Neonatal Pain

Prematurity does not protect an infant from pain. Term and preterm newborns have functioning pathways for detecting noxious stimuli, yet their behavioural responses are immature and can be blunted by prematurity, critical illness, fatigue, mechanical ventilation, or medications. A still infant may be overwhelmed or physiologically unstable rather than comfortable. Acute pain can produce sympathetic activation: heart rate, respiratory rate, and blood pressure may rise, while oxygen saturation may fall. The infant may also tighten the face, furrow the brow, squeeze the eyes, cry, withdraw the limbs, stiffen, or become difficult to console. These findings are clues, not a diagnosis. The same changes can occur with hypoxaemia, sepsis, hypoglycaemia, hypothermia, or withdrawal. An experienced nurse first compares the infant with their own baseline and asks what happened immediately before the change. A brief facial response during a heel lance has a different meaning from persistent desaturation and poor perfusion in an infant who has not been handled. Timing helps, but it never replaces an airway, breathing, circulation, and underlying-cause assessment.