Critical: Confirm You Are Formally "Admitted" — Not Under "Observation Status"
Even if you sleep in a hospital bed overnight, if the doctor writes "Observation Status" instead of a formal inpatient admission order, your stay is billed under Part B (outpatient) — not Part A. This means the Part A deductible logic does not apply, and you may owe 20% of all services with no cap.
Observation status also does not count toward the 3-day qualifying stay required for Skilled Nursing Facility (SNF) coverage.
Before surgery, ask your surgeon and the hospital admissions team:
"Will I be formally admitted as an inpatient, or under observation status?"
After surgery, you will likely receive 3–5 separate bills from different providers: the hospital, your surgeon, the anesthesiologist, the radiologist (for imaging reads), and possibly a pathologist or lab.
Do all your doctors accept Medicare assignment?
Medicare pays 80% of the approved amount. If a doctor does not accept Medicare assignment, they can charge up to 15% more than Medicare's approved rate — and you pay that extra amount out of pocket. This applies to your surgeon, anesthesiologist, and assistant surgeon.
Will you use an assistant surgeon?
Medicare covers 1 assistant surgeon. If more than one is used, you may be billed for the extra.
What brand and grade of implant will you use?
Medicare covers standard implants. If your surgeon uses a premium implant (e.g., custom-fit or higher-grade metal), you may pay the difference.
What medical supplies will be used, and are any extra-cost?
Most surgical supplies are bundled into the hospital bill. But some items — like specialized bone cement, a continuous passive motion (CPM) machine, or a cryo-therapy unit — may not be covered.
Will this be inpatient or outpatient? Why?
Inpatient (Part A) vs. outpatient (Part B) affects how much you pay. Outpatient can sometimes cost more out-of-pocket. 'Observation Status' is billed as outpatient under Part B — even if you sleep in a hospital bed overnight. This means your Part A deductible does NOT apply, but you pay 20% coinsurance on every service, and your meals and some medications may be billed separately. Critically: if you are placed under Observation Status, it does NOT count toward the 3-day inpatient stay required to qualify for Medicare-covered Skilled Nursing Facility (SNF) care after discharge.
Which anesthesiologist will be used — and do they accept Medicare assignment?
Even if your surgeon accepts Medicare assignment, the hospital may assign an anesthesiologist who does not. A non-participating anesthesiologist can legally charge up to 15% more than Medicare's approved rate (the 'Limiting Charge'), and you are responsible for that extra amount. This is a legally permitted extra charge — it is not a billing error. With Original Medicare, you have no network restrictions, but you can still face this limiting charge from any non-participating provider.
How long is the surgery expected to take? How does that affect my anesthesia bill?
Anesthesia is billed in 15-minute time units. A 90-minute surgery = 6 time units. The Medicare conversion factor ranges from ~$19.42 (rural areas) to ~$23.37 (NYC suburbs) per unit — your locality matters. An unexpectedly long surgery can significantly increase your anesthesia bill.
Who bills for anesthesia — the anesthesiologist, a CRNA, or both?
A Certified Registered Nurse Anesthetist (CRNA) supervised by an anesthesiologist can result in two separate bills — one from each provider. Medicare has specific rules about medical direction that affect payment rates.
Will I need a Skilled Nursing Facility (SNF) after surgery?
SNF is only covered if you have a qualifying 3-day inpatient hospital stay first. Days 1–20 are free; days 21–100 cost $217/day.