The revised conversion factors for use in calculating payment for anesthesia services (procedure codes 00100 through 01999) for service dates January 1 through February 29, 2012, are as follows:
Participating Physician Nonparticipating Physician
The conversion factors for non-medically directed certified registered nurse anesthetists (CRNAs) are identical to the participating physician anesthesia conversion factors for each payment locality.
The conversion factors for medically directed CRNAs (for both physician medical direction and medically directed CRNAs) are based on 50 percent of the sum of the anesthesia base units and time units, multiplied by the appropriate participating physician locality conversion factor (i.e., 50 percent of the sum of (base units + time units) x locality conversion factor = anesthesia allowance). The medical direction 50 percent payment policy applies if both a CRNA (or anesthesia assistant) and an anesthesiologist are involved with the same case.
Limiting charge for anesthesia
The limiting charge for unassigned anesthesia services is determined as follows:
Step 1: Determine the allowance for the anesthesia service.
Use this formula for physician personally performed services:
(base units + time units) x nonparticipating physician locality conversion factor.
Use this formula for the physician’s claim for physician medical direction services —
[.5 x (base units + time units)] x nonparticipating physician locality conversion factor.
Step 2: Multiply the result of the above calculation by 1.15 to determine limiting charge.
Note: Limiting charge does not apply to CRNA or anesthetist claims; assignment is mandatory on these claims.