Chart — Critical Care
Sedation Scale Comparison Chart
A side-by-side comparison of the two most commonly used ICU sedation scales — RASS and SAS — including scale ranges, score interpretation, target ranges, and typical clinical use.
Educational use only. Sedation target ranges are individualized by the care team. Always follow provider orders and institutional protocols for sedation assessment and titration. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
RASS vs SAS — Overview Comparison
| Feature | RASS | SAS |
|---|---|---|
| Full Name | Richmond Agitation-Sedation Scale | Sedation-Agitation Scale |
| Scale Range | −5 to +4 (10 levels) | 1 to 7 (7 levels) |
| Agitation Direction | Positive numbers (+1 to +4) | Higher numbers (5–7) |
| Deep Sedation | Negative numbers (−3 to −5) | Lower numbers (1–2) |
| Typical Target Range | 0 to −2 (calm to light sedation) | 3–4 (sedated to calm/cooperative) |
| SAT Threshold | RASS ≥ −3 (responds to voice) | SAS ≥ 3 (responds to stimulation) |
| Delirium Screening | RASS ≥ −3 required for CAM-ICU | SAS ≥ 3 required for delirium screening |
| Validation | Widely validated; preferred by PADIS guidelines | Well-validated; original ICU agitation scale |
RASS Score Quick Reference
| Score | Label | ICU Interpretation |
|---|---|---|
| +4 / +3 | Combative / Very Agitated | Danger to staff; pulling at tubes — immediate intervention needed |
| +2 / +1 | Agitated / Restless | Anxious, fighting ventilator — assess for pain, delirium, hypoxia |
| 0 | Alert and Calm | Ideal for cooperative, non-ventilated patients or during SAT |
| −1 / −2 | Drowsy / Light Sedation | Typical target for mechanically ventilated patients |
| −3 / −4 | Moderate / Deep Sedation | Appropriate for ARDS, ICP management, or acute procedures — assess daily |
| −5 | Unarousable | Rarely appropriate without specific indication — review sedation orders |
SAS Score Quick Reference
| Score | Label | ICU Interpretation |
|---|---|---|
| 7 / 6 | Dangerous / Very Agitated | Pulling at ETT, climbing out of bed — immediate intervention needed |
| 5 | Agitated | Anxious but calms with verbal redirecting |
| 4 | Calm and Cooperative | Ideal awake state — follows commands, arousable |
| 3 | Sedated | Typical target for mechanically ventilated patients |
| 2 / 1 | Very Sedated / Unarousable | Deep sedation — assess necessity; daily SAT evaluation recommended |
Nursing Application Notes
- Consistent scale use: Use whichever scale is standard at your institution. Consistency within a unit matters more than which scale is chosen.
- Scale direction note: RASS uses negative numbers for sedation (lower = deeper); SAS uses lower positive numbers for sedation. This is a common source of confusion — know your unit's scale direction.
- Document and report changes: A change of 2 or more score points in either direction warrants clinical assessment and communication to the provider.
- Integration with delirium screening: CAM-ICU delirium assessment requires RASS ≥ −3 or SAS ≥ 3 — too deeply sedated patients cannot be accurately screened.
- ABCDEF Bundle: In the ABCDEF ICU liberation bundle, sedation/agitation assessment supports element B — Both spontaneous awakening trials (SATs) and spontaneous breathing trials (SBTs) — while element A is Assess, prevent, and manage pain.
Related Resources
Standards & sources
Fact-checked Jun 20, 2026This page is written to align with PADIS Guidelines / SCCM. It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →