TABLE 2.

Preoperative physical status classification according to the American Society of Anaesthesiology.

Class	Definition
1	A normal healthy patient.
2	A patient with mild systemic disease and no functional limitations.
3	A patient with moderate to severe systemic disease that results in functional limitation.
4	A patient with severe systemic disease that is a constant threat to life and functionally incapacitating.
5	A moribund patient who is not expected to survive 24 h with or without surgery.
6	A brain-dead patient whose organs are being harvested.

Source: Allman KG, Wilson LH. Pre-operative assessment and preparation for anaesthesia. Oxford textbook of anaesthesia. New York: Oxford University Press; 2011