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
•
•
Primary methods to increase cardiac output
•
•
Heart rate
•
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
3
Perel A. Anesth Analg. 2008; 106 (4):1031-33 2 Bundgaard-Nielsen M et al. Acta Anaesthesiol Scand. 2007; 51(3):331-40
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 PVImonitoring 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
ΔPP =
PPmax- PPmin
(PPmax + PPmin) ÷ 2
Pleth Waveform Variation
PPWmax – PPWmin
ΔPPW =
(PPWmax + PPWmin) ÷ 2
PPWmax
PPWmin
Ventilatory Cycle
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
2011 Radical-7
PVI to Help Clinicians
Optimize Preload / Cardiac Output
Stroke
Volume
10 %
24 %
0
0
Maxime Cannesson, MD, PhD
Lower PVI = Less likely to respond
to fluid administration
Higher PVI = More likely to respond to fluid administration
Preload
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 ICU
Similar 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.
et al. Br J Anaesth. 2008 Aug;101(2):200-6. 4 Feissel M et al. Critical Care. 2009;13(1):P219.
5 Forget P et.al. Critical Care. 2009; 13(1):P204.
3
Cannesson M
Reference Slides
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
•
•
•
Results
•
•
•
•
•
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
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
• Arterial pulse pressure variation
28 + 13% vs. 11 + 4% (p<0.05)
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
•
•
•
•
Results
•
•
•
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
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.