The NHS National Programme for IT (NPfIT) is now so well advanced that the health service “could no longer function” without it, the government has said.

Exchequer secretary to the Treasury Angela Eagle told MPs last week that NPfIT is a success despite delays implementing key aspects of the strategy, including the Lorenzo next-generation hospital administration package.

"Without the programme, the NHS could no longer function, and it is providing essential services and significant benefits to tens of thousands of clinicians and millions of patients," she said.

Eagle was replying to a Commons debate on a series of reports from the Public Accounts Committee (PAC) on government computing disasters.

Conservative MP Richard Bacon highlighted the PAC report on the NHS which said that Lorenzo - on which three-fifths of the programme was said to depend - was not yet available despite a claim in supplier iSoft's 2005 annual report that it was.

He said a Treasury minute had stated the software was not expected until 2008 and he asked that a minister announce its arrival in Parliament when it happens.

But Eagle said NPfIT "is a success story that ought to be acknowledged".

"More than 5.5 million appointments have now been made using the Choose and Book system, representing 44 per cent of first referrals,” she said.

"In addition, 397 million diagnostic images are now stored centrally, and 42 million electronic prescriptions have been used in a service that is now available in 41 per cent of pharmacies and 47 per cent of GP surgeries.

"Nearly 400,000 users are registered to use the NHS care records spine, with 45,000 NHS staff accessing it daily."

Eagle said national leadership had been strengthened by the appointment of a chief clinical officer and national clinical leads.