Table 2

American College of Surgeons Advanced Trauma Life Support classification of haemorrhage severity

Haemorrhage severity according to ACS/ATLS classificationa
Class I
Class II
Class III
Class IV

Blood loss (ml)
<750
750–1,500
1,500–2,000
>2,000
Pulse rate (per minute)
<100
>100
>120
>140
Blood pressure
Normal
Normal
Decreased
Decreased
Pulse pressure (mm Hg)
Normal
Decreased
Decreased
Decreased
Respiratory rate (per minute)
14–20
20–30
30–40
>40
Urine output (ml/hour)
>30
20–30
5–15
Negligible
Central nervous system (mental status)
Slightly anxious
Mildly anxious
Anxious, confused
Lethargic

aValues are estimated for a 70-kg adult. Table reprinted with permission from the American College of Surgeons [26]. ACS/ATLS, American College of Surgeons/Advanced Trauma Life Support.

Spahn et al. Critical Care 2007 11:R17   doi:10.1186/cc5686