APACHE scoring

• The APACHE (Acute physiology and chronic health evaluation) score utilises a point score derived from the degree of abnormality of readily obtainable physiological and laboratory variables in the first 24h of ICU admission, plus extra points for age and chronic ill health.

• The summated score provides a measure of severity while the percentage risk of subsequent death can be computed from specific coefficients applied to a wide range of admission disorders (excluding burns and cardiac surgery).

• APACHE I, fi rst described in 1981, utilised 34 physiological and biochemical variables.

• A simplified version (APACHE II) utilising just 12 variables was published in 1985 and extensively validated in different countries.

A further refinement published in 1990, APACHE III, claims to improve upon the statistical predictive power by adding five new physiological variables (albumin, bilirubin, glucose, urea, urine output), changing thresholds and weighting of existing variables, comparing both admission and 24h scores, incorporating the admission source (e.g. ward, operating theatre), and reassessing effects of age, chronic health, and specific disease category. Wide acceptance of APACHE III may be limited as its risk stratification

system is proprietary and has to be purchased.

Acute physiology score

Age points

Years	≤44	45–54	55–64	65–74	≥75
Points	0	2	3	5	6

Chronic health points

Two points for elective post-operative admission or five points if emergency

operation or non-operative admission, if patient has either:

• Biopsy-proven cirrhosis, portal hypertension, or previous hepatic failure.

• Chronic heart failure (NYHA Grade 4).

• Chronic hypoxia, hypercapnia, severe exercise limitation, 2* polycythaemia, or pulmonary hypertension.

• Dialysis-dependent renal disease.

• Immunosuppression by disease or drugs.