Modified Aldrete score
Readiness for discharge from the post-anaesthesia care unit (PACU)
Sources last checked: 2026-10-13
Modified Aldrete score
Readiness for discharge from the post-anaesthesia care unit (PACU)
The score does not assess pain, nausea, bleeding or the surgical site. Discharge thresholds are set locally; day-surgery discharge home needs additional criteria.
Interpretation
| < 9 — below discharge threshold | Below the commonly used threshold for transfer from the PACU. |
|---|---|
| ≥ 9 — discharge criterion met | Commonly used threshold for transfer from the PACU, provided local criteria (pain, nausea, bleeding) are also met. |
What is the Modified Aldrete score?
The modified Aldrete score rates five domains — activity, respiration, circulation, consciousness and oxygen saturation — from 0 to 2 each to judge recovery after anaesthesia. Aldrete introduced the original score in 1970 and replaced the colour item with pulse oximetry in 1995. A total of 9 or more is widely used as a criterion for leaving the post-anaesthesia care unit.
When to use it
- Structured assessment in the PACU / recovery room
- Documenting readiness for transfer to the ward or a phase-II recovery area
- Teaching recovery-room assessment in a systematic way
When not to use it
- As the only criterion for discharge home after day surgery (pain, nausea, bleeding, voiding and escort need separate checks)
- Patients with chronic baseline deficits (e.g. hemiplegia, home oxygen) without adjusting interpretation
How it is calculated
| Criterion | Points |
|---|---|
| Activity | |
| Moves 4 extremities voluntarily or on command | 2 |
| Moves 2 extremities | 1 |
| Moves no extremity | 0 |
| Respiration | |
| Breathes deeply and coughs freely | 2 |
| Dyspnoea or limited breathing | 1 |
| Apnoeic | 0 |
| Circulation (blood pressure vs pre-anaesthetic level) | |
| Within ± 20 % | 2 |
| ± 20–49 % | 1 |
| ± 50 % or more | 0 |
| Consciousness | |
| Fully awake | 2 |
| Arousable on calling | 1 |
| Not responding | 0 |
| Oxygen saturation | |
| SpO₂ > 92 % on room air | 2 |
| Needs O₂ to keep SpO₂ > 90 % | 1 |
| SpO₂ < 90 % even with O₂ | 0 |
Clinical pearls and limitations
- The score does not assess pain, nausea, bleeding or the surgical site. Discharge thresholds are set locally; day-surgery discharge home needs additional criteria.
- Circulation is judged relative to the patient's own pre-anaesthetic blood pressure, not to absolute values.
- Patients after regional anaesthesia may score low on activity despite full recovery from sedation; document the block.
- Discharge thresholds are institutional; many units also require pain and PONV control.
Frequently asked questions
What Aldrete score is needed for PACU discharge?
A total of 9 or more is the commonly used threshold, alongside local criteria such as pain and nausea control.
What changed in the modified Aldrete score?
In 1995 Aldrete replaced the colour (skin appearance) item with pulse oximetry.
What is the maximum Aldrete score?
10 — two points for each of the five domains.
Evidence and guidelines
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