T. Jahnukainen et al., DYNAMICS OF VASOMOTOR THERMOREGULATION OF THE SKIN IN TERM AND PRETERM NEONATES, Early human development, 33(2), 1993, pp. 133-143
Eighteen fullterm infants and 17 preterm infants were studied on their
3rd day of life to investigate the reactivity of skin blood flow to t
hermal stimulation. The infants were studied during quiet sleep. After
a 10-min control period a constant air current was used to synchronis
e the external cutaneous stimulus to the distal lower extremity of eac
h infant: the heating element of an air blower was automatically switc
hed on and off to generate successive warm and cool periods of equal d
uration (5 cycles/min). Heart rate (HR), skin blood flow (SBF) and res
piratory waveform signals were recorded and their variability was anal
ysed using the fast Fourier transform and spectral analysis. Fullterm
infants showed a clear response to external thermal stimulation: both
HR and SBF were synchronised to the stimulation frequency. A response
of preterm infants was present but it was markedly attenuated in compa
rison to term infants. The effect of stimulation did not seem to be de
pendent on postnatal age. The results suggest that the vasomotor contr
ol is immature in preterm infants.