Prematurity alters skin conductance and behavioural scoring after acute stress in term-equivalent age infants.

Abstract

The primary objective was to assess the effect of prematurity at term-equivalent age on skin conductance and behavioural responses to acute stress. The secondary objective was to explore the reliability of skin conductance in detecting neonatal discomfort in preterm and full-term populations. Very preterm infants at term-equivalent age and healthy full-term neonates, 34 infants in each group, underwent the hip dysplasia screening test. The acute pain in newborn infants (APN) scale was scored before and 15, 45 and 90seconds after stimulus. Skin conductance was measured in the 30-second time-lap before and after stimulus. The APN score was lower in preterm infants after intervention (term: 5.4±2.8 vs. preterm: 3.9±2.2; p=0.03). Peaks-per-second, a skin conductance parameter, exhibited lower basal values in preterm infants than in term infants, with similar rise induced by stressful challenge. Peaks-per-second values were correlated to the 15-second APN score in both groups (term: r=0.55, p<0.001; preterm: r=0.43, p=0.01). Preterm birth changed skin conductance signal and behavioural response to stress at term-equivalent age. The skin conductance device may be an objective tool for a continuous monitoring of acute neonatal stress.