Transcript CVS Monitoring

CVS Monitoring in Shock
CVS Monitoring
Non-invasive techniques:
• Clinical assessment of tissue perfusion
• ECG, NiBP, pulse oximetry;
• Non-invasive CO studies – Echo, NiCO method
Invasive Monitoring:
• Central venous pressure monitoring;
• Direct arterial line pressure monitoring;
• Cardiac Output studies (Pulmonary Artery Catheter)
Central Venous Catheterisation
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Internal jugular vein
Subclavian vein
Axillary vein
Femoral vein
The absolute value is often unhelpful, except in extreme cases
of severe hypovolaemia, significant fluid overload, or heart
failure.
Correct interpretation requires assessment of the change in
central venous pressure in response to a fluid challenge
in conjunction with alterations in other monitored variables.
Other Indications for CVC: Drug delivery (Adrenaline,
Noradrenaline, Potassium, other hypertonic solutions),
Total Parenteral Nutrition (TPN), etc.
Complications of central catheters
• On insertion
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Cardiac arrythmias
Pneumothorax / haemothorax
Air embolism
Surrounding tissue injuries
Cardiac tamponade
• Post insertion
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Infection (consider removal after 7 days)
Cardiac arrhythmias
Displacement of catheter
Blockage of lumen(s)
Air / material embolism
Thrombus formation
Direct arterial pressure monitoring
Invasive cannulation of an artery for continuous
monitoring of direct BP; used in:
-Haemodynamically unstable patient, patient in shock
-Patient receiving inotropic / vasoactive agents
-For blood sampling (ABG’s, U&E’S, glucose etc)
-Patient with physiological difficulties for NIBP (obesity, AF)
Stroke volume variation (SVV) :
difference between the largest and the
smallest arterial wave traces during
respiratory cycle
SPV and PVI
Techniques to assess cardiac output
(Flow-based techniques)
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Oesophageal Doppler
• based on determination of RBC velocity/flow
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Trans-oesophageal Echocardiography (TOE)
• Gold standard in USA
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Arterial pulse/pressure wave analysis (PPWA)
• eg PiCCO, Vigileo, LiDCO
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Combination of pulse/pressure wave analysis (PPAW) with
oesophageal Dopler flow measurement (for re calibration)
Bioimpedance / Bioreactance
• Change in amplitude / frequency of a transmitted electrical signal
Oesophageal Doppler
Pulse contour analysis
PPWA
If an arterial pressure waveform is calibrated to a known cardiac
output then tracking the changed in the shape and size of arterial
waveform can give information to the changes in cardiac output.
Pulmonary artery catheterisation
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Dr. Jeremy Swan and Dr. William Ganz
Developed 1971
Catheterisation of the pulmonary artery with a balloon
flotation catheter allows to measure:
• Preload - indirect assessment of the filling pressure of the left
ventricle (pulmonary artery occlusion or wedge pressure)
• Contractility – by using ‘thermodilution’ technique
• Afterload or SVR - by calculating from the formula
SVR = CO / MAP
(PAC; PAFC; PAOP; PAWP)