Hemodynamic Echocardiography Calculation.pptx

CALCUATION OF
HEMODYNAMIC WITH
ECHOCARDIOGRAPHY

Introduction
■ Hemodynamics is the physics of blood circulation study of the the control of
circulation and the factors that alter it .
■ Main function of blood circulation: ensure adequate tissue perfusion
■ Related to CO and Vascular resistance
■ CO= SVxHR
■ SV affected by preload, contractility and afterload
Stephen J. Huang. Appreciating the strength and weakness of Tranthoracic
Echocardiography in Hemodynamic Assesment. 2011

WHY DO WE MONITOR?
• Preload, contractility, afterload, and oxygen transport
are commonly abnormal in the critically ill
• Inadequate resuscitation and failure to restore cellular
oxygen delivery and organ perfusion results in
multiple system organ failure (MSOF) and death
• Optimization of cardiopulmonary function during
critical illness reduces organ failure and improves
survival
• Accurate assessment of hemodynamic function and
goal-directed resuscitation is essential to improving
patient outcome

Objectives of hemodynamic
monitoring in critical care
Monitor patient’s response to
cardiovascular therapy and to titrate
medications as necessary
Differentiate causes of
hemodynamic instability and
circulatory shock
Detecting impending cardiovascular
crisis before organ damage occurs

CURRENT MONITORING TECHNOLOGIES
Invasive Monitoring Techniques
• Bolus thermodilution PAC
• Continuous thermodilution PAC
• Central venous oxygen saturation (ScvO2)
• Arterial Pulse Contour Analysis
Noninvasive Monitoring Techniques
• Ultrasound
• Thoracic Electrical Bioimpedance
• Partial Carbon Dioxide Rebreathing

Echocardiography as Non-Invasive
Hemodynamic Monitoring
■ Truly non invasive
■ Most extensively studied with good correlation with invasive
measurement
■ Pros: Repeatability, virtually no side effects, available within short time
frame
■ Cons: operator-dependent, technical errors

Hemodynamic monitoring
utilizing echocardiography
LV performance
preload contractility afterload
LV filling pressure • FS / EF
• SV / CO
(Chest 2005;127:379-390)
SVR
( Oka,Konstadt; Clinical TEE 1996)
In daily practice: the assessment of cardiac output, fluid
status, and intravascular pressure

Hemodynamic assessment by
echocardiography
Assessment of fluid
responsiveness
Volume
expansion:
- Volume
challenge
- PLR
Changes in
CO or SV
Respiratory
variation
- SV variation
- IVC variability
index
- IVC distensibilty
index
Estimation of RA
pressure
IVC collapsibility
index
Estimation of
cardiac output
Doppler
echocardiography
Stephen J. Huang. Appreciating the strength and weakness of Tranthoracic
Echocardiography in Hemodynamic Assesment. 2011

Estimation of Cardiac Output –What Data Do We
Need?
After LVOT diameter and VTI,
Then calculate…….
SV = 0.785 x (LVOT Ø)2 x LVOT VTI
CO = SV x HR/1000
LVOT diameter: Left Ventricle Outflow Tract diameter
(cm)
LVOT VTI : Velocity Time Integral (cm)
SV : Stroke Volume (mL)
Normal SV : 60—100 mL
Normal CO : 4-8 L/minute
Normal Cardiac Index (CI): 2.5 – 4.0
L/minute/m2

Need?
1. LVOT Diameter
LVOT diameter: Left Ventricle Outflow Tract
diameter (cm)

Need?
2. LVOT VTI
LVOT diameter: Left Ventricle Outflow Tract
diameter (cm)
CO Cardiac Output (L/minute)

■ Menghitung stroke volume (SV)

■ Menghitung Cardiac Output (CO)

■ Menghitung Cardiac Index (CI)

Estimation of Cardiac
Output
Limitations of Cardiac Output Estimation by
Echocardiography:
 Cannot provide continuous monitoring
 Measurements and accuracies can be affected by
patient’s position, effects of mechanical ventilation,
arrythmias, Doppler angle error, poor angle alignment
 With TTE: suboptimal ultrasound windows: poor image
quality

SNIFF
Collapsibility Index:
(Dmax-Dmin)
Dmax
ASSESSMENT OF RA PRESSURE OR CVP
IVC VIEW

Assessment of Right Atrium Pressure (RAp)
by Echocardiography
CAUTIONS:
 Not to be used in mechanically ventilated patients
 Estimation of RAp  rough estimation of PRELOAD  not
synonymous wih measurement of fluid status
LIMITATIONS
 Body position
 Poor image quality
 Measurement errors
 Motion artefact
 Right heart failure
 Severe tricuspid regurgitation

Estimation of Systemic Vascular Resistance
(SVR)
SVR= (MAP-RAp) x 80
CO
MAP : Mean Arterial Pressure
(mmHg)
RAp : Right Atrium Pressure
(mmHg)
Normal Value of SVR: 800 – 1200 dyne/sec/cm-5

■Status Volume Evaluation
and Fluid Responsiveness

Hemodynamic problem in critical
care
 Hemodynamic failure is a common problem in the
intensive care unit
 Hypovolemia may suspected in many clinical situations
frequent cause of shock
 Volume loading often first-line therapy to improve
hemodynamic status
 Only 40-70% response to fluid challenge
 Significant disadvantages to inappropriate fluid
administration
Dellinger RP. Critical Care Med. 2013
Michard F. Chest. 2002
Wiedeman HP. NEJM. 2006

Basic Volume Status
Assessment
Easy in severe hypovolemia
Easy in clear volume overload
Difficult in less severe hypovolemia or in
significant cardiac disease
Consider pre-existing cardiac disease
Consider respiratory status

Aim of Fluid Responsiveness Assessment
 To determine which patients with circulatory failure
that will get benefit from fluid administration
 To predict which patients with acute circulatory failure
will respond to fluid by a significant increase in cardiac
output
 Must answer key question:
should the patient receive additional volume
infusions?
Monnet, Teboul. Critical Care, 2013 17:217.
Slama, Maizel, Mayo. Echocardiographic Evaluation of Preload Responsiveness. 2009

Key
Principles
 Cardiac output =
Heart Rate x Stroke Volume
 Increase in venous return
(preload)
 Increase in stroke volume (Frank-
Starling Curve) until
some extend
 Concept of Preload reserve vs
No preload reserve
Sherwood. Human Physiology, 7th Ed. 2010
Monnet, Teboul. Critical Care, 2013 17:217

Preload
optimization
 Traditional parameters estimating blood volume, central
venous pressure or pulmonary artery systolic pressure have
not been proven reliable in predicting fluid responsiveness
 Echocardiography may offer useful parameters to
determine the critical patients’ preload and volume status
assessment: ventricular volume changes, respiratory
changes in inferior vena cava or superior vena cava
(with TEE) or respiratory changes in aortic flow velocity
Marik P, et al. Chest 2008, 134; 172-178
Bermejo et al. Current Cardiology Reviews, 2011, 7, 146-156
Charron C. Current Opinion Critical Care 2006

Adverse Effect of Fluid Administration in fluid
non- responsive patients
 Increasing hydrostatic pressure  pulmonary edema
 Respiratory failure
 Prone to infection
 Fluid extravasation to interstitial compartment
 Diffuse peripheral edema  compromise tissue oxygenation
 Cerebral edema
 Disorder of electrolytes
 LV compression in acute cor pulmonale cases
Slama, Maizel, Mayo. Echocardiographic Evaluation of Preload Responsiveness.2009

Methods to Asses Fluid
Responsiveness
Clinical parameter: heart rate, blood
pressure, capillary refill time
 Laboratory: blood lactates, mixed vein
saturation
 Invasive technique
Central venous pressure
PCWP (with Swan Ganz catheter)
 Non-invasive technique
Marik, Lemson. Br J Anaesth. 2014;112(4):617-620

Invasive
methods
 Central venous pressure (with central venous catheter)
 PCWP (with Swan Ganz catheter)
Image courtesy of clinicalgate.com and Adam

PCWP (Pulmonary Capillary Wedge Pressure)
 PCWP or PAOP (pulmonary artery occlusion
pressure) obtained from Swan Ganz catether
reflects cardiac filling pressure
 Changes in PCWP was also believed to be predictor of
fluid responsiveness recent studies showed no
correlation
 PCWP is not generally useful in predicting volume
responsiveness...except in patients with very low
value of PCWP (very rarely encountered in ICU)
Coudray, Romand, Treggiari. Crit Care Med. 2005; 33:2757–2762

Non-Invasive
Methods
 Performed with ultrasound/echocardiography by
cardiologist/intensivist
 Methods:
 Changes of inferior vena cava (IVC) diameter during
mechanical ventilation – distensibility index
 Variation of velocity-time integral with respiration
 Passive leg raising (PLR) test
 Mini fluid challenge test
 End-expiratory occlusion test

Left Ventricular Study in
hypovolemia
 The visualization of left
ventricular end systolic
obliteration “kissing papillary
muscle sign”
 TTE parasternal short axis
view at the level of the
papillary muscles
 Or TEE trans-gastric view at
level of the papillary muscle
Leung, et al. Anesthesiology 1994;81:1102-1109
Beaulieu Y, Marik PE. Chest 2005;128;881-895

Left Ventricular Study in
hypovolemia

Leung, et al. Anesthesiology 1994;81:1102-1109
Beaulieu Y, Marik PE. Chest 2005;128;881-895
Schiller NB, Shah PM, Crawford M, et al. J Am Soc Echocardiogr 1989; 2:358 –367

LVEDA variation with
respiration
Assessed LV diastolic area (LVEDA) changes by
TEE from short- axis view
In mechanically ventilated patients
16% respiratory variation of LVEDA between
inspiration and expiration predicted fluid
responsiveness with a sensitivity of 92% and a
specificity of 83%
Cannesson M, Slieker J, et all. Crit Care. 2006;10:R171

LVEDA variation with
loading
Range for value of normal LVEDA in the short axis are from 9.5 to 22 cm2
Cheung, et al. Anesthesiology 1994;81:376-387
Schiller NB, et al. J Am Soc Echocardiogr 1989; 2:358 –367
Decrease of 3 cm2
= 10% EBV loss

Changes in stroke volume and IVC diameter
caused by mechanical ventilation
Mandeville JC, Colebourn CL. Critical Care Research and Practice.
doi:10.1155/2012/513480

Respiratory changes in Cava Veins Analysis:
Superior Vena Cava
 Superior vena cava was
recorded from TEE longitudinal
view at 90– 100◦
 Collapsibility index: Maximal
diameter on expiration − minimal
diameter on inspiration)/maximal
diameter on expiration
 Cutoff values of 36% for SVC
collapsibility index (sensitivity 90%,
specificity 100%) were found to
accurately separate responders
and non-responders
Vieillard-Baron A, Augarde R, Prin P, et al. Anesthesiology. 2001;95:1083–1088
Significant superior vena cava collapsibility

Inferior Vena Cava
 IVC diameter analyzed from a
longitudinal subcostal view and
recorded by using M- mode
 Measured 1–2 cm distal to the
junction of the right atrium.
 Small diameter was: 1.2 cm
 Normal diameter: 1.2 cm and 1.7 cm
 Dilated diameter 1.7–2.5 cm,
markedly dilated > 2.6 cm
Breitkreutz L, Walcher F, et al Eur J Trauma Emerg Surg 2009;35:347–56
Lang RM, Bierig M, et al J Am Soc Echocardiogr 2005;18:1440 – 63

Inferior Vena Cava
 In spontaneously breathing
patients, the following
measurements suggest a patient is
likely to be fluid responsive:
 IVC measuring < 2 cmin
diameter
 IVC collapse > 40-50% witheach
breath  70% sensitivity and 80%
specificity
Barbier C, Loubi`eres Y, Schmit C, et al. Intensive Care Med. 2004;30:1740–1746
Muller L, Bobbia X, Toumi M, et al.. Crit Care 2012; 16:R188
Evans D, Ferraioli G. J Ultrasound Med 2014; 33:3–7
The image on the left depicts substantialrespiratory
variations in IVC diameter suggestive of volume
responsiveness. The patient on the right is unlikely to
positively respond to volume resuscitation

IVC collapsibility index
 Vena cava collapsibility index
predict hemodynamic response to
fluid challenge patients with septic
shock who are not mechanically
ventilated
 Measurement usingTTE
 IVC collapsibility index: 15% or
greater  fluid responsiveness
(positive predictive value 62%
and negative predictive value,
100%)
Lanspa MJ, Grissom CK. Shock. 2013; 39: 155-160
Vena cava collapsibility index

Distensibility index of IVC
 IVC diameter changes during
mechanical ventilation were
measured to predict fluid
responsiveness.
 Accurately separate responders
and non-responders of fluid
infusion in mechanically ventilated
patients
Significant inferior vena cava distensibility in a
mechanically ventilated patient

Distensibility index of IVC
Cutoff values of 18% (by using
max–min/min) a sensitivity
and specificity of 90% (1)
Cutoff values of 12% (by using
max–min/mean value) high
sensitivity 93% and specificity
92% (2)
(1) Barbier C, Loubi`eres Y, Schmit C, et al. Intensive Care Med. 2004;30:1740–1746
(2) Feissel M, Michard F, Faller JP, et al. Intensive Care Med. 2004;30:1834–1837
(Dmax − Dmin)
Dmin
(Dmax−Dmin)
0.5(Dm
a
x+Dmin)

Respiratory variations of maximal aortic blood
flow velocity
 Evaluation by TTE and TEE:
Apical 5-chamber view with
spectral Doppler gates set at
5 mm within the LVOT in
measure the LVOT velocity
time integral
Evans D, et al. J Ultrasound Med 2014; 33:3–7

Respiratory variations of
maximal
aortic blood flow velocity
 Maximal aortic blood flow VTI variation measured
with TEE or TTE in a mechanically ventilatedpatient
 Predicts increases in cardiac output after fluid
infusion in patients with shock  high sensitivity,
specificity, and predictive value
 Variation of maximal velocity (Vmax) with
respiration responder vs non-responder:
A cutoff value of 12% for maximal velocity
Feissel M, Michard F. Chest. 2001;119:867–873
Charron C, Fessenmeyer C, Cosson C, et al. Anesth Analg. 2006; 102:1511–1517

Respiratory variations of maximal aortic blood
flow velocity
Presence of significant respiratory variations of Vmax. (1.29 − 1.09/1.19 = 17%.
Same patient after volume expansion, regression of the respiratory variations (1.37
− 1.32/1.34 = 4%)

Respiratory variations of aortic
blood
flow velocity VTI
 Aortic blood flow VTI variation measured with TEE or
TTE predicts increases in cardiac output after fluid
infusion in mechanically ventilated patients with shock
 High sensitivity, specificity, and predictive value
 Variation of VTI with respiration responder vs non-
responder
 A cutoff 20% for respiratory cycle changes of
aortic VTI
Feissel M, Michard F. Chest. 2001;119:867–873
Charron C, Fessenmeyer C, Cosson C, et al. Anesth Analg. 2006; 102:1511–1517

Respiratory variations of aortic blood flow
velocity VTI
Presence of significant respiratory variations of VTI: (VTImax − VTImin/[VTImax + VTI
min/2] (20.7 − 17.3/19 = 18%). Same patient after volume expansion, regression of the
respiratory variations: VTI (23.5 − 22.3/22.9 = 5%)

Passive Leg Raising
(PLR) test
PLR rapidly mobilizes about 300 mL of blood
from the lower limbs to the intrathoracic
compartment and reproduces the effects of
volume expansion
 It is reversible and devoid of any risks of
volume expansion
 In spontaneous breathing and mechanically
ventilated patients
Boulain T, Achard JM, Teboul JL, et al. Chest. 2002;121:1245–1252
Lafanech`ere A, P`ene F, Goulenok C, et al. Crit Care. 2006;10:R132

Passive Leg Raising
(PLR) test
Mandeville JC, Colebourn CL. Critical Care Research and Practice. doi:10.1155/2012/513480

Passive Leg Raising
(PLR) test
 Percent change is [(stroke volume after passive leg
raising – stroke volume before passive leg raising)/stroke
volume after passive leg raising] × 100%
 A threshold of 10 to 15 percent increment of stroke
volume or cardiac output
 All studies showed good sensitivity (77 to 100 %) and
specificity (88 to 99 %)
 PLR predicted the correct response to volume
expansion in patients with arrhythmia
Mandeville JC, Colebourn CL. Critical Care Research and Practice. doi:10.1155/2012/513480
Thiel SW, Kollef MH. Critical Care, vol. 13, no. 4, article R111, 2009

The End-expiratory Occlusion Test
 During mechanical ventilation, inspiration cyclically
decreases the left cardiac preload. An end- expiratory
occlusion may prevent the cyclic impediment in left
cardiac preload and may act like a ﬂuid challenge
 A 15-second end- expiratory occlusion test in ventilator
patient followed by 500 ml saline infusion increased
the arterial pulse pressure or the pulse contour-derived
cardiac index
Monnet X, Osman D, Ridel C et al. Crit Care Med 2009, 37: 951-956

The End-expiratory Occlusion Test
■  During the end-expiratory occlusion, fluid
responsiveness was predicted by:
■ an increase in pulse pressure >5% with a sensitivity of 87% and
a speciﬁcity of 100%
■ an increase in cardiac index >5% with a sensitivity of 91% and a
speciﬁcity of100%
■  This test can also be used in patients with
■ spontaneous breathing activity
Monnet X, Osman D, Ridel C et al. Crit Care Med 2009, 37: 951-956

The 'mini' Fluid
Challenge
 Give mini (small) amount of fluid (100 cc) vs classical
fluid challenge (300-500 cc)
 It consists of administering 100 ml of colloid over 1 min
and observe the effects of this 'mini' fluid challenge on
stroke volume, as measured by the sub aortic velocity time
index using TTE
 An increase in the velocity time index of more than 10%
predicted fluid responsiveness with a sensitivity of 95% and
a specificity of 78%
 Small volume of fluid is unlikely to induce fluid overload

Significant methodological limitation determination of
volume responsiveness using echocardiography
 All require that the patient be on mechanical
ventilation and passive in their interaction with the
ventilator.
 The patient can make no spontaneous breathing
effort during the measurement and must be in a
regular heart rhythm.
 The degree of respiratory variation is contingent on
the change of intrathoracic pressure.
 Tidal volume and positive end-expiratory pressure
(PEEP) levels are known to influence pulse pressure
variation

Decision-making process in fluid administration

Which Methods to
Use?
Which methods we should use?
Depend of patient condition
Spontaneous breathing vs mechanically ventilated

Take Home
Message
 Volume status and fluid responsiveness assessment in critically ill patients
using echocardiography is applicable, safe and accurate.
 Dynamic parameters determined by echocardiography are superior to static
measurements of preload for the determination of volume responsiveness.
 Inferior vena cava diameter and trans-aortic Doppler signal changes with
the respiratory cycle or passive leg raising has strong predictive power.
 Limitations of the technique relate to patient tolerance of the procedure,
adequacy of acoustic windows, and operator skill.

Echo findings in severe
hypovolemia
 Left ventricular study
 Reduced LV end diastolic area
 End systolic LV obliteration (kissing walls)
 Small IVC diameter
 Spontaneous respiration end expiratory dimension < 9mm
 Mechanical ventilation end expiratory dimension < 15 mm
 IVC respiratory variation
 Spontaneous respiration: > 50 %
 Mechanical ventilation > 18%

Mean right atrial pressure according to
respiratory changes in inferior cava vein

Central Venous
Pressure
 Central venous pressure (CVP) =P
 CVP can reflect a volume increase in RA pressures or decrease in RVcontractility
 can be both.
 Need to be monitored in conjunction with other monitors(CVP&MAP)
 The main limitations of CVP monitoring:
(a)it does not allow to measure cardiac output
(b)it does not provide reliable information on the status of the pulmonary
circulation in the presence of left ventricular dysfunction

Characteristic of all included
studies
Study Technique Patient group Selection Ventilation Rhythm Volumeand type
Time
(min)
Response
criteria
Barbier et al. [17] IVCDI Mixed ICU All mand Any 7mL/kgcolloid 30
Feisselet al. [18] ∆DIVC Medical ICU
Shock (sepsis) and
acutelunginjury
Shock(sepsis) All mand Any 8mL/kgcolloid 20
>15%
COTTE
>15%
COTTE
hypovolaemia) SR,or AF SVTTE
(unspecified) COTTE
haemorrhage) SVTTE
(liver surgery) colloid COTTE
(unspecified) or colloid SVTTE
Lamiaet al. [14] PLR Medical ICU
Shock (sepsisor
All spont
Regular
500mL crystalloid 15
>15%
Maizel etal. [13] PLR Mixed ICU
Shock
All spont Regular SR 500mL crystalloid 15
>12%
Biaiset al. [15] PLR Surgical ICU
Shock (sepsisor
All spont Any 500crystalloid 15
>15%
Biaiswt al. [19] SVV Surgical ICU
Post-operative
All mand Regular SR
20mL/kg/m2
20
>15%
Thiel et al. [16] PLR Medical ICU
Shock
Mixed Any
500mL crystalloid
Unspec
>15%
Preáuetal. [12] PLR Medical ICU
Shock (sepsisor
All spont Regular SR 500mL colloid <30
>15%
acutepancreatitis) SVTTE
Selection: inclusion criteria summary, PLR: passive leg raising, spont: spontaneous respiratory effort whether or not on mechanical ventilation, mand:
ventilator giving mandatorybreathsonly and patient fully adaptedto ventilator, SR:sinusrhythm, AF: atrial fibrillation, TTE: transthoracicechocardiography,
SV:strokevolume, CO: cardiac output, ∆DIVC changein IVC diameter adjusted by themean (seetext), IVC DI: IVC distensibility index (seetext),andunspec:
unspecified time.
Mandeville JC, Colebourn CL. Critical Care Research and Practice.doi:10.1155/2012/513480

Collated result of all included
studies
Study
Number
of tests
Predictivetest Threshold
RespIntra-obs Inter-obs
% % %
AUC
(ROC)
Lamiaet al. [14] 24 ≥ 12.5% 54 2.8 ± 2.2 3.2 ± 2.5 0.96 ± 0.04
Sens Spec PLiR NLiR PPV NPV r
77 99 77 0.23 0.79
Maizel etal. [13] 34 50 4.2 ± 3.9
4.2 ± 3.9
6.5 ± 5.5 0.90 ± 0.06
6.2 ± 4.2 0.95 ± 0.04
0.96 ± 0.03 100
Biais et al. [ 15]
Thiel et al. [ 16]
Preáuetal. [12]
67
46
41
SI
SI
SI
PLR SVIor
CO rise
PLRCO rise ≥ 12%
PLRSVrise ≥12%
34 PLRSVrise ≥13%
102 PLRSVrise ≥15%
34 PLRSVrise ≥ 10%
PLRdVFrise ≥ 8%
0.89 ± 0.04
0.90 ± 0.04
0.93 ± 0.04
63 89 5.73 0.42 85 76 0.75
69 89 6.27 0.35 83 73 0.57
80 5.00 0.00
81 93 11.57 0.20 91 85
86 90 8.60 0.16 86 90 0.74
86 80 4.30 0.18 75 89 0.58
Biaiset al.[15] 30 SVV ≥ 9% 47 SI 0.95 100 88 8.33 0.00 0.80
Barbier et al. [17] 23
Feissel et al. [18] 39
IVCDI
∆DIVC
≥ 18%
≥ 12%
41 8.7 ± 9
41 3 ± 4
6.3± 8 0.91 ± 0.07 90 90 9.00 0.11
SI 93 92
0.90
0.82
Threshold: cut-off between responders and nonresponders, Resp: proportion responding to fluid load, Intra-obs: intraobserver variability, Inter-obs:
interobserver variability, AUC(ROC): area under thereceiver-operator curve, Sens: Sensitivity, Spec: Specificity, PLiR: positivelikelihood ratio, NLiR: negative
likelihood ratio, PPV: positivepredictivevalue, NPV: negativepredictivevalue, r : correlation coefficient, PLR: Passiveleg raising, SI: singleinvestigator/reader,
CO: cardiac output, SV: stroke volume, dVF: change in femoral artery velocity as measured by Doppler, SVI: stroke volume index, LVEDAI: left ventricular
end-diastolic area, E/Ea: mitral E-wave velocity/mitral annulus E velocity measured by tissue Doppler, ∆DIVC: change in IVC diameter (D) as calculated by
(Dmax − Dmin)/0.5(Dmax + Dmin), IVC DI: IVC distensibilityindexcalculated by(Dmax − Dmin)/Dmin.
Mandeville JC, Colebourn CL. Critical Care Research and Practice.doi:10.1155/2012/513480

Hemodynamic Echocardiography Calculation.pptx

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