• Cardiac output monitoring
• PAFC is still considered by some to be the gold standard
• Clinical assessment
• Agitation, confusion
• High RR due to acidaemia
• Reduced u.o.
• CRT
• May have warm peripheries and bounding pulse in sepsis
• PAFC
• Uses the Fick principle and spirometer to calculate oxygen consumption
• Dye (indocyanine green) and thermodilution used more now
• May be affected by cardiac shunt, TR, PR, positive pressure ventilation cycling
• Lithium dilution
• 0.15mmol injected
• Plasma concentrations measured from arterial line
• Cardiac output is calculated by AUC of conc vs time.
• Fick partial recirculating method
• Q = VCO₂/(CaCO₂ - C⊽CO₂)
• Parameters measure from art line and expired gases
• Doppler USS techniques
• ODM
• TOE
• Also allows assessment of ventricular function, wall abnormalities, valve function and anatomy
• It measures velocity of flow across a valve eg aortic valve
• The area under this flow-velocity curve (velocity time integral -VTI) is related to the systolic function. It also determins the cross-sectional area (CSA) of the aortic valve when open.
• VTI X CSA = SV
• Thoracic electrical impedance
• Blood ejection changes electrical impedance of the thoracic cavity
• A high frequency, low voltage AC is applied to the chest and sensed by an electrode at the xiphoid and neck.
• Not very reliable and doesn't correlate brilliantly with PAFC
• Arterial waveform analysis (PiCCO)
• Via femoral, brachial or axillary line
• Uses CVP to give thermodilution to calibrate (thermistor in arterial line)
• The area under the waveform is used to derive ejection systolic area
• Can be combined with lithium dilution (LiDCO)
• CEACCP
  Link:ceaccp.oxfordjournals.org/content/3/1/15.full.pdf
  
• CEACCP
  Link:ceaccp.oxfordjournals.org/content/12/1/5.full.pdf