Midttun M, Sejrsen P, Colding-Jorgensen M
Department of Medical Physiology, The Panum Institute, University of Copenhagen, Denmark.
Clin Physiol. 1996 May;16(3):259-74. doi: 10.1111/j.1475-097x.1996.tb00573.x.
A new method, the heat-washout method, for measuring total cutaneous blood flow rate is introduced. The measurements were performed with a transcutaneous (tc) PO2-electrode that is capable of heating and measuring local temperature, and it is constructed with a thermostatically controlled cap. The probe was heated electrically to a selected temperature 2-10 degrees above normal skin temperature. When the temperature was stable, the heating element was turned off, and the temperature was registered every 10 s until a stable baseline temperature, Tb, was obtained. Tb was subtracted from the registered temperatures giving deltaTs that were plotted in a semilogarithmic diagram. The heat-washout was monoexponential, and the slope was used for calculating blood flow rate in accordance with the principle of Kety, using a known partition coefficient. The method was applied to the forearm in two subjects, and the results were compared to blood flow rates obtained simultaneously by the 133Xe-washout method in the same area. The equation of the regression line was y = 2.5 + 0 x 968X and the correlation coefficient was 0 x 986 at temperature levels of 37-45 degrees C. In the pulp of the thumb, blood flow rates, in arteriovenous anastomoses, were estimated in two subjects by subtracting the capillary blood flow rate, measured by 133Xe-washout, from the total cutaneous blood flow rate, measured by heat-washout. Due to a relatively low diffusions coefficient for 133Xe compared to heat, 133Xe cannot be used for measurement of blood flow rate in arteriovenous anastomoses.
介绍了一种测量皮肤总血流速率的新方法——热洗脱法。测量是使用一种能够加热并测量局部温度的经皮（tc）PO₂电极进行的，该电极配有一个恒温控制帽。将探头电加热到比正常皮肤温度高2至10摄氏度的选定温度。当温度稳定后，关闭加热元件，每隔10秒记录一次温度，直到获得稳定的基线温度Tb。从记录的温度中减去Tb，得到ΔTs，并将其绘制在半对数图中。热洗脱呈单指数形式，根据凯蒂原理，利用已知的分配系数，通过斜率计算血流速率。该方法应用于两名受试者的前臂，并将结果与同一区域同时通过¹³³Xe洗脱法获得的血流速率进行比较。在37至45摄氏度的温度水平下，回归线方程为y = 2.5 + 0 x 968X，相关系数为0 x 986。在两名受试者的拇指指腹，通过从热洗脱法测量的皮肤总血流速率中减去¹³³Xe洗脱法测量的毛细血管血流速率，来估计动静脉吻合处的血流速率。由于¹³³Xe的扩散系数相对于热来说较低，¹³³Xe不能用于测量动静脉吻合处的血流速率。
