Dr. Lee Baker is a Professor Emeritus in the Department of Electrical & Computer Engineering at The University of Texas at Austin.
Dr. Baker's research uses electrical impedance for the noninvasive acquisition of physiological data. The impedance technique's primary application has been to measure cardiac function (stroke volume and cardiac output) using electrodes on the surface of the thorax. Demonstrations show that values of stroke volume and cardiac output measured by the noninvasive impedance method correlate highly with values measured simultaneously by clinically acceptable invasive procedures. Despite high correlation of measurements, full clinical acceptance of the impedance technique depends upon complete understanding of the physical bases of the impedance changes during the cardiac cycle. In some medical situations (burns, thoracic surgery, traumatic emergencies) using surface electrodes is inappropriate. For such situations, one solution may be to mount an array of electrodes on a plastic tube that can be placed in the esophagus.