Below is from AMA CPT Changes 2009
"Codes 64416, 64446, 64448, and 64449 were all revised to eliminate subsequent days of daily management for these codes. Previously, the descriptors for these codes included language that identified reference to the inclusion of ". . . daily management for anesthetic agent administration." The change was made largely due to the shift in the site of service for these procedures as these procedures are no longer performed predominantly in the inpatient setting. The change regarding the site of service for this procedure inherently affects the follow-up efforts for this service and, as a result, the language identifying inclusion of follow-up days for these procedures has been removed."