If an anesthesiologist is medically directing more than four CRNAs, the Medicare regulations indicate that the service must be billed as medically supervised as opposed to medically directed anesthesia services. The anesthesiologist should bill with the AD modifier and the CRNA should bill with the QX modifier. The Medicare payment to the CRNA would be 50 percent of the Medicare allowable amount for the procedure. Payment to the anesthesiologist will be based on three base units per procedure when the anesthesiologist is involved in furnishing more than four procedures concurrently or is performing other services while directing the concurrent procedure. An additional time unit can be recognized if the physician can document he was present at induction.
If anesthesiologists are in a group practice, one physician member may provide the pre-anesthesia examination and evaluation while another fulfills the other criteria. Also, one physician member of the group may provide post-anesthesia care while another member of the group furnishes the other component parts of the anesthesia service. However, the medical record must indicate that the physicians furnished the services and identify the physicians who rendered them.
Periodically, physicians will be required to submit documentation showing the names of the anesthetists directed and procedures performed for selected claims. If a physician is unable to supply the necessary documentation for the sample claims, he may be referred for pre-payment or post-payment auditing.