This metric represents the amount of blood pumped out of the left ventricle of the heart with each contraction, adjusted for body size. It is derived by dividing the stroke volume (the volume of blood pumped per beat) by the body surface area. For example, a patient with a stroke volume of 70 mL and a body surface area of 1.7 m would have an index of approximately 41 mL/m.
Evaluating this adjusted measure provides a more accurate assessment of cardiac function than stroke volume alone, as it accounts for variations in body size. This is particularly crucial in critical care settings, where patients may have significant fluid shifts or variations in body composition. Historically, using body surface area to normalize physiological measurements has been a standard practice, allowing for more meaningful comparisons between individuals and facilitating more accurate diagnosis and treatment decisions.
