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PubMed1990

[Physical and biophysical aspects of high energy intracardiac electrical discharges. II. Correlations between the physical and electrical effects of liminal and infraliminal shocks].

The electrical phenomena produced during the fulguration impulses are analyzed using a digital oscilloscope which enables the calculation, with precision, of the energies consumed all along the curve or between chosen times. Moreover, it enables the calculation of the corresponding impedance values and shows that the latter varies during all the discharge. The explanation for these impedance variations is obtained thanks to rapid cinematography, showing the formation of the fulguration bubble. Hence, one can observe an impedance variation which is quite distinctive from the one which would correspond to the simple passage of an electrical current in saline solution. Particularly at the end of the impulse, an important increase in the impedance corresponds to the loss of ionization of the bubble. Therefore, by simply reading these electrical parameters, it is possible to know the main stages of the fulguration phenomenon for impulses situated around the deflagration threshold.

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PubMed1990

[Physical and biophysical aspects of high-energy intracardiac electric discharges. III. Correlation between physical and electric effects for the use of supraliminal shocks].

Using the same methods as for the measurement of electrical parameters by means of an oscilloscope with a wave shape calculator to determine at all points the energy and impedance values, as well as high speed cinematography, the analysis of the behavior of these parameters for shocks with energies close to those used in clinical medicine can be carried out. It shows namely an important decrease in the impedance at the current peak due to an important ionization of the fulguration bubble. It underlines the different behavior of the anode and cathode bubbles, in relation with the size of the bubbles obtained thanks to rapid cinematography. Comparative measurements concerning the polarity, the size of the indifferent electrode, the medium used in vitro and in vivo have supplied the elements to enable the precise determination of the adequate electrical parameters for the good use of fulguration.

Animals↗