Haemodynamic Monitoring Theory and Practice

2 Haemodynamic Monitoring A.Physiological Background B.Monitoring C.Optimising the Cardiac Output D.Measuring Preload E.Introduction to PiCCO Technology F.Practical Approach G.Fields of Application H.Limitations

E. Introduction to PiCCO Technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular lung water 7.Pulmonary permeability Haemodynamic Monitoring

PiCCO Technology Parameters for guiding volume therapy Introduction to the PiCCO-Technology CO Volumetric preload EVLW Contractility Differentiated Volume Management - static - dynamic

PiCCO Technology is a combination of transpulmonary thermodilution and pulse contour analysis Principles of Measurement Left Heart Right Heart Pulmonary Circulation Lungs Body Circulation PULSIOCATH CVC PULSIOCATH arterial thermodilution catheter central venous bolus injection Introduction to the PiCCO-Technology – Function

Bolus injection concentration changes over time (Thermodilution curve) After central venous injection the cold bolus sequentially passes through the various intrathoracic compartments The temperature change over time is registered by a sensor at the tip of the arterial catheter Introduction to the PiCCO-Technology – Function Left heartRight heart Lungs RARVLALVPBV EVLW Principles of Measurement

Intrathoracic Compartments (mixing chambers) Introduction to the PiCCO-Technology – Function Pulmonary Thermal Volume (PTV) Intrathoracic Thermal Volume (ITTV) Total of mixing chambers RA RVLALVPBV EVLW Largest single mixing chamber

Haemodynamic Monitoring E. Introduction to PiCCO Technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

T b x dt (T b - T i ) x V i x K TbTb Injection t ∫  = CO TD a T b = Blood temperature T i = Injectate temperature V i = Injectate volume ∫ ∆ T b. dt = Area under the thermodilution curve K = Correction constant, made up of specific weight and specific heat of blood and injectate The CO is calculated by analysis of the thermodilution curve using the modified Stewart-Hamilton algorithm Calculation of the Cardiac Output Introduction to the PiCCO-Technology – Thermodilution

The area under the thermodilution curve is inversely proportional to the CO. 36, Thermodilution curves Normal CO: 5.5l/min Introduction to the PiCCO-Technology – Thermodilution 36, ,5 37 Time low CO: 1.9l/min High CO: 19l/min Time Temperature

Transpulmonary vs. Pulmonary Artery Thermodilution Left heart Right Heart Pulmonary Circulation Lungs Body Circulation PULSIOCATH arterial thermo- dilution catheter central venous bolus injection RA RV PA LA LV Aorta Transpulmonary TD (PiCCO)Pulmonary Artery TD (PAC) In both procedures only part of the injected indicator passes the thermistor. Nonetheless the determination of CO is correct, as it is not the amount of the detected indicator but the difference in temperature over time that is relevant! Introduction to the PiCCO –Technology – Thermodilution

Comparison with the Fick Method 0,97 0,68 ± 0,6237/449 Sakka SG et al., Intensive Care Med 25, / - 0,19 ± 0,219/27 McLuckie A. et a., Acta Paediatr 85, ,96 0,16 ± 0,3130/150 Gödje O et al., Chest 113 (4), ,32 ± 0,2923/218 Holm C et al., Burns 27, ,93 0,13 ± 0,5260/180 Della Rocca G et al., Eur J Anaest 14, ,95 -0,04 ± 0,4117/102 Friedman Z et al., Eur J Anaest, ,95 0,49 ± 0,4545/283 Bindels AJGH et al., Crit Care 4, ,98 0,03 ± 0,1718/54 Pauli C. et al., Intensive Care Med 28, /120 n (Pts / Measurements) 0,99 0,03 ± 0,24 Tibby S. et al., Intensive Care Med 23, 1997 r bias ±SD(l/min) Comparison with Pulmonary Artery Thermodilution Validation of the Transpulmonary Thermodilution Introduction to the PiCCO –Technology – Thermodilution

MTt: Mean Transit time the mean time required for the indicator to reach the detection point DSt: Down Slope time the exponential downslope time of the thermodilution curve Recirculation t e -1 Tb From the characteristics of the thermodilution curve it is possible to determine certain time parameters Extended analysis of the thermodilution curve Introduction to the PiCCO-Technology – Thermodilution Injection In Tb MTtDSt T b = blood temperature; lnTb = logarithmic blood temperature; t = time

Pulmonary Thermal Volume PTV = Dst x CO By using the time parameters from the thermodilution curve and the CO ITTV and PTV can be calculated Calculation of ITTV and PTV Introduction to the PiCCO-Technology – Thermodilution Recirculation t e -1 Tb Injection In Tb Intrathoracic Thermal Volume ITTV = MTt x CO MTtDSt

Pulmonary Thermal Volume (PTV) Intrathoracic Thermal Volume (ITTV) Calculation of ITTV and PTV Einführung in die PiCCO-Technologie – Thermodilution ITTV = MTt x CO PTV = Dst x CO RA RVLALVPBV EVLW

GEDV is the difference between intrathoracic and pulmonary thermal volumes Global End-diastolic Volume (GEDV) Volumetric preload parameters – GEDV RA RVLALVPBV EVLW ITTV GEDV PTV Introduction to the PiCCO –Technology – Thermodilution

Volumetric preload parameters – ITBV Intrathoracic Blood Volume (ITBV) GEDV ITBV PBV RA RVLALVPBV EVLW Introduction to the PiCCO –Technology – Thermodilution ITBV is the total of the Global End-Diastolic Volume and the blood volume in the pulmonary vessels (PBV)

ITBV TD (ml) ITBV = 1.25 * GEDV – 28.4 [ml] GEDV vs. ITBV in 57 Intensive Care Patients I ntra t horacic B lood V olume ( ITBV ) Volumetric preload parameters – ITBV Introduction to the PiCCO-Technology – Thermodilution ITBV is calculated from the GEDV by the PiCCO Technology GEDV (ml) Sakka et al, Intensive Care Med 26: , 2000

Summary and Key Points - Thermodilution PiCCO Technology is a less invasive method for monitoring the volume status and cardiovascular function. Transpulmonary thermodilution allows calculation of various volumetric parameters. The CO is calculated from the shape of the thermodilution curve. The volumetric parameters of cardiac preload can be calculated through advanced analysis of the thermodilution curve. For the thermodilution measurement only a fraction of the total injected indicator needs to pass the detection site, as it is only the change in temperature over time that is relevant. Introduction to the PiCCO-Technology

Haemodynamic Monitoring E. Introduction to PiCCO Technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

Transpulmonary Thermodilution The pulse contour analysis is calibrated through the transpulmonary thermodilution and is a beat to beat real time analysis of the arterial pressure curve Calibration of the Pulse Contour Analysis Introduction to the PiCCO-Technology – Pulse contour analysis Injection Pulse Contour Analysis T = blood temperature t = time P = blood pressure CO TPD CO TPD = SV TD HR

PCCO = cal HR   P(t) SVR + C(p) dP dt ( ) Cardiac Output Patient- specific calibration factor (determined by thermodilution) Heart rate Area under the pressure curve Shape of the pressure curve Aortic compliance Systole Introduction to the PiCCO-Technology – Pulse contour analysis Parameters of Pulse Contour Analysis

n (Pts / Measurements) 0,940,03 ± 0,6312 / 36Buhre W et al., J Cardiothorac Vasc Anesth 13 (4), / / / / / / 96- / --0,40 ± 1,3Mielck et al., J Cardiothorac Vasc Anesth 17 (2), ,880,31 ± 1,25Zöllner C et al., J Cardiothorac Vasc Anesth 14 (2), ,88-0,2 ± 1,15Gödje O et al., Crit Care Med 30 (1), ,94-0,02 ± 0,74Della Rocca G et al., Br J Anaesth 88 (3), ,93-0,14 ± 0,33Felbinger TW et al., J Clin Anesth 46, / - 0,14 ± 0,58Rauch H et al., Acta Anaesth Scand 46, 2002 r bias ±SD (l/min) Comparison with pulmonary artery thermodilution Validation of Pulse Contour Analysis Introduction to the PiCCO-Technology – Pulse contour analysis

SV max – SV min SVV = SV mean SV max SV min SV mean The Stroke Volume Variation is the variation in stroke volume over the ventilatory cycle, measured over the previous 30 second period. Parameters of Pulse Contour Analysis Introduction to the PiCCO-Technology – Pulse Contour Analysis Dynamic parameters of volume responsiveness – Stroke Volume Variation

PP max – PP min PPV = PP mean The pulse pressure variation is the variation in pulse pressure over the ventilatory cycle, measured over the previous 30 second period. Parameters of Pulse Contour Analysis Introduction to the PiCCO-Technology – Pulse Contour Analysis Dynamic parameters of volume responsiveness – Pulse Pressure Variation PP max PP mean PP min

Summary pulse contour analysis - CO and volume responsiveness The PiCCO technology pulse contour analysis is calibrated by transpulmonary thermodilution PiCCO technology analyses the arterial pressure curve beat by beat thereby providing real time parameters Besides cardiac output, the dynamic parameters of volume responsiveness SVV (stroke volume variation) and PPV (pulse pressure variation) are determined continuously Introduction to the PiCCO-Technology – Pulse contour analysis

Haemodynamic Monitoring E. Introduction to PiCCO Technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

Contractility is a measure for the performance of the heart muscle Contractility parameters of PiCCO technology: - dPmx (maximum rate of the increase in pressure) - GEF (Global Ejection Fraction) - CFI (Cardiac Function Index) Contractility Introduction to the PiCCO-Technology – Contractility parameters kg

Contractility parameter from the pulse contour analysis Introduction to the PiCCO-Technology – Contractility parameters dPmx = maximum velocity of pressure increase The contractility parameter dPmx represents the maximum velocity of left ventricular pressure increase.

Contractility parameter from the pulse contour analysis Introduction to the PiCCO-Technology – Contractility parameters femoral dP/max [mmHg/s] LV dP/dtmax [mmHg/s] dPmx was shown to correlate well with direct measurement of velocity of left ventricular pressure increase in 70 cardiac surgery patients de Hert et al., JCardioThor&VascAnes 2006 n = 220 y = (0,8* x) r = 0,82 p < 0, dPmx = maximum velocity of pressure increase

is calculated as 4 times the stroke volume divided by the global end-diastolic volume reflects both left and right ventricular contractility GEF = Global Ejection Fraction Contractility parameters from the thermodilution measurement Introduction to the PiCCO-Technology – Contractility parameters 4 x SV GEF = GEDV LA LVRA RV

Combes et al, Intensive Care Med 30, 2004 GEF = Global Ejection Fraction Comparison of the GEF with the gold standard TEE measured contractility in patients without right heart failure sensitivity 0 0,4 0,6 0, ,2 0,40,60,8 1 specifity  FAC, %  GEF, % r=076, p<0,0001 n=47 Introduction to the PiCCO-Technology – Contractility parameters Contractility parameters from the thermodilution measurement

is the CI divided by global end-diastolic volume index is - similar to the GEF – a parameter of both left and right ventricular contractility CFI = Cardiac Function Index CI CFI = GEDVI Introduction to the PiCCO-Technology – Contractility parameters Contractility parameters from the thermodilution measurement

Combes et al, Intensive Care Med 30, 2004 sensitivity 0 0,4 0,6 0, ,2 0,40,60,8 1 specificity ,5 3 2  FAC, %  GEF, % r=079, p<0,0001 n=47 CFI = Cardiac Function Index Introduction to the PiCCO-Technology – Contractility parameters CFI was compared to the gold standard TEE measured contractility in patients without right heart failure Contractility parameters from the thermodilution measurement

Haemodynamic Monitoring E. Introduction to PiCCO technology 1.Functions 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

is calculated as the difference between MAP and CVP divided by CO as an afterload parameter it represents a further determinant of the cardiovascular situation is an important parameter for controlling volume and catecholamine therapies (MAP – CVP) x 80 SVR = CO Afterload parameter SVR = Systemic Vascular Resistance MAP = Mean Arterial Pressure CVP = Central Venous Pressure CO = Cardiac Output 80 = Factor for correction of units Introduction to the PiCCO –Technology – Afterload parameter

The parameter dPmx from the pulse contour analysis as a measure of the left ventricular myocardial contractility gives important information regarding cardiac function and therapy guidance The contractility parameters GEF and CFI are important parameters for assessing the global systolic function and supporting the early diagnosis of myocardial insufficiency The Systemic Vascular Resistance SVR calculated from blood pressure and cardiac output is a further parameter of the cardiovascular situation, and gives additional information for controlling volume and catecholamine therapies Summary and Key Points Introduction to the PiCCO –Technology – Contractility and Afterload

Haemodynamic Monitoring E. Introduction to PiCCO technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

ITTV – ITBV = EVLW The Extravascular Lung Water is the difference between the intrathoracic thermal volume and the intrathoracic blood volume. It represents the amount of water in the lungs outside the blood vessels. Calculation of Extravascular Lung Water (EVLW) Introduction to the PiCCO –Technology – Extravascular Lung Water

Katzenelson et al,Crit Care Med 32 (7), 2004 Sakka et al, Intensive Care Med 26: , 2000 GravimetryDye dilution EVLW from the PiCCO technology has been shown to have a good correlation with the measurement of extravascular lung water via the gravimetry and dye dilution reference methods Validation of Extravascular Lung Water n = 209 r = 0.96 ELWI by gravimetry ELWI by PiCCO R = 0,97 P < 0,001 Y = 1.03x ELWI TD (ml/kg) ELWI ST (ml/kg) Introduction to the PiCCO –Technology – Extravascular Lung Water

Boeck J, J Surg Res 1990; High extravascular lung water is not reliably identified by blood gas analysis EVLW as a quantifier of lung edema PaO 2 /FiO ELWI (ml/kg) Introduction to the PiCCO –Technology – Extravascular Lung Water

ELWI = 7 ml/kg ELWI = 8 ml/kg ELWI = 14 ml/kg ELWI = 19 ml/kg Extravascular lung water index (ELWI) normal range: 3 – 7 ml/kg Pulmonary oedema Normal range EVLW as a quantifier of lung oedema Introduction to the PiCCO –Technology – Extravascular Lung Water

40 Halperin et al, 1985, Chest 88: 649 Chest x ray – does not reliably quantify pulmonary oedema and is difficult to judge, particularly in critically ill patients r = 0.1 p >  radiographic score  ELWI EVLW as a quantifier of lung oedema Introduction to the PiCCO –Technology – Extravascular Lung Water

ELWI (ml/kg) > 21 n = n = n = 174 < 7 n = 45 Mortality(% ) n = 373*p = Sturm J in: Lewis, Pfeiffer (eds): Practical Applications of Fiberoptics in Critical Care Monitoring, Springer Verlag Berlin - Heidelberg - NewYork 1990, pp Relevance of EVLW Assessment The amount of extravascular lung water is a predictor for mortality in the intensive care patient ELWI (ml/kg) Mortality (%) 20 n = > Sakka et al, Chest 2002 Introduction to the PiCCO –Technology – Extravascular Lung Water

Intensive Care days Mitchell et al, Am Rev Resp Dis 145: , 1992 Relevance of EVLW Assessment Volume management guided by EVLW can significantly reduce time on ventilation and ICU length of stay in critically ill patients, when compared to PCWP oriented therapy, Ventilation Days PAC Group n = 101 * p ≤ 0,05 PAC GroupEVLW Group 22 days15 days9 days7 days * p ≤ 0,05 Introduction to the PiCCO –Technology – Extravascular Lung Water

Haemodynamic Monitoring E. Introduction to PiCCO Technology 1.Principles of function 2.Thermodilution 3.Pulse contour analysis 4.Contractility parameters 5.Afterload parameters 6.Extravascular Lung Water 7.Pulmonary Permeability

Differentiating Lung Oedema PVPI = Pulmonary Vascular Permeability Index is the ratio of Extravascular Lung Water to Pulmonary Blood Volume is a measure of the permeability of the lung vessels and as such can classify the type of lung oedema (hydrostatic vs. permeability caused) EVLW PVPI = PBV EVLW Introduction to PiCCO Technology – Pulmonary Permeability

permeability PVPI normal (1-3) PVPI raised (>3) Classification of Lung Oedema with the PVPI Difference between the PVPI with hydrostatic and permeability lung oedema: Lung oedema hydrostatic PBV EVLW PBV EVLW PBV EVLW PBV EVLW Introduction to PiCCO Technology – Pulmonary Permeability

16 patients with congestive heart failure and acquired pneumonia. In both groups EVLW was 16 ml/kg. Validation of the PVPI PVPI can differentiate between a pneumonia caused and a cardiac failure caused lung oedema. Benedikz et al ESICM 2003, Abstract 60 Cardiac insufficiency PVPI Pneumonia Introduction to PiCCO Technology – Pulmonary Permeability

EVLWI answers the question: Clinical Relevance of the Pulmonary Vascular Permeability Index PVPI answers the question: and can therefore give valuable aid for therapy guidance! How much water is in the lungs? Why is it there? Introduction to PiCCO Technology – Pulmonary Permeability

Summary and Key Points EVLW as a valid measure for the extravascular water content of the lungs is the only parameter for quantifying lung oedema available at the bedside. Blood gas analysis and chest x-ray do not reliably detect and measure lung edema EVLW is a predictor for mortality in intensive care patients The Pulmonary Vascular Permeability Index can differentiate between hydrostatic and a permeability caused lung oedema Introduction to PiCCO Technology – EVLW and Pulmonary Permeability