Anesthesia coding - an Anethesiologist


Lynbrook, NY
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Can anyone help on this?

When coding Anesthesia service done by an Anethesiologist; for a colonoscopy and endoscopy, should a modifier be used to identify the two procedures done? And how would that be coded? Anesthesia time was 30 mins.
Start with CPT 45378 for the colonoscopy. Hopefully you have a crosswalk to determine the correct anesthesia code. You'll need more info regarding the endoscopy to verify whether or not that procedure carries a higher base unit value. Use your physical status modifier (P1-P5). You find the highest base value and then report your time units for the entire service. You don't report both services, only the higher valued one since the patient is under anesthesia no matter what the surgeon is doing. If the patient has co-morbidities that increase the anesthesiologists risk (i.e. HTN, diabetes, heart problems, etc.) you can add units for the P3-P4 modifier.
Hi, Commercial Ins. and Medicaid (depending on your state's policy) DO PAY P1-P6 physical status modifier (where they have a certain # of units value) but Medicare Does NOT recognize this modifier, Instead when billing for Medicare they require modifier AA to indicate that the anesthesiologist provided the service, QY - Medical direction of one certified registered nurse (crna) anesthetist by an anesthesiologist OR QZ - CRNA service without medical direction by a physician.
Colonoscopy:45378 (5 units) + P3=2 (units) when billing for BC/BS= 7 UNITS.
Colonoscopy:45378 (5 units) AA (no value) when billing for Medicare= 5 UNITS.
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Anesthesia time billing

I have been told that you may bill a time unit for every 15 minutes (and can add one additional unit for any extra minutes over 5). I was also told that after 4 hours you may bill for a unit every 10 minutes. I am looking for reference(s) regarding this rule. I am coding in California. Can someone help clarify this and let me know where I may read about this? Thanks,

Coding in California