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APACHE II Score
Acute Physiology and Chronic Health Evaluation II — ICU mortality prediction
Acute Physiology Score (worst values in first 24h of ICU)
Oxygenation
Age & Chronic Health
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APACHE II Score
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APS
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Age Points
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Chronic Health
Estimated ICU Mortality:
APACHE II Mortality Reference
| Score | Est. Mortality | Score | Est. Mortality |
|---|---|---|---|
| 0–4 | 4% | 20–24 | 40% |
| 5–9 | 8% | 25–29 | 55% |
| 10–14 | 15% | 30–34 | 73% |
| 15–19 | 25% | ≥35 | 85% |
APACHE II = APS + Age Points + Chronic Health Points (max 71)
APS = sum of 12 physiological variables (GCS component = 15 − GCS)
Mortality validated in medical-surgical ICU; less accurate for specific diagnoses
APS = sum of 12 physiological variables (GCS component = 15 − GCS)
Mortality validated in medical-surgical ICU; less accurate for specific diagnoses
Limitations: APACHE II was developed in 1985 and validated on data from before modern ICU practices. It tends to overestimate mortality in some centres. APACHE IV, SAPS III, and SOFA may be more appropriate in modern ICUs.
For clinical decision support only. Not a substitute for professional medical judgment.
