Frequency characteristics of the electrical conductivity in normal and coagulated blood
The electrical conductivity and phase shift of normal and coagulated blood sampled from 10 pigs were measured using an LCR meter, Agilent 4285A. The hematocrit of normal blood was also measured. The conductivity difference between normal and coagulated blood remained at 4.3 mS/cm up to 800 kHz, and then gradually decreased. The conductivity difference was not correlated with the hematocrit (correlation coefficient = 0.04). The phase difference between normal and coagulated blood reached the maximum, -13.5 degree, between 1 and 2 MHz. Therefore, it is possible to discriminate thrombi from air emboli using the phase difference at the frequency range of 1 to 2 MHz.
KeywordsPhase Difference Impedance Change Agilent 4285A Electrical Impedance Measurement Conductivity Difference
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- 1.Nebuya S, Brown BH et al. (1999) Measurement of high frequency electrical transfer impedances from biological tissues. Electron Let 35-23:1–2Google Scholar
- 4.Geselowitz DB (1971) An application of electrocardiographic lead theory to impedance plethysmography. IEEE Trans Bio-med Eng 18:38-41Google Scholar