Marino The ICU Book 4e, IE

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The Pulmonary Artery Catheter

FIGURE 8.6 Thermodilution curves for a low cardiac output (upper panel) , a high cardiac output (middle panel) , and tricuspid insufficiency (lower panel). The sharp inflection in each curve marks the end of the measurement period. CO = cardiac output.

fluid passes through the shunt, thereby creating an abbreviated thermod- ilution curve similar to the high-output curve in the middle panel of Figure 8.6. In left-to-right shunts, the thermodilution curve is abbreviat- ed be-cause the shunted blood increases the blood volume in the right heart chambers, and this dilutes the indicator solution that is injected. HEMODYNAMIC PARAMETERS The PA catheter provides a wealth of information on cardiovascular func- tion and systemic oxygen transport. This section provides a brief de- scription of the hemodynamic parameters that can be measured or de- rived with the PA catheter. These parameters are included in Table 8.1. Body Size Hemodynamic parameters are often expressed in relation to body size,