PMID- 9292477
OWN - NLM
STAT- MEDLINE
DCOM- 19971014
LR  - 20171213
IS  - 8750-7587 (Print)
IS  - 0161-7567 (Linking)
VI  - 83
IP  - 3
DP  - 1997 Sep
TI  - Cardiac output and mixed venous oxygen content measurements by a tracer bolus 
      method: theory.
PG  - 884-96
AB  - We present a bolus method of inert-gas delivery to the lungs that facilitates 
      application of multiple inert gases and the multiple inert-gas-exchange technique 
      (MIGET) model to noninvasive measurements of cardiac output (CO) and central 
      mixed venous oxygen content Reduction in recirculation error is made possible by 
      1) replacement of sinusoidal input functions with impulse inputs and 2) 
      replacement of steady-state analyses with transient analyses. Recirculation error 
      reduction increases the inert-gas selection to include common gases without 
      unusually high (and difficult to find) tissue-to-blood partition coefficients for 
      maximizing the systemic filtering efficiency. This paper also presents a 
      practical method for determining the recirculation contributions to inert expired 
      profiles in animals and determining their specific contributions to errors in the 
      calculations of CO and from simulations applied to published 
      ventilation-perfusion ratio (V/Q) profiles. Recirculation errors from common 
      gases were found to be reducible to the order of 5% or less for both CO and 
      whereas simulation studies indicate that measurement bias contributions from 
      recirculation, V/Q mismatch, and the V/Q extraction process can be limited to 15% 
      for subjects with severe V/Q mismatch and high inspired oxygen fraction levels. 
      These studies demonstrate a decreasing influence of V/Q mismatch on parameter 
      extraction bias as the number of inert gases are increased. However, the 
      influence of measurement uncertainty on parameter extraction error limits 
      improvement to six gases.
FAU - Clark, J S
AU  - Clark JS
AD  - Department of Biomedical Engineering and Medical Physics, LDS Hospital, Salt Lake 
      City 84103, USA.
FAU - Lin, Y J
AU  - Lin YJ
FAU - Criddle, M J
AU  - Criddle MJ
FAU - Cutillo, A G
AU  - Cutillo AG
FAU - Bigler, A H
AU  - Bigler AH
FAU - Farr, F L
AU  - Farr FL
FAU - Renzetti, A D Jr
AU  - Renzetti AD Jr
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Appl Physiol (1985)
JT  - Journal of applied physiology (Bethesda, Md. : 1985)
JID - 8502536
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - Animals
MH  - Cardiac Output/*physiology
MH  - Computer Simulation
MH  - Dogs
MH  - Female
MH  - Male
MH  - Microcirculation/physiology
MH  - Models, Biological
MH  - Oxygen/*blood
MH  - Respiration, Artificial
MH  - Ventilation-Perfusion Ratio/physiology
EDAT- 1997/09/18 00:00
MHDA- 2001/03/28 10:01
CRDT- 1997/09/18 00:00
PHST- 1997/09/18 00:00 [pubmed]
PHST- 2001/03/28 10:01 [medline]
PHST- 1997/09/18 00:00 [entrez]
AID - 10.1152/jappl.1997.83.3.884 [doi]
PST - ppublish
SO  - J Appl Physiol (1985). 1997 Sep;83(3):884-96. doi: 10.1152/jappl.1997.83.3.884.