A technique for measurement of cardiac output by thermodilution (COTD) in man has been described. Comparison with cardiac outputs determined simultaneously by the dye-dilution technique (CODYE) in 63 measurements in 20 patients showed close agreement of the 2 methods in a range of values from 2.9 to 8.0 liters/min (COTD = 0.96 CODYE + 0.2, r = 0.96). The reproducibility of measurements was 4.1 percent with the thermodilution and 5.4 percent with the dye-dilution technique. The thermodilution technique does not require withdrawal of blood during measurements and removal of blood for calibration. The calibration is simple and accurate. There is virtually no recirculation, so that a simple integrator can be used for determination of the area beneath the thermodilution curve.

A new technique for measurement of cardiac output by thermodilution in man

Background Finger cuff technologies allow continuous noninvasive arterial blood pressure (AP) and cardiac output/index (CO/CI) monitoring. Methods We performed a meta-analysis of studies comparing finger cuff-derived AP and CO/CI measurements with invasive measurements in surgical or critically ill patients. We calculated overall random effects model-derived pooled estimates of the mean of the differences and of the percentage error (PE; CO/CI studies) with 95%-confidence intervals (95%-CI), pooled 95%-limits of agreement (95%-LOA), Cochran's Q and I2 (for heterogeneity). Results The pooled mean of the differences (95%-CI) was 4.2 (2.8 to 5.62) mm Hg with pooled 95%-LOA of –14.0 to 22.5 mm Hg for mean AP (Q=230.4 [P Conclusions Study heterogeneity was high. Several studies showed interchangeability between AP and CO/CI measurements using finger cuff technologies and reference methods. However, the pooled results of this meta-analysis indicate that AP and CO/CI measurements using finger cuff technologies and reference methods are not interchangeable in surgical or critically ill patients. Clinical trial number PROSPERO registration number: CRD42019119266.

Continuous noninvasive pulse wave analysis using finger cuff technologies for arterial blood pressure and cardiac output monitoring in perioperative and intensive care medicine: a systematic review and meta-analysis

Purpose of reviewTo review the different methods available for the assessment of cardiac output (CO) and describe their specific indications in intensive care and perioperative medicine.Recent findingsIn critically ill patients, persistent circulatory shock after initial resuscitation is an indicati

Cardiac output monitoring: how to choose the optimal method for the individual patient.

Submitted for publication June 12, 2020. Accepted for publication October 5, 2020. Published online first on November 18, 2020. From the Department of Anesthesiology, Center of Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany (B.S.); Outcomes Research Consortium, Cleveland, Ohio (B.S.); and Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio (D.I.S.).

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Perioperative Blood Pressure Management.

Pulse wave analysis enables cardiac output to be estimated continuously and in real time. Pulse wave analysis methods can be classified into invasive, minimally invasive, and noninvasive and into externally calibrated, internally calibrated, and uncalibrated methods.

Pulse Wave Analysis to Estimate Cardiac Output.

The CNAP technology (CNSystems Medizintechnik AG, Graz, Austria) allows continuous noninvasive arterial pressure waveform recording based on the volume clamp method and estimation of cardiac output (CO) by pulse contour analysis We compared CNAP-derived CO measurements (CNCO) with intermittent invasive CO measurements (pulmonary artery catheter; PAC-CO) in postoperative cardiothoracic surgery patients In 51 intensive care unit patients after cardiothoracic surgery, we measured PAC-CO (criterion standard) and CNCO at three different time points We conducted two separate comparative analyses: (1) CNCO auto-calibrated to biometric patient data (CNCObio) versus PAC-CO and (2) CNCO calibrated to the first simultaneously measured PAC-CO value (CNCOcal) versus PAC-CO The agreement between the two methods was statistically assessed by Bland-Altman analysis and the percentage error In a subgroup of patients, a passive leg raising maneuver was performed for clinical indications and we present the changes in PAC-CO and CNCO in four-quadrant plots (exclusion zone 05 L/min) in order to evaluate the trending ability of CNCO The mean difference between CNCObio and PAC-CO was +05 L/min (standard deviation ± 13 L/min; 95% limits of agreement -19 to +30 L/min) The percentage error was 49% The concordance rate was 100% For CNCOcal, the mean difference was -03 L/min (±05 L/min; -12 to +07 L/min) with a percentage error of 19% In this clinical study in cardiothoracic surgery patients, CNCOcal showed good agreement when compared with PAC-CO For CNCObio, we observed a higher percentage error and good trending ability (concordance rate 100%)

A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients.

Annmarie Körner

Papers

Continuous noninvasive pulse wave analysis using finger cuff technologies for arterial blood pressure and cardiac output monitoring in perioperative and intensive care medicine: a systematic review and meta-analysis

A comparison of volume clamp method-based continuous noninvasive cardiac output (CNCO) measurement versus intermittent pulmonary artery thermodilution in postoperative cardiothoracic surgery patients.