Aldrete Score Calculator
The Modified Aldrete Score is a five-parameter clinical assessment used in post-anesthesia care units (PACUs) to determine when a patient is ready to be safely discharged after surgery under general, regional, or local anesthesia. Rate each of the five criteria on a 0-2 scale. A total score of 9 or 10 generally indicates the patient can leave the PACU. Results update instantly as you change any value.
What is the Aldrete Score?
The Aldrete Score (also called the Post Anesthesia Recovery Score) is a structured clinical tool developed in 1970 by anesthesiologist Jorge Antonio Aldrete while working at the Denver Veterans Affairs Hospital. It provides a standardized, objective method for evaluating patient recovery from anesthesia before transfer out of the post-anesthesia care unit (PACU). The score evaluates five physiological parameters - activity, respiration, circulation, consciousness, and either skin colour (original) or oxygen saturation (modified) - each rated from 0 to 2, for a maximum of 10 points. The 1995 modified version replaced the subjective skin-colour criterion with pulse oximetry, making the assessment more objective and consistent with modern monitoring practice.
How to use this calculator
Select either the Modified 1995 version (recommended, uses SpO2) or the Original 1970 version (uses skin colour). Then rate each of the five parameters using the dropdown menus based on your clinical assessment of the patient. The score updates instantly. A total of 9 or 10 meets the standard discharge threshold for most PACU settings. Scores of 8 or below indicate that the patient requires continued observation. The Aldrete Score is a screening tool - it does not replace clinical judgment, and supplementary assessments for pain, nausea, bleeding, and ambulation ability are always required before discharging a patient.
The five Aldrete Score parameters explained
Activity measures how many limbs the patient can move on command - 0 if none, 1 if two, 2 if all four. This reflects neurological and neuromuscular recovery. Respiration assesses breathing quality: 2 for deep breathing and the ability to cough, 1 for dyspnea or shallow breathing, 0 for apnea or ventilator dependence. Circulation compares current blood pressure to the documented pre-operative baseline: within 20% scores 2, a 21-49% deviation scores 1, and 50% or more deviation scores 0. Consciousness is rated 2 if the patient is fully awake, 1 if they respond to verbal stimuli but are drowsy, and 0 if unresponsive. In the modified version, the colour criterion is replaced by SpO2: 2 if the patient maintains more than 92% saturation on room air, 1 if supplemental oxygen is needed to stay above 90%, and 0 if saturation falls below 90% despite supplemental oxygen.
Discharge thresholds and limitations
Most institutions require a minimum Aldrete Score of 9 before a patient can leave the PACU for a ward or be discharged home after ambulatory surgery. Some facilities use a threshold of 8 with clinical discretion, but a score of 7 or below universally requires continued PACU care and repeated assessment. Importantly, the Aldrete Score does not evaluate pain intensity, postoperative nausea and vomiting (PONV), temperature, wound status, urine output, or the patient's ability to safely walk. These must be assessed independently. For ambulatory surgical patients, additional Phase II recovery criteria (such as the PADSS or White-Song criteria) are often applied before home discharge.
Aldrete Score - Criteria and Interpretation
| Parameter | Score 2 | Score 1 | Score 0 |
|---|---|---|---|
| Activity | Moves all 4 extremities | Moves 2 extremities | Cannot move any extremity |
| Respiration | Deep breath, coughs freely | Dyspnea or limited breathing | Apneic |
| Circulation | BP within 20% of baseline | BP 21-49% from baseline | BP 50%+ from baseline |
| Consciousness | Fully awake | Arousable on calling | Not responding |
| Colour / SpO2 (modified) | SpO2 >92% on room air | Needs O2, SpO2 >90% | SpO2 <90% despite O2 |
Each of the five parameters is scored 0, 1, or 2. Maximum total is 10. A score of 9-10 is generally required for safe PACU discharge.
Frequently asked questions
What Aldrete Score is needed before leaving the PACU?
The standard threshold is 9 or 10 out of 10. Most post-anesthesia care units require at least 9 points before safely transferring a patient to a ward or discharging an outpatient. A score of 8 is borderline and requires close clinical assessment; scores of 7 or below mandate continued PACU monitoring and targeted interventions.
What is the difference between the original and modified Aldrete Score?
The original 1970 Aldrete Score assessed skin colour subjectively - normal, pale or blotchy, or cyanotic. In 1995, Aldrete revised the scoring to replace this with pulse oximetry (SpO2), making the assessment more objective. A SpO2 above 92% on room air scores 2, a reading above 90% with supplemental oxygen scores 1, and below 90% despite oxygen scores 0. The modified version is now standard in most modern PACUs.
What does the Aldrete Score not assess?
The Aldrete Score does not measure pain, postoperative nausea and vomiting, body temperature, surgical-site condition, urine output, or ambulation ability. These factors are clinically important for safe discharge and must be evaluated separately using supplementary tools or clinical protocols before a final discharge decision is made.
Can the Aldrete Score be used for children?
The Aldrete Score was originally developed for adult patients. While its parameters are physiologically valid in children, pediatric-specific recovery scores such as the Steward Coma Scale are often preferred in pediatric anesthesia settings because they are adapted for age-related differences in consciousness, breathing effort, and motor response.
How often should the Aldrete Score be reassessed?
In most PACU protocols, the Aldrete Score is assessed on arrival and then every 15 to 30 minutes until discharge criteria are met. Patients who score below 9 on repeated assessments should have the specific low-scoring parameters addressed - for example, administering supplemental oxygen for low SpO2, managing blood pressure, or allowing more time for residual anesthetic to clear before re-scoring.