Overview
Project status: In progress
The measurement of cardiac output is an essential aspect of haemodynamic monitoring of patients with heart disease or patients recovering from various forms of cardiovascular disease and medical intervention including the rehabilitation of patients over extended periods of time.
- Research team
- QUT
- Organisational unit
- Lead unit Science and Engineering Faculty
- Research area
- Physics
Associate Professor Bruce Cornish
Adjunct Associate Professor Brian ThomasDetails
Changes in tissue/fluid volume, associated with the cardiac cycle, are determined based on the measurement of the electrical impedance using electrodes on the body surface, typically the thorax.
Illustrating appropriate frequencies from which to estimate stroke volume than the more commonly used single frequencies.
Impedance cardiography is a non-invasive technique for the measurement of stroke volume and cardiac output. Changes in tissue/fluid volume, associated with the cardiac cycle, are determined based on the measurement of the electrical impedance using electrodes on the body surface, typically the thorax.
A multiple frequency, alternating current is applied to the thorax and passes through both the intra- and extra-cellular fluid compartments in a ratio which is dependent on the tissue conduction characteristics and the frequency. As the current at zero frequency (or DC) only passes through the extracellular fluid and is not dependent on the capacitance of cell membranes, and since plasma is essentially extracellular fluid, this provides a more appropriate frequency from which to estimate stroke volume than the more commonly used single frequencies.
Publications and output
Gaw RL, Cornish BH, Thomas BJ, 'Comparison of a theoretical impedance model with experimental measurements of pulsatile blood flow.'Proceedings of 13th International Conference on Electrical Bioimpedance, Graz. 2007: 32,35 (DEST classification E1).
