Personal perspectives: Infant pain-A multidisciplinary journey.

Understanding of infant pain has been transformed in the past 30 years. From assumptions that newborns were insensitive to pain, fundamental work established not only the infants perceive pain, but also there are critical windows in which pain can have long-lasting consequences. My multidisciplinary work revealed that repetitive pain exposure during the late 2nd and 3rd trimesters of fetal life "ex-utero" in infants born very preterm is related to long-term adverse associations with altered brain development, programming of stress systems, and thereby neurodevelopment.

Neonatal pain in very preterm infants: long-term effects on brain, neurodevelopment and pain reactivity.

Effects of early life psychosocial adversity have received a great deal of attention, such as maternal separation in experimental animal models and abuse/neglect in young humans. More recently, long-term effects of the physical stress of repetitive procedural pain have begun to be addressed in infants hospitalized in neonatal intensive care. Preterm infants are more sensitive to pain and stress, which cannot be distinguished in neonates.

Pain reactivity in 2-month-old infants after prenatal and postnatal serotonin reuptake inhibitor medication exposure.

Objective: In this prospective study, we examined biobehavioral responses to acute procedural pain at 2 months of age in infants with prenatal and postnatal selective serotonin reuptake inhibitor (SSRI) medication exposure. Based on previous findings showing reduced pain responses in newborns after prenatal exposure, we hypothesized that altered pain reactivity would also be found at 2 months of age.

Methods: Facial action (Neonatal Facial Coding System) and cardiac autonomic reactivity derived from the respiratory activity and heart rate variability (HRV) responses to a painful event (heel-lance) were compared between 3 groups of infants: (1) infants with prenatal SSRI exposure alone (n = 11; fluoxetine, n = 2; paroxetine, n = 9); (2) infants with prenatal and postnatal SSRI (via breast milk) exposure (total n = 30; fluoxetine, n = 6; paroxetine, n = 20; sertraline, n = 4); and (3) control infants (n = 22; nonexposed) during baseline, lance, and recovery periods.

Does prone or supine position influence pain responses in preterm infants at 32 weeks gestational age?

Objective: The purpose of this study was to examine the influence of prone and supine position in preterm infants during acute pain of blood collection.

Setting: Level III Neonatal Intensive Care Unit (NICU).

Study Design: Thirty-eight preterm infants (birthweight 1339 [590-2525] g, GA 29 [25- 32] wks) were in 2 groups depending on their position in the isolette prior to and during heel lance at 32 weeks post-conceptional age.

Are there developmentally distinct motor indicators of pain in preterm infants?

The aims of this study were to examine preterm infant reactions to pain in detail over prolonged time periods using multiple measures, and to assess the value of including specific body movements of the Neonatal Individualized Developmental Care and Assessment Program (NIDCAP) system to evaluate pain. Ten preterm infants born at 31 weeks mean gestational age (GA) and mean birth weight 1676 g were studied during a routine blood collection in a Level III neonatal intensive care unit (NICU). At 32-week post-conceptional age, computerized physiologic and video recordings were obtained continuously for 60 min (prior to, during and after lance).

Pattern of learning disabilities in children with extremely low birth weight and broadly average intelligence.

Objectives: To examine the prevalence and pattern of specific areas of learning disability (LD) in neurologically normal children with extremely low birth weight (ELBW) (< or = 800 g) who have broadly average intelligence compared with full-term children with normal birth weight of comparable sociodemographic background, and to explore concurrent cognitive correlates of the specific LDs.

Design: Longitudinal follow-up; geographically defined region.

Setting: Regional follow-up program.

Prolonged prenatal psychotropic medication exposure alters neonatal acute pain response.

Selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines are frequently used to treat maternal depression during pregnancy, however the effect of increased serotonin (5HT) and gamma-amino-butyric acid (GABA) agonists in the fetal human brain remains unknown. 5HT and GABA are active during fetal neurologic growth and play early roles in pain modulation, therefore, if prolonged prenatal exposure alters neurodevelopment this may become evident in altered neonatal pain responses. To examine biologic and behavioral effects of prenatal exposure, neonatal responses to acute pain (phenylketonuria heel lance) in infants with prolonged prenatal exposure were examined.

Bedside application of the Neonatal Facial Coding System in pain assessment of premature neonates.

Assessment of infant pain is a pressing concern, especially within the context of neonatal intensive care where infants may be exposed to prolonged and repeated pain during lengthy hospitalization. In the present study the feasibility of carrying out the complete Neonatal Facial Coding System (NFCS) in real time at bedside, specifically reliability, construct and concurrent validity, was evaluated in a tertiary level Neonatal Intensive Care Unit (NICU). Heel lance was used as a model of procedural pain, and observed with n = 40 infants at 32 weeks gestational age.

Judging pain in infants: behavioural, contextual, and developmental determinants.

Caretakers intuitively use various sources of evidence when judging infant pain, but the relative importance of salient cues has received little attention. This investigation examined the predictive significance for judgements of painful discomfort in preterm and full-term neonates of behavioural (facial activity and body movement), contextual (invasiveness of the procedure), and developmental (gestational age) information. Judges viewed videotapes showing infants varying in the foregoing characteristics undergoing heel incisions for routine blood sampling purposes.