How is Cardiac Index (C.I.) defined?

Cardiac Index (C.I.) is defined as the Cardiac Output (CO) divided by Body Surface Area (BSA). This measurement is important because it provides a more accurate assessment of cardiac function relative to an individual's size. By normalizing Cardiac Output to Body Surface Area, Cardiac Index allows for comparisons across patients of different body sizes, making it a valuable tool in clinical practice.

Understanding the significance of Cardiac Index helps healthcare providers evaluate cardiac performance more effectively. A normal range for Cardiac Index is typically between 2.5 to 4.0 L/min/m². If Cardiac Index is low, it may indicate inadequate cardiac output for the body’s metabolic needs, leading to potential clinical interventions. On the other hand, a high Cardiac Index may suggest hyperdynamic circulation often seen in conditions like sepsis.

The other choices do not accurately represent the definition of Cardiac Index, as they either misplace the division, combine the variables incorrectly, or situate them in a way that does not yield a meaningful clinical measure. Thus, understanding that Cardiac Index is derived from the relationship of Cardiac Output to Body Surface Area is essential for interpreting cardiovascular function properly.