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Inputs used

Breakdown

Calculation steps

Returned data table

Input contract

• Worst core temperature — °C; minimum 20; maximum 45
• Worst mean arterial pressure — mmHg; minimum 0; maximum 250
• Worst heart rate — beats/min; minimum 0; maximum 300
• Worst respiratory rate — breaths/min; minimum 0; maximum 100
• Oxygenation variable — 2 choices
• PaO₂ or A–aDO₂ value — mmHg; minimum 0; maximum 1000
• Arterial pH — pH; minimum 6; maximum 9
• Serum sodium — mmol/L; minimum 50; maximum 250
• Serum potassium — mmol/L; minimum 1; maximum 10
• Serum creatinine — mg/dL; minimum 0; maximum 20
• Acute renal failure doubling rule — 2 choices
• Hematocrit — %; minimum 0; maximum 80
• White-cell count — ×10³/µL; minimum 0; maximum 100
• Glasgow Coma Scale — points; minimum 3; maximum 15
• Age — years; minimum 0; maximum 120
• Qualifying chronic-health status — 3 choices

Worked example

All entered values are in the zero-point bands, so APACHE II = 0 + 0 + 0 = 0 points.

Assumptions and limits

• Inputs represent the worst qualifying values in the specified assessment window, entered by trained clinical staff.
• Temperature is core temperature in degrees Celsius and blood pressure is entered as mean arterial pressure, not systolic pressure.
• The oxygenation mode is selected according to FiO₂ and the corresponding PaO₂ or A–aDO₂ value is entered in mmHg.
• Creatinine is entered in mg/dL and its APACHE point is doubled only when the acute renal failure rule is explicitly selected.
• GCS points are calculated as 15 minus the actual GCS, with GCS constrained to 3–15.
• Age and chronic-health points are added to the acute physiology score exactly as selected, with no mortality equation applied.
• The score is intended for trained ICU severity assessment and population-level comparison, not individual triage or treatment selection.
• Local protocols, source documentation, and qualified critical-care judgment take priority if they use a different version or handling rule.

Calculator note