Dynamic Variables Of Fluid Responsiveness Research Articles

Effect of pneumoperitoneum on dynamic variables of fluid responsiveness (Delta PP and PVI) during Trendelenburg position.

Background and Aims:Pulse pressure variation (ΔPP) is considered as one of the best predictors of fluid responsiveness in patients under mechanical ventilation. Pleth Variability Index (PVI) has been proposed as a noninvasive alternative. However, pneumoperitoneum has been recently suggested as a limitation to their interpretation. The aim of this study was to compare changes in ΔPP and PVI related to autotransfusion associated with a Trendelenburg maneuver before and during pneumoperitoneum.Methods:50 patients undergoing elective abdominal laparoscopic surgery were enrolled in this prospective observational study. All patients were equipped with an invasive radial artery catheter and a PVI probe. After obtaining a stable signal with both ΔPP and PVI, baseline values were recorded, before and after head-down tilts of 10°, with or without abdominal insufflation (10-12 mmHg). All measurements were made before any fluid challenge under standardized anaesthesia, while patients were paralyzed and mechanically ventilated with 8 mL/kg tidal volume.Results:Changes in ΔPP and PVI associated with the Trendelenburg maneuver before and after insufflation of the pneumoperitoneum were significantly different (P < 0.001). In baseline conditions, the Trendelenburg maneuver was associated with a significant decrease in heart rate while mean arterial pressure remained unchanged. Both ΔPP and PVI decreased. After insufflation of the pneumoperitoneum, the Trendelenburg maneuver was associated with a significant decrease in heart rate and ΔPP and an increase in mean arterial pressure while PVI remained unchanged.Conclusion:Pneumoperitoneum did not alter the response of ΔPP to autotransfusion associated with the Trendelenburg maneuver, which was not the case for the PVI. This latter decreased during Trendelenburg maneuver performed alone and remained unchanged during Trendelenburg maneuver performed after insufflation of the pneumoperitoneum.

Assessments of Dynamic Variables of Fluid Responsiveness to Predict Desufflation-induced Hypotension in Urologic Patients Undergoing Laparoscopic Surgery

Assessments of Dynamic Variables of Fluid Responsiveness to Predict Desufflation-induced Hypotension in Urologic Patients Undergoing Laparoscopic Surgery

Fluid resuscitation during early sepsis: a need for individualization.

The prognosis of septic shock is tightly linked to the earliness of both appropriate antibiotic therapy and early hemodynamic resuscitation. This latter is essentially based on fluid and vasopressors administration. The step-by-step strategy, called "early goal-directed therapy" (EGDT) developed in 2001 and endorsed by the Surviving Sepsis Campaign (SSC) between 2004 and 2016 is no longer recommended. Indeed, recent multicenter randomized clinical trials showed no reduction in all-cause mortality, duration of organ support and in-hospital length of stay with EGDT in comparison with standard care. The most recent SCC guidelines have dropped the original EGDT by deleting the central venous pressure and the central venous oxygen saturation from the recommendations. Dynamic variables of fluid responsiveness are now recommended to be used after an initial fluid infusion of a fixed volume (30 mL/kg) during the first three hours of resuscitation. However, this approach is also questionable due to the lack of individualization at the early and crucial phase of resuscitation. In this review, we propose a more personalized approach for the early and later phases of fluid resuscitation during sepsis.

Assessment of dynamic variables of fluid responsiveness to predict desufflation-induced hypotension during paediatric laparoscopic surgery

BackgroundDuring laparoscopic surgery in paediatric patients, sudden hypotension may occur following peritoneal desufflation due to hypovolaemia or an acute increase in gastrointestinal venous capacitance by the release of intra-abdominal pressure. This study examined whether dynamic variables of fluid responsiveness during pneumoperitoneum can predict the occurrence of hypotension following desufflation. MethodsA total of 120 paediatric subjects were prospectively enrolled. A predictor was derived from the initial 83 subjects and validated thereafter in 37 high-risk subjects. The pleth variability index, respiratory variation in the pulse oximetry plethysmographic waveform (ΔPOP), systolic pressure variation and pulse pressure variation during pneumoperitoneum were obtained 1 min before desufflation. Predictors of desufflation-induced hypotension were investigated using the multivariable logistic regression analysis. Predictability was assessed using the area under the receiver-operating characteristic curve (AUC). ResultsIn the derivation cohort, 27% (n=23) of subjects developed hypotension. Only ΔPOP was found to be a predictor, and showed high predictability of desufflation-induced hypotension [AUC 0.87, P<0.0001, 95% confidence interval (CI): 0.78–0.93]. A ΔPOP cut-off point of 38% predicted hypotension with a sensitivity of 83% and a specificity of 90%. In the validation cohort, 43% (n=16) of subjects developed hypotension, and ΔPOP was verified to be highly predictive of the occurrence of hypotension (AUC 0.90, P<0.0001, 95% CI: 0.76–0.98). The sensitivity and specificity of a ΔPOP cut-off point of 38% to predict hypotension was 88% and 90%, respectively. ConclusionsThe ΔPOP during pneumoperitoneum is useful in predicting desufflation-induced hypotension during paediatric laparoscopic surgery. Clinical trial registrationNCT02536521.

The increase of vasomotor tone avoids the ability of the dynamic preload indicators to estimate fluid responsiveness

BackgroundThe use of vasoconstrictor can affect the dynamic indices to predict fluid responsiveness. We investigate the effects of an increase of vascular tone on dynamic variables of fluid responsiveness in a rabbit model of hemorrhage, and to examine the ability of the arterial pressure surrogates dynamic indices to track systolic volume variation (SVV) during hypovolemia under increased vasomotor tone.MethodsEighteen anesthetized and mechanically ventilated rabbits were studied during normovolemia (BL) and after blood progressive removal (15 mL/kg, BW). Other two sets of data were obtained during PHE infusion with normovolemia (BL + PHE) and during hypovolemia (BW + PHE). We measured central venous and left ventricular (LV) pressures and infra diaphragmatic aortic blood flow (AoF) and pressure. Pulse pressure variation (PPV), systolic pressure variation (SPV) and SVV were estimated manually by the variation of beat-to-beat PP, SP and SV, respectively. We also calculated PPVapnea as 100 × (PPmax-PPmin)/PP during apnea. The vasomotor tone was estimated by total peripheral resistance (TPR = mean aortic pressure/mean AoF), dynamic arterial elastance (Eadyn = PPV/SVV) and arterial compliance (C = SV/PP). We assessed LV preload by LV end-diastolic pressure (LVEDP). We compared the trending abilities between SVV and pressure surrogate indices using four-quadrant plots and polar plots.ResultsBaseline PPV, SPV, PPVapnea, and SVV increased significantly during hemorrhage, with a decrease of AoF (P < 0.05). PHE induced significant TPR and Eadyn increase and C decrease in bled animals, and a further decrease in AoF with a significant decrease of all dynamic indices. There was a significant correlation between SVV and PPV, PPVapnea and SPV in normal vasomotor tone (r2 ≥ 0.5). The concordance rate was 91%, 95% and 76% between SVV and PPV, PPVapnea and SPV, respectively, in accordance with the polar plot analysis. During PHE infusion, there was no correlation between SVV and its surrogates, and both four-quadrant plot and polar plot showed poor trending.ConclusionIn this animal model of hemorrhage and increased vasomotor tone induced by phenylephrine the ability of dynamic indices to predict fluid responsiveness seems to be impaired, masking the true fluid loss. Moreover, the arterial pressure surrogates have not the reliable trending ability against SVV.

Accuracy of volumetric and dynamic variables of fluid responsiveness in presence of left ventricular hypertrophy and diastolic dysfunction

Broch, O.; Renner, J.; Gruenewald, M.; Carstens, A.; Steinfath, M.; Bein, B. Author Information

Perioperatives Flüssigkeitsmanagement - Abschätzung des Volumenstatus

Cardiac filling pressures alone are not appropriate to estimate the effect of a volume challenge on the corresponding change in stroke volume. Dynamic variables of fluid responsiveness have been shown to discriminate with acceptable sensitivity and specificity between responders and non-responders to a volume challenge. However, several clinical confounders have been indentified which potentially influence the predictive power of these variables. Sound knowledge of these confounders and the acknowledgement that there is no unique threshold value for volume optimisation but a considerable "gray zone" is necessary to fully exploit the advantages of functional haemodynamic monitoring.

Dynamic variables of fluid responsiveness during pneumoperitoneum and laparoscopic surgery

Few data exist on dynamic variables predicting fluid responsiveness during laparoscopic surgery. The aim of this study was to explore the effects of laparoscopy on four dynamic variables: respiratory variations in pulse pressure (ΔPP), stroke volume variation by Vigileo/FloTrac (SVV (Vigileo) ), pleth variability index (PVI) and respiratory variations in pulse oximetry plethysmography waveform amplitude (ΔPOP), and their relation to fluid challenges during laparoscopic surgery. ΔPP, SVV (Vigileo) , PVI and ΔPOP were studied in 20 adult patients before and during pneumoperitoneum (10-12 mmHg). During ongoing laparoscopic surgery, relations between the dynamic variables and changes in stroke volume oesophageal Doppler, (SV(OD) ) after fluid challenges (250 ml colloid) were evaluated. Pneumoperitoneum changed the dynamic variables as follows {mean [95% confidence interval (CI)]}: ΔPP 0.5 (-1.3, 2.3)%, P = 0.53; SVV (Vigileo) 0.6 (-1.3, 2.5)%, P = 0.52; PVI 2.9 (0.4, 5.3)%, P = 0.025. For ΔPOP, median difference (95% CI) was 2.5 (-0.15, 6.7)%, P = 0.058. During laparoscopic surgery, areas under receiver operating characteristics curves (95% CI) were ΔPP 0.53 (0.31-0.75), SVV (Vigileo) 0.74 (0.51-0.90), PVI 0.61 (0.38-0.81), ΔPOP 0.63 (0.40-0.82). Correlation coefficients (P-values) between changes in dynamic variables and changes in SV(OD) were ΔPP r = -0.65, P = 0.009; SVV (Vigileo) r = -0.73, P = 0.002; PVI r = -0.22, P = 0.44; ΔPOP r = -0.32, P = 0.24. ΔPP and SVV (Vigileo) did not change as pneumoperitoneum was established, whereas PVI increased and ΔPOP tended to increase. All four dynamic variables predicted fluid responsiveness relatively poor during ongoing laparoscopic surgery. ΔPP and SVV (Vigileo) tracked changes in stroke volume induced by fluid challenges during ongoing laparascopic surgery, whereas ΔPOP and PVI did not.

Assessment of Fluid Responsiveness

Assessment of Fluid Responsiveness

Assessment of fluid responsiveness during increased intra-abdominal pressure: keep the indices, but change the thresholds

Dynamic variables of fluid responsiveness are useful guides for fluid management in patients under controlled positive pressure ventilation. In the previous issue of Critical Care, Jacques and colleagues show that these variables remain reliable predictors of fluid responsiveness in a porcine model of intra-abdominal hypertension, but threshold values are higher than during normal intra-abdominal pressure. Their threshold values, however, cannot be applied to clinical practice. This study suggests that intra-abdominal pressure must be measured in critically ill patients, and 'supranormal' values of dynamic variables should be analyzed with caution. The 'fluid responsive part' of an increased dynamic variable in such patients may be estimated by measuring its change during a fluid challenge.

Effects of norepinephrine on dynamic variables of fluid responsiveness during hemorrhage and after resuscitation in a pediatric porcine model

The effect of vasopressors on pulse pressure variation (PPV), stroke volume variation (SVV) and on the volumetric variable global end-diastolic volume (GEDV) during changing loading conditions is currently under debate. The aim of our study was to investigate the effect of norepinephrine (NE) on PPV, SVV and GEDV in a pediatric animal model of hemorrhage and resuscitation. Eight anesthetized piglets were studied at normovolemia, after stepwise blood withdrawal (25 ml x kg(-1)), after infusion of NE to restore mean arterial pressure (MAP), after NE titration was stopped and shed blood was retransfused and finally again after NE titration. Stroke volume (SV) was measured using a thermodilution pulmonary artery catheter. GEDV was measured by transpulmonary thermodilution. PPV and SVV were monitored continuously by pulse contour analysis. In response to NE administration during hemorrhage, MAP significantly increased (P < 0.01), PPV significantly decreased (P = 0.02), whereas SVV, SV and GEDV remained unchanged. After retransfusion, SVV and GEDV significantly correlated with volume induced percentage change in SV. This significant correlation was reversed after NE administration for SVV and persisted for GEDV. In conclusion, NE administration significantly affected PPV and SVV, whereas the volumetric variable GEDV remained unchanged.

Effect of elevated PEEP on dynamic variables of fluid responsiveness in a pediatric animal model

Previous studies have demonstrated that stroke volume variation (SVV), pulse pressure variation (PPV) and global end-diastolic volume (GEDV) can be used to predict the response to fluid administration. Currently, little information is available whether application of different levels of positive end-expiratory pressure (PEEP), especially in infants and neonates, affects their ability to predict fluid responsiveness. The aim of our study was to assess the effect of increasing PEEP levels on the predictive value of SVV, PPV and GEDV with respect to fluid responsiveness. Stroke volume variation and PPV were monitored continously in 22 anesthetized piglets during changing PEEP levels (5 and 10 cmH(2)O) both before and after fluid loading (FL). GEDV was measured by transpulmonary thermodilution; cardiac output and stroke volume (SV) were measured by pulmonary artery thermodilution. A positive response to FL was defined as > or =15% increase in SV. Fluid loading induced significant changes in all hemodynamic variables except of heart rate and systemic vascular resistance. At PEEP 5 cmH(2)O, SVV, PPV and GEDV significantly correlated with volume induced percentage change in SV, whereas at PEEP 10 cmH(2)O, this correlation was abolished for PPV. As assessed by receiver operating characteristic curve analysis, SVV and GEDV, independent of PEEP level applied, were the best predictors of a positive response to FL [area under the curve: SVV = 0.88; GEDV = 0.80]. In this pediatric animal model, SVV and GEDV were sensitive and specific predictors of fluid responsiveness during increasing PEEP levels.

Dynamic Variables of Fluid Responsiveness may be Related to the Type of Volume Challenge Performed

Dynamic Variables of Fluid Responsiveness may be Related to the Type of Volume Challenge Performed

Dynamic Variables of Fluid Responsiveness may be Related to the Type of Volume Challenge Performed

Dynamic Variables of Fluid Responsiveness may be Related to the Type of Volume Challenge Performed

The Influence of Tidal Volume on the Dynamic Variables of Fluid Responsiveness in Critically Ill Patients

Survey of Anesthesiology: February 2007 - Volume 51 - Issue 1 - p 9 doi: 10.1097/01.sa.0000255107.32117.44

The Influence of Tidal Volume on the Dynamic Variables of Fluid Responsiveness in Critically Ill Patients

Respiratory-related variabilities in stroke volume and arterial pulse pressure (Delta%Pp) are proposed to predict fluid responsiveness. We investigated the influence of tidal volume (Vt) and adrenergic tone on these variables in mechanically ventilated patients. Cyclic changes in aortic velocity-time integrals (Delta%VTI(Ao), echocardiography) and Delta%Pp (catheter) were measured simultaneously before and after intravascular volume expansion, and Vt was randomly varied below and above its basal value. Intravascular volume expansion was performed by hydroxyethyl starch (100 mL, 60 s). Receiver operating characteristic curves were generated for Delta%VTI(Ao), Delta%Pp and left ventricle cross-sectional end-diastolic area (echocardiography), considering the change in stroke volume after intravascular volume expansion (> or =15%) as the response criterion. Covariance analysis was used to test the influence of Vt on Delta%VTI(Ao) and Delta%Pp. Twenty-one patients were prospectively included; 9 patients (43%) were responders to intravascular volume expansion. Delta%VTI(Ao) and Delta%Pp were higher in responders compared with nonresponders. Predictive values of Delta%VTI(Ao) and Delta%Pp were similar (threshold: 20.4% and 10.0%, respectively) and higher than that of left ventricle cross-sectional end-diastolic area at the appropriate level of Vt. Delta%Pp was slightly correlated with norepinephrine dosage. Delta%Pp increased with the increase in the level of Vt both before and after intravascular volume expansion, contrasting with an unexpected stability of Delta%VTI(Ao). In conclusion, Delta%VTI(Ao) and Delta%Pp are good predictors of intravascular fluid responsiveness but the divergent evolution of these two variables when Vt was increased needs further explanation.