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Monitored anesthesia care in adults

Eric B Rosero, MD
Section Editor
Girish P Joshi, MB, BS, MD, FFARCSI
Deputy Editor
Marianna Crowley, MD


Monitored anesthesia care (MAC) is a type of anesthesia service in which an anesthesia clinician continually monitors and supports the patient's vital functions; diagnoses and treats clinical problems that occur; administers sedative, anxiolytic, or analgesic medications if needed; and converts to general anesthesia if required. Approximately one-third of ambulatory anesthesia services for diagnostic or therapeutic procedures in the United States are provided as MAC [1], often in out-of-operating-room locations.

This topic will discuss preoperative evaluation for patients who will receive MAC, monitoring during MAC, and the medications and sedation techniques commonly used during MAC. Procedural sedation by non-anesthesia clinicians and the drugs and techniques used for general anesthesia are discussed separately. (See "Procedural sedation in adults outside the operating room" and "Overview of procedural sedation for gastrointestinal endoscopy" and "General anesthesia: Induction" and "General anesthesia: Maintenance and emergence".)

Sedation during procedures for which the primary anesthetic is a regional anesthesia technique, either neuraxial anesthesia or peripheral nerve block, is not considered MAC. However, the basic principles of sedation that are discussed here apply to those anesthetics as well.


A medical history and anesthesia-directed physical examination should be performed for all patients who undergo anesthesia, including those having monitored anesthesia care (MAC).

Patient medical status — The goals for preoperative evaluation are to identify underlying medical and physical conditions that may increase risk and to create an anesthetic plan that minimizes risk. In anticipation of MAC, the patient should be evaluated for conditions that increase sensitivity to sedative and analgesic medications (eg, older age; obstructive sleep apnea; advanced chronic lung disease; pulmonary hypertension; coronary, liver, or renal disease; anxiety disorders; chronic pain; use of opioids, sedatives, or recreational drugs) to allow appropriate drug dosing and administration.

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Literature review current through: Nov 2017. | This topic last updated: Aug 29, 2017.
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