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Cardiac Response to β-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis
Published on: May 19, 2021
Evaluation of stroke volume variations obtained with the pressure recording analytic method
Matthieu Biais1, Vincent Cottenceau, Laurent Stecken
1Emergency Department, Centre Hospitalier Universitaire de Bordeaux, France. matthieu.biais@chu-bordeaux.fr
Critical Care Medicine
|March 20, 2012
Summary
Stroke volume variations from the pressure recording analytic method do not reliably predict fluid responsiveness in mechanically ventilated patients. Pulse pressure variations are a better indicator of fluid responsiveness in these critically ill patients.
Area of Science:
- Critical Care Medicine
- Cardiovascular Physiology
- Mechanical Ventilation
Background:
- Fluid responsiveness assessment is crucial in mechanically ventilated patients with circulatory failure.
- Accurate prediction of fluid responsiveness guides fluid therapy and improves patient outcomes.
- Current methods for assessing fluid responsiveness have limitations.
Purpose of the Study:
- To evaluate the efficacy of stroke volume variations (SVV) derived from the pressure recording analytic method (PRAM) in predicting fluid responsiveness.
- To compare the predictive value of SVV with pulse pressure variations (PPV) and echocardiography-derived cardiac output.
- To determine if PRAM can accurately track changes in cardiac output after fluid administration.
Main Methods:
- Prospective study conducted in a surgical intensive care unit.
- Included 35 mechanically ventilated patients with circulatory failure undergoing fluid challenges.
- Measured SVV, PPV, and cardiac output (using PRAM and echocardiography) before and after a 500 mL saline fluid challenge.
Main Results:
- Nineteen patients (54%) were responders, defined by a ≥15% increase in echocardiography-derived stroke volume.
- Baseline SVV did not differ between responders and non-responders (10% vs. 14%).
- Pulse pressure variations were significantly higher in responders (17% vs. 7%; p < .0001) and demonstrated high sensitivity (89%) and specificity (88%) at a 10% threshold.
- PRAM-derived cardiac output changes did not correlate with echocardiography-derived changes (r = 0.14; p > .05).
Conclusions:
- Stroke volume variations obtained with the pressure recording analytic method are not reliable predictors of fluid responsiveness in mechanically ventilated ICU patients.
- Pulse pressure variations are a more effective predictor of fluid responsiveness in this population.
- The pressure recording analytic method is inadequate for tracking cardiac output changes induced by volume expansion.
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