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Pulse Pressure Variation (pulse + pressure_variation)
Selected AbstractsPulse pressure variation and stroke volume variation during different loading conditions in a paediatric animal modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2008J. RENNER Background: Previous studies in adult patients and animal models have demonstrated that pulse pressure variation (PPV) and stroke volume variation (SVV) can be used to predict the response to fluid administration. Currently, little information is available on the performance of these variables in infants and neonates. The aim of our study was to assess whether PPV and SVV can predict fluid responsiveness in an animal model and to investigate the influence of different tidal volumes applied. Methods: PPV and SVV were monitored by pulse contour analysis in 19 anaesthetized and paralysed piglets during ventilation with tidal volumes (VT) of 5, 10 and 15 ml/kg both before and after fluid loading with 25 ml/kg of hydroxy-ethyl starch 6% (HES). Cardiac output was measured by pulmonary artery thermodilution and a positive response to HES infusion was defined as ,20% increase in the stroke volume index (SVI). Results: Before HES infusion, PPV and SVV were significantly greater during ventilation with a VT of 10 and 15 ml/kg than during ventilation with a VT of 5 ml/kg (P<0.05). After HES infusion, only ventilation with VT 15 ml/kg resulted in a significant increase in PPV and SVV. As assessed by receiver operating characteristic curve analysis, SVV during ventilation with VT 10 ml/kg was the best predictor of a positive response to fluid loading (AUC=0.87). Conclusions: In this paediatric animal model, we found that SVV during ventilation with 10 ml/kg was a sensitive and specific predictor of the response to fluid loading. [source] Automated pre-ejection period variation predicts fluid responsiveness in low tidal volume ventilated pigsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010S. T. VISTISEN Introduction: The respiratory variation in the pre-ejection period (,PEP) has been used to predict fluid responsiveness in mechanically ventilated patients. Recently, we automated this parameter and indexed it to tidal volume (PEPV) and showed that it was a reliable predictor for post-cardiac surgery, mainly paced, patients ventilated with low tidal volumes. The aims of the present animal study were to investigate PEPV's ability to predict fluid responsiveness under different fluid loading conditions and natural heart rates during low tidal volume ventilation (6 ml/kg) and to compare the performance of PEPV with other markers of fluid responsiveness. Methods: Eight prone, anesthetized piglets (23,27 kg) ventilated with tidal volumes of 6 ml/kg were subjected to a sequence of 25% hypovolemia, normovolemia, and 25% and 50% hypervolemia. PEPV, ,PEP, pulse pressure variation (PPV), central venous pressure (CVP), and pulmonary artery occlusion pressure (PAOP) were measured before each volume expansion. Results: Sensitivity was 89% and specificity was 93% for PEPV, 78% and 93% for ,PEP, 89% and 100% for PPV, 78% and 93% for CVP, and 89% and 87% for PAOP. Conclusion: PEPV predicts fluid responsiveness in low tidal volume ventilated piglets. [source] Automated pre-ejection period variation indexed to tidal volume predicts fluid responsiveness after cardiac surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2009S. T. VISTISEN Background: Reliable continuous monitoring of fluid responsiveness is an unsolved issue in patients ventilated with low tidal volume. We hypothesised that variations in the pre-ejection period (PEP) defined as the time interval between electrocardiogram (ECG) R-wave and onset of systolic upstroke in arterial blood pressure could reliably predict fluid responsiveness in patients ventilated with moderately low tidal volume. Furthermore, we hypothesised that indexing dynamic parameters to tidal volume would improve their prediction. The aim was to refine and automate a previously suggested algorithm for PEP variation (,PEP) and to test this new parameter indexed to tidal volume (PEPV), as a marker of fluid responsiveness along with central venous pressure (CVP), pulse pressure variation (PPV) and ,PEP. Additionally, the aim was to evaluate the concept of indexing dynamic parameters to tidal volume. Methods: Arterial pressure, CVP, ECG and cardiac index (CI) were acquired from 23 mechanically ventilated post-cardiac surgery patients scheduled for volume expansion. PEPV, PPV and ,PEP were extracted. Results: Using responder/non-responder classification (response=change in CI>+15%), sensitivity and specificity were 100% and 83%, respectively, for PEPV, 94% and 83% for ,PEP, and 94% and 83% for PPV. CVP offered no relevant information. Tidal volume indexing improved sensitivity for ,PEP to 100%. Conclusion: In this study in post-cardiac surgery patients, a refined parameter, PEPV, predicted fluid responsiveness better than PPV and ,PEP. Our results suggest that dynamic parameters using variations in PEP should be indexed to tidal volume. [source] Fluid therapy in acute myocardial infarction: evaluation of predictors of volume responsivenessACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009J. SNYGG Background: Static vascular filling pressures suffer from poor predictive power in identifying the volume-responsive heart. The use of dynamic arterial pressure variables, including pulse pressure variation (PPV) has instead been suggested to guide volume therapy. The aim of the present study was to evaluate the performance of several clinically applicable haemodynamic parameters to predict volume responsiveness in a pig closed chest model of acute left ventricular myocardial infarction. Methods: Fifteen anaesthetized, mechanically ventilated pigs were studied following acute left myocardial infarction by temporary coronary occlusion. Animals were instrumented to monitor central venous (CVP) and pulmonary artery occlusion (PAOP) pressures and arterial systolic variations (SPV) and PPV. Cardiac output (CO) was measured using the pulmonary artery catheter and by using the PiCCOŽ monitor also giving stroke volume variation (SVV). Variations in the velocity time integral by pulsed-wave Doppler echocardiography were determined in the left (,VTILV) and right (,VTIRV) ventricular outflow tracts. Consecutive boluses of 4 ml/kg hydroxyethyl starch were administered and volume responsiveness was defined as a 10% increase in CO. Results: Receiver,operator characteristics (ROC) demonstrated the largest area under the curve for ,VTIRV [0.81 (0.70,0.93)] followed by PPV [0.76 (0.64,0.88)] [mean (and 95% CI)]. SPV, ,VTILV and SVV did not change significantly during volume loading. CVP and PAOP increased but did not demonstrate significant ROC. Conclusion: PPV may be used to predict the response to volume administration in the setting of acute left ventricular myocardial infarction. [source] Pulse pressure variation and stroke volume variation during different loading conditions in a paediatric animal modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2008J. RENNER Background: Previous studies in adult patients and animal models have demonstrated that pulse pressure variation (PPV) and stroke volume variation (SVV) can be used to predict the response to fluid administration. Currently, little information is available on the performance of these variables in infants and neonates. The aim of our study was to assess whether PPV and SVV can predict fluid responsiveness in an animal model and to investigate the influence of different tidal volumes applied. Methods: PPV and SVV were monitored by pulse contour analysis in 19 anaesthetized and paralysed piglets during ventilation with tidal volumes (VT) of 5, 10 and 15 ml/kg both before and after fluid loading with 25 ml/kg of hydroxy-ethyl starch 6% (HES). Cardiac output was measured by pulmonary artery thermodilution and a positive response to HES infusion was defined as ,20% increase in the stroke volume index (SVI). Results: Before HES infusion, PPV and SVV were significantly greater during ventilation with a VT of 10 and 15 ml/kg than during ventilation with a VT of 5 ml/kg (P<0.05). After HES infusion, only ventilation with VT 15 ml/kg resulted in a significant increase in PPV and SVV. As assessed by receiver operating characteristic curve analysis, SVV during ventilation with VT 10 ml/kg was the best predictor of a positive response to fluid loading (AUC=0.87). Conclusions: In this paediatric animal model, we found that SVV during ventilation with 10 ml/kg was a sensitive and specific predictor of the response to fluid loading. [source] The value of pulse pressure and stroke volume variation as predictors of fluid responsiveness during open chest surgeryANAESTHESIA, Issue 7 2010P. A. H. Wyffels Summary We investigated the ability of pulse pressure variation and stroke volume variation to predict fluid responsiveness during mechanical ventilation in patients undergoing open chest surgery by comparing their respective correlations with cardiac output changes induced by leg elevation. Serial leg elevation manoeuvres were performed before and after sternotomy in 15 patients scheduled for elective off-pump coronary bypass surgery. Under closed chest conditions, both pulse pressure variation and stroke volume variation correlated well with the induced cardiac output changes (r = 0.856, p = 0.002 and r = 0.897, p = 0.0012, respectively). These correlations were lost for both parameters following sternotomy. Our data show that pulse pressure variation and stroke volume variation are valid predictors of fluid responsiveness under closed chest conditions but that this property no longer holds when the chest is open. [source] | ||||||||||