Feature	Acute physiology score (APS)
Variable	+ 4	+ 3	+ 2	+ 1	0	+ 1	+ 2	+ 3	+ 4
Temperature	≥41	30 to 40.9		38.5 to 38.9	36 to 38.4	34 to 35.9	32 to 33.9	30 to 31.9	≤29.9
Mean arterial BP	≥160	130 to 159	110 to 129		70 to 109		50 to 69		< 49
Heart rate	≥180	140 to 179	110 to 139		70 to 109		55 to 69	40 to 54	≤39
Respiratory rate	≥50	35 to 49		25 to 34	12 to 24	10 to 11	6 to 9		< 5
A-aPo2*	≥500	350 to 499	200 to 349		< 1 00	61 to 70		55 to 60	< 55
Pao2†					> 70
Arterial pH	≥7.7	7.6 to 7.69		7.5 to 7.59	7.33 to 7.49		7.25 to 7.32	7.15 to 7.24	< 7.15
Serum bicarbonate‡	≥52	41 to 51.9		32 to 40.9	23 to 31.9		18 to 21.9	15 to 17.9	< 15
Serum sodium	≥180	160 to 179	155 to 159	150 to 154	130 to 149		120 to 129	111 to 119	≤ 110
Serum potassium	≥7	6 to 6.9		5.5 to 5.9	3.5 to 5.4	3 to 3.4	2.5 to 2.9		< 2.5
Serum creatinine	≥3.5	2 to 3.4	1.5 to 1.9		0.6 to 1.4		< 0.6
Hematocrit	≥60		50 to 59.9	46 to 49.9	30 to 45.9		20 to 29.9		< 20
WBC count	≥40		20 to 39.9	15 to 19.9	3 to 14.9		1 to 2.9		< 1