390 likes | 2.3k Views
Noninvasive and Continuous Fluid Responsiveness Monitoring with Pleth Variability Index (PVI). PVI Overview. Physiology Fluid administration challenges PVI method PVI clinical evidence. Physiology Background. Oxygen delivery components Cardiac output x oxygen saturation x hemoglobin
E N D
Noninvasive and Continuous Fluid Responsiveness Monitoring with Pleth Variability Index (PVI)
PVI Overview • Physiology • Fluid administration challenges • PVI method • PVI clinical evidence
Physiology Background • Oxygen delivery components • Cardiac output x oxygen saturation x hemoglobin • Cardiac output components • Stroke volume • Preload • Afterload (Systemic Vascular Resistance) • Contractility • Heart rate • Primary methods to increase cardiac output • Increase preload (volume expanders) • Increase contractility (inotropes) • Decrease afterload (vasodilators) • Key point • Administering volume may increase intravascular volume and preload but not stroke volume and cardiac output
Frank-Starling Relationship Stroke Volume 0 0 Preload
Fluid Administration Challenges • Fluid administration is critical to optimizing oxygen delivery by optimizing cardiac output 1 • Unnecessary fluid administration may be harmful2 • Traditional methods to guide fluid administration often fail to predict fluid responsiveness • Accurate only 50-60% of time 3 • Newer dynamic methods that can predict fluid responsiveness are invasive, complex, and/or costly 4 • Many patients are not candidates for this level of monitoring 1 Perel A. Anesth Analg. 2008; 106 (4):1031-33 2 Bundgaard-Nielsen M et al. Acta Anaesthesiol Scand. 2007; 51(3):331-40 3 Michard F et al. Chest. 2002; 121(6):2000-08 4 Joshi G et al. Anesth Analg. 2005; 101:601-5
Pleth Variability Index (PVI) • Masimo PVI is clinically proven to help clinicians assess fluid responsiveness and improve fluid management to reduce patient risk.1,2 • Once your Masimo Pulse CO-Oximeter is enabled with PVI-monitoring capability, PVI is automatically displayed for every patient receiving pulse oximetry monitoring 1 Cannesson M et al. Br J Anaesth. 2008;101(2):200-6. 2 Forget P et al. Anesth & Anal. 2010;111(4):910-4.
Pulse Pressure Variation and Changes in PPW During Ventilation Arterial Pulse Pressure Variation PPmax- PPmin (PPmax + PPmin) ÷ 2 ΔPP= Pleth Waveform Variation PPWmax – PPWmin (PPWmax + PPWmin) ÷ 2 ΔPPW= Ventilatory Cycle PPWmax PPWmin Adapted from: Cannesson M et al
PVI Calculation • Automated measurement • Changes in plethysmographic waveform amplitude over the respiratory cycle • PVI is a percentage from 1 to 100%: • 1 - no pleth variability • 100 - maximum pleth variability
PVI to Help Clinicians Optimize Preload / Cardiac Output Stroke Volume Lower PVI = Less likely to respond to fluid administration 10 % 24 % Higher PVI = More likely to respond to fluid administration 0 0 Preload Maxime Cannesson, MD, PhD
PVI to Help Clinicians Assess Fluid Responsiveness During Surgery: Similar to Arterial Pulse Pressure / Superior to CI, PCWP, CVP Adapted from Cannesson M. et. al. Br J Anesth 2008;101(2):200-206
PVI to Help Clinicians Assess Fluid Responsiveness During Surgery:Similar to Stroke Volume Variation / Superior to CVP Zimmermann M, et al. Eur J Anaesthesiol. 2010;27(66):555-561.
PVI to Assess Fluid Responsiveness in the ICUSimilar to Pulse Pressure Variation / Superior to Cardiac Output PPV PVI CO Loupec T et al. Crit Care Med 2011 Vol. 39, No. 2
PVI to Help Clinicians Predict Hypotension During Surgery Tsuchiya M et al. Acta Anaesthesiol Scand. 2010.
PVI to Help Clinicians Predict Hemodynamic Instability by PEEP Desebbe O et al. Anesth Analg 2010;110:792–798.
PVI to Help Clinicians Improve Fluid Management and Reduce Patient Risk Forget P et al. Anesth Analg 2010.
Overall Conclusions: Clinical Utility of PVI • Fluid administration is critical to optimizing patient status • Traditional methods to guide fluid administration are not sensitive or specific 1 • Newer methods to improve fluid administration may improve patient outcomes but are impractical, invasive, or costly 2 • PVI is noninvasive and proven to predict fluid responsiveness in mechanically ventilated patients in the OR and ICU 3,4 • PVI improves fluid management and reduces patient risk as evidenced by lower lactate levels 5 1 Michard F, Teboul JL. Chest. 2002 Jun;121(6):2000-8. 2 Joshi G. et al. Anesth Analg. 2005; 101:601. 3 Cannesson M et al. Br J Anaesth. 2008 Aug;101(2):200-6. 4Feissel M et al. Critical Care. 2009;13(1):P219.5 Forget P et.al. Critical Care. 2009; 13(1):P204.
PVI to Assess Fluid Responsiveness During Surgery: Summary • Methods • 25 surgical patients under general anesthesia • Recorded CVP, PCWP, cardiac index, delta PP, PVI • Before and after volume expansion (500 ml of hetastarch 6%) • Fluid responsiveness was defined >15% increase in cardiac index • Results • Response to volume expansion • Cardiac index increase from 2.0 to 2.5 l/min/m2 • PVI decrease of 14 to 9 • PVI >14% before volume expansion • Discriminated between responders and non-responders with 81% sensitivity and 100% specificity • Significant relationship between PVI before volume expansion and change in cardiac index after volume expansion (R=0.67; P<0.01) • Conclusion • PVI can predict fluid responsiveness non-invasively in mechanically ventilated patients during general anesthesia Cannesson M et al. Br J Anaesth. 2008 Aug;101(2):200-6
PVI to Help Clinicians Assess Fluid Responsiveness During Surgery: Summary • Method • 20 patients scheduled for elective major abdominal surgery • After induction of anesthesia, all hemodynamic variables were recorded immediately before (T1) and subsequent to volume replacement (T2) by infusion • Results • The 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 DSVI • No 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 PVI • Conclusion • SVV and PVI can serve as valid indicators of fluid responsiveness in mechanically ventilated patients undergoing major surgery Zimmermann M, et al. Eur J Anaesthesiol. 2010;27(66):555-561.
PVI to Assess Fluid Responsiveness in the ICU: Summary • Method • Forty mechanically ventilated patients with circulatory insufficiency • Fluid 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% • Results • 21 were responders and 19 were non-responders. • Differences in responders vs. non-responders • PVI 28 + 13% vs. 11 + 4% (p<0.05) • Arterial pulse pressure variation 22 + 11% vs. 5 + 2% (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-responders • Conclusion • PVI can predict fluid responsiveness noninvasively in intensive care unit patients under mechanical ventilation Loupec T et al. Crit Care Med 2011 Vol. 39, No. 2
PVI to Help Clinicians Predict Hypotension During Surgery: Summary • Method • Measured PVI, HR, SBP, DBP, and MAP in 76 adult healthy patients under light sedation with fentanyl to obtain pre-anesthesia control values • Anesthesia induced w/bolus administrations of 1.8 mg/kg propofol and 0.6 mg/kg rocuronium • During the 3-min period from the start of propofol administration, HR, SBP, DBP, and MAP were measured at 30-s intervals • Results • HR, 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 values • Linear regression analysis that compared pre-anesthesia PVI with the decrease in MAP yielded an r value of -0.73 • Conclusion • PVI 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 induction Tsuchiya Acta Anaesthesiol Scand. 2010.
PVI to Help Clinicians Predict Hemodynamic Instability by PEEP: Summary • Method • 21 mechanically ventilated and sedated patients in the postoperative period after coronary artery bypass grafting • Patients were monitored with a pulmonary artery catheter and a pulse oximeter sensor attached to the index finger • Cardiac index [CI], PVI, pulse pressure variation, central venous pressure) were recorded at 3 successive tidal volumes • Results • PEEP 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) • Conclusion • PVI may be useful in automatically and noninvasively detecting the hemodynamic effects of PEEP Desebbe O et al. Anesth Analg 2010;110:792–798.
Optimization of Fluid Management by PVI: Summary • Methods • Randomized Clinical Trial • Intra-operative PVI-directed fluid management vs. standard care • Abdominal surgery patients • PVI Group – 41 patients • 500 ml crystalloids followed by 2ml/kg/hr • Colloids added at 250ml for PVI values between 10-13 • Control Group – 41 patients • 500 ml crystalloids followed by standard fluid management care (challenges and CVP) • Outcomes • Primary: Perioperative lactate levels • Secondary: Hemodynamic data and post-op complications Forget P et al. Anesth Analg 2010.
Optimization of Fluid Management by PVI: Summary Cont. • Results • PVI group had lower lactate levels • Max 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 crystalloids • 1363 vs. 1818 mL (p<0.01) • No significant differences in morbidity or mortality • Conclusion • PVI-based goal-directed fluid management reduced the volume of intraoperative fluid infused and reduced intraoperative and postoperative lactate levels Forget P et al. Anesth Analg 2010.