Thoracic electrical bioimpedance: a non-invasive measure of cardiac output for porcine research.
A comparison of two techniques for measuring cardiac output, thermodilution (TD) and thoracic electrical bioimpedance (TEB), was undertaken in a porcine model. Eight anaesthetized large white pigs were studied. A total of 436 paired measurements were performed over a range of cardiac outputs from 1.7 to 15.1 l/min as measured by thermodilution. The Pearson product moment correlation coefficient was r = 0.963 with P < 0.001. Analysis by Bland and Altman statistics revealed a mean difference (bias) of -0.02 l/min and the limits of agreement were +/- 1.6 l/min, similar to figures found in human comparative studies. These results confirm that thoracic electrical bioimpedance is a valid method of measuring cardiac output in pigs. It has significant advantages compared to thermodilution, in particular it is cheap, simple to use, non-invasive and provides continuous data.
Broomhead
C J
CJ
Sir Henry Souttar Research Laboratories, Royal Hospitals Trust, The Royal London Hospital, London, UK.
Wright
S J
SJ
Kiff
K M
KM
Withington
P S
PS
D000818:Animals; D002302:Cardiac Output; D002307:Cardiography, Impedance; D005260:Female; D013552:Swine / Q000502:physiology*; D013815:Thermodilution