著者

岩谷 眞宏

出版者

一般社団法人 日本生体医工学会

雑誌

医用電子と生体工学 (ISSN:00213292)

巻号頁・発行日

vol.20, no.4, pp.249-255, 1982-08-30 (Released:2011-03-09)

参考文献数

20

被引用文献数

3

---

Using the thermograph and other instruments, a new and noninvasive method of evaluating the skin blood flow rate has been developed. Supply of heat to the skin depends on heat transportation by blood flow, on conduction from deep tissue and on the metabolic production in the skin. On the other hand, the skin loses the heat to surroundings through radiation, evaporation and convection. The heat in each case can be expressed as a function of temperature. In a comfortably air-conditioned room, there is little change in the skin temperature. Therefore, the heat flowing into the skin is presumed to equilibrate the heat flowing out. Rearranging these equations, the formula for the skin blood flow rate is obtained. For calculation, skin temperature, core temperature, ambient temperature and diameter of the leg were measured and other figures were postulated on the basis of anatomical or physiological data. Skin temperature was measured using a thermograph. Core temperature was measured by the use of deep body thermometer. Both procedures are noninvasive. Six points in a patient were subjected to the measurement. These included 10cm above the knee, 10cm below the knee and dorsum of the foot on each limb.The skin blood flow rates calculated by this method were found to be15.0±9.7ml/1009/min (n=88) on the thigh, 14.5±10ml/100g/min (n=85) on the leg and 13.3±11.0ml/100g/min (n=87) on the foot. These values corresponded well with the values reported by others, who used the plethysmographic or clearance method. The relationship between skin temperature and skin blood flow was exponential as has been pointed out by Montogomery and others. After unilateral lumbar sympathectomy in thirteen cases, the skin blood flow rate and the skin temperature on the side operated on showed statistically higher values than on the side not operated on. Especially the skin blood flow rate on the foot was higher by 50%. This fact was also compatible with previous studies on the effects of sympathectomy.As a. result, this noninvasive method of evaluating the skin blood flow is practically acceptable and will be a new addition to diagnostic armamentarium for various diseases.