Heel-lancing in newborns: behavioral and spectral analysis assessment of pain control methods

Pain experience can alter clinical outcome, brain development, and subsequent behavior in newborns, primarily in preterm infants. The aims of this study were (1) to evaluate several simple, commonly used methods for pain control in newborns and (2) to evaluate the concordance between behavioral and autonomic cardiac reactivity to pain in term neonates during heel-lancing.

A prospective study was conducted of 180 term newborn infants who were undergoing heel-lancing for routine neonatal screening of phenylketonuria and hypothyroidism. Newborns were assigned to 6 groups: (1) control (no pain relief intervention); (2) nonnutritive sucking; (3) holding by mother; (4) oral glucose solution; (5) oral formula feeding; or (6) breastfeeding. Outcome measures included the Neonatal Facial Coding System score; cry duration; and autonomic variables obtained from spectral analysis of heart rate variability before, during, and after heel-lancing.

Infants with no pain control showed the highest pain manifestation compared with newborns to whom pain control was provided. Infants who breastfed or received an oral formula showed the lowest increase in heart rate (21 and 23 beats per minute, respectively, vs 36; P < .01), lowest neonatal facial score (2.3 and 2.9, respectively, vs 7.1; P < .001), lowest cry duration (5 and 13 seconds, respectively, vs 49; P < .001), and lowest decrease in parasympathetic tone (-2 and -2.4, respectively, vs 1.2; P < .02) compared with the other groups.

Any method of pain control is better than none. Feeding and breastfeeding during heel-lancing were found to be the most effective methods of pain relief.