STANDARDIZATION OF PLETHYSMOGRAPHY FOR CLINICAL EXAMINATION OF PERIPHERAL BLOOD CIRCULATION

As a functional test of blood circulation, either electrocardiography or phonocardiography are essential in daily clinic. On the other hand, a plethysmography is not carried out so frequenfly, because either techniques or interpretation of results in the plethysmography differ with the examiner. In a series of the present experiment, it was planned to standardize the plethysmography as a method for examining a function of peripheral blood circulation. In the first section, experiments were performed to standardize the technique in the plethysmography.1. In a series of the experiment, a reflexion photoelectric plethysmograph was used because it was easy to handle comparing with other methods of the plethysmograph.2. A wave form of a plethysmogram was modified its shape due to a low frequency cut of the plethysmograph. If a time constant of the apparatus is over 2sec, however, the change was insignificant.3. An amplitude as well as a wave form of the plethysmogram was markedly changed due to compression a skin surface beneath the plethysmograph. It was discussed, therefore, that the plethysmograph must be attached to the skin with the pressure by which the plethysmogram showed its maximum amplitude.