Abstract:
:This paper discusses some important issues for the design of electrical impedance measurement systems intended for body fluid shift monitoring, in particular during dialysis treatments. We have studied two common signal generation systems: digital synthesis and carrier recovery. We have found that in prolonged measurement applications, digital synthesis yields the best performance. On the demodulation side, we balance the demodulator errors between the real and imaginary parts by rotating the demodulation axes. We use segmental multifrequency impedance measurements to estimate the values of intracellular and extracellular impedance by adjusting the parameters of a Cole-Cole model for each segment measured. We stress the need to perform segmental measurements in order to accurately measure the segments of interest, in particular the trunk during dialysis treatments. Our results show that there is a sharp disequilibrium between the intracellular and extracellular compartments in the very first dialysis period. This fact generates the need to continuously measure segmental impedance instead of comparing initial and final values.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Lozano A,Rosell J,Pallás-Areny Rdoi
10.1088/0967-3334/16/4/003subject
Has Abstractpub_date
1995-11-01 00:00:00pages
227-37issue
4eissn
0967-3334issn
1361-6579journal_volume
16pub_type
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