Post-prandial effects in reactivity of forehead and mid-femoral skin blood flow and heart rate in neonates.
The effect of post-prandial period on the cutaneous vascular reactivity was studied in twelve full-term infants on their 3rd postnatal day. The differences in vasomotor reactions between the forehead and femoral skin were also investigated. Two 10-min control registrations about 30 and 90 min after feeding were followed by a registration of equal duration during thermal stimulation of the skin. The lower extremity of each infant was stimulated by warm and cool air currents (5 cycles/min) to induce periodic vasomotor changes. The fast Fourier transform was used to compute variability spectra for the recorded skin blood flow, heart rate and respiratory wave form signals. The skin blood flow became synchronised to the thermal stimulation in both skin regions. Neither the spontaneous nor synchronised oscillations of the skin blood flow differed significantly between femoral skin and forehead. The post-prandial time did not have any influence on this synchronisation. Heart rate variability was synchronised to the periodicity of thermal stimulation more 1.5 h after feeding than 0.5 h after feeding. Respiration was not affected. The results show that increasing post-prandial time has no influence on the synchronised oscillations of skin blood flow. However, it potentiates reactivity of heart rate to perturbations in the peripheral vasculature.
Jahnukainen
T
T
Cardiorespiratory Research Unit, University of Turku, Finland.
Lindqvist
A
A
Vuorinen
M
M
Jalonen
J
J
Välimäki
I
I
D001831:Body Temperature / Q000502:physiology; D004435:Eating / Q000502:physiology*; D005546:Forehead; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D012039:Regional Blood Flow / Q000502:physiology; D012867:Skin / Q000098:blood supply*; D017550:Spectroscopy, Fourier Transform Infrared; D013223:Statistics as Topic; D013848:Thigh; D013997:Time Factors