Why does there even need to be a bill (in the sense of keeping track of costs on a per-patient basis) to begin with?

Because doctors need to pay their student loans? Because IV fluids need to be clean and put in bags? Because no single patient’s care is standardizable? Maybe theres guidelines and standards of care, but biology is too messy for cookie-cutter care.

Paying the doctor a salary doesn’t require itemizing the costs by patient. All the government really needs to know is the total aggregate demand in order to employ the correct number of doctors, not which patient required what care.