Anonymous Cosmetic Surgery

I'd like to know if undergoing a cosmetic surgery anonymously
is possible in US, if not any other countries?

I'm thinking just use an assumed name when I visit the hospital,
but I'm not sure if they would obligate me to show the identification
in order to proceed with the surgery.

I'm using my own fund, not insurance, so it shouldn't be a problem,
but I would like to know for sure.

Has anyone done this? If so please tell me anything
I should know to make sure no one would find out that
I had undergone the surgery by not even telling my
identity to the doctor.

If it's possible, what kind of payment method should I
use to make sure it's 100% anonymous?

Please tell me the details!

Thank you very much for your support..