Bad idea. There is already too much bureaucracy in the Medicare and Medicaid programs.
It seems like anytime the government gets involved in anything, there are too many bureaucrats involved and they lose sight of what the program was for in the first place.
Example: Social security. It was first implemented to help retirees live comfortably in their retirement. There was something like 35 people contributing to the fund for each 1 person collecting. Today, it's 1 person collecting for every 2 or 3 contributing and the still don't have enough money to afford everything they're handing out. The program keeps expanding, but the revenue can't possibly expand fast enough to keep up with the costs.
Would you rather have a bureaucrat or a doctor decide on what treatment is best for your illness? I have already been the victim of HMO decisions based on saving money rather than what's best for the patient.
The government can't afford the programs we have now. How are they going to afford national health care? If we keep running trillion+ dollar deficits, pretty soon interest on the debt with be the government's largest expense. There's no way you would run a business or household with that kind of fiscal irresponsibility, the government shouldn't be run that way either.