The various applications of bioelectric impedance to clinical medicine are illustrated by its use in seven patients. Detection of fluid collections in the pleura, mediastinum, and lung parenchyma; changes in cardiac output; pulsatile flow in an ischemic limb; and lower extremity venous obstruction have all been possible. Bioelectric impedance appears to have promise as a noninvasive, simple, and accurate means of monitoring vital functions.
Van De Water JM, Philips PA, Thouin LG, Watanabe LS, Lappen RS. Bioelectric ImpedanceNew Developments and Clinical Application. Arch Surg. 1971;102(6):541-547. doi:10.1001/archsurg.1971.01350060005004