What is the cardiac index for a 13-year-old patient with a cardiac output of 6.0 L/min and a body surface area of 1.5 m2?

The cardiac index is a measure of the cardiac output relative to body surface area and is calculated using the formula:

Cardiac Index (CI) = Cardiac Output (CO) / Body Surface Area (BSA).

In this scenario, the cardiac output is given as 6.0 L/min, and the body surface area is 1.5 m².

By applying the formula:

CI = 6.0 L/min / 1.5 m² = 4.0 L/min/m².

This calculation shows that for the 13-year-old patient, the cardiac index is indeed 4 L/min/m².

The significance of the cardiac index lies in its ability to provide a more accurate assessment of the heart’s performance relative to the size of the individual, making it particularly useful in pediatric and neonatal care where body sizes vary significantly. A cardiac index of 4 L/min/m² is generally within the normal range for healthy adolescents, indicating adequate cardiac function.

Thus, the option indicating a cardiac index of 4 L/min/m² is correct.