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Bernard Cholley - One of the best experts on this subject based on the ideXlab platform.

  • equipment review new techniques for cardiac output measurement oesophageal doppler Fick Principle using carbon dioxide and pulse contour analysis
    Critical Care, 2002
    Co-Authors: Christine Berton, Bernard Cholley
    Abstract:

    Measuring cardiac output is of paramount importance in the management of critically ill patients in the intensive care unit and of 'high risk' surgical patients in the operating room. Alternatives to thermodilution are now available and are gaining acceptance among practitioners who have been trained almost exclusively in the use of the pulmonary artery catheter. The present review focuses on the Principles, advantages and limitations of oesophageal Doppler, Fick Principle applied to carbon dioxide, and pulse contour analysis. No single method stands out or renders the others obsolete. By making cardiac output easily measurable, however, these techniques should all contribute to improvement in haemodynamic management.

  • noninvasive monitoring of cardiac output in critically ill patients using transesophageal doppler
    American Journal of Respiratory and Critical Care Medicine, 1998
    Co-Authors: Bruno Valtier, Bernard Cholley, Jeanpierre Belot, Jeanemmanuel De La Coussaye, Joaquim Mateo, Didier Payen
    Abstract:

    Measurement of cardiac output using thermodilution technique in mechanically ventilated patients is associated with significant morbidity. The goal of the present study was to assess the validity of cardiac output measurement using transesophageal Doppler in critically ill patients. Forty-six patients from three different intensive care units underwent 136 paired cardiac output measurements using thermodilution (COTH) and transesophageal Doppler (COTED). In addition, simultaneous suprasternal Doppler and indirect calorimetry (Fick Principle) were used to measure cardiac output in 26 patients from one center. A good correlation was found between COTH and COTED (r = 0.95), with a small systematic underestimation (bias = 0.24 L/min) using transesophageal Doppler. The limits of agreement between COTH and COTED were + 2 L/min and − 1.5 L/min. Variations in cardiac output between two consecutive measures using either transesophageal Doppler or thermodilution techniques were similar in direction and magnitude (b...

Elena K. Grant - One of the best experts on this subject based on the ideXlab platform.

  • cmr fluoroscopy right heart catheterization for cardiac output and pulmonary vascular resistance results in 102 patients
    Journal of Cardiovascular Magnetic Resonance, 2017
    Co-Authors: Toby Rogers, Kanishka Ratnayaka, Jaffar M. Khan, William H. Schenke, Laurie P. Grant, Jonathan R. Mazal, Elena K. Grant, Annette M Stine
    Abstract:

    Quantification of cardiac output and pulmonary vascular resistance (PVR) are critical components of invasive hemodynamic assessment, and can be measured concurrently with pressures using phase contrast CMR flow during real-time CMR guided cardiac catheterization. One hundred two consecutive patients underwent CMR fluoroscopy guided right heart catheterization (RHC) with simultaneous measurement of pressure, cardiac output and pulmonary vascular resistance using CMR flow and the Fick Principle for comparison. Procedural success, catheterization time and adverse events were prospectively collected. RHC was successfully completed in 97/102 (95.1%) patients without complication. Catheterization time was 20 ± 11 min. In patients with and without pulmonary hypertension, baseline mean pulmonary artery pressure was 39 ± 12 mmHg vs. 18 ± 4 mmHg (p < 0.001), right ventricular (RV) end diastolic volume was 104 ± 64 vs. 74 ± 24 (p = 0.02), and RV end-systolic volume was 49 ± 30 vs. 31 ± 13 (p = 0.004) respectively. 103 paired cardiac output and 99 paired PVR calculations across multiple conditions were analyzed. At baseline, the bias between cardiac output by CMR and Fick was 5.9% with limits of agreement −38.3% and 50.2% with r = 0.81 (p < 0.001). The bias between PVR by CMR and Fick was −0.02 WU.m2 with limits of agreement −2.6 and 2.5 WU.m2 with r = 0.98 (p < 0.001). Correlation coefficients were lower and limits of agreement wider during physiological provocation with inhaled 100% oxygen and 40 ppm nitric oxide. CMR fluoroscopy guided cardiac catheterization is safe, with acceptable procedure times and high procedural success rate. Cardiac output and PVR measurements using CMR flow correlated well with the Fick at baseline and are likely more accurate during physiological provocation with supplemental high-concentration inhaled oxygen. Clinicaltrials.gov NCT01287026 , registered January 25, 2011.

  • CMR fluoroscopy right heart catheterization for cardiac output and pulmonary vascular resistance: results in 102 patients
    'Springer Science and Business Media LLC', 2017
    Co-Authors: Toby Rogers, Kanishka Ratnayaka, Jaffar M. Khan, Annette Stine, William H. Schenke, Laurie P. Grant, Jonathan R. Mazal, Elena K. Grant, Adrienne Campbell-washburn, Michael S. Hansen
    Abstract:

    Abstract Background Quantification of cardiac output and pulmonary vascular resistance (PVR) are critical components of invasive hemodynamic assessment, and can be measured concurrently with pressures using phase contrast CMR flow during real-time CMR guided cardiac catheterization. Methods One hundred two consecutive patients underwent CMR fluoroscopy guided right heart catheterization (RHC) with simultaneous measurement of pressure, cardiac output and pulmonary vascular resistance using CMR flow and the Fick Principle for comparison. Procedural success, catheterization time and adverse events were prospectively collected. Results RHC was successfully completed in 97/102 (95.1%) patients without complication. Catheterization time was 20 ± 11 min. In patients with and without pulmonary hypertension, baseline mean pulmonary artery pressure was 39 ± 12 mmHg vs. 18 ± 4 mmHg (p 

David M Systrom - One of the best experts on this subject based on the ideXlab platform.

  • Fick Principle and exercise pulmonary hemodynamic determinants of the six minute walk distance in pulmonary hypertension
    Pulmonary circulation, 2020
    Co-Authors: Phillip Joseph, Aaron B Waxman, Rudolf K F Oliveira, Roza Badr Eslam, Manyoo Agarwal, David M Systrom
    Abstract:

    The six-minute walk test is widely used to assess the severity and prognosis of pulmonary hypertension. However, the pathophysiology underlying a compromised six-minute walk distance is incompletel...

  • impaired systemic oxygen extraction at maximum exercise in pulmonary hypertension
    Medicine and Science in Sports and Exercise, 2008
    Co-Authors: James J Tolle, Aaron B Waxman, David M Systrom
    Abstract:

    ABSTRACTPurpose:To determine the relative contributions of the Fick Principle variables to impaired exercise tolerance in pulmonary arterial hypertension compared with pulmonary venous hypertension.Methods:One hundred forty-seven consecutive, complete, clinically indicated cardiopulmonary exercise t

  • maximum cardiac output during incremental exercise by first pass radionuclide ventriculography
    Chest, 1998
    Co-Authors: Jaman Maroni, David A Oelberg, Paul P Pappagianopoulos, Charles A Boucher, David M Systrom
    Abstract:

    Study objective To validate a noninvasive first-pass radionuclide ventriculographic (FPRV) measurement of maximum cardiac output (Qv) during exercise. Design Comparison of Qv to that measured by the Fick Principle (Qf) at peak exercise. Setting Academic cardiopulmonary exercise laboratory. Patients Seventy-eight consecutive patients without a history of septal defect undergoing clinically indicated maximum incremental cardiopulmonary exercise testing with pulmonary arterial catheterization and FPRV. Measurements and results Ventilation and gas exchange were measured breath-by-breath or by a mixing chamber/mass spectrometer system. Arterial and mixed venous O 2 content were measured each minute during exercise. When patients without left-to-right ventricular stroke count ratio evidence for left-sided regurgitation were isolated, peak Qv was linearly related to Qf (r=0.75, p=0.0001). To account for a small systematic overestimation (bias) of Qf by Qv, the linear equation for the Qv/Qf relation was derived for patients studied between 1990 and 1993 and applied to those studied subsequently. The resulting corrected peak Qv was tightly related to peak Qf (r=0.90, p Conclusion FPRV can reasonably estimate maximum cardiac output during incremental exercise in patients for whom the technique has ruled out left-sided cardiac regurgitant lesions.

D Schranz - One of the best experts on this subject based on the ideXlab platform.

J Takala - One of the best experts on this subject based on the ideXlab platform.

  • estimation of splanchnic blood flow by the Fick Principle in man and problems in the use of indocyanine green
    Cardiovascular Research, 1995
    Co-Authors: Ari Uusaro, E Ruokonen, J Takala
    Abstract:

    Objectives: Measurement of splanchnic blood flow is necessary to evaluate the effect of therapeutic interventions on splanchnic tissue perfusion. Systemic indocyanine green (ICG) clearance has been used to estimate splanchnic blood flow, but the results may be compromised by altered hepatic dye extraction. We evaluated the applicability of simultaneous estimation of splanchnic and femoral blood flow by dye dilution and regional blood sampling in intensive care patients. Methods: 240 simultaneous determinations of regional blood flow were conducted in different patient groups (cardiac surgery, ARDS, pancreatitis, septic shock, preoperative controls). The measurement protocol consists of catheterizations of hepatic vein, femoral artery and vein and primed constant infusion of two different ICG preparations. Results: The method was used successfully in a wide variety of patients. Steady-state dye concentration and sufficient dye extraction was achieved in each group of patients. The coefficient of variation of splanchnic blood flow estimation was 7 ± 1% and of femoral blood flow estimation 6 ± 0%. There was a great intra- and interindividual variation of ICG extraction. Use of dobutamine modified the extraction in most patients but did not lessen the performance of the method. ICG extraction was markedly lower and the coefficient of variation of both femoral and splanchnic blood flow markedly higher with propylene glycol-dissolved ICG preparation as compared with the freeze-dried. Conclusions: The prerequisites for the method of primed, constant infusion of indocyanine green with hepatic vein catheterization are achieved in intensive care patients. The results of splanchnic blood flow estimations based on techniques with peripheral blood sampling should be interpreted with caution, and the use of ICG clearance as a flow-related indicator without the measurement of ICG extraction cannot be justified because of the great variability of dye extraction. Certain indocyanine green preparations may greatly modify the results of the regional blood flow determinations.