[Respiration-dependence of cutaneous laser Doppler flow motion]

The aim of this study was to show and to quantify the breath-dependency of cutaneous fluxmotion in the volar proximal forearm using a new computer-aided system. A meanflux-related index (MI) representing the intensity of the influence of respiration on fluxmotion was calculated. There was a good correlation between MI and the rate of respiration under spontaneous breathing: the lower the rate of respiration, the higher the value of MI. Prescribing a constant breathing rhythm amplifies this frequency-dependent effect. According to occurrence of low rates of respiration (< 12/min) also under physiological conditions the respiration should be simultaneously recorded while assessing fluxmotion.