Richmond Agitation-Sedation Scale (RASS)

Why Use

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.

When to 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.

Formula

Pearls / Pitfalls

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.

Management

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.

More Information

Definitions: 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