Question Prior Authorization

dade city, FL
Best answers
I am wondering if you are getting authorization for a procedure but you are unsure of the exact code you need do you get the higher paying code authorized and are lower paying codes covered under this authorization.

For example:

My physician states he is ordering a echocardiogram so we get authorization for 93306 but it ends up being a limited echo so we bill 93308 instead. Is 93308 now covered under the authorization for 93306?
We get authorization for 37231 (PTA with Stent and Atherectomy of Tibial/Peroneal) but during the procedure the physician only does a 37229 (PTA with Atherectomy Tibial/Peroneal). Is the 37229 now covered under the authorization with 37231?

I've always heard on authorizations you should up code because you can always bill down but not up but we have been receiving denials lately for these type of situations and it is only happening with procedures/testing the insurance companies do not deny claims that have a auth for 99205 when we bill 99204/99203 or 99215 and we bill 99214/99213. I'm wondering how this works for others and what work flow would best assist us in this area.

Thank You