Primary care staff will be expected to lower the weight of obese patients awaiting an operation, stop them smoking, as well as stabilising and ‘correcting' long-term conditions such as asthma and diabetes.

The plans are part of the Quality, Innovation Productivity and Prevention (QIPP) scheme the DoH hopes will slash billions from NHS costs in the next decade.

GP leaders attacked the plans, arguing that GPs already do as much as they can to optimise patients' health.

But several English hospitals have already adopted the Enhanced Recovery Programme (ERP), pioneered in Denmark.

It has been shown to cut length of stay from 16 to three days for colorectal surgery, according to the DoH.

The schemes are due to be evaluated and applied in more areas this year, and discussions are underway as to how to involve primary care. NHS discussion papers suggest practice nurses will be heavily involved ‘pre- and post-op' and there will be greater communication between GPs and hospital staff about patients' condition.

Slides from a presentation by ERP national clinical lead for England Mr Alan Horgan acknowledge there will be ‘barriers'. ‘Some say [cutting length of stay to 3-4 days] is inhumane,' one slide says.

Another presentation from an ERP event says: ‘The patient must be in the best possible condition for surgery - for example, identify if anaemia, hypertension and/or diabetes is present, and correct it, ideally by the GP prior to referral.'

Managers acknowledge that GPs should receive a proportion of the savings generated in secondary care. Paul Carroll, assistant director of NHS Ashton, Wigan and Leigh, suggested in a presentation last year that PCTs ‘incentivise GP involvement through the QOF structure or practice-based commissioning funding'.

Other suggestions by managers to engage general practice include ‘visits to GPs from secondary care' and ‘referral [of pre/post-op patients] to practice nurses rather than GPs'.

GPC chairman Dr Laurence Buckman called the enhanced recovery programme ‘ridiculous,' saying that GPs already did as much as they could to optimise patients' health.

‘This doesn't sound like any doctor has had any part in this. It's an idea an accountant would have,' he said.

‘Our whole profession is about optimising people's health anyway. You can tell someone they are fat and how to lose weight or advise them to stop smoking, but they have to do it themselves.'

Dr Buckman said improving communication with consultants would benefit patient care, but warned ‘there is usually a reason patients are kept in hospital.'

But RCGP chairman Professor Steve Field said there was more GPs could do to improve patient's health before an operation, but they would require better access to services like dieticians.  ‘GPs have a role to play because they have that overview of the patient,' he said.

The DoH said it had no plans to make it easier for PCTs to end GP contracts in order to speed up progress towards QIPP efficiency targets, after reports PCTs were seeking an extension of their powers.