A time series change of biological information through chaos analysis in finger pulse waves after taking medicine with circulatory disease

We studied effects of dosage of vasoactive medicine in chronological order by measuring the digital plethermograms. Several parameters obtained from analysis of the prethymogram were Lyapunov exponents, physical balance and autonomous activity, which have been employed to estimate the physiological changes. The results indicated that chaotic analysis could qualify the length of clinical efficacy and externalize the effect. In particular, significant difference was seen in the Lyapunov exponents obtained by measuring digital pulse waves at different times after administration. For the administration after breakfast, a significant difference (p=.0089) in Lyapunov exponents was observed between 10 minutes and 30 minutes after administration. A significant difference (p=.0325) between immediately after and 30 minutes after was also observed. For the administration after dinner, again, a significant difference (p=.0166) in Lyapunov exponents was observed between immediately after and 20 minutes after. The Lyapunov exponents increased as time elapsed from administration. We believe there is a correlation between the pulse waves and blood flow and that therapeutic efficacy can be measured by the pulse waves.