Advances in haemodynamic monitoring

Anaesthesia monitoring

Published in: Health & Medicine

Advances in haemodynamic monitoring from Mohamed Abdulrazik

 Transcript

• 1. AdvAnces in HemodynAmicAdvAnces in HemodynAmic monitoringmonitoring ByBy moHAmed A. AlimoHAmed A. Ali security Forces HospitAl mAKKAHsecurity Forces HospitAl mAKKAH
• 2. introduction • Hemodynamics is concerned with the forces generated by the heart and the resulting motion of blood through the cardiovascular system. • Hemodynamic monitoring is the intermittent or continuous observation of physiological parameters related to the circulatory system that lead to early detection of the need for therapeutic interventions.
• 3. - Intravascular volume 2-Myocardial contraction 3- heart rate 4- Vasoactivity
• 4. old equipments 1. ArteriAl line 1. Real time SBP, DBP, MAP 2. Pulse pressure variation (∆PP) • ΔPP (%) = Respiratory-induced pulse pressure variations obtained with an arterial line which indicate fluid responsiveness in mechanically ventilated patients
• 5. • AdvAntAgeAdvAntAge – Easy setup – Real time BP monitoring – Beat to beat waveform display – Allow regular sampling of blood for lab tests • disAdvAntAgesdisAdvAntAges – Invasive – Risk of haematoma, distal ischemia, pseudoaneurysm formation and infection
• 6. 2. centrAl venous cAtHeter2. centrAl venous cAtHeter – Measurement of CVP, medications infusion and modified form allow for dialysis •AdvAntAgesAdvAntAges – Easy setup – Good for medications infusion •disAdvAntAgesdisAdvAntAges – Cannot reflect actual RAP in most situations – Multiple complications •Infections, thrombosis, complications on insertion, vascular erosion and bleeding
• 7. limitAtion oF cvp Systemic venoconstriction Decrease right ventricular compliance Obstruction of the great veins Tricuspid regurgitation Mechanical ventilation
• 8. 3. pulmonAry ArteriAl3. pulmonAry ArteriAl cAtHetercAtHeter
• 9. indicAtions For pApindicAtions For pAp monitoringmonitoring 1. Shock of all types 2. Assessment of cardiovascular function and response to therapy 3. Assessment of pulmonary status 4. Assessment of fluid requirement 5. Perioperative monitoring
• 10. clinicAl ApplicAtions oFclinicAl ApplicAtions oF pAcpAc PAC can generate large numbers of haemodynamic variables BAsic pArAmeters • Central venous pressure (CVP) • Pulmonary artery pressure (PAP) • Pulmonary arterial occlusion pressure (PAOP) • Cardiac output (CO) derived pArAmeters • cardiac index (CI) • Stroke volume (SV) • Rt ventricle ejection fraction/ end diastolic volume (RVEF / RVEDV) • Systemic vascular resistance index (SVRI) • Pulmonary vascular resistance index (PVRI) • Oxygen delivery / uptake (DO2 / VO2)
• 11. cArdiogenic • High CVP • Low CI • High SVRI [[ ⇒ Consider inotropes / IABP vAsogenic • Low CVP • High CI • Low SVRI ⇒ Consider vasopressor pAtient witHpAtient witH HypotensionHypotension Hypovolemic •Low CVP •Low CI •High SVRI ⇒ Consider fluid challenge
• 12. mixed venousmixed venous sAturAtion (svo2)sAturAtion (svo2) • Measured in pulmonary artery blood • Marker of the balance between whole body O2 delivery (DO2) and O2 consumption (VO2) • VO2 = DO2 * (SaO2 – SvO2) • In fact, DO2 is determined by CO, Hb and SaO2. Therefore, SvO2 affected by – CO – Hb – Arterial oxygen saturation – Tissue oxygen consumption

• 13. • normAl svo2 = 70-75%normAl svo2 = 70-75% decreAsed svo2decreAsed svo2 • Increased consumption • Pain, Hyperthermia • Decreased delivery • Low CO • Anemia • Hypoxia increAsed svo2increAsed svo2 • Increased delivery • High CO • Hyperbaric O2 • Low consumption • Sedation • Paralysis • Cyanide toxicity
• 14. • AdvAntAgesAdvAntAges – Provide lot of important haemodynamic parameters – Sampling site for SvO2 • disAdvAntAgesdisAdvAntAges – Costly – Invasive – Multiple complications (eg. arrhythmia, catheter looping, balloon rupture, PA injury, pulmonary infarction)
• 15. AdvAnce in hAemodynAmicAdvAnce in hAemodynAmic AssessmentAssessment 1. Modification of old equipment 2. Echocardiogram and esophageal doppler 3. Pulse contour analysis and transpulmonary thermodilution 4. Partial carbon dioxide rebreathing with application of Fick principle 5. Electrical bioimpedance
• 16. truCCOMS system Real Time Continuous Cardiac Output Monitoring System
• 17. • As CO increase, blood flow over the heat transfer device increase and the device require more power to keep the temp. difference Therefore provide continuous CO data
• 18. • AdvAntAgeAdvAntAge – Continuous CO monitoring – Provision of important haemodynamic parameter as PAC • disAdvAntAgedisAdvAntAge – Invasive – Costly – Complications associated with PAC use
• 19. echo • Assessment of cardiac structure, ejection fraction and cardiac output • Based on 2D and doppler flow technique EF (%) = [(EDV - ESV) / EDV] x 100
• 20. echo dopplerecho doppler ultrAsoundultrAsound• Measure blood flow velocity in heart and great vessels • Based on Doppler effect ⇒ “ Sound freq. increases as sound source moves toward the observer and decreases as the sound moves away”
• 21. trAnsthorAcic echotrAnsthorAcic echo • AdvAntAges – Fast to perform – Non invasive – Can assess valvular structure and myocardial function – No added equipment needed • disAdvAntAges – Difficult to get good view (esp. whose on ventilator / obese) – Cannot provide continuous monitoring
• 22. esophAgeAl Aortic doppleresophAgeAl Aortic doppler usus • Doppler assessment of decending aortic flow • CO is determined by measuring aortic blood flow assuming a constant partition between caudal and cephalic blood supply areas • Probe is smaller than that of TEE • Correlate well with CO measured by thermodilution Decending aorta
• 23. • AdvAntAgesAdvAntAges – Easy placement, minimal training needed (~ 12 cases) – Provide continuous,real-time monitoring – Low incidence of iatrogenic complications – Minimal infective risk • disAdvAntAgesdisAdvAntAges – High cost – Poor tolerance at awake patient, so it’s used for those intubated – Probedisplacement can occur during prolonged monitoring and patient’s turning – High inter-observer variability when measuring changes in SV in response to fluid challenges
• 24. pulse contourpulse contour AnAlysisAnAlysis• Arterial pressure waveform is determined by interaction of stroke volume and SVR
• 25. pulse contourpulse contour AnAlysisAnAlysis • PiCCOPiCCO and LiDCOLiDCO are the two commonly used model on basis of PCA • PCA involves the use of an arterially placed catheter with a pressure transducer, which can measure pressure tracings on a beat-to-beat basis
• 26. TheThe PiCCOPiCCO Technology uses any standard CV-lineTechnology uses any standard CV-line without the need for Rt. Heart catheter (PAC) and awithout the need for Rt. Heart catheter (PAC) and a thermistor-tipped arterialthermistor-tipped arterial PiCCOPiCCO catheter instead of thecatheter instead of the standard arterial line.standard arterial line. how does the phow does the piicco-technology work?cco-technology work? pArAmeters meAsured with the picco-technologypArAmeters meAsured with the picco-technology thermodilution pArAmetersthermodilution pArAmeters • Cardiac Output CO • Global End-Diastolic Volume GEDV • Intrathoracic Blood Volume ITBV • Extravascular Lung Water EVLW •Cardiac Function Index CFI • Global Ejection Fraction GEF • Pulmonary Vascular Permeability Index PVPI* pulse contour pArAmeterspulse contour pArAmeters • Pulse Contour Cardiac Output PCCO • Arterial Blood Pressure AP • Heart Rate HR • Stroke Volume SV • Stroke Volume Variation SVV • Pulse Pressure Variation PPV • Systemic Vascular Resistance SVR • Index of Left Ventricular Contractility dPmx*
• 27. CV A B F R picco cAtheterpicco cAtheter 1. centrAl venous line (cv) 2. pulsiocAth thermodilution cAtheter with lumen for arterial pressure measurement Axillary: 4F (1,4mm) 8cm Brachial: 4F (1,4mm) 22cm Femoral: 3-5F (0,9-1,7mm) 7-20cm Radial: 4F (1,4mm) 50cm No Right Heart Catheter !
• 28. Bolus Injecti on Lungs PiCCO Catheter e.g. in femoral artery Transpulm. Thermodilution measurement only requires Central Venous Injection of a cold saline either at •(< 8°C) •(< 24°C) Room Temp. ThermodiluTion parameTersThermodiluTion parameTers Left HeartRight Heart RA PBV EVLW LA LV EVLW RV
• 29. Tb Injection Time ∫ ⋅∆ ⋅⋅− = dtT KV)T(T CO b iib TDa CardiaC ouTpuTCardiaC ouTpuT Tb = Blood temperature Ti = Injectate temperature Vi = Injectate volume ∫ ∆ Tb . dt = Area under the thermodilution curve K = Correction constant, made up of specific weight and specific heat of blood and injectate CO Calculation:  Area under the Thermodilution Curve •After central venous injection of the indicator, the thermistor at the tip of the arterial catheter measures the downstream temperature changes. •Cardiac output is calculated by analysis of the thermodilution curve using a modifiedmodified Stewart-Hamilton algorithm:Stewart-Hamilton algorithm:
• 30. Advanced Thermodilution CurveAdvanced Thermodilution Curve AnalysisAnalysis VolumeTriC parameTersVolumeTriC parameTers 1.1. MTt: Mean TransitMTt: Mean Transit time :time : • Time when half of the indicator has passed the point of detection in the artery 2.2. DSt: Down SlopeDSt: Down Slope time :time : • Exponential downslope time of the thermodilution curve For the calculations of volumes injection recirculation MTt t DSt All volumetric parameters are obtained by advanced analysis of the Thermodilution Curve:Thermodilution Curve:
• 31. RAEDV Thermodilution curve measured with arterial catheter CV Bolus Injection LAEDV LVEDVRVEDV Lungs afTer injeCTion, The indiCaTor passes The followingafTer injeCTion, The indiCaTor passes The following inTraThoraCiC ComparTmenTs:inTraThoraCiC ComparTmenTs: • The intrathoracic compartments can be considered as a series of “mixing chambers” for the distribution of the injected indicator (intrathoracic thermal volume). • The largest mixing chamber in this series are the lungs, here the indicator (cold) has its largest distribution volume (largest thermal volume). Intra thoracic Thermal VolumeIntra thoracic Thermal Volume (ITTV)(ITTV)PulmonaryPulmonary Thermal VolumeThermal Volume (PTV)(PTV) PBV EVLW EVLW
• 32. ITTV = CO * MTtTDa PTV = CO * DStTDa 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* Volume CalCulaTionsVolume CalCulaTions
• 33. pulmonary VasCular permeabiliTy indexpulmonary VasCular permeabiliTy index Pulmonary Vascular Permeability Index (PVPI*) is the ratio of Extravascular Lung Water (EVLW*) to pulmonary blood volume (PBV). It allows to identify the type of pulmonary oedema. Pulmonarv Blood Volume Hydrostatic Pulmonary Odema Permeability pulmonary edema PVPI = PBV EVL W Norma l Elevat e d Elevate d  PVPI = PBV EVL WElevat e d Elevated Norma l PVPI = PBV EVL WNorma l Norma l Norma l  PBV PBV PBV Norma Lun g Extra Vascular Lung Water
• 34. Global Ejection Fraction (GEF) (Transpulmonary Thermodilution) GEF = GED V 4 x SV RVEF = RVEDV SV LVEF = LVEDV SV RV ejection fraction (RVEF) (Pulm. Artery Thermodilution) LV ejection fraction (LVEF) (Echocardiography) 1 2&  3 global ejeCTion fraCTion Right Heart Left Heart Lungs RAED V RVED V LVED V Stroke Volume SV LAED V • Ejection Fraction: Stroke Volume related to End-Diastolic Volume PBV EVL W EVL W

• 35. index of lefT VenTriCular ConTraCTiliTy t [s] P [mm Hg] • dPmx* -- It represents left ventricular pressure velocity increasedPmx* -- It represents left ventricular pressure velocity increase and thus is a parameter ofand thus is a parameter of myocardial contractilitymyocardial contractility dtmax of arterial pressuredtmax of arterial pressure ccurveurve dPdP dPmx*dPmx* ==
• 36. SVSVmaxmax SVSVminmin SVSVmeanmean SVSVmaxmax – SV– SVminmin SVV =SVV = SVSVmeanmean sTroke Volume VariaTionsTroke Volume VariaTion • Stroke Volume Variation (SVV) represents the variation of stroke volume (SV) over the ventilatory cycle. • SVV is... 1- measured over last 30s window 2- only applicable in controlled mechanically ventilated patients with regular heart rhythm
• 37. pulse pressure VariaTionpulse pressure VariaTion PPPPmaxmax – PP– PPminmin PPV =PPV = PPPPmeanmean PPPPmaxmax PPPPmeanmean PPPPminmin • Pulse pressure variation (PPV) represents the variation of the pulse pressure over the ventilatory cycle. • PPV is... 1- measured over last 30s window 2- only applicable in controlled mechanically ventilated patients with regular heart rhythm
• 38. sVV and ppV – CliniCal sTudiessVV and ppV – CliniCal sTudies Sensitivity Specificity • Central Venous Pressure (CVP) can not predict whether volume load leads to an increase in stroke volume or not. - - - CVP __ SVV 1 0,2 0,4 0,6 0,8 1 0,50 0 •SVV and PPV are excellent predictors of volume responsiveness.
• 39. Drugs Volume What is the current situation?.………..…....…..………….Cardiac Output! What is the preload?.……………….....….Global End-Diastolic Volume! Will volume increase CO?....………...….…….Stroke Volume Variation! CliniCal appliCaTion
• 40. • Global End-Diastolic Volume, GEDV and Intrathoracic Blood Volume (ITBV): have shown to be far more sensitive and specific to cardiac preload compared to the standard cardiac filling pressures CVP + PCWP as well as right ventricular enddiastolic volume. • The striking advantage of GEDV and ITBV is that they are not adversely influenced by mechanical ventilation • Extravascular Lung Water, EVLW* has shown to have a clear correlation to severity of ARDS, length of ventilation days, ICU-Stay and Mortality and is superior to assessment of lung odema by chest x-ray and clearly indicates fluid overload signifiCanCesignifiCanCe
• 41. normal rangesnormal ranges ParameterParameter RangeRange UnitUnit  CI 3.0 – 5.0 l/min/m2  SVI 40 – 60 ml/m2  GEDI 680 – 800 ml/m2  ITBI 850 – 1000 ml/m2  ELWI 3.0 – 7.0 ml/kg  PVPI 1.0 – 3.0 ml/kg  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
• 42. Decision tree for hemoDynamic / volumetric monitoring CI (l/min/m2 ) GEDI (ml/m2 ) or ITBI (ml/m2 ) ELWI* (ml/kg) (slowly responding) >3.0<3.0 >700 >850 <700 <850 >700 >850 <700 <850 ELWI* (ml/kg) GEDI (ml/m2 ) or ITBI (ml/m2 ) CFI (1/min) or GEF (%) <10 >10 <10 <10 <10>10 >10 >10 V+ V+! V+!V+Cat Cat OK! V- >700 >850 700-800 850-1000 >4.5 >25 >5.5 >30 >4.5 >25 700-800 850-1000 Cat >5.5 >30 >700 >850 700-800 850-1000 700-800 850-1000 ≤10 ≤10 ≤10 ≤10 V- V+ = volume loading (! = cautiously)V- = volume contractionCat = catecholamine / cardiovascular agen ** SVV only applicable in ventilated patients without cardiac arrhythmia >700 >850 <10Optimise to SVV** (%)<10 <10 <10 R E S U L T S T A R G E T T H E R A P Y 1. 2. <10 <10 <10 <10
• 43. • The LiDCO™ System provides a bolus indicator dilution method of measuring cardiac output. • A small dose of LITHIUM CHLORIDE is injected via a central or peripheral venous line ; the resulting arterial lithium concentration-time curve is recorded by withdrawing blood past a lithium sensor attached to the patient’s existing arterial line. • The dose of lithium needed (0.15 - 0.3 mmol for an average adult) is very small and has no known pharmacological effects lliiDco systemDco system
• 44. liDco™plus monitor The LiDCOplus System combines the LiDCO & PulseCO Systems software and provides a real-time and continuous assessment of a patient’s hemodynamic status. PulseCO System It’s a software (incorporated in the LiDCO™plus Monitor) that calculates continuous beat-to-beat cardiac output by analysis of the arterial blood pressure trace following calibration with an absolute LiDCO cardiac output value. This method has been shown to be accurate and reliable in various clinical settings. It has also been shown that recalibration is unnecessary for at least eight hours and more recently for 24 hours.
• 45. PULSEco system autocorrelation algorithm The analogue arterial blood pressure trace is slaved from the conventional blood pressure monitor and undergoes a three step transformation •Step 1: Arterial pressure transformation into a volume- time waveform. •Step 2: Deriving nominal stroke volume and heartbeat duration. •Step 3: Actual stroke volume via calibration with an absolute cardiac output value
• 46. liDco™plus Parameters •Body Surface Area •Systolic Pressure Variation & Pulse Pressure Variation •Cardiac Index •Oxygen Delivery & Oxygen Delivery Index •Heart Rate & Heart Rate Variation •Stroke Volume & Stroke Volume Index •Stroke Volume Variation •Intra Thoracic Blood Volume •Systemic Vascular Resistance •Systemic Vascular Resistance Index
• 47. aDvantages of liDco plus system •Provides an absolute cardiac output value via a novel and proven indicator dilution technique •Provides ITBV •Requires no additional invasive catheters •Safe – using non-toxic bolus dosages •Simple and quick to set up and can be used by nursing staff •Accurate •Temperature non-dependent •Less invasive monitoring •Utilises existing peripheral or central venous and arterial lines
• 48. Picco anD liDco plus system
• 49. electrical bioimPeDance • Make use of constant electrical current stimulation for identification of thoracic or body impedance variations induced by vascular blood flow. • Electrodes are placed in specific areas on the neck and thorax. • A low-grade electrical current, from 2 - 4 mA is emitted, and received by the adjacent electrodes. • Impedance to the current flow produces a waveform. • Through electronic evaluation of these waveforms, the timing of aortic opening and closing can be used to calculate the left ventricular ejection time and stroke volume.
• 50. electrical bioimPeDance aDvantage: •Non invasive •Some report same clinical accuracy as thermodilution technique. •New generation of EB device using upgraded computer technology and refined algorithms to calculate CO and get better results. DisaDvantage: •Reliability in critically ill patients still not very clear. •Other report poor agreement in those haemodynamically unstable and post cardiac surgery.
• 51. conclusionconclusion • Haemodynamic monitoring enable early detection of change in patient’s conditions. • New techniques provide reasonably good results and less invasive • Always correlate the readings and findings with clinical pictures in order to provide the best treatment options