FINGERTIP TEMPERATURE AS AN INDICATOR FOR SYMPATHETIC RESPONSES

Changes of acral skin blood flow are a commonly used indicator for sym pathetic reflex responses to various stimuli. The goal of the present study was to determine whether decreases in fingertip temperature are indicative for sympathetic induced changes in microcirculation. Infrar ed thermography demonstrated that various stimuli triggering the sympa thetic nervous system induced decreases in cutaneous microcirculation, most prominently in fingertip skin. Various such stimuli induced almo st immediate temporary vasoconstriction, measured by laser Doppler flu x and photoplethysmography. With a lag phase of approximately 15 s, re duced microcirculation was also reflected by a transient decrease in f ingertip temperature. Vasoconstrictions were easily demonstrable by fi ngertip temperature when the starting fingertip temperature was above 32 degrees C and vasoconstriction lasted at least 5 s. Temperature mea surement offers the advantages of ease and simplicity of performance a nd analysis, compared with the more complex analyses of flux and pulse volume. (C) 1998 Elsevier Science B.V.