Simultaneous measurements of finger-tip temperatures and blood perfusion rates in a cold environment

• Published in: Journal of thermal biology 1997-06, Vol.22 (3), p.159-167
• Main Authors: Shitzer, A., Stroschein, L.A., Sharp, M.W., Gonzalez, R.R., Pandolf, K.B.
• Format: Article
• Language: English
• Subjects: Cold-induced vasodilatation; finger-tip; laser-Doppler; phase-lag
• ISSN: 0306-4565; 1879-0992
• DOI: 10.1016/S0306-4565(97)00004-1

Simultaneous measurements of middle finger-tip temperatures and blood perfusion rates were made in hands exposed to 0°C air. Temperatures were measured by a thermocouple disk attached to the nail-bed of the finger. Blood perfusion was monitored by a laser-Doppler velocimeter probe attached to the palmar side of the finger-tip. Seven, 60–80 min long experiments were performed on 6 men. The subjects sat in a comfortable (20–22°C) environment while the test hand was inserted, at about heart level, into a small non-contacting environmental chamber. Results indicated a sharp drop in finger-tip temperature of 10.1 ± 2.0°C during the initial 2 min. The time-lag between the preceding changes in blood perfusion and the ensuing changes in temperatures was in the range of 2–7 (5.86 ± 1.73) min. Cold induced vasodilatation was typically effected by triangular-like waves indicating 3 to 20-fold gradual opening-closing changes of the arterial supply of the finger-tip. Average finger-tip temperatures (11.8–15.5°C) showed much less variability among the subjects than did average blood perfusion rates (2.8–17.0 mL b·mL t −1·hr −1). Results of this study were compared to an analytical model quantifying finger-tip temperature and good conformity was obtained.