CHANGES IN LASER-DOPPLER FLUX AFTER LOCAL COOLING OF THE HAND IN NEWBORN-INFANTS

Background: Using laser-Doppler fluxmetry we studied the influence of local cooling on the cutaneous microcirculation of the hand in newborn infants. Methods: In 18 neonates, gestational age 26-39 weeks - we measured laser-Doppler flux and skin temperature of the palm simultaneously during local cooling. Results: After 20 minutes of cooling, skin temperature changed from 35.1 degrees to 24.0 degrees C. At the same time there was a significant reduction in laser-Doppler flux from 221.6 to 76.8 AU (p = 0.0001). We observed different patterns of vasomotions: Most infants showed a reduction of flowmotions and oscillatory amplitudes with decreasing laser-Doppler flux signals. There was a significant correlation between skin temperature and laser-Doppler flux (r = 0.63, p < 0.0001). Conclusion: Premature and mature infants showed similar changes in laser-Doppler flux after local cooling of the hand as described in adults. Laser-Doppler fluxmetry seems to be a suitable method for assessing thermoregulatory functions of the cutaneous microcirculation in newborn infants.