The former chief executive of United Bristol Healthcare trust has appealed to the Bristol Royal Infirmary inquiry to find a way of preventing similar tragedies without depriving high-risk patients of treatment.

At the end of his second appearance at the inquiry, Dr John Roylance said that as the father of four children and grandfather of six, he understood 'the tragedy of the loss of a child very acutely'.

'I very much regret that nobody ever made it known to me that the service was not merely ripe for improvement and requiring improvement but was thought to be unacceptable, ' he said.

'I do not look to the inquiry to exonerate me - I am unimportant in this - but I do hope they will be able to find a way of preventing this happening without the very real risk. . . of some patients not being treated lest a poor outcome produces some improper criticism.'

Inquiry chair Professor Ian Kennedy responded: 'We have heard what you say and will do our best to do exactly that.'

Dr Roylance said he was particularly concerned that Down's syndrome babies with high-risk heart disease would be deemed inoperable.

Statistical analysis for the inquiry has shown that Bristol carried out a greater number of Down's syndrome cases between 1984 and 1995 than other centres.

Oral evidence sessions at the inquiry into the deaths of babies who underwent complex heart surgery at Bristol Royal Infirmary in the 1980s and early 1990s end tomorrow. Over the past three weeks, evidence has been taken from the three doctors struck off or disciplined by the General Medical Council in 1998.

Surgeon Janardan Dhasmana, who was disciplined, broke down in tears as he told the inquiry he had been 'ruined' by the tragedy.

An independent report into paediatric cardiac surgery at Bristol in 1995 found Mr Dhasmana would 'compare very favourably with the best UK institutions' on three key procedures. It said former medical director James Wisheart would 'be amongst the highrisk surgeons'.

Mr Wisheart said he stopped carrying out 'switch' operations - one of the procedures at the centre of the investigations - as the volume of cases was low and it was more 'appropriate' for the younger Mr Dhasmana to do them.

He acknowledged that his results in another key operation, atrial ventricular septal defects (AVSD), were 'disappointing' and said: 'The one thing I regret is that I did not sit down with my colleagues and draw their attention to this issue.'

He admitted that Dr Roylance asked him to comment on a letter sent by professor of cardiothoracic surgery Gianni Angelini to Dr Peter Doyle, a senior medical officer at the Department of Health, in 1994. Dr Doyle had raised concerns with him after talking with whistleblower Dr Stephen Bolsin.

Professor Angelini said the department was aware of problems in one procedure (switches). He said the appointment of a new surgeon and steps to end split-site working should address them.

Mr Wisheart said he stopped AVSD operations 'perhaps a month later'.

Seven children died in the last eight such operations he performed.

Dr Roylance told the inquiry he did not know there were disputes among clinical staff about death rates until 1995.