Newborns experience less pain during a heel prick if they are played with soothing music than if they are in a quiet room, according to research conducted at Lincoln Hospital in New York.
The authors of the work, who presented their results yesterday in the journal Pediatric Research, propose that music "is an easy, reproducible and cheap tool to relieve pain in healthy newborns" and that "it can be applied in neonatology units with resources limited (...) potentially worldwide”.
Previous studies had suggested that music could have an analgesic effect on premature babies. The new research is the first to evaluate the efficacy of music to relieve pain in newborns in a clinical trial with a similar design to those evaluating the efficacy of drugs.
It has been carried out with one hundred full-term babies who underwent the heel test, which consists of extracting a blood sample from the foot for the early detection of hereditary diseases such as cystic fibrosis or phenylketonuria.
Half of them were tested with music by Mozart selected from the Classical Lullabies for Babies album. “This piece was chosen for its minor tones and its sedative effect,” explain the researchers in Pediatric Research.
The other half were tested without music.
All babies also received 0.5 milliliters of a sugar solution two minutes before the test, which is the standard method of non-drug pain relief for infants at Lincoln Hospital.
To ensure that the study assessed the effect of music on the children and not on the health personnel conducting the test, doctors and nurses wore headphones with other music, so they could not tell whether Mozart's lullaby was playing or not when they did the test.
Babies' pain was assessed using the NIPS (Neonatal and Infant Pain Scale) scale. This scale assesses six types of reactions (facial expression, crying, breathing, arm movements, leg movements and state of arousal) and offers a result from 0 to 7, where 0 indicates no pain and 7 indicates very intense pain.
Among the newborns who were tested in silence, pain registered a mean value of 6.5 at the moment of the prick, while among those who listened to Mozart's lullaby a value of 4.5 was registered (which It is considered moderate to severe pain).
One minute later, the pain had subsided in both groups. But it remained at 4.5 among those who had endured the test in silence and had dropped to 2.5 (considered mild pain) for those who continued to listen to music.
Three minutes after the puncture, the majority of the babies who returned registered a value of 0 (no pain) in both groups.
The reason why music has an analgesic effect is that it "modulates the response to pain by causing sensory saturation," the authors of the research propose. This effect “leads to the blockage of the pain circuit, to distraction and to an alteration of the perception of pain”.
Neonatologists at Lincoln Hospital warn that "pain in newborns has been underestimated for decades" and that "newborns experience an exaggerated response to pain due to immaturity of their nervous system and inhibitory circuitry."
Music, they point out, can be useful to improve children's well-being during routine medical procedures in pediatric units such as intramuscular injections and blood draws. In addition to music, other non-pharmacological interventions that relieve pain in newborns include sugar, breastfeeding, and parental skin contact.
