Cardiac Index Calculator

Calculates cardiac index from cardiac output and BSA.

Inputs

Color mode links each input to the matching equation term and solving arithmetic.

Equation and Work

Primary equation:
BSA support equation:
Solving steps:
BSA
—
m²
Cardiac index
—
L/min/m²
Normal/reference: CI 2.5–4.0 L/min/m². Values >4 may occur with stress/sepsis/hypervolemia; values <2.5 may occur with blood loss, LV failure, or MI.

Clinical Significance

Cardiac index normalizes cardiac output to body surface area: cardiac output is divided by BSA. When this page estimates BSA from weight, the constants 4, 7, and 90 belong to the simplified weight-based BSA equation used in the reference text.

CI helps compare cardiac pump performance between patients of different body sizes.

CI depends on the accuracy of cardiac output and the BSA estimate used.

References (APA 7th Edition)

  1. Attached equations reference supplied by the user for calculator equation confirmation.