Table 1.

ASA score and associated mortality (after [4] with permission from the ASA).

ASA class	Description	Examples	Mortality (%)
1	A normal healthy patient	Healthy, non-smoking, no or minimal alcohol use	0.1
2	A patient with mild systemic disease	Mild diseases only without substantive functional limitations Examples include (but are not limited to): current smoker, social alcohol drinker, pregnancy, obesity (30<BMI<40), well-controlled diabetes or hypertension, mild lung disease	0.7
3	A patient with severe systemic disease	Substantive functional limitations; one or more moderate-to-severe diseases Examples include: poorly controlled diabetes or hypertension, lung disease, BMI ≥40, alcohol dependence or abuse, implanted pacemaker, end-stage renal disease undergoing regular dialysis, history (>3 months) of MI, CVA, TIA, or CAD/stents	3.5
4	A patient with severe systemic disease that is a constant threat to life	Examples include: recent (<3 months) MI, CVA, TIA, or CAD/stents, ongoing cardiac ischaemia or severe valve dysfunction, severe reduction of ejection fraction, end-stage renal disease not undergoing regular dialysis	18.3
5	Moribund patient unlikely to survive without the operation	Examples include (but are not limited to): ruptured abdominal/thoracic aneurysm, massive trauma, intracranial bleed with mass effect, ischaemic bowel in the face of significant cardiac pathology or multiple organ/system dysfunction	93.3
6	A declared brain-dead patient whose organs are being removed for donor purposes

CAD, coronary arterial disease; CVA, cerebrovascular accident; MI, myocardial infarction; TIA, transient ischaemic attack.