Abstract
In order to make clear the circulatory changes in the lower limbs in pregnancy, the author made records (587 cases) of the toe and finger plethysmogram of the normal pregnant, nonpregnant and puerperal women. The author classified these plethysmograms into two categories such as catacrotic wave, dilated ware as normal and sclerotic rigid wave as abnormal.
There are no differences between pregnant, nonpregnant and puerperal women about appearance rate of the abnormal wave in the toe plethysmogram. In the finger plethysmogram, there are remarkable lower appearance rate of the abnormal wave in the normal pregnant women compared to nonpregnant and puerperal women. These seemed to be influenced by the vascular elasticity, blood viscocity and the resistance of the peripheral blood vessels in pregnancy.
The essential differences between toe and finger plethysmogram is yet unknown.
The analytical studies on these plethysmogram were done about three indexes as following such as ratio botween up-stroke time and height of the wave (I. I.), ratio between arterial blood supply time and height of the wave (Ej. I.) and ratio between down-stroke time and height of the wave (De. I.) . On the I. I. of the toe and finger plethysmogram there are no differences between pregnant, noopregnant and puerperal women. Ej. I. of the toe plethysmogram is remarkably longer than that of the finger plethysmogran. Ej. I. of the toe plethysmogram before birth is longer than that after birth. The toe plethysmogram with 70 mmHg compression on the thigh is equivalent to the toe plethysmogram of the full term pregnancy without any compression.
The conduction time of the toe plethysmogram is about 0.30 sec before birth but after birth the conduction time is 0.28-0.27 sec. These seemed to be due to congestion and prolongation of the time of the arterial blood flow by the compression of the pregnant uterus.
