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Updated: May 9, 2026
Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge
Published on: January 20, 2023
Hemodynamic pressure waveform analysis in predicting fluid responsiveness
Sébastien Roy1, Pierre Couture, Baqir Qizilbash
1Department of Anesthesiology, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
Objective:
To assess the usefulness of central venous pressure (CVP), diastolic right ventricular pressure, and pulmonary capillary wedge pressure (PCWP) waveform analysis in predicting fluid responsiveness.
Design:
A prospective observational study.
Setting:
Tertiary care university hospital.
Patients:
Forty-four patients undergoing coronary artery bypass grafting.
Interventions:
Analysis of the a/v wave ratio of the PCWP, CVP, and right ventricular dP/dt to predict an increase in stroke volume >15% after the administration of 500 mL of colloid.
Measurements And Main Results:
Forty-four patients were enrolled in this study and 7 were excluded. There were 24 responders and 13 nonresponders. No differences in mean CVP and PCWP values between the responders and the nonresponders were found. The only parameter associated with a significant response to volume infusion was the ratio of the a/v waves of the PCWP tracing (p = 0.0001). The performance of the a/v wave ratio>1 of the PCWP tracing in predicting fluid responsiveness was evaluated by constructing a receiver operating characteristic curve. The area under the receiver operating characteristic curve was 0.89 (95% confidence interval, 0.79-0.99; p<0.05).
Conclusions:
The a/v ratio measured on the PCWP tracing is a predictor of fluid responsiveness in patients with preserved left ventricular function undergoing coronary artery bypass grafting.
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