haemodynamic monitoring
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Haemodynamic Monitoring. Theory and Practice. Haemodynamic Monitoring. Physiological Background Monitoring Optimising the Cardiac Output Measuring Preload Introduction to PiCCO Technology Practical Approach Fields of Application Limitations. Physiological Background. - PowerPoint PPT PresentationTRANSCRIPT
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
3
Task of the circulatory system
Pflüger 1872: ”The cardio-respiratory system fulfils the physiological task of ensuring cellular oxygen supply”
Physiological Background
Uni Bonn
Goal Reached?
Assessment of oxygen supply and demand
OK
No
Yes
What is the problem?
DiagnosisTherapy
4
Physiological Background
Processes contributing to cellular oxygen supply
Aim: Optimal Tissue Oxygenation
Pulmonary gas exchange Macrocirculation Microcirculation Cell function
Direct Control Indirect
Oxygen AbsorptionLungs
Oxygen TransportationBlood
Oxygen DeliveryTissues
Oxygen Utilisation Cells / Mitochondria
Volume Catecholamines
Oxygen carriers Ventilation
5
Organ specific differences in oxygen extraction
Physiological Backgound
Oxygen delivery must always be greater than consumption!
SxO2 in %
modified from:Reinhart K in: Lewis, Pfeiffer (eds): Practical Applications of Fiberoptics in Critical Care Monitoring, Springer Verlag Berlin - Heidelberg - NewYork 1990, pp 11-23
6
Physiological Background
Dependency of Oxygen Demand on delivery
Behaviour of oxygen consumption and the oxygen extraction rate with decreasing oxygen supply
Oxygen consumption
DO2-independent area DO2- dependent area
Oxygen extraction rate
Decreasing Oxygen SupplyDO2: Oxygen Delivery
7
Central role of the mixed venous oxygen saturation
Physiological Background
Determinants of Oxygen Delivery and Consumption
Delivery DO2: DO2 = CO x Hb x 1.34 x SaO2
CO: Cardiac OutputHb: HaemoglobinSaO2: Arterial Oxygen SaturationSvO2: Mixed Venous Oxygen SaturationDO2: Oxygen DeliveryVO2: Oxygen Consumption
SaO2CO
Hb
8
Central role of mixed central venous oxygen saturation
Physiological Background
Determinants of Oxygen Delivery and Consumption
SaO2
S(c)vO2
Consumption VO2: VO2 = CO x Hb x 1.34 x (SaO2 - SvO2)
Delivery DO2: DO2 = CO x Hb x 1.34 x SaO2
CO
Hb
Mixed Venous Saturation SvO2
SvO2
CO: Cardiac OutputHb: HaemoglobinSaO2: Arterial Oxygen SaturationSvO2: Mixed Venous Oxygen SaturationDO2: Oxygen DeliveryVO2: Oxygen Consumption
9
Oxygen delivery and its influencing factors
Physiological Background
DO2 = CaO2 x CO = Hb x 1.34 x SaO2 x CO
Transfusion
• Transfusion CO: Cardiac Output
Hb: Haemoglobin
SaO2: Arterial Oxygen Saturation
CaO2: Arterial Oxygen Content
10
Oxygen delivery and its influencing factors
Physiological Background
DO2 = CaO2 x CO = Hb x 1.34 x SaO2 x CO
Ventilation
• Transfusion• Ventilation
CO: Cardiac Output
Hb: Haemoglobin
SaO2: Arterial Oxygen Saturation
CaO2: Arterial Oxygen Content
11
Oxygen delivery and its influencing factors
Physiological Background
DO2 = CaO2 x CO = Hb x 1.34 x SaO2 x CO
VolumeCatecholamines
• Transfusion• Ventilation• Volume• Catecholamines
CO: Cardiac Output
Hb: Haemoglobin
SaO2: Arterial Oxygen Saturation
CaO2: Arterial Oxygen Content
12
Assessment of Oxygen Delivery
Physiological Background
CO: Cardiac Output; Hb: Hemoglobin; SaO2: Arterial Oxygen Saturation
CO, HbSaO2
DO2 = CO x Hb x 1.34 x SaO2
Oxygen AbsorptionLungs
Oxygen TransportBlood
Oxygen DeliveryTissues
Oxygen UtilizationCells / Mitochondria
Supply
13
Assessment of Oxygen Delivery
Physiological Background
CO, HbSaO2
Monitoring the CO, SaO2 and Hb is essential!
Oxygen AbsorptionLungs
Oxygen DeliveryTissues
Oxygen UtilizationCells / Mitochondria
Oxygen TransportBlood
CO: Cardiac Output; Hb: Haemoglobin; SaO2: Arterial Oxygen Saturation
Supply
14
Assessment of Oxygen Delivery
Physiological Background
SvO2
SaO2 CO, Hb
Monitoring the CO, SaO2 and Hb is essential!
VO2 = CO x Hb x 1.34 x (SaO2 – SvO2)
Oxygen UtilizationCells / Mitochondria
Oxygen AbsorptionLungs
Oxygen TransportBlood
Oxygen DeliveryTissues
CO: Cardiac Output; Hb: Haemoglobin; SaO2: Arterial Oxygen Saturation
Supply
Consumption
15
Assessment of Oxygen Delivery
Physiological Background
SvO2
SaO2 CO, Hb
Monitoring CO, SaO2 and Hb is essential
Monitoring the CO, SaO2 and Hb does not give information re O2-consumption!
Oxygen UtilizationCells / Mitochondria
Oxygen AbsorptionLungs
Oxygen TransportBlood
Oxygen DeliveryTissues
CO: Cardiac Output; Hb: Haemoglobin; SaO2: Arterial Oxygen Saturation
Supply
Consumption
16
Situational Factors
Balance of Oxygen Delivery and Consumption
The adequacy of CO and SvO2 is affected by many factors
Microcirculation Disturbances
Volume status Tissue Oxygen Supply
Oxygenation / Hb level
Older Age
Body weight /heightCurrent Medical HistoryPrevious Medical History
Physiological Background
General Factors
17
Physiological Background
Extended Haemodynamic Monitoring
TherapyOptimisationO2 supplyO2 consumption
Monitoring
18
Summary and Key Points
Physiological Background
• The purpose of the circulation is cellular oxygenation
• For an optimal oxygen supply at the cellular level the macro and micro-circulation as well as the pulmonary gas exchange have to be in optimal balance
• Next to CO, Hb and SaO2 is SvO2 which plays a central role in the assessment of
oxygen supply and consumption
• No single parameter provides enough information for a full assessment of oxygen supply to the tissues.