3 Physiology Background Oxygen delivery componentsCardiac output x oxygen saturation x hemoglobinCardiac output componentsStroke volumePreloadAfterload (Systemic Vascular Resistance)ContractilityHeart ratePrimary methods to increase cardiac outputIncrease preload (volume expanders)Increase contractility (inotropes)Decrease afterload (vasodilators)Key pointAdministering volume may increase intravascular volume and preload but not stroke volume and cardiac output
4 Frank-Starling Relationship Stroke VolumeIncreasing preload can have a significant or minimal impact on SV depending on where the patient is at in the Starling curvePreload
5 Fluid Administration Challenges Fluid administration is critical to optimizing oxygen delivery by optimizing cardiac output 1Unnecessary fluid administration may be harmful2Traditional methods to guide fluid administration often fail to predict fluid responsivenessAccurate only 50-60% of time 3Newer dynamic methods that can predict fluid responsiveness are invasive, complex, and/or costly 4Many patients are not candidates for this level of monitoring1 Perel A. Anesth Analg. 2008; 106 (4): Bundgaard-Nielsen M et al. Acta Anaesthesiol Scand. 2007; 51(3):331-403 Michard F et al. Chest. 2002; 121(6): Joshi G et al. Anesth Analg. 2005; 101:601-5
6 Pleth Variability Index (PVI) Masimo PVI is clinically proven to help clinicians assess fluid responsiveness and improve fluid management to reduce patient risk.1,2Once your Masimo Pulse CO-Oximeter is enabled with PVI-monitoring capability, PVI is automatically displayed for every patient receiving pulse oximetry monitoring1 Cannesson M et al. Br J Anaesth. 2008;101(2): Forget P et al. Anesth & Anal. 2010;111(4):910-4.
7 Pulse Pressure Variation and Changes in PPW During Ventilation Arterial Pulse Pressure VariationPPmax- PPmin(PPmax + PPmin) ÷ 2ΔPP =Pleth Waveform VariationPPWmax – PPWmin(PPWmax + PPWmin) ÷ 2ΔPPW =PPWmaxPPWminVentilatory CycleAdapted from: Cannesson M et al
8 PVI Calculation Automated measurement Changes in plethysmographic waveform amplitude over the respiratory cyclePVI is a percentage from 1 to 100%:1 - no pleth variability100 - maximum pleth variability
10 PVI to Help Clinicians Optimize Preload / Cardiac Output Stroke Volume10 %Lower PVI = Less likely to respondto fluid administration24 %Higher PVI = More likely to respond to fluid administrationPreloadMaxime Cannesson, MD, PhD
11 PVI to Help Clinicians Assess Fluid Responsiveness During Surgery: Similar to Arterial Pulse Pressure / Superior to CI, PCWP, CVPBackground. Respiratory variations in pulse oximetry plethysmographic waveform amplitude(DPOP) can predict fluid responsiveness in mechanically ventilated patients but cannot beeasily assessed at the bedside. Pleth variability index (PVI) is a new algorithm allowing for automatedand continuous monitoring of DPOP. We hypothesized that PVI can predict fluid responsivenessin mechanically ventilated patients under general anaesthesia.Methods. Twenty-five patients were studied after induction of general anaesthesia.Haemodynamic data [cardiac index (CI), respiratory variations in arterial pulse pressure (DPP),DPOP, and PVI] were recorded before and after volume expansion (500 ml of hetastarch 6%).Fluid responsiveness was defined as an increase in CI 15%.Results. Volume expansion induced changes in CI [2.0 (SD 0.9) to 2.5 (1.2) litre min21 m22;P,0.01], DPOP [15 (7)% to 8 (3)%; P,0.01], and PVI [14 (7)% to 9 (3)%; P,0.01]. DPOP andPVI were higher in responders than in non-responders [19 (9)% vs 9 (4)% and 18 (6)% vs 8(4)%, respectively; P,0.01 for both]. A PVI .14% before volume expansion discriminatedbetween responders and non-responders with 81% sensitivity and 100% specificity. There wasa significant relationship between PVI before volume expansion and change in CI after volumeexpansion (r¼0.67; P,0.01).Conclusions. PVI, an automatic and continuous monitor of DPOP, can predict fluid responsivenessnon-invasively in mechanically ventilated patients during general anaesthesia. Thisindex has potential clinical applications.Adapted from Cannesson M. et. al. Br J Anesth 2008;101(2):
12 PVI to Help Clinicians Assess Fluid Responsiveness During Surgery: Similar to Stroke Volume Variation / Superior to CVPBackground and objective Accurate assessment of a patient’svolume status is an important goal for an anaesthetist. However,most variables assessing fluid responsiveness are eitherinvasive or technically challenging. This study was designed tocompare the accuracy of arterial pressure-based stroke volumevariation (SVV) and variations in the pulse oximeterplethysmographic waveform amplitude as evaluated with thenoninvasive calculated pleth variability index (PVI) with centralvenous pressure to predict the response of stroke volume index(SVI) to volume replacement in patients undergoing majorsurgery.Methods We studied 20 patients scheduled for elective majorabdominal surgery. After induction of anaesthesia, allhaemodynamic variables were recorded immediately before (T1)and subsequent to volume replacement (T2) by infusion of 6%hydroxy-ethyl starch (HES) 130/0.4 (7 ml kg1) at a rate of1ml kg1 min1.Results The volume-induced increase in SVI was at least 15% in15 patients (responders) and less than 15% in five patients(nonresponders). Baseline SVV correlated significantly withchanges in SVI (DSVI; r¼0.80; P<0.001) as did baseline PVI(r¼0.61; P<0.004), whereas baseline values of central venouspressure showed no correlation to DSVI. There was nosignificant difference between the area under the receiveroperating characteristic curve for SVV (0.993) and PVI (0.973).The best threshold values to predict fluid responsiveness weremore than 11% for SVV and more than 9.5% for PVI.Conclusion Although arterial pressure-derived SVV revealedthe best correlation to volume-induced changes in SVI, theresults of our study suggest that both variables, SVV and PVI,can serve as valid indicators of fluid responsiveness inmechanically ventilated patients undergoing major surgery.Zimmermann M, et al. Eur J Anaesthesiol. 2010;27(66):
13 PVI to Assess Fluid Responsiveness in the ICU Similar to Pulse Pressure Variation / Superior to Cardiac OutputPPVPVICOObjective: To investigate whether the pleth variability index, anoninvasive and continuous tool, can predict fluid responsivenessin mechanically ventilated patients with circulatory insufficiency.Design: Prospective study.Setting: Surgical intensive care unit of a university hospital.Patients: Forty mechanically ventilated patients with circulatoryinsufficiency in whom volume expansion was planned byattending physician. Exclusion criteria included spontaneous respiratoryactivity, cardiac arrhythmia, known intracardiac shunt,severe hypoxemia (PaO2/FIO2 <100 mm Hg), contraindication forpassive leg raising, left ventricular ejection fraction of <50%, andhemodynamic instability during the procedure.Interventions: Fluid challenge with 500 mL of 130/0.4 hydroxyethyl-starch if respiratory variations in arterial pulse pressurewere >13% or with passive leg raising if variations in arterialpulse pressure were <13%.Measurements and Main Results: Pleth variability index, variationsin arterial pulse pressure, and cardiac output estimated byechocardiography were recorded before and after fluid challenge.Fluid responsiveness was defined as an increase in cardiac output of>15%. Twenty-one patients were responders and 19 were nonresponders.Mean SD pleth variability index (28% 13% vs. 11%4%) and arterial pulse pressure variation (22% 11% vs. 5% 2%)values at baseline were significantly higher in responders than innonresponders. The pleth variability index threshold value of 17%allowed discrimination between responders and nonresponders witha sensitivity of 95% (95% confidence interval, 74% to 100%) and aspecificity of 91% (95% confidence interval, 70% to 99%). The plethvariability index at baseline correlated (r .72, p < .0001) with thepercentage change in carbon monoxide induced by fluid challenge,suggesting that a higher pleth variability index at baseline willcorrelate with a higher percentage change in carbon monoxide aftervolume expansion.Conclusions: The pleth variability index can predict fluid responsivenessnoninvasively in intensive care unit patients undermechanical ventilation.Loupec T et al. Crit Care Med 2011 Vol. 39, No. 2
14 PVI to Help Clinicians Predict Hypotension During Surgery Background: The pleth variability index (PVI) is a newalgorithm used for automatic estimation of respiratoryvariations in pulse oximeter waveform amplitude, whichmight predict fluid responsiveness. Because anesthesiainducedhypotension may be partly related to patientvolume status, we speculated that pre-anesthesia PVIwould be able to identify high-risk patients for significantblood pressure decrease during anesthesia induction.Methods: We measured the PVI, heart rate (HR), systolicblood pressure (SBP), diastolic blood pressure (DBP), andmean arterial pressure (MAP) in 76 adult healthy patientsunder light sedation with fentanyl to obtain pre-anesthesiacontrol values. Anesthesia was induced with bolus administrationsof 1.8mg/kg propofol and 0.6mg/kg rocuronium.During the 3-min period from the start of propofoladministration, HR, SBP, DBP, and MAP were measured at30-s intervals.Results: HR, SBP, DBP, and MAP were significantly decreasedafter propofol administration by 8.5%, 33%, 23%,and 26%, respectively, as compared with the pre-anesthesiacontrol values. Linear regression analysis that comparedpre-anesthesia PVI with the decrease in MAPyielded an r value of Decreases in SBP and DBPwere moderately correlated with pre-anesthesia PVI, whileHR was not. By classifying PVI 415 as positive, a MAPdecrease 425mmHg could be predicted, with sensitivity,specificity, positive predictive, and negative predictivevalues of 0.79, 0.71, 0.73, and 0.77, respectively.Conclusion: Pre-anesthesia PVI can predict a decrease inMAP during anesthesia induction with propofol. Its measurementmay be useful to identify high-risk patients fordeveloping severe hypotension during anesthesia induction.Tsuchiya M et al. Acta Anaesthesiol Scand
15 PVI to Help Clinicians Predict Hemodynamic Instability by PEEP BACKGROUND: Pleth variability index (PVI) is a new algorithm allowing automated and continuousmonitoring of respiratory variations in the pulse oximetry plethysmographic waveformamplitude. PVI can predict fluid responsiveness noninvasively in mechanically ventilated patientsduring general anesthesia. We hypothesized that PVI could predict the hemodynamic effects of10 cm H2O positive end-expiratory pressure (PEEP).METHODS: We studied 21 mechanically ventilated and sedated patients in the postoperativeperiod after coronary artery bypass grafting. Patients were monitored with a pulmonary arterycatheter and a pulse oximeter sensor attached to the index finger. Hemodynamic data (cardiacindex [CI], PVI, pulse pressure variation, central venous pressure) were recorded at 3 successivetidal volumes (VT) (6, 8, and 10 mL/kg body weight) during zero end-expiratory pressure (ZEEP)and then after addition of a 10 cm H2O PEEP for each VT. Hemodynamically unstable patientswere defined as those with a 15% decrease in CI after the addition of PEEP.RESULTS: PEEP induced changes in CI and PVI for VT of 8 and 10 mL/kg. Hemodynamicinstability occurred in 5 patients for a VT of 6 mL/kg, in 6 patients for a VT of 8 mL/kg, and in9 patients for a VT of 10 mL/kg. For VT of 8 mL/kg, a PVI threshold value of 12% during ZEEPpredicted hemodynamic instability with a sensitivity of 83% and a specificity of 80% (area underthe receiver operating characteristic curve 0.806; P 0.03). For VT of 10 mL/kg, a PVI thresholdvalue of 13% during ZEEP predicted hemodynamic instability with a sensitivity of 78% and aspecificity of 83% (area under the receiver operating characteristic curve 0.829; P 0.01).CONCLUSIONS: PVI may be useful in automatically and noninvasively detecting the hemodynamiceffects of PEEP when VT is 8 mL/kg in ventilated and sedated patients with acceptablesensitivity and specificity.Desebbe O et al. Anesth Analg 2010;110:792–798.
16 PVI to Help Clinicians Improve Fluid Management and Reduce Patient Risk BACKGROUND: Dynamic variables predict fluid responsiveness and may improve fluid managementduring surgery. We investigated whether displaying the variability in the pulse oximeterplethysmogram (pleth variability index; PVI) would guide intraoperative fluid management andimprove circulation as assessed by lactate levels.METHODS: Eighty-two patients scheduled for major abdominal surgery were randomized into 2groups to compare intraoperative PVI-directed fluid management (PVI group) versus standardcare (control group). After the induction of general anesthesia, the PVI group received a 500-mLcrystalloid bolus and a crystalloid infusion of 2 mL kg1 h1. Colloids of 250 mL wereadministered if the PVI was 13%. Vasoactive drug support was given to maintain the meanarterial blood pressure above 65 mm Hg. In the control group, an infusion of 500 mL ofcrystalloids was followed by fluid management on the basis of fluid challenges and their effectson mean arterial blood and central venous pressure. Perioperative lactate levels, hemodynamicdata, and postoperative complications were recorded prospectively.RESULTS: Intraoperative crystalloids and total volume infused were significantly lower in thegoal-directed PVI group. Lactate levels were significantly lower in the PVI group during surgery and48 hours after surgery (P 0.05).CONCLUSIONS: PVI-based goal-directed fluid management reduced the volume of intraoperativefluid infused and reduced intraoperative and postoperative lactate levels.Forget P et al. Anesth Analg 2010.
17 Overall Conclusions: Clinical Utility of PVI Fluid administration is critical to optimizing patient statusTraditional methods to guide fluid administration are not sensitive or specific 1Newer methods to improve fluid administration may improve patient outcomes but are impractical, invasive, or costly 2PVI is noninvasive and proven to predict fluid responsiveness in mechanically ventilated patients in the OR and ICU 3,4PVI improves fluid management and reduces patient risk as evidenced by lower lactate levels 51 Michard F, Teboul JL. Chest Jun;121(6): Joshi G. et al. Anesth Analg. 2005; 101: Cannesson M et al. Br J Anaesth Aug;101(2): Feissel M et al. Critical Care ;13(1):P Forget P et.al. Critical Care. 2009; 13(1):P204.
19 PVI to Assess Fluid Responsiveness During Surgery: Summary Methods25 surgical patients under general anesthesiaRecorded CVP, PCWP, cardiac index, delta PP, PVIBefore and after volume expansion (500 ml of hetastarch 6%)Fluid responsiveness was defined >15% increase in cardiac indexResultsResponse to volume expansionCardiac index increase from 2.0 to 2.5 l/min/m2PVI decrease of 14 to 9PVI >14% before volume expansionDiscriminated between responders and non-responders with 81% sensitivity and 100% specificitySignificant relationship between PVI before volume expansion and change in cardiac index after volume expansion (R=0.67; P<0.01)ConclusionPVI can predict fluid responsiveness non-invasively in mechanically ventilated patients during general anesthesiaCannesson M et al. Br J Anaesth Aug;101(2):200-6
20 PVI to Help Clinicians Assess Fluid Responsiveness During Surgery: Summary Method20 patients scheduled for elective major abdominal surgeryAfter induction of anesthesia, all hemodynamic variables were recorded immediately before (T1) and subsequent to volume replacement (T2) by infusionResultsThe volume-induced increase in SVI was at least 15% in 15 patients (responders) and less than 15% in five patients (non-responders).Baseline SVV correlated significantly with changes in SVI as did baseline PVI whereas baseline values of central venous pressure showed no correlation to DSVINo significant difference between the area under the receiver operating characteristic curve for SVV (0.993) and PVI (0.973)The best threshold values to predict fluid responsiveness were more than 11% for SVV and more than 9.5% for PVIConclusionSVV and PVI can serve as valid indicators of fluid responsiveness in mechanically ventilated patients undergoing major surgeryZimmermann M, et al. Eur J Anaesthesiol. 2010;27(66):
21 PVI to Assess Fluid Responsiveness in the ICU: Summary MethodForty mechanically ventilated patients with circulatory insufficiencyFluid challenge with 500 mL of 130/0.4 hydroxyethyl-starch if respiratory variations in arterial pulse pressure were >13% or with passive leg raising if variations in arterial pulse pressure were <13%Results21 were responders and 19 were non-responders.Differences in responders vs. non-respondersPVI % vs % (p<0.05)Arterial pulse pressure variation % vs % (p<0.05)PVI correlation with change in cardiac output after fluid challenge (0.72, p<0.0001)Values at baseline were significantly higher in responders than in non-respondersConclusionPVI can predict fluid responsiveness noninvasively in intensive care unit patients under mechanical ventilationLoupec T et al. Crit Care Med 2011 Vol. 39, No. 2
22 PVI to Help Clinicians Predict Hypotension During Surgery: Summary MethodMeasured PVI, HR, SBP, DBP, and MAP in 76 adult healthy patients under light sedation with fentanyl to obtain pre-anesthesia control valuesAnesthesia induced w/bolus administrations of 1.8 mg/kg propofol and 0.6 mg/kg rocuroniumDuring the 3-min period from the start of propofol administration, HR, SBP, DBP, and MAP were measured at 30-s intervalsResultsHR, SBP, DBP, and MAP were significantly decreased after propofol administration by 8.5%, 33%, 23%, and 26%, respectively, as compared with the pre-anesthesia control valuesLinear regression analysis that compared pre-anesthesia PVI with the decrease in MAP yielded an r value of -0.73ConclusionPVI can predict a decrease in MAP during anesthesia induction with propofol. Its measurement may be useful to identify high-risk patients for developing severe hypotension during anesthesia inductionTsuchiya Acta Anaesthesiol Scand
23 PVI to Help Clinicians Predict Hemodynamic Instability by PEEP: Summary Method21 mechanically ventilated and sedated patients in the postoperativeperiod after coronary artery bypass graftingPatients were monitored with a pulmonary artery catheter and a pulse oximeter sensor attached to the index fingerCardiac index [CI], PVI, pulse pressure variation, central venous pressure) were recorded at 3 successive tidal volumesResultsPEEP induced changes in CI and PVI for VT of 8 and 10 mL/kg.For VT of 8 mL/kg, a PVI threshold value of 12% during ZEEP predicted hemodynamic instability with a sensitivity of 83% and a specificity of 80% (area under the receiver operating characteristic curve 0.806; P 0.03)ConclusionPVI may be useful in automatically and noninvasively detecting the hemodynamic effects of PEEPDesebbe O et al. Anesth Analg 2010;110:792–798.
24 Optimization of Fluid Management by PVI: Summary MethodsRandomized Clinical TrialIntra-operative PVI-directed fluid management vs. standard careAbdominal surgery patientsPVI Group – 41 patients500 ml crystalloids followed by 2ml/kg/hrColloids added at 250ml for PVI values between 10-13Control Group – 41 patients500 ml crystalloids followed by standard fluid management care (challenges and CVP)OutcomesPrimary: Perioperative lactate levelsSecondary: Hemodynamic data and post-op complicationsForget P et al. Anesth Analg 2010.
25 Optimization of Fluid Management by PVI: Summary Cont. ResultsPVI group had lower lactate levelsMax intraoperative (1.2 vs. 1.6, p<0.05)24 hours (1.4 vs. 1.8, p<0.05)48 hours (1.2 vs. 1.4, p<0.05)PVI group received lower amounts of intra-operative crystalloids1363 vs mL (p<0.01)No significant differences in morbidity or mortalityConclusionPVI-based goal-directed fluid management reduced the volume of intraoperative fluid infused and reduced intraoperative and postoperative lactate levelsForget P et al. Anesth Analg 2010.