Relative value of pressures and volumes in assessing fluid responsiveness after valvular and coronary artery surgery

Abstract

While volumes are equally useful in monitoring fluid responsiveness, the predictive and monitoring value of PAOP is greater after VS than after CAS. In contrast, the CVP is of similar value as volume measurements in monitoring fluid responsiveness after CAS. The different value of pressures rather than of volumes between surgery types is likely caused by systolic left ventricular dysfunction in VS. The study suggests an effect of systolic cardiac function on optimal parameters of fluid responsiveness and superiority of the pulmonary artery catheter over transpulmonary dilution, for haemodynamic monitoring of VS patients.

Cardiac filling volumes versus pressures for predicting fluid responsiveness after cardiovascular surgery: the role of systolic cardiac function

“…Nevertheless, the trend was for the increasing value of pressure monitoring in patients with low versus those with normal GEF in the study by Reuter et al [14]. The current data also agree with our previous study in a cohort of valvular and coronary artery surgery patients [21], showing the superior value of the pulmonary artery catheter-derived pressures over transpulmonary dilution-derived volumes for assessing fluid responsiveness in the former with a low GEF and presumed left ventricular systolic dysfunction. The current study thus suggests that systolic cardiac function and the degree of cardiac dilatation, rather than underlying disease (type of surgery), determines the relative value of pressures and volumes for predicting and monitoring fluid responsiveness, as suggested previously [5].…”

“…Mundigler et al suggested that pressures were superior to transpulmonary thermodilution-derived volumes for monitoring changes in cardiac preload during fluid loading in non-surgical patients with left ventricular systolic dysfunction, measured by transesophageal echocardiography [20]. We also suggested this in patients with presumed left ventricular systolic dysfunction based on transpulmonary thermodilution-derived global ejection fraction (GEF) following valvular surgery [21]. However, others did not reach the same conclusion [14,17].…”

Choosing Patient-tailored Hemodynamic Monitoring

“…In contrast, a suspected ventricular septal defect may require monitoring with help of a PAC, echocardiography, or both. In mechanically ventilated patients, fi lling pressures that are confounded by airway pressures may be less useful in predicting and guiding fl uid responses than volumetric preload measure ments [34,36], whereas the currently proposed superiority of dynamic indices [33] can be questioned, as they are aff ected by ventilatory frequency and tidal volume. Finally, pulse-contour methods are sensitive to arrhythmias, aortic valve regurgitation, intra-aortic balloon pumping and peripheral vascular disease.…”

“…Th e presence of cardiac disease and mechanical ventilation may also aff ect choices. It is likely that a PAC and measurement of PAOP is more helpful in guiding (fl uid) management in the presence of systolic/diastolic cardiac dysfunction than during hypovolemic shock, for example [21,34]. In severe left-sided valvular disease, right-sided measurements of cardiac output are probably preferable to transpulmonary ones, even though the debate on the confounding eff ect of even minimal tricuspid regurgitation on these measurements has not yet ended.…”

“…Some hemodynamic optimization strategies, such as fl uid management guided by prediction of fl uid responses, early goal-directed therapy, and perioperative hemodynamic optimization or fl uid restriction, may help to improve patient outcomes, in terms of reducing complications, lengths of stay, and prevention of overhydration, for example, even irrespective of vital status [1,16,25,[28][29][30][31][32][33]. Devices and parameters to assess fl uid responsiveness include transpulmonary dilution-derived cardiac volumes, esophageal Doppler fl ow and echocardiographic indices, and dynamic indices provided by pulse-contour methods [10,11,24,25,33,34]. In contrast, central venous pressure (CVP) monitoring may suffi ce in successful fl uid restriction policies [32].…”