Why is Cardiac Index considered a more accurate measure than Cardiac Output alone?

Cardiac Index is considered a more accurate measure than Cardiac Output alone primarily because it accounts for body size variations. While Cardiac Output provides a measure of the total volume of blood the heart pumps per minute, it does not take into consideration the patient's body surface area. This can be a significant limitation, especially when comparing individuals of different sizes.

Cardiac Index, on the other hand, is calculated by dividing Cardiac Output by the patient's body surface area (BSA), resulting in a value that reflects the adequacy of blood flow in relation to the size of the person. This normalization allows for a more accurate assessment of cardiac function across various patients, providing clinicians with valuable information regarding how well the heart is meeting the metabolic demands of the body.

By using Cardiac Index, healthcare providers can make better decisions about treatment and management, particularly in diverse populations with varying sizes and weights.