start with the CPT book, prolly have to pay for a "Sheet" if it's worth its salt.
which sort of Dr r u coding for? if it's an anesthesiologist, you're looking at the P1-P6 modifiers, the qualifying circumstances 99100-99140, on page 52 of the CPT book. you're doing (base unit + time + modifying factor) * Conversion factor. (have to check what the CF is, it's .35 something maybe). also you're looking at the modifiers, based on if it's an anesthesiologist who is handling the anesthesia? is the MAC being done by a CRNA under a anesthesiologist, or under a different sort of physician? there are those modifiers, can get you those easy.
also, are you looking strictly for the anesthesia codes? the anesthesia codes for radiological procedures are on page 59 of the AMA CPT book. the codes for intrathoracic are on page 55. correct me if i'm wrong but the codes are usually very strictly related to the anatomical region that a surgeon is working on.
you may want to take your time, if the code says "or" versus "and" for the particular anatomical location that the code pertains to. if it says "and" it's a safe bet that ALL those locations must be related to the code. if it says "or" it's a choice of locations.
so, what anatomical region, specifically, are the stents and embolization occuring in? go from there, if you haven't already.
best luck