Review
Minimally invasive CO monitors
Esophageal Doppler
Echocardiography
Pulse contour analysis
PiCCO system
Flo-Trac
Lithium dilution CO
Bioimpedance
Bioreactance
Fick's principle
Conclusions
Advantages | Disadvantages | |
---|---|---|
PAC | Pulmonary infarction | |
Measure CVP | Rupture of pulmonary artery | |
Intermittent and continuous | Arrhythmias | |
SVR can be obtained | Need right heart catheterization | |
Pulse wave
Analysis
| ||
A. PICCO
| ||
Intermittent and continuous | Need a central venous access | |
Measures GEDV/EVLW | ||
Estimate preload | ||
B. LIDCO
| ||
Intermittent and continuous | Cannot be used if patient on lithium or NDM | |
SVR can be obtained | Need frequent blood drawing | |
Does not estimate preload | ||
C. Flo-trac
| SVR can be obtained | Not reliable in very high CO state |
Measure PPV/SVV | Perform poorly with tachyarrhythmia | |
Many validation studies | Valvular pathology prevents accurate reading of CO | |
Esophageal Doppler
| Less invasive | Needs intubated patient |
Simple to use | Only measure descending aortic flow | |
Not good in AR | ||
Echocardiography
| Provides detailed cardiac information | Needs additional training |
Estimate preload | Inability to image patient | |
Bioreactance
| Non-invasive | Numerous mathematical assumptions |
Continuous | Signal stability fails after 24 h | |
Sensors can be placed anywhere in thorax and back | ||
Bioimpedence
| Continuous | Numerous mathematical assumptions |
Difficult to set up | Signal stability fails after 24 h | |
Flick's Principle
| Easy set up | Not suitable for unstable patient |
Provides additional ventilatory parameters | Shunt can affect CO estimation |