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    Chief Complaint


    Organ System


    Patent Pending

    Richmond Agitation-Sedation Scale (RASS)

    Ranks agitation and possibility for sedation.


    See Evidence for definitions of criteria.
    When to Use
    Why Use

    The RASS can be used in all hospitalized patients to describe their level of alertness or agitation. It is however mostly used in mechanically ventilated patients in order to avoid over and under-sedation.

    • The Richmond Agitation and Sedation Scale (RASS) is a validated and reliable method to assess patients’ level of sedation in the intensive care unit.
    • As opposed to the Glasgow Coma Scale (GCS), the RASS is not limited to patients with intracranial processes.
    • RASS is mostly used in the setting of mechanically ventilated patients in the intensive care unit to avoid over- and under-sedation.
    • A RASS of -2 to 0 has been advocated in this patient population in order to minimize sedation. This strategy has been shown to reduce mortality, and to decrease the duration of mechanical ventilation and the length of stay in the ICU.
    • The RASS is different than the levels of sedation/analgesia used by the American Society of Anesthesia (minimal, moderate, deep, general), and the two should not be used interchangeably.
    • Mechanically ventilated that are deeply sedated (RASS of -3 or less) have been shown to remain intubated and mechanically ventilated for longer periods of time. This in turn leads to longer ICU stays and higher mortality.
    • Similarly, mechanically ventilated patients that are too agitated are at risk of self-extubation and of ventilator dyssynchrony.
    Very agitated
    Alert and calm
    Light sedation
    Moderate sedation
    Deep sedation
    Unarousable sedation


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    Next Steps
    Creator Insights


    • Patients with a RASS of -3 or less should have their sedation decreased or modified in order to achieve a RASS of -2 to 0.
    • Patients with a RASS of 2 to 4 are not sedated enough and should be assessed for pain, anxiety, or delirium. The underlying etiology of the agitation should be investigated and appropriately treated to achieve a RASS of -2 to 0.

    Critical Actions

    • A RASS score should be obtained on all hospitalized patients and at regular interval in all mechanically ventilated patients.
    • Unless a patient meets indication for deep sedation, a protocol for minimal sedation (RASS -2 to 0) should be used.


    Select responsiveness level of patient.

    Facts & Figures


    Criteria Definition Points
    Combative Overtly combative, violent, immediate danger to staff +4
    Very agitated Pulls or removes tube(s) or catheter(s); aggressive +3
    Agitated Frequent non-purposeful movement, fights ventilator +2
    Restless Anxious but movements not aggressive vigorous +1
    Alert and calm 0
    Drowsy Not fully alert, but has sustained awakening (eye-opening/eye contact) to voice (>10 seconds) -1
    Light sedation Briefly awakens with eye contact to voice (<10 seconds) -2
    Moderate sedation Movement or eye opening to voice (but no eye contact) -3
    Deep sedation No response to voice, but movement or eye opening to physical stimulation -4
    Unarousable No response to voice or physical stimulation -5

    Evidence Appraisal

    • The inter-rater reliability of RASS was demonstrated in a single-center ICU population in 2 phases; before and after implementation of RASS. In the second phase of the study, the scale was shown to have good inter-rater reliability (k=0.80) among trained nurses.
    • This single-center study prospectively assessed the inter-rater reliability of RASS in a medical ICU population. An excellent inter-rater reliability (k=0.91) was again demonstrated among nurses.
    Dr. Curtis Sessler

    About the Creator

    Curtis Sessler, MD, is a professor at Virginia Commonwealth University (VCU) Health System. He is also director of the Center for Adult Critical Care and medical director of Critical Care and the Medical Respiratory ICU at the Medical College of Virginia (MCV). Dr Sessler’s research interests focus on ICU sedation, prevention of nosocomial infection, mechanical ventilation, and procedural competency.

    To view Dr. Curtis Sessler's publications, visit PubMed

    Content Contributors
    About the Creator
    Dr. Curtis Sessler
    Content Contributors