An Experimental Study on Changes in Finger Blood Pressure during Chain-saw Operation
1996 年 34 巻 2 号 p. 93-100
詳細
1996 年 34 巻 2 号 p. 93-100
In this study finger blood pressure was observed by using a new method to determine if vasoconstriction activated by sympathetic nervous system takes part in changes in peripheral circulation with exposure to vibration, noise and tool weight. Finger blood pressure was measured every one minute by ambulatory monitoring system. The time profile of a single experiment consisted of 5 minutes pre-exposure period followed by one exposure period lasting 2 minutes and a post exposure period of 5 minutes. Measurement was carried out as a factorial experiment of combination of vibration (17.8 m/s2 in X-axis, 20.0m/s2 in Y-axis and 50m/s2 in Z-axis), noise (105dBA) and tool weight (7.9kg). Finger blood pressure increased significantly under the following conditions: vibration+noise+tool weight>vibration+noise_??_vibration_??_tool weight>noise_??_ control. During exposure period the combination with vibration, noise and finger grip exercise induced 29.7mmHg of increases on average in finger blood pressure. On the other hand, finger blood pressure was increased 9.5mmHg by vibration alone. These results agreed with our previous studies which observed the decreases of finger skin temperature and finger blood flow during the same conditions. The present study suggests that possible activation of the sympathetic nervous system may be involved in the physiological mechanisms of the changes in blood flow during chain-saw operation.
