Healthcare & Clinical Calculators
SAPS 3 (Simplified Acute Physiology Score 3) First-Hour ICU Mortality
Sum the three SAPS 3 ICU admission boxes (Box I Patient History, Box II Admission Circumstances, Box III First-Hour Acute Physiology) and evaluate Moreno et al.’s (2005) global mortality equation!
First-hour ICU benchmarking separating pre-ICU case mix (Boxes I–II) from acute physiology (Box III)!
Whereas SAPS II measured worst 24-hour ICU values (confounding baseline severity with early ICU care quality!), Rui P. Moreno, Philipp G. H. Metnitz, et al. (Intensive Care Medicine, 2005; n = 16,784 patients across 303 ICUs in 35 countries) redesigned SAPS 3 strictly within ±1 hour of ICU admission across three transparent boxes: Box I (Age, Comorbidities, Prior Length of Stay/Location, Vasoactive Therapy), Box II (Planned vs. Unplanned Admission, Surgical Status, Nosocomial/Respiratory Infection, Specific ICU Reason), and Box III (10 Acute Physiologic Derangements)!
Total SAPS 3 score S = Box_I + Box_II + Box_III transforms nonlinearly into global predicted in-hospital mortality via logit = -32.6659 + LN(S + 20.5958) * 7.3068 and P(%) = 100 / (1 + EXP(-logit))! Check an unplanned septic-shock surgical admission with Box I = 18, Box II = 22, and Box III = 26 (Total SAPS 3 = 66): global predicted hospital mortality reaches 48.29%, vs. 4.01% for an elective post-op admission [12, 10, 14] (SAPS 3 = 36)!
| SAPS 3 Three-Box Breakdown [Box I, II, III] | Total SAPS 3 Score | Global Logit | Predicted Hospital Mortality (%) |
|---|---|---|---|
| [12, 10, 14] — Elective Post-Op ICU | 36 pts | -3.1755 | 4.01% |
| [18, 22, 26] — Unplanned Septic Shock | 66 pts | -0.0684 | 48.29% |
| Negative Box Subscore (< 0) | Invalid | Undefined | "Invalid SAPS 3 Subscore" |
SAPS 3 Global Predicted In-Hospital Mortality (%)
Evaluates Moreno et al.’s (2005) global calibration equation 100 / (1 + EXP(-(-32.6659 + LN(SUM(B2:B4) + 20.5958) * 7.3068))) across Box I (B2), Box II (B3), and Box III (B4).
=IF(MIN(B2:B4) < 0, "Invalid SAPS 3 Subscore", ROUND(100 / (1 + EXP(-(-32.6659 + LN(SUM(B2:B4) + 20.5958) * 7.3068))), 2))Total SAPS 3 Admission Score (Box I + Box II + Box III)
Sums chronic/prior-location Box I, admission-reason Box II, and ±1h physiology Box III.
=IF(MIN(B2:B4) < 0, "Invalid SAPS 3 Subscore", SUM(B2:B4))Try the example
Use the original values or change them to test your understanding.