gynaecology department at Whipps Cross was only spoken to when the mistake emerged.

The hospital, which is in special measures over serious failings in care, classified the incident as a 'never event', which is an error which could cause serious harm or death. 

The only other never event at Whipps in the two years up to April involved a pain relief injection to the wrong side of a patient's back. 

Neither patients were harmed as a result of the errors.    

However, the debt-ridden trust which runs Whipps, Barts Health, has seen a further six never events across its four other hospitals.   

There were five such incidents at The Royal London Hospital in Whitechapel, with one causing 'serious harm' to a patient.  

This happened when a neurosurgeon operated on the wrong place of a patient's body during surgery for Cauda Equina syndrome, a serious condition causing extreme pressure and swelling of nerves at the base of the spinal cord.  

Two patients each had the wrong tooth removed at Royal London, while a swab was left inside a patient following surgery in the Trauma and Orthopaedics Unit.  

At Newham University Hospital, a patient had the wrong side of their chest drained, which was said to have caused 'low harm'.  

Barts Health refused to reveal any further details of the incidents, claiming this could compromise patient confidentiality. 

Referring to the incidents at Whipps Cross, a Barts Health Trust spokeswoman said: "We have offered our sincere apologies to the patients involved and held thorough investigations into the incidents.  

"Our investigations found that neither patient came to physical harm, and we have made improvements to our processes in a concerted effort to prevent the incidents from happening again, including how care records are documented. 

"No member of staff was disciplined." 

"Staff involved were met by senior management to discuss the incident, identify any additional training needs and were reminded about Trust policies to ensure the safety of all patients."