Heart rate variability in response to pain stimulus in VLBW infants followed longitudinally during NICU stay.

The objective of this longitudinal study, conducted in a neonatal intensive care unit, was to characterize the response to pain of high-risk very low birth weight infants (<1,500 g) from 23 to 38 weeks post-menstrual age (PMA) by measuring heart rate variability (HRV). Heart period data were recorded before, during, and after a heel lanced or wrist venipunctured blood draw for routine clinical evaluation. Pain response to the blood draw procedure and age-related changes of HRV in low-frequency and high-frequency bands were modeled with linear mixed-effects models.

The behavioral pain response to heelstick in preterm neonates studied longitudinally: description, development, determinants, and components.

Objectives: Preterm infants often experience multiple painful procedures during their stay in neonatal intensive care units (NICUs). The objectives of this study were to evaluate behavioral responses to heelstick in preterm newborns, characterize developmental changes and the effects of other demographic and clinical variables on the pain response, and estimate the contributions of individual Neonatal Infant Pain Scale (NIPS) behaviors to the summary pain score.

Methods: A longitudinal study was conducted to evaluate the behavioral responses of 35 preterm newborns to multiple heelstick procedures during their stay in the NICU.

A comparison of fetal and neonatal heart rate variability at similar post-menstrual ages.

Substantial differences of heart rate variability (HRV) were found between fetuses and prematurely born neonates in the high-frequency band of the power spectrum. The range of post-menstrual ages of the fetuses and neonates were closely matched in this study. Growth of HRV was observed in low-frequency and high-frequency bands, reflecting maturation of the autonomic nervous system.

Longitudinal assessment of heart rate variability in very low birth weight infants during their NICU stay.

Background: Maturation of the autonomic nervous system has not been studied in high-risk very low birth weight (VLBW) infants in the first few weeks of life.

Aim: To characterize developmental changes in autonomic nervous system activity of high-risk VLBW infants from 23 to 38 weeks post-menstrual age by measuring heart rate variability (HRV).

Study Design And Subjects: In this prospective cohort study 38 infants admitted to Children's Memorial Hermann Hospital NICU were longitudinally followed weekly or biweekly.