Will I Be Awake? Understanding the Levels of Sedation

Anesthesia is not a single switch. The ASA describes a continuum of depth of sedation with four named states: minimal sedation (anxiolysis), moderate sedation/analgesia — commonly called conscious sedation — deep sedation/analgesia, and general anesthesia.¹

At a minimal level you are relaxed but awake and respond normally to verbal commands. Under moderate sedation you respond deliberately to verbal stimulation, and your breathing and heart function are unlikely to need assistance. Under deep sedation you cannot be easily aroused, may respond only after repeated or painful stimulation, and your breathing and heart function may need support. General anesthesia is a drug-induced loss of consciousness from which you cannot be aroused, even by painful stimulation, and the ability to maintain breathing independently may be lost.¹

Why the levels can shift

Because sedation is a continuum, it is not always possible to predict how an individual patient will respond. The ASA states that practitioners intending to produce a given level of sedation should be able to rescue patients whose level becomes deeper than intended, and that it is not appropriate to continue a procedure at an unintended level of sedation.¹

What you may remember

Memory differs by level. Under minimal and moderate sedation many patients remember parts of the procedure in patches; under deep sedation and general anesthesia, most remember nothing. Your anesthesiologist watches your responses continuously and adjusts the medication throughout.

Why the plan is individual

The same dose can act differently in different people. Age, body weight, other medications, alcohol use and conditions such as sleep apnea all change how sedation affects you, which is why the pre-procedure assessment asks about them — and why the ASA's sedation guidelines require that assessment before the procedure begins.²

Standards require that practitioners be able to rescue patients whose level becomes deeper than intended, and the anesthetic plan should include the personnel and equipment needed to respond to a change in depth. Ask which level is intended for you, and what the plan is if it changes.

Sources

1. American Society of Anesthesiologists. Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia. Original approval October 13, 1999; last amended October 23, 2024.
2. Practice Guidelines for Moderate Procedural Sedation and Analgesia 2018: A Report by the American Society of Anesthesiologists Task Force on Moderate Procedural Sedation and Analgesia. Anesthesiology. 2018;128(3):437–479.