Classification of hypovolaemia in children
	Class I	Class II	Class III	Class IV
Blood volume lost	<15%	15–25%	25–40%	>40%
Pulse rate	Increased	>150	>150	Increased or bradycardia
Pulse pressure	Normal	Reduced	Very reduced	Absent
Systolic blood	Normal	Reduced	Very reduced	Unrecordable pressure
Capillary refill time	Normal	Prolonged	Very prolonged	Absent
Respiratory rate	Normal	Increased	Increased	Slow sighing respiration
Mental state	Normal	Irritable	Lethargic	Comatosed
Urine output	<1 ml/kg/hr	<1 ml/kg/hr	<1ml/kg/hr	<1 ml/kg/hr