Acute Physiologic Assessment and Chronic Health Evaluation (APACHE) II Scoring System*
Physiologic Variable† | Point Score | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
+4 | +3 | +2 | +1 | 0 | +1 | +2 | +3 | +4 | ||
1 | Temperature, core (°C) | ≥ 41° | 39–40.9° | — | 38.5–38.9° | 36–38.4° | 34–35.9° | 32–33.9° | 30–31.9° | ≤ 29.9° |
2 | Mean arterial pressure (mm Hg) | ≥ 160 | 130–159 | 110–129 | — | 70–109 | — | 50–69 | — | ≤ 49 |
3 | Heart rate | ≥ 180 | 140–179 | 110–139 | — | 70–109 | — | 55–69 | 40–54 | ≤ 39 |
4 | Respiratory rate (nonventilated or ventilated) | ≥ 50 | 35–49 | — | 25–34 | 12–24 | 10–11 | 6–9 | — | ≤ 5 |
5 | Oxygenation: a) FIO2 ≥ 0.5: use A-aDO2 | ≥ 500 | 350–499 | 200–349 | — | < 200 | — | — | — | — |
b) FIO2 < 0.5: use PAO2 (mm Hg) | — | — | — | — | > 70 | 61–70 | — | 55–60 | < 55 | |
6 | Arterial pH | ≥ 7.7 | 7.6–7.69 | — | 7.5–7.59 | 7.33–7.49 | — | 7.25–7.32 | 7.15–7.24 | < 7.15 |
7 | Serum sodium (mmol/L or mEq/L) | ≥ 180 | 160–179 | 155–159 | 150–154 | 130–149 | — | 120–129 | 111–119 | ≤ 110 |
8 | Serum potassium (mmol/L or mEq/L) | ≥ 7 | 6–6.9 | — | 5.5–5.9 | 3.5–5.4 | 3–3.4 | 2.5–2.9 | — | < 2.5 |
9 | Serum creatinine (micromol/L or mg/dL); double point score for patients with acute renal failure | ≥ 3.5 | 2–3.4 | 1.5–1.9 | — | 0.6–1.4 | — | < 0.6 | — | — |
10 | Hematocrit (%) | ≥ 60 | — | 50–59.9 | 46–49.9 | 30–45.9 | — | 20–29.9 | — | < 20 |
11 | White blood cells (in 1000s) | ≥ 40 | — | 20–39.9 | 15–19.9 | 3–14.9 | — | 1–2.9 | — | < 1 |
12 | Glasgow coma score (GCS) | Score = 15 minus actual GCS (see table Glasgow Coma Scale) | ||||||||
Acute physiology score is the sum of the 12 individual variable points. | ||||||||||
Add 0 points for age < 44 years; 2 points, 45–54 years; 3 points, 55–64 years; 5 points, 65–74 years; 6 points ≥ 75 years. | ||||||||||
Add chronic health status points: 2 points for elective postoperative patient with immunocompromise or history of severe organ insufficiency; 5 points for nonoperative patient or emergency postoperative patient with immunocompromise or severe organ insufficiency.‡ | ||||||||||
(13)§ | Serum bicarbonate (venous–mmol/L or mEq/L) | ≥ 52 | 41–51.9 | — | 32–40.9 | 23–31.9 | — | 18–21.9 | 15–17.9 | < 15 |
* APACHE II score = acute physiology score + age points + chronic health points. Minimum score = 0; maximum score = 71. Increasing score is associated with increasing risk of hospital death. | ||||||||||
† Choose worst value in the past 24 hours. | ||||||||||
‡ Chronic health status: Organ insufficiency (eg, hepatic, cardiovascular, renal, pulmonary) or immunocompromised state must have preceded current admission. | ||||||||||
§ This variable is optional; use only if no arterial blood gases are available. | ||||||||||
A-a DO2 = alveolar–arterial oxygen gradient; FIO2 = fractional inspired oxygen. | ||||||||||
Adapted from Knaus WA, Draper EA, Wagner DP, Zimmerman JE: APACHE II: A severity of disease classification system. Critical Care Medicine 13:818–829, 1985. | ||||||||||