- Bioimpedance
In
biomedical engineering , bioimpedance is a term used to describe the response of a living organism to an externally applied electric current. It is a measure of the oppostion to the flow of that electric current through the tissues, the opposite ofelectrical conductivity . The measurement of the bioimpedance (or bioelectrical impedance) of the humans and animals has proved useful as a non-invasive method for measuring such things as blood flow (often referred to as bioimpedance plethysmography) and body composition (known asbioelectrical impedance analysis or simply BIA).In bioimpedance plethysmography, the measure is sometimes based on
pulsatile blood volume changes in theaorta . Bioimpedance is relevant to the development of devices to measurecardiac output and circulatingblood volume . Electrical conductivity can vary as a result of breathing. Because of this and other sources of variability, the reliability of bioimpedance for obtaining accuratedata has been called into question. Nevertheless, the technique is used in both routine clinical medicine and research.BIA has found a much sounder footing and is the basis of a number of commercially available body composition analysers. See
Bioelectrical impedance analysis for more details."All of the
information in this article above came from personalcommunication (2005) withUniversity of Southern California biomedical engineering lecturer Jean-Michel I. Maarek,Ph.D. ." Subsequently modified by Dr Leigh Ward of the University of Queensland with the assistance of Dr Scott Chetham, Impedimed Ltd, who maintains the bioimpedance information site Bioimpedance Analysis Electronic Media Review [http://florey.biosci.uq.edu.au/BIA/index.html] and is the Australasian representative for the International Society for Electrical Bioimpedance.Links
[http://www.isebi.org/ International Society For Electrical Bio-Impedance]
[http://florey.biosci.uq.edu.au/BIA/index.html Bioimpedance Analysis Electronic Media Review]
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