BACKGROUND: Healthy neonates routinely undergo painful minor procedures. Evidence suggests that infants do feel pain, and painful experiences may lead to subsequent increased pain sensitivity. Due to concerns regarding the potential adverse effects of pharmacological interventions in newborns, effective alternatives for pain control have been sought.
Previous studies have demonstrated analgesic benefit with the oral administration of sugar solutions, nonnutritive sucking, and skin-to-skin contact. Further studies have suggested that breastfeeding may have similar value in pain control, but no study has sought to directly compare these approaches.
POPULATION STUDIED: The researchers observed 180 term, breastfed infants ranging in age from 1 to 5 days. All infants included in the study were healthy, with 5-minute Apgar scores 7 out of 10. Infants who were unstable or who had received a sedative, major analgesic, or naloxone in the previous 24 to 48 hours were excluded from the study.
STUDY DESIGN AND VALIDITY: Infants and their mothers were taken to a quiet room for venipuncture. They were randomly assigned to 1 of 4 groups. In the first group, infants were breastfed for 2 minutes prior to and during venipuncture. In the second group, infants were held in their mothers’ arms without breast-feeding prior to and during the procedure. In the third group, infants were laid on a table and given 1 mL of sterile water orally through a syringe over the course of 15 seconds. In the fourth group, infants were laid on a table and given 30% sucrose solution orally followed by a pacifier.
The infants’ heart rate and oxygen saturation were monitored. All infants and their monitoring equipment were videotaped from the beginning to the end of venipuncture. Two independent, specially trained observers evaluated these tapes. The observers were blinded to the purpose and hypothesis of the study. There was a high degree of agreement between the 2 observers in the outcomes measured.
Overall, this study was well designed. Allocation of participants to treatment groups was effectively concealed. The observers were blinded to the purpose and hypothesis of the study. However, they clearly did observe a difference in the treatment groups. Pre-existing perceptions of the benefits of breastfeeding could have affected the observers ratings of the infants’ responses.
OUTCOMES MEASURED: The observers rated the infants’ expression of pain. The Douleur Aiguë Nouveau-né (DAN) scale evaluates facial expressions, limb movements, and vocalizations in infants to generate a score from 0 (no pain) to 10 (maximum pain). A second pain scale, the Premature Infant Pain Profile (PIPP), measures age, behavioral state, heart rate, oxygen saturation, and facial expression to generate a score from 0 (no pain) to 18 (maximum pain) in term infants.
RESULTS: The median pain scores were lowest with breastfed infants (DAN=1 and PIPP=4.5). The next-lowest median scores were in infants receiving sucrose and pacifier (DAN=3 and PIPP=4). Infants held in their mothers’ arms and those given sterile water had similar median pain scores (DAN=10 and PIPP=13, and DAN=10 and PIPP=12, respectively).
Pain scores in breastfed infants were significantly lower (P<.0001) as measured by both scales than in those who were held without breastfeeding and those who received sterile water. There was a nonsignificant trend towards lower pain scores in breastfed infants when compared with those receiving sucrose and a pacifier.