Specialty
Anesthesiology Billing and Revenue Cycle Management
Base unit formulas. Concurrency modifiers (AA, QK, QX, QZ). ASA Physical Status. Exact time tracking.
Why it’s different
Anesthesia billing operates on a unique mathematical formula: (Base Units + Time Units + Physical Status Units) multiplied by the payer's Conversion Factor.
Concurrent care rules determine split billing between Anesthesiologists and CRNAs (Modifiers AA, QK, QX, QZ), where improper modifier selection triggers instant 50% revenue loss or compliance audits.
Common challenges
Where the money goes missing.
- ASA Base Unit Assignment
- CPT 00100–01999 crosswalk errors resulting in incorrect base unit calculation before time is applied.
- CRNA & Physician Concurrency
- Incorrect medical direction modifiers (AA, QK, QX, QZ, QY) causing concurrency audit rejections.
- ASA Physical Status Modifiers
- Failure to report P3, P4, or P5 physical status modifiers that yield additional billable base units.
- Qualifying Circumstances
- Omitting emergency (99140), extreme age (99100), or controlled hypotension (99135) unit add-ons.
- Exact Anesthesia Time Tracking
- Discrepancy between start/stop times in clinical anesthesia logs and billed minute units.
How we help
We calculate base units using official ASA Relative Value Guides, audit exact start-to-stop time minutes, apply correct concurrency and physical status modifiers, and capture qualifying circumstance unit add-ons.
Our team audits anesthesia records daily to protect your practice against underpayment and billing compliance exposure.
Key codes
- ASA Base Units (00100–01999)
- Modifiers AA, QK, QX, QZ
- Physical Status P1–P6
- Qualifying CPT 99100–99140
Indicative, not exhaustive. Code sets and payer policies change.
Get an Anesthesia Billing Audit
Send us a sample of your denials. We'll tell you what's actually driving them in your specialty.