It became effective as of July 2011 and now reads: “During regional anesthesia (with no sedation) or local anesthesia (with no sedation), the adequacy of ventilation shall be evaluated by continual observation of qualitative clinical signs. During moderate or deep sedation, the adequacy of ventilation shall be evaluated by continual observation of qualitative clinical signs and monitoring for the presence of exhaled carbon dioxide unless precluded or invalidated by the nature of the patient, procedure, or equipment.”

Rather than supported by the highest level of evidence-based Class A, Level 1 scientific data, this amendment was a consensus document initiated by the ASA Committee on Standards and Practice Parameters, approved by the ASA Board of Directors, and passed by the October 2010 ASA House of Delegates with supposedly little debate. This new standard makes perfect sense for medical anesthesiologists, particularly those who are based in hospitals, because it costs them essentially nothing to obtain this sometimes very valuable information.

Because in most instances ASA physician anesthesiologist members provide moderate and deep sedation in the same operating rooms as they do general anesthesia, they already have the equipment to monitor EtCO2, and they already routinely use nasal cannula O2 for their sedations. All that is really needed for them to meet this mandate is to either exchange their O2 cannulas for those with a CO2 sampling port for connecting to their EtCO2 monitor or to insert an intravenous catheter into a standard O2 cannula and connect it to monitor.

To complicate this far-reaching ASA requirement, the Centers for Medicare and Medicaid Services (CMS) in 2009 and 2010 rewrote their CMS Hospital Conditions of Participation and Interpretive Guidelines that govern anesthesia services. The CMS mandated that all anesthesia services in a hospital be organized by a qualified physician and consistently implemented in every hospital department and area where “anesthesia services” are rendered. However, as opposed to the ASA standards, the CMS definition of “anesthesia services” excludes topical and local anesthesia, minimal sedation, moderate sedation/analgesia (conscious sedation), and labor epidural analgesia. Thus, even though the CMS does not require standardization of any monitoring, including EtCO2, throughout the hospital for moderate sedation, because the ASA standards require anesthesiologists to monitor EtCO2 for all of their moderate sedations, the ASA believes that other less qualified, nonanesthesiologist sedation practitioners need it even more than their members to enhance their margin of safety. Therefore, if an ASA member is the hospital's “physician in charge of anesthesia services,” he or she may have little choice but to require the monitoring of EtCO2 in all hospital areas where moderate sedation is administered if it is required in the hospital's operating rooms.