National incidence of use of monitored anesthesia care

Abstract

Background: Sedation or monitored anesthesia care (MAC), alone or after peripheral regional nerve block, is currently administered by anesthesiologists and/or certified registered nurse anesthetists. Some of this care may be at risk for substitution by other providers or by reductions in reimbursement.

Methods: Data from the 2006 United States of America National Survey of Ambulatory Surgery were analyzed to determine national rates for the percentage of total ambulatory anesthesia operating room (OR) time that was either (1) sedation and/or MAC, or (2) peripheral regional nerve block with/without sedation or MAC.

Results: MAC cases alone comprised 29%± 2% of OR time with an anesthesiologist and/or certified registered nurse anesthetist. MAC and/or peripheral block comprised 34% ± 2% of OR time. Percentages by cases were larger than by OR time (P < 0.0001). Among cases with anesthesia, 42% ± 3% were MAC and 47% ± 2% were MAC with/without peripheral block. Percentages of American Society of Anesthesiologists' Relative Value Guide units for MAC would be intermediate between the 29% and 42%, and for MAC and/or peripheral block between the 34% and 47%.

Conclusions: MAC alone or after peripheral nerve block accounts for a relatively high percentage of ambulatory anesthetics nationwide.