Cardiac output measurement by the thermodilution method: an in vitro test of accuracy of three commercially available automatic cardiac output computers. 1995

A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
Institute of Human Physiology, University of Padova, Italy.

OBJECTIVE To describe the accuracy and the reproducibility of the thermodilution flow measurements obtained using 3 commercially available cardiac output computers commonly used in intensive care units. METHODS An experimental "in vitro" study. Twelve different values of control flow (Qctr) were measured (Qmsr) using 3 different cardiac output computers (Abbott Critical Care System, Oximetrix 3 SvO2/CO Computer, Baxter Oximeter/Cardiac Output Computer SAT-1; American Edwards Laboratories, 9520 A Cardiac Output Computer). Standard equipment and techniques were employed, taking account of the specific weight and heat of warm water relative to blood. In addition, separate sets of measurements were performed in order to investigate the effect on Qmsr of some variables which may influence the "indicator" loss (time for injection, depth of immersion of the catheter, temperature of the injected fluid). METHODS Our laboratory, inside the intensive care unit. RESULTS The analysis of the linear regression of Qmsr versus Qctr (r values between 0.992 and 0.984; residual standard deviation values comprised between 0.24 and 0.49 l/min; intercepts and slopes not significantly different from identity line), the values of the percentage errors (PE = [Qctr-Qmsr].100/Qctr; PE mean values 7.9, 5.0 and 13.1), and those of the coefficients of variability (CV = standard deviation mean value, %; CV mean values 5.4, 5.8 and 4.6), show a good level of accuracy and reproducibility of the measurements. Our data confirm previously reported results. Furthermore, the cumulative effect of variables capable of influencing the "indicator" loss, even if corrected according to the "calculation constant" the manufacturers provide, was found to result in statistically significant changes of Qmsr. CONCLUSIONS The accuracy and reproducibility of the automatic cardiac computers tested is sufficient for practical clinical purpose. It may also depend on the modality of injection of the cooling bolus, which may significantly influence the effective "indicator" losses.

UI MeSH Term Description Entries
D002302 Cardiac Output The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat). Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D003201 Computers Programmable electronic devices designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations. Calculators, Programmable,Computer Hardware,Computers, Digital,Hardware, Computer,Calculator, Programmable,Computer,Computer, Digital,Digital Computer,Digital Computers,Programmable Calculator,Programmable Calculators
D004867 Equipment Design Methods and patterns of fabricating machines and related hardware. Design, Equipment,Device Design,Medical Device Design,Design, Medical Device,Designs, Medical Device,Device Design, Medical,Device Designs, Medical,Medical Device Designs,Design, Device,Designs, Device,Designs, Equipment,Device Designs,Equipment Designs
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013815 Thermodilution Measurement of blood flow based on induction at one point of the circulation of a known change in the intravascular heat content of flowing blood and detection of the resultant change in temperature at a point downstream. Thermodilutions
D015203 Reproducibility of Results The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results. Reliability and Validity,Reliability of Result,Reproducibility Of Result,Reproducibility of Finding,Validity of Result,Validity of Results,Face Validity,Reliability (Epidemiology),Reliability of Results,Reproducibility of Findings,Test-Retest Reliability,Validity (Epidemiology),Finding Reproducibilities,Finding Reproducibility,Of Result, Reproducibility,Of Results, Reproducibility,Reliabilities, Test-Retest,Reliability, Test-Retest,Result Reliabilities,Result Reliability,Result Validities,Result Validity,Result, Reproducibility Of,Results, Reproducibility Of,Test Retest Reliability,Validity and Reliability,Validity, Face
D016018 Least-Squares Analysis A principle of estimation in which the estimates of a set of parameters in a statistical model are those quantities minimizing the sum of squared differences between the observed values of a dependent variable and the values predicted by the model. Rietveld Refinement,Analysis, Least-Squares,Least Squares,Analyses, Least-Squares,Analysis, Least Squares,Least Squares Analysis,Least-Squares Analyses,Refinement, Rietveld
D066298 In Vitro Techniques Methods to study reactions or processes taking place in an artificial environment outside the living organism. In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In

Related Publications

A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
January 1978, Medical instrumentation,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
September 1977, Respiratory care,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
January 1974, Acta biologica et medica Germanica,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
July 1979, Canadian journal of surgery. Journal canadien de chirurgie,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
October 1996, Intensive care medicine,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
October 1987, Critical care medicine,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
January 1954, Quarterly journal of experimental physiology and cognate medical sciences,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
October 2000, Lab animal,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
November 1979, The Journal of thoracic and cardiovascular surgery,
A Rubini, and D Del Monte, and V Catena, and I Attar, and M Cesaro, and D Soranzo, and G Rattazzi, and G L Alati
June 1996, Acta anaesthesiologica Sinica,
Copied contents to your clipboard!