Inspiratory behavioral differences among newborn infants
Creators: name: Smith, Bonnie Kay
Publisher: name: University of Utah
Year: 2012

description: The purpose of this study was to investigate the inspiratory behaviors of newborn infants in order to provide a more comprehensive evaluation of newborn behavior.  The study of developmental behavior has always been of interest to researchers in child development, and nurse-caretakers now appreciate more fully the value of understanding development in planning care for their youngest clients.  Inspiratory behaviors of newborn infants, which this investigator considers a developmental behavior with genesis early in fetal life, is not clearly described in either medical or nursing literature.  As with any developmental behavior, the evolution of inspiratory behavior is influenced by innumerable genetic and environmental factors pre- and post-natally, which facilitates, hinders, or alters its expression.  These factors form the basis for behavioral differences.  Brazelton and Rosenblith have each devised scales for measuring behavioral differences among newborn infants.  However, neither of these assessment tools specifically assess inspiratory behavior, although they do include the ability of the infant to defend his nose and mouth from obstructive materials placed over them.  The main focus of this study, then, was to determine if newborn infants vary in the use of diaphragm and of intercostal muscles during the inspiratory phase of respiration.  Additional information was gathered during the assessment period regarding maternal history, the pregnancy, labor, delivery, and physical status of the child.  The general maturational portion of the Rosenblith/-Graham scale was used to assess each infant's defensive responses to materials placed over his nose and mouth, and his ability to free his face when placed in a prone position.  These data were gathered to consider possible relationships between inspiratory behavior and other variables.  Subjects for the study were one hundred normal newborn infants born at Cottonwood Hospital.  Each infant was assessed for presence, location, and strength of activity of intercostal muscles and diaphragm. Defensive behaviors, including persistence and vigor of responses, were also determined.  A research assistant recorded scores as the investigator examined the infants.  The assistant also recorded information from the mothers' and infants' medical charts.  No significant variation was discovered in the activity of the diaphragm.  However, variation did occur in intercostal muscle activity. Thirty-five percent of the infants were found to have some risk factors identified through information from the charts  The infants with identified risk factors as a group had lower intercostal muscle activity scores than did the non-risk group.  Male infants also had lower scores than did the female infants.  Low gestational age infants had consistently lower intercostal muscle activity than did infants with a gestational age of 38 weeks or greater.  Low intercostal muscle activity scores were associated with groups of infants which previous research has shown to have lower potential for optimal growth and development.  This gives validity for the addition of such an assessment to the existing assessment tools for eventuating newborn behavior.  Ninety-seven percent of the one hundred subjects were adequately defensive to obstructive materials placed over the nose and mouth.  Only two infants were unable to turn their heads when placed in a prone position.  No relationships were discovered between defensive responses and intercostal muscle activity.