Table 1

Responses of infants to pain

Physiological changesBehavioural changesBiochemical changes
Increase in:Change in facial expression12:Increased release of:
    • Heart rate    • Grimacing    • Cortisol
    • Blood pressure    • Screwing up of eyes    • Catecholamines
    • Respiratory rate    • Nasal flaring    • Glucagon
    • Oxygen consumption    • Deep nasolabial groove    • Growth hormone
    • Mean airway pressure    • Curving of the tongue    • Renin
    • Muscle tone    • Quivering of the chin    • Aldosterone
    • Intracranial pressure    • Antidiuretic hormone
Body movements13:
Autonomic changes10,11:    • Finger clenchingDecreased secretion of:
    • Mydriasis    • Thrashing of limbs    • Insulin
    • Sweating    • Writhing
    • Flushing    • Arching of back
    • Pallor    • Head banging