Defined by Medicare, an anesthesiologist’s involvement with a certified registered nurse anesthetist (CRNA) or anesthesiology assistant (AA) in one, two, three, or four concurrent procedures where the anesthesiologist is physically present and where all the seven requirements are met and documented. Medicare does not recognize medical direction by the anesthesiologist if he or she is involved in more than four concurrent procedures. When the anesthesiologist takes on five or more cases, he or she is supervising or has failed to meet the medical direction requirements, with a few exceptions [Medicare Carriers Manual, Section 4830].