SAPS II Calculator
Simplified Acute Physiology Score II for ICU mortality risk assessment
SAPS II Assessment
Vitals
Oxygenation
Renal Function
Chemistry
Other Parameters
SAPS II Formula
X = -7.7631 + 0.0737 × SAPS II + 0.9971 × ln(SAPS II + 1)
Mortality = e^X / (1 + e^X)
Where X is the logit transformation and ln is the natural logarithm.
Risk Reference
Understanding SAPS II
What is SAPS II?
The Simplified Acute Physiology Score II (SAPS II) is a severity scoring system used to predict ICU mortality risk. It evaluates 15 parameters including physiological measurements, patient characteristics, and admission type to calculate a comprehensive risk assessment for patients aged 15 years and older.
Clinical Applications
- •ICU quality assessment and benchmarking
- •Research and clinical trial stratification
- •Resource allocation and planning
- •Risk adjustment for mortality comparisons
SAPS II Components
Physiological Variables (12)
Vital signs, neurological status, oxygenation, renal function, and key laboratory values representing acute physiological derangement.
Age
Patient age as a primary predictor of ICU mortality, with increasing points for older patients.
Disease-Related Variables (2)
Chronic conditions (AIDS, malignancy) and type of admission (scheduled vs emergency surgery vs medical).
Scoring Guidelines
Data Collection
- • Use worst values from first 24 hours in ICU
- • For readmissions, calculate new SAPS II score
- • If mechanical ventilation, use P/F ratio
- • For multiple chronic diseases, use highest points
Limitations
- • Not validated for burn or cardiac surgery patients
- • Population-based prediction, not individual
- • May need local calibration
- • Should not guide treatment withdrawal decisions
Clinical Note: SAPS II is intended for quality assessment and research purposes. While it provides valuable prognostic information, it should never be used as the sole basis for clinical decision-making or treatment limitation discussions with patients and families.