Hemodynamics

Cardiac Index (CI) Calculator

Cardiac output scaled to body size, so flow can be compared between a small and a large patient.

Reviewed by Alex G, BSN, RN, CEN, CCRN, CMC, NREMT-P · From the Reference tab of the app

Turn on JavaScript to use this calculator, or open it in the web app.

Formula

CO / BSA

Reference: Normal 2.5–4.0

How it is used

• Normal Cardiac Index is 2.5–4.0 L/min/m².

Decreased CI (< 2.2 L/min/m²)

• Indicates hypoperfusion (cardiogenic shock, hypovolemic shock, or late distributive shock). Consider inotropes (dobutamine, milrinone) or mechanical circulatory support if filling pressures are adequate.

Elevated CI (> 4.0 L/min/m²)

• Indicates a hyperdynamic state (sepsis, liver failure, severe anemia, thyrotoxicosis).

Same formula as the app. Open it in the web app.

Related one-pagers

• Hemodynamic NormalsCI · 2.5–4.0 · L/min/m²
• Shock Types at a GlanceC: Classic · Hypoperfused; needs a drug or device · Lactate ≥2, cold, urine <30 mL/h; CI <2.2, PCWP >15
• ECMO EssentialsCircuit vs heart · In series; native heart must pump · In parallel; bypasses heart and lungs
• CEN Adult Medical Pearls: Neuro, GI and Respiratory Look-alikesCiprofloxacin 500 mg orally once · Not recommended

Related calculators

• Cardiac Output (Fick Principle)
• Cardiac Output (HR × SV)
• Cerebral Perfusion Pressure (CPP)
• Coronary Perfusion Pressure
• Ejection Fraction (EF)
• Mean Arterial Pressure (MAP)
• Oxygen Delivery (DO₂)
• Pulmonary Vascular Resistance (PVR)

For education and exam preparation only. Follow your institution’s protocols. For education and exam preparation only. Verify results independently and follow your institution’s protocols. Not a substitute for clinical judgment.