Journal ArticleDOI
Some aspects to the pulsation error in blood-flow calculations by indicator-dilution techniques.
Reads0
Chats0
TLDR
The results show that the pulsatile error portion of the total error of the indicator dilution methods can be kept <1% with certain conditions which are determined in the paper.Abstract:
For the calculation of blood volumes by indicator-dilution techniques, the assumption of a steady blood flow is usually made, neglecting the pulsatile character of the flow. A theoretical and experimental analysis of the error reveals whether this assumption leads to a considerable loss of accuracy or not. These studies neglect the effects of recirculation, indicator loss and poor mixing. The results show that the pulsatile error portion of the total error of the indicator dilution methods can be kept <1% with certain conditions which are determined in the paper.read more
Citations
More filters
Journal ArticleDOI
X-ray videodensitometric methods for blood flow and velocity measurement: a critical review of literature.
TL;DR: An extensive survey of English-language publications on the subject of roentgen-videodensitometric blood flow and velocity measurement from digital x-ray angiograms and a classification of published algorithms are presented.
Journal ArticleDOI
Method of assessing the reproducibility of blood flow measurement: factors influencing the performance of thermodilution cardiac output computers.
TL;DR: There was generally a deterioration in performance when pulsatile flow was evaluated, and under the conditions of the experiment optimum performance in both flow modes was obtained with 5 ml of ice cold injectate, but these findings cannot necessarily be extrapolated to the clinical situation.
Journal ArticleDOI
Simultaneous measurement of cardiac output by thermodilution, thoracic electrical bioimpedance and Doppler ultrasound
TL;DR: To evaluate the accuracy of two non-invasive techniques for cardiac output (CO) measurement, CO is measured simultaneously by thoracic electrical bioimpedance (TEB), pulsed Doppler ultrasound (DU) and standard thermodilution methods (TD) under different clinical conditions.
Journal ArticleDOI
Comparison of a two-compartment model and distributed models for indicator dilution studies.
E. A. von Reth,Jan M. Bogaard +1 more
TL;DR: This study investigated whether the two-compartment approach could be used in experimental situations as encountered in nonsteady blood flow during artificial ventilation and concluded that in this skewness range the ratio of the slopes of the ascending and descending limbs at the inflection points of a curve gives an estimate of the time-constant ratios of the compartments of the compartment model.
Journal ArticleDOI
The volume-dependency of parallel conductance throughout the cardiac cycle and its consequence for volume estimation of the left ventricle in patients
TL;DR: To obtain stroke volume or to determine absolute left ventricular volume continuously within a cardiac cycle, G( p) should be determined throughout each cardiac cycle and if a constant G(p) throughout the cardiac cycle is used a correction with the factor alpha should be made to correct for a possible influence of electrical field heterogeneity.
References
More filters
Journal ArticleDOI
Limitations of thermal dilution curves for cardiac output determinations.
Journal ArticleDOI
Ventricular Nonmixing as a Source of Error in the Estimation of Ventricular Volume by the Indicator-Dilution Technic
H. J. C. Swan,Walter Beck +1 more
TL;DR: Incomplete mixing of the left artial blood with the residual volume of the ventricle precludes accurate quantitation of the changes of volume in the ventricular volume by the simple formulas proposed by previous authors.
Journal ArticleDOI
Theoretical Considerations and Model Experiments on the Validity of Indicator Dilution Methods for Measurements of Variable Flow
Gerd J. A. Cropp,Alan C. Burton +1 more
TL;DR: This investigation suggests from theory and experiments in models that under the right conditions a modified method of calculation can be used to measure variable pulsatile flow by indicator dilution techniques.
Journal ArticleDOI
Mixing and observation errors in indicator-dilution studies.
Journal ArticleDOI
Analysis of indicator distribution in the determination of cardiac output by thermal dilution.
TL;DR: The distribution of thermal indicator of room temperature from its introduction into the injection catheter until its detection by a thermistor in the pulmonary artery has been analysed and the equations for calculating cardiac output have been derived and verified experimentally.
Related Papers (5)
Theoretical Considerations and Model Experiments on the Validity of Indicator Dilution Methods for Measurements of Variable Flow
Gerd J. A. Cropp,Alan C. Burton +1 more