REACTIVITY OF SKIN BLOOD-FLOW AND HEART-RATE TO THERMAL-STIMULATION IN INFANTS DURING THE FIRST POSTNATAL DAYS AND AFTER A 2-MONTH FOLLOW-UP

The reactivity of skin blood flow and heart rate to periodic thermal s timulation was studied in 10 term small-for-gestational age (SGA) infa nts, in 9 preterm and 8 term normal-sized infants during the first two postnatal months. During the first postnatal days, the increase in th ermally stimulated skin blood flow oscillations was absent in SGA infa nts but was clearly present in both preterm (p < 0.01) and term (p < 0 .01) normal-sized infants. The responsiveness of SGA infants improved during the follow-up (p < 0.05). The response of the periodic heart ra te variability of SGA and preterm infants was inferior to term normal- sized infants until the age of 2 months. The cardiovascular responsive ness of growth-retarded infants seems abnormal during the first days o f life, and may impair their ability to meet stress, e.g. changes of a mbient temperature.