Monitoring of heart pumping function in healthy volunteers using impedance plethysmography

The main objective of this paper is to measure the heart pumping function continuously and with maximally non-invasive methodology in a medical setting arrangement. Thus this paper is aimed to determine the study of impedance plethysmographic method to evaluate the stroke volume changes. To obtain this, the plethysmographic device (i.e.) the hardware circuit is developed with the input current source of 100mv (peak-peak) and 10 kHz frequency. The signal obtained is amplified and it is measured in terms of voltage (i.e.) the single frequency current with the constant amplitude. The electrical impedance waveform is obtained by fitting the electrodes (Ag/Agcl) in the forearm. The peak amplitude is measured with the impedance variation inside the body. Additionally, the blood flow is analyzed with the help of fuzzy logic tool box with various activities such as Dehydration, Physical exercise, Cool skin, Warm Skin and breathe hold activity. Immediately after measuring the blood flow with the help of Impedance plethysmography, the end systolic and end diastolic values are obtained with the help of echocardiogram for the 18 subjects both in the normal condition and immediately after holding the breathe for 25 seconds. For the 18 subjects the correlation coefficient is obtained in a linear fashion between the changes in peak amplitude of forearm impedance plethysmographic waveform and changes in stroke volume before and after the 25 second breathe holding activity. Finally the forearm impedance plethysmographic waveform can be used to analyze the heart beat changes in the heart stroke volume. The process could be monitored for the series of cycles in determining the heart pumping performance.