APACHE II Score Assessment Tool
Overview: This specialized calculator estimates intensive care unit (ICU) mortality risk for patients by analyzing medical history, physical examination findings, and laboratory results within the first 24 hours of admission. Developed in 1981, the APACHE II score is a globally recognized critical care system that helps clinicians assess disease severity, guide treatment, and compare patient outcomes.
Disclaimer: This tool is for informational and educational purposes only. It is not a substitute for professional medical diagnosis, advice, or treatment. Always consult a qualified physician for any health concerns.
Understanding the APACHE II Scoring System
The Acute Physiology and Chronic Health Evaluation II (APACHE II) is a foundational critical care scoring system developed in the 1980s. Healthcare providers globally utilize this tool to gauge disease severity and predict mortality risk for ICU patients during their initial 24 hours of admission. By offering a standardized assessment, it aids clinicians in tailoring treatment strategies and comparing patient outcomes.
How to Operate the APACHE II Calculator
This section outlines the steps to accurately compute an APACHE II score. The calculator requires input across three primary sections: Patient Characteristics, Physical Examination Findings, and Laboratory Test Results. It is essential to complete all fields to generate a valid result.
Detailed Input Parameters
- Age: This scoring system is applicable to patients aged 16 years and older.
- History of Severe Organ Insufficiency: Indicate if present. For surgical patients, specify whether the procedure was elective or an emergency.
- Chronic conditions considered include:
- NYHA Class IV heart failure.
- Chronic dialysis dependence.
- Liver cirrhosis with complications like portal hypertension.
- Immunocompromised status.
- Renal Failure: Assess kidney function. Clinical judgment is required to classify it as acute or chronic.
- Temperature: Input values in Celsius or Fahrenheit.
- Glasgow Coma Scale (GCS): Enter a score between 3 and 15.
- Mean Arterial Pressure (MAP): This can be calculated using the formula:
MAP = (1/3 * Systolic BP) + (2/3 * Diastolic BP). - Heart Rate: Record in beats per minute.
- Respiratory Rate: Count breaths over one minute.
- Oxygenation (FiO₂):
- If FiO₂ is 50% or higher, use the Alveolar-arterial (A-a) gradient.
- If FiO₂ is below 50%, use the PaO₂ value.
- Hematocrit: The percentage of red blood cells in blood.
- White Blood Cell Count: Provided in thousands per cubic milliliter.
- Arterial Blood pH: A measure of blood acidity/alkalinity.
- Serum Potassium & Sodium Levels: Can be entered in mmol/L or mEq/L.
- Serum Creatinine: A key marker for kidney function.
APACHE II Score Calculation Breakdown
The final APACHE II score (range 0 to 71) is the sum of points assigned across all categories. The total score correlates with an estimated mortality risk percentage.
Patient Characteristics Points
- Age Points: ≤44 (0), 45-54 (2), 55-64 (3), 65-74 (5), >74 (6).
- Organ Insufficiency/Immunocompromised: Yes, non-operative/emergency post-op (5); Yes, elective post-op (2); No (0).
Physical Examination Points
- Temperature (°C): ≥41 (4), 39-40.9 (3), 38.5-38.9 (1), 36-38.4 (0), 34-35.9 (1), 32-33.9 (2), 30-31.9 (3), <30 (4).
- Glasgow Coma Scale: Points are
15 - GCS score. - Mean Arterial Pressure (mmHg): >159 (4), 130-159 (3), 110-129 (2), 70-109 (0), 50-69 (2), ≤49 (4).
- Heart Rate (bpm): ≥180 (4), 140-179 (3), 110-139 (2), 70-109 (0), 55-69 (2), 40-54 (3), <40 (4).
- Respiratory Rate (bpm): ≥50 (4), 35-49 (3), 25-34 (1), 12-24 (0), 10-11 (1), 6-9 (2), <6 (4).
- Oxygenation:
- For FiO₂ ≥50% (A-a gradient): >499 (4), 350-499 (3), 200-349 (2), <200 (0).
- For FiO₂ <50% (PaO₂): >70 (0), 61-70 (1), 55-60 (3), <55 (4).
Laboratory Test Points
- Hematocrit (%): ≥60 (4), 50-59 (2), 46-49 (1), 30-45 (0), 20-29 (2), <20 (4).
- WBC Count (per mm³): ≥40,000 (4), 20,000-39,999 (2), 15,000-19,999 (1), 3,000-14,999 (0), 1,000-2,999 (2), <1,000 (4).
- Arterial pH: ≥7.7 (4), 7.6-7.69 (3), 7.5-7.59 (1), 7.33-7.49 (0), 7.25-7.32 (2), 7.15-7.24 (3), <7.15 (4).
- Potassium (mmol/L): ≥7.0 (4), 6.0-6.9 (3), 5.5-5.9 (1), 3.5-5.4 (0), 3.0-3.4 (1), 2.5-2.9 (2), <2.5 (4).
- Sodium (mmol/L): ≥180 (4), 160-179 (3), 155-159 (2), 150-154 (1), 130-149 (0), 120-129 (2), 111-119 (3), <111 (4).
- Creatinine (mg/dL):
- Acute Renal Failure: ≥3.5 (8), 2.0-3.4 (6), 1.5-1.9 (4).
- Chronic Renal Failure: ≥3.5 (4), 2.0-3.4 (3), 1.5-1.9 (2).
- No Acute/Chronic Failure: 0.6-1.49 (0), <0.6 (2).