Oscillatory variations of cutaneous blood flow in newborns using a laser Doppler flowmeter

Oscillatory variations of cutaneous blood flow were studied using laser Doppler flowmetry in 20 newborns. Simultaneous monitoring of cardiorespiratory state was also performed. The frequency and amplitude of oscillatory curve varied, even on identical skin regions in each infant. When their respiration and heart rate were irregular, the frequencies of oscillatory curves were significantly higher and with a larger amplitude than when cardiorespiratory function was regular. The frequencies of oscillatory curves at two symmetrical points of an individual were not different, but a significant difference in the oscillatory cycle was recognized at two asymmetrical points. Distributions of peak-to-peak time periods of oscillatory curves were studied in nine healthy and four sick newborns. Seven of nine healthy newborns had more than two peaks in their distributions, while only one peak with a narrowly-spread distribution was observed in the four sick newborns with almost exclusively periodic breathing throughout monitoring. In conclusion, we speculate that cardiorespiratory state and some neurogenic control affects the variations observed. In addition, the narrowly-spread distribution of each time period appeared to be an important indicator of morbidity.