The health secretary has survived a no-confidence vote brought by the Tories over her handling of the NHS.
Mrs Hewitt has faced calls for her to quit
A majority of 63 ensured Patricia Hewitt will not have her salary cut - a traditional way of showing no confidence in a minister.
Conservative leader David Cameron had accused Tony Blair of "hanging his health secretary out to dry".
The PM's spokesman said he retained his confidence in her, but her future was up to his successor Gordon Brown.
During lively exchanges at prime minister's questions, Mr Cameron said: "Everyone in the NHS and everyone in the country will notice that he is hanging his health secretary out to dry.
"Doesn't he realise the damage it does to have a lame duck health secretary?"
He also urged Mr Blair to abandon changes to maternity units and accident and emergency departments.
But Mr Blair said the government was being advised by people who knew better than Mr Cameron how to deliver health care.
He added: "I will not consider abandoning the programme at all, or the NHS."
The prime minister's official spokesman was later asked whether the premier retained confidence in Ms Hewitt and replied: "Absolutely."
The no-confidence vote in the Commons follows criticism of the applications system introduced to reduce the time taken by junior doctors to train as consultants.
Many medics have complained they were not selected for their first-choice NHS trusts, or did not get an interview.
Mrs Hewitt has apologised for the system's failings, but has refused calls to resign.
Opening the debate ahead of the no-confidence vote, shadow health secretary Andrew Lansley said: "The staff in the NHS have reached the end of the line with the secretary of state.
"Serial incompetence and a failure to listen... mean she has no credibility left."
He added: "Even were she to remain as secretary of state after a change in the prime minister, she cannot command the confidence and support across the National Health Service which is needed."
Mr Lansley said the number of NHS staff had fallen under Ms Hewitt and that the introduction of primary care trusts had been "botched".
Ms Hewitt received support on the front bench of the Commons from several members of the Cabinet, including International Development Secretary Hilary Benn, Communities Secretary Ruth Kelly, Trade Secretary Alistair Darling, Labour chairman Hazel Blears and Pensions Secretary John Hutton.
She said: "The most important judgement, the single most important test of the NHS, are the patients who use it every day of the year."
A survey had shown most patients found their care to be good, very good or excellent, she added.
Ms Hewitt also welcomed the High Court's decision to reject the judicial review brought by junior doctors over training posts.
She said she was looking carefully at the comments made by Mr Justice Goldring and promised a statement to MPs on Thursday on "how we will fulfil our responsibilities to trainee doctors".