Preterm infants' sympathetic arousal and associated behavioral responses to sound stimuli in the neonatal intensive care unit.
OBJECTIVE
To evaluate the utility of skin conductance (SC) as a measure of autonomic arousal to sound stimuli in preterm infants.


METHODS
A pilot cross-sectional, correlations study.


METHODS
Eleven preterm infants with a mean gestational age of 31.6 weeks without anomalies or conditions associated with neurodevelopmental delay composed the sample.


METHODS
On days 5-7 of life, the following infant responses were simultaneously recorded in response to naturally occurring sound stimuli in the NICU: real-time measurements of heart rate, respiratory rate, and oxygen saturations; sympathetic-mediated sweating via SC; and behavioral responses using the Newborn Individualized Developmental Care and Assessment Program naturalistic observation. Baseline sound levels (BSL, <55 dBA) and high sound levels (HSL, >65 dBA) were measured to index patterns of response during a nonhandling period preceding care.


RESULTS
Mean heart rate during precare was directly associated with higher SC increases to sound stimuli (r[10] = 0.697, P = .017). The SC during HSL was significantly higher than that during BSL (P < .0001). Males demonstrated higher SC increases to sound stimuli than females (P = .030). Changes in SC induced by increases in sound intensity were associated with lower attention responses (r[10] = -0.92, P < .0001) and lower summated behavioral responses (r[10] = -0.59, P = .054).


CONCLUSIONS
SC provides a noninvasive, sensitive measure of sympathetic arousal that may not be apparent in behavioral cues or states, or determined by standard physiological responses alone.
Salavitabar
Arash
A
College of Medicine, School of Nursing, Department of Pediatrics, The Pennsylvania State University, Hershey, PA 17033, USA.
Haidet
Kim Kopenhaver
KK
Adkins
Cherie S
CS
Susman
Elizabeth J
EJ
Palmer
Charles
C
Storm
Hanne
H
D000704:Analysis of Variance; D001143:Arousal / Q000502:physiology*; D001784:Blood Gas Analysis; D015400:Clinical Nursing Research; D003430:Cross-Sectional Studies; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D018730:Infant Behavior / Q000502:physiology*; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007363:Intensive Care Units, Neonatal / Q000458:organization & administration; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods; D009622:Noise / Q000009:adverse effects*; D009730:Nursing Assessment / Q000379:methods* / Q000592:standards; D010414:Pennsylvania; D010865:Pilot Projects; D056152:Respiratory Rate; D012680:Sensitivity and Specificity; D012727:Sex Characteristics; D013546:Sweating / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology