1. HEMODYNAMIC PRESSURE MONITORING Dr. Mueen Ullah Khan Assitant professor Department of Anaesthesia KKUH December 2 2009 Lecture series resident 1 and 2 Anaesthesia
14. COMPONENTS 1. Transducer Change mechanical energy to electronic signal. 2. Continuos washing system Saline solution in a pressure bag (300mmHg) or infusion pump ( less fluid volume!!! ) 3. Proximal stopcock Useful to set “Zero”. 4. Connection to catheter Transfer pressure pulse from caterer to transducer 5. Distal stopcock Useful to take out blood sample. 2 4 5 INTRAVASCULAR PRESSURE MONITORING 1 3
15. Transducer system CONNECTION LINE: SHORTER , LONG and STIFFER! INTRAVASCULAR PRESSURE MONITORING Resonance Damping
16. Calibration - “ZERO” WHY R emove atmospheric pressure interference (~760mmHg) WHEN connection from transducer to monitor Not when you change transducer position!!! TEST Open Proximal Stopcock to connect transducer to air , monitor must show a Straight line and measure “zero”. SET: RANGE Measured pressure is always relative to a reference point. It’s a difference! INTRAVASCULAR PRESSURE MONITORING
17. Level: Reference point RIGHT ATRIUM = “ Mean Axillary Line” Supine position WHEN: SET LEVEL Every time patient moves (Otherwise measurement is not right!!!) INTRAVASCULAR PRESSURE MONITORING
18. RAPID FLUSH TEST To determinate the dynamic response of catheter and transducer system Overdamped INTRAVASCULAR PRESSURE MONITORING
22. Invasive arterial pressure - 4 INTRAVASCULAR PRESSURE MONITORING NORMAL RANGE SYSTOLIC BLOOD PRESSURE Age Wt mmHg Term 3.4kg 40-60 3 mo 6kg 45-75 6 mo 7.5kg 50-90 1 yr 10kg 50-100 3yr 14kg 50-100 7yr 22kg 60-90 10yr 30kg 60-90 12yr 38kg 65-95 14yr 50kg 65-95
23. Invasive arterial pressure INTRAVASCULAR PRESSURE MONITORING RESPIRATORY CHANGES IN ARTERIAL WAVE FORM IN MECHANICALLY VENTILATED PATIENTS SYSTOLIC PRESSURE VARIATION - SPV PULSE PRESSURE VARIATION - PPV
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25. Invasive arterial pressure INTRAVASCULAR PRESSURE MONITORING SYSTOLIC PRESSURE VARIATION - SPV The difference between the maximal and minimal value of systolic blood pressure during one mechanical breath. SPV can be divided into two components by interposing a brief (5sec) apnea, and using the systolic blood pressure during apnea as a reference value: down up The difference between the maximal systolic value and the systolic blood pressure during apnea. The difference between the apneic systolic blood pressure and the minimal systolic value.
27. Invasive arterial pressure INTRAVASCULAR PRESSURE MONITORING SYSTOLIC PRESSURE VARIATION - SPV Down reflects the expiratory decrease in LV preload and SV related to the inspiration decrease in RVSV
39. CVP – Central Venous Pressure / Right Atrium waveform • TRICUSPID REGURGITATION: Elevated CVP Evident positive V wave • CARDIAC TAMPONADE: Elevated CVP Damping or absence of Y wave Equalization of CVP, diastolic PAP and PAWP INTRAVASCULAR PRESSURE MONITORING
48. MEASUREMENTS: Cardiac Output Thermodilution (Fegler G., 1954/Ganz W, 1971) Cold solution in injected into right atrium. The thermistor records blood temperature change on the top of pulmonary artery catheter. Stewart-Hamilton formula CO = Vol injected x (TB-TF)1.08K/ ? ? TB(t)dt • TB, TF = Blood and cold fliud temperature • ?? TB(t)dt = under-curve area • K = computational constants INTRAVASCULAR PRESSURE MONITORING Pulmunary Artery Catheter - 6
50. MEASUREMENTS: Pulmonary Artery Occlusion Pressure (PAOP) INTRAVASCULAR PRESSURE MONITORING Pulmunary Artery Catheter - 7 In Pediatric Cardiac Surgery you can put a catheter direct In Left Atrium LVEDP LAP