review of hemodynamic monitoring

REVIEW OF HD MONITORING

DR GHALEB ALMEKHLAFIMD,SFCCM,EDIC

HEMODYNAMICS

• DEFENITION-MOVEMENT• COMPONENTS-CIRCULATION• TARGETS-PERFUSION• PHYSIOLOGY/PATHOPHYSIOLOGY• METHODS OF MONITORING PARAMETERS AND VALIDITY DIAGNOSIS OR TREATMENT WHICH METHOD AND WHEN?

1-Myocardial contraction &heart rate

2-Vasoactivity

4factors that affecting the hemodynamic conditions

3-volume

C.O.= HR x Stroke Volume (60-130 Ml/beat)

Stroke Volume has three components 1. Preload 2. Afterload

3.Contractility

4-MICROCIRCULATION/PERFUSION

hypovolemia vascular tone depression

myocardial depression

Importance of assessing

the degree of each component

to select and apply the best therapeutic option

vasopressors inotropes

Hemodynamic failure in critically ill patients: 3 components

fluids

presence of associated lung injury

methodsClinical methods• Physical examination:

systemic clinical examination

• V/S:NI-BP, Heart rate• Skin, extremities• Urine output• Mental status

Classic methods

• A-LINE• Pulse waveform analysis• Invasive BP• CVP • PAC

Advanced methodsNon invasiveinvasiveLAB:

SCVO2,LA

• Clinical examination remains an important initial step in the diagnosis and risk stratification of critically ill patients.

• Individual vital signs often do not reflect hemodynamic status.• High or low pulse rate is neither sensitive nor specific for the

diagnosis of hemodynamic instability.• Respiratory rate lacks adequate specificity or sensitivity to serve

as a test for hemodynamic instability.• Skin or toe temperature is not a sensitive indicator of

hemodynamic instability.• Oliguria may have causes other than renal Hypoperfusion.

• TRENDS

Mottling score

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ARTERIAL LINE

Arterial waveform components

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Arterial Pressure (mmHg)

DAP: reflection of vasomotor tone

DAP

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Arterial Pressure (mmHg)

DAP: reflection of vasomotor tone

DAP: driving pressure for left coronary circulation

DAP

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PP

Arterial Pressure (mmHg)

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MAP

Arterial Pressure (mmHg)

MAP: driving pressure for perfusion of important organs (e.g. brain, kidney)

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Arterial Pressure (mmHg)

MAP: important hemodynamic target of resuscitation of shock states

MAP

MAP is a goal of resuscitation

• Correction of hypotension with a vasopressor allows improving organ perfusion and microcirculation

Which MAP value to target?

Target MAP

• increasing MAP above 65 mmHg results in little benefit

• Probably higher target value if: 1. History of chronic hypertension2. Elevated CVP3. Elevated abdominal pressure

Target blood pressure in circulatory shock

• We recommend individualizing the target blood pressure during shock resuscitation. Recommendation Level 1: QoE moderate (B)

• We recommend to initially target a MAP of ≥ 65 mmHg. Recommendation: Level 1; QoE low (C)

• We suggest a higher MAP in septic patients with a history of hypertension. Recommendation: Level 2; QoE low (B)

arterial line waveformSlowed upstroke

– AS– LV failure

• sharp vertical in hyperdynamic states

– Anemia– Hyperthermia– Hyperthyroidism– SNS– Aortic regurg

Age effect

arterial waveforms –differential iagnosis

.

Pulsus alternance Seen in:LVD/cardiomyopathies, HTN,AS,Normal hearts with SVT

pulsus bisfrenus is a sign of combined aortic valve lesion, also seen in hypertrophic obstructive cardiomyopathy (HOCM), patent ductus arteriosus, arteriovenous fistulas and normal hearts in a hyperdynamic state

hyperdynamic statesAR

ASLV failure

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COMPLICATIONS ARTERIAL LINE

• Thrombosis/embolus• Hematoma• Infection• Nerve damage/palsy

• Disconnect=blood loss• Fistula• Aneurysm• Digital ischemia

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LOSS OF WAVEFORM

•asystole• Stopcock• Monitor not on correct scale• Nonfunctioning monitor• Nonfunctioning transducer• Kinked/clotted catheter

Technical issues/resonance artifacts

resonance artifacts

DAMPENED WAVEFORM• Air bubble/blood in line• Clot• Disconnect/loose tubing• Underinflated pressure bag• Catheter tip against wall• Compliant tubing

UNDERDAMPED WAVEFORM

• Too many stopcocks• Long tubing• Air bubbles• Defective transducer

Arterial line dynamic response testing

Other functions of A-line

• Blood extraction• pulse rate and rhythm• effects of dysrhythmia

on perfusion• ECG lead disconnection• continuous cardiac

output using pulse contour analysis

• pulse pressure variation (suggests fluid responsiveness)

• steeper upstroke of pulse pressure = increased contractility

• area under upstroke = SV• steep down stroke = low SVR

classification of cardiac output monitoring systems.

INVASIVE-PAC LESS INVASIVE - PCM: pulse contour method - TPD :transpulmonary dilution - TED :trans esophageal Doppler NONINVASIVE - PCM - TTE/US - BIOEMPEDANCE,BIOREACTANCE - NICO

PULMONARY ARTERY CATHETER

Markings on catheter.1. Each thin line= 10 cm.2. Each thick line= 50 cm.

CVP Proximal (pressure line - injectate port for CO)-BLUE PA Distal (Pressure line hook up)- Yellow Extra port - usually- ClearThermistor – Red Cap

PA Catheter Timeline

Swan HJ, Ganz W, Forrester

J. NEJM.Aug

, 1970

Iberti TJ, Fischer EP, Leibowitz AB, et al. Pulmonary Artery

Catheter Study Group. JAMA. Dec, 1990

1970 19901980 2000 2005

Connors AF, et al. JAMA. Sept, 1996

1995

PA Catheters Are Good

PA Catheters Might be Bad

PA CathetersAre Bad

MDs AreIgnorant

Rhodes A. Int Care Med.

Feb, 2002

French PAC Study GroupJAMA. Nov, 2003

Founding of the Society of Critical Care Medicine

PACMAN, Escape, ARDSnet

2004 -2006

EBM

Overall Conclusion:1. No difference in LOS in the ICU2. No difference in Mortality3. No benefit, no harm• “There is no guided therapy tailored towards

PAC use.”• “PAC is a diagnostic tool, not a therapeutic

one

Advances-PCM• beat-to beat stroke volume analysis is based on the

Windkessel model, which was described by Otto Frank in 1899• In 1993 Wesseling et al described a method of using the finger

cuff arterial pressure wave to derive cardiac output“ Model Flow ” Currently the Nexfin

• In 1997 the first commercial system, the PiCCO (Pulsion, Munich, Germany) was released

• in 2002 the LiDCO-plus (and later rapid), (LiDCO Ltd., Cambridge, England)

• In 2004 the FloTrac-Vigileo, (Edwards Lifesciences, Irvine, CA, USA). Then volume view in 2010

Pulmonary Artery CatheterindicationsDiagnostic Diagnosis of shock states high- versus low-pressure pulmonary edema primary pulmonary hypertension valvular disease,

intracardiac shunts, cardiac tamponade, and pulmonary embolus (PE)

Monitoring complicated AMI hemodynamic instability after cardiac surgery Therapeutic - Aspiration of air emboli - local thromplytics

Contra-indications:• Tricuspid or pulmonary valve

mechanical prosthesis • Right heart mass (thrombus and/or

tumor) • Tricuspid or pulmonary valve

endocarditis

PAC parameters and NL values

Measured values• CVP: 2-6mmHg• PAWP: 8-12mmHg• PAP: 25/10mmHg• SvO2: 0.65-0.70• Temperature• Q: 4-8L/min• CI: 2.5-4L/min

Derived values – use of formula: Q = MAP-CVP/SVR• SV: 50-100mL/beat• SVI: 25-45mL/beat/m2• SVR: 900-1300

dynes-sec/cm5• SVRI: 1900-2400 dyne-

sec/cm5• PVR: 40-150 dyne-sec/cm5• PVRI: 120-200 dynes-sec/c

EQUATIONS

• Cardiac Output=Fick equation [VO2 = QT x (CaO2-CvO2)]

Change in pressure / total blood flow

Systemic Vascular Resistance Index =SVRI = (MAP ) = (MAP-CVP)(80)/CI Pulmonary Vascular Resistance Index = PVRI = (MPAP-PAOP)(80)/CI 80 converts mm Hg 80 converts mm Hg-min-m2/liters to dynes*sec/*cm-5

SVR: 900-1300 dynes-sec/cm5SVRI: 1900-2400 dyne-sec/cm5PVR: 40-150 dyne-sec/cm5PVRI: 120-200 dynes-sec/c

PAC WAVES

PAWP

How to measure the PAOP?

HOW TO LOCALIZE DURING SPONTANEOUS VENT.?

ALL PA measurements are calculated at end expiration because the lungs are at their most equal -(negative vs. positive pressures)

HOW TO LOCALIZE DURING MECH. VENT.?

PAW WAVEFORM WITH MECHANICAL VENTILATION

What is the abnormality?

What is the abnormality?

What is the abnormality?

Pericardial tamponade: high PCWP, high SVR, CVP = PCWP

Right heart failure: high CVP, low CI, high PVR

Complications of PAC• Venous access

complications - include arterial

puncture - hemothorax - Pneumothorax • Arrhythmias - PVCs or nonsustained

VT - Significant VT or

ventricular fibrillation

• Right bundle-branch block (RBBB)

• PA rupture • PAC related infection • Pulmonary infarction

SUGGESTED APPROACH TO PAC USE

• potentially useful in undifferentiated, multi-factorial shock states (for Q and ScVO2)

• useful in right heart pathology and pulmonary hypertension

• requires careful patient selection (including a contraindication assessment)

• don’t wedge (PADP can usually be used to estimate PAOP)• monitor for complications (predominantly on insertion)• remove after 72 hours

ARTERIAL WAVEFORM ANALYSIS TECNIQUES

other devicesPRAM: Pressure Recording Analytical Method

SD of 2000 arterialwaveform points

Statistical analysis of Arterial Pressure

Pulse Contour Parameters Pulse Contour Cardiac Output PCCO• Arterial Blood Pressure AP• Heart Rate HR• Stroke Volume ,CO SV• Stroke Volume Variation SVV• Pulse Pressure Variation PPV• Systemic Vascular Resistance SVR• Index of Left Ventricular Contractility dPmx*

MANY OTHER PARAMETERS AWAITING VALIDATION

Non invasive PCM

CALIBRATION FOR PCM Cardiac output is measured by another more accurate modality to

initially calibrate the PCA system and then for recalibration as needed

1-Transpulmonary Thermodilution Methods:• PiCCO (Pulsion Medical Systems&GE technology) • Volume View (Edwards Life Sciences) 2-Lithium Dilution Technique:• LiDCO /LiDCOplus/LiDCOrapid ( LiDCO limited) 3-Ultrasound Indicator Dilution :COstatus (Transonic

Systems, Inc.) Device that do not need calibration: -FLOTRAC/VIGILEO: estimate CO by the standard deviation of pulse

pressure sampled during a time window of 20 seconds -PRAM :estimate cardiac output using frequency of 1000 HZ

62

Transpulmonary thermodilution-PICCO and Edward / Volume View TM

• .

63

Advanced Thermodilution Curve Analysis

Transpulmonary thermodilution: Volumetric curve

Mtt: Mean Transit time time when half of the indicator has passed the point of detection in the artery

DSt: Down Slope time exponential downslope time of the thermodilution curve

For the calculations of volumes…

ln Tb

injectionrecirculation

MTtt

e-1

DSt

Tb

…and…

All volumetric parameters are obtained by advanced analysis of the thermodilution curve:

ITTV = CO * MTt PTV = CO * DSt

ITTV = CO * MTt

PTV = CO * DSt

ITBV = 1.25 * GEDV

EVLW* = ITTV - ITBV

GEDV = ITTV - PTV RAEDV RVEDV LAEDV LVEDV

RAEDV RVEDV LAEDV LVEDVPBV

RAEDV RVEDV LAEDV LVEDVPTV

PTV

EVLW*

EVLW*

Calculation of volumes

Transpulmonary thermodilution

monitors are not only

CO monitoring devices

Transpulmonary thermodilution

2- Global end-diastolic volume (GEDV)

1- Cardiac outputGEDVmarker of

cardiac preload

Extravascular lung water (EVLW)

• Normal – 3-7 mL/kg• Increased > 7 mL/kg• Pulmonary edema > 10

mL/kg

.

Pulmonarv Blood Volume

Hydrostaticpulmonary edema

Permeabilitypulmonary edema

PVPI =PBV

EVLW*normal

elevated

elevated

PVPI* =PBVEVLW*

elevated

elevated

normal

PVPI=PBV

EVLW*normal

normal

normal

PBV

PBV

PBV Normal Lung

Extra Vascular Lung Water

Pulmonary Vascular Permeability Index-PVPI

• It allows to identify the type of pulmonary oedema

PARAMETERS Definitions• LVSWI = SVI × (MAP – PAOP) × 0.0136• CP = MAP × CO/451• ITTV = CO × MTt• PTV = CO × DSt• GEDV = ITTV - PTV = CO × (MTt - DSt)• ITBV = 1.25 × GEDV• CFI = (CO/GEDV) × 103• GEF = SV/(GEDV/4)• EVLW = ITTV - ITBV• PVPI = EVLW/PBV

Normal rangesPARAMETER RANGE UNIT

CI 3.0 – 5.0l/min/m2

SVI 40 – 60ml/m2

GEDI 680 – 800ml/m2

ITBI 850 – 1000ml/m2

ELWI* 3.0 – 7.0ml/kg

PVPI* 1.0 – 3.0 SVV 10

% PPV 10

% GEF 25 – 35

% CFI 4.5 – 6.5

1/min MAP 70 – 90

mmHg

SVRI 1700 – 2400 dyn*s*cm-5*m

71

Transpulmonary thermodilution

2- Global end-diastolic volume (GEDV)

4- Extravascular lung water (EVLW)

1- Cardiac output

3- Cardiac function index (CFI)

5- Pulmonary vascular permeability index

Pulse contour analysis1- Continuous cardiac output (CCO)

2- Stroke volume variation (SVV)

3- Pulse pressure variation (PPV)

ScvO2

Complete picture

of the patient’s

hemodynamic status

Clinical application

What is the current situation?.………..……..………….Cardiac Output!

What is the preload?.……………….....…Global End-Diastolic Volume!

What is the afterload?……………..…..Systemic Vascular Resistance!

What about the contractility?........................ dPmx* LV pressure velocity

What about the Perfusion ?............................central venous saturation

Will volume increase CO?...fluid response….Stroke Volume Variation!

Are the lungs still dry?...…….……...…..….Extravascular Lung Water!*

pulmonary vascular permeability index… Dx of p.edema

hypovolemia vascular tone depression

myocardial depression

vasopressors inotropesfluids

presence of associated lung injury

Hemodynamic failure in critically ill patients: 3 components

Myocardial depression

inotropes

+ CFI (PiCCO)

Echocardiography

Hemodynamic failure in critically ill patients: 3 components

vascular tone depression

vasopressors

Arterial catheter (DAP ++)

Hemodynamic failure in critically ill patients: 3 components

hypovolemia

fluids

Prediction of fluid responsiveness

• PPV, SVV • PLR or end-expiratory occlusion test

if SB, arrhythmias, low TV or low lung compliance

Evaluation: real-time CO

Lung tolerance

PAOP EVLW

presence of associated lung injury

Hemodynamic failure in critically ill patients: 3 components

First, try to perform echocardiography to assess cardiac function

Normal cardiac fonction

Lung injury ?ABG, Chest X-ray

Abnormal cardiac function

no yes

CVCCVP

SvcO2

Art cath

AP PPV

PiCCO

COGEDV, EVLW, CFI

PPV, SVVScvO2

Basic monitoring

+

advancedmonitoringyes

considered valid?

no

only

Patient with circulatory failure

VolumeViewPAC

COPAOP

RAP, PAPSvO2

Which measurement is most reliable for predicting fluid responsiveness in a patient with septic shock requiring mechanical ventilation? Pick one best answer• A. Central venous pressure (CVP)• B. Pulmonary artery occlusion pressure (PAOP)• C. Pulse pressure variation (ΔPP)• D. Mixed venous oxygen saturation (SvO2)

vpw

• measured by 1, dropping a perpendicular line from the point at which the left subclavian artery exists the aortic arch and 2, measuring across to the point at which the superior vena cava crosses the right mainstem bronchus.

71 mm and 62 mm for supine and erect CRs, respectively.