Vol. 85, Issue 2, 459-464, August 1998
Cardiac output and mixed venous
O2 content measurements by a
tracer bolus method: animal validation study
Justin S.
Clark,
Yuxiang J.
Lin,
Michael J.
Criddle,
Roger
Jones,
Erik
Koppert, and
Patrick
Swier
Department of Biomedical Engineering and Medical Physics, LDS
Hospital, Salt Lake City 84103; Department of Medical Informatics,
University of Utah, Salt Lake City 84132; and Anesthesiology Department
of Primary Children's Medical Center, Salt Lake City, Utah 84113
A bolus method for
noninvasive measurement of cardiac output (CO) and mixed venous oxygen
content
(
O2)
has been tested against absolute CO and
O2
standards in dogs. No statistical differences in CO were found
between bolus method and electromagnetic flowmeter measurement
comparisons in an 18-dog study in which CO varied from 0.5 to 3.0 l/min. The SD for all paired differences was 0.14 l/min; however, data
averaging over 10-min intervals were found to reduce the CO measurement
uncertainty to <0.08 l/min. The ability of the bolus method to follow
rapid CO changes, experimentally produced by control of a pump
(surgically placed between the superior and inferior vena cava
and the right atrium), was documented and found to satisfy CO
monitoring requirements of unstable subjects. O2
bolus values were found to be statistically equivalent to reference
measurements.
multiple inert gas; dogs
