Hemodynamics

Cardiac Output (HR × SV) Calculator

Cardiac output as heart rate times stroke volume, showing which of the two is driving a change in output.

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

(HR * SV) / 1000

Reference: Normal 4–8

How it is used

• Normal resting cardiac output is 4–8 L/min.
• Output falls when either factor falls: a low stroke volume (poor filling, weak contraction or high afterload) or a rate too slow, or too fast for the ventricle to fill.
• A fast rate can hold output up while stroke volume falls, so trend stroke volume as well as output.

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

Related one-pagers

• Hemodynamic NormalsCO = HR × SV ÷ 1000 (L/min); CI = CO ÷ BSA
• Shock Types at a GlanceCardiac power output, CPO = MAP × CO ÷ 451, is normally about 1 W; below about 0.6 W predicts death (Fincke 2004). PAPi = (PA systolic − PA diastolic) ÷ RAP flags RV failure below 0.9 in inferior MI (Korabathina 2012). SCAI stages are re-scored as the patient changes; in-hospital mortality rose from about 3% at stage A to about 67% at E in a cardiac ICU cohort (Jentzer 2019). Moving from C to D is the usual shock-team trigger for mechanical support.
• Sepsis and Septic Shock BundleCardiac dysfunction · Add dobutamine, or epi alone · Low output despite fluids and pressors
• Swan-Ganz (PA Catheter): Waveforms, Wedge and Normal ValuesCardiac output · 4–8 L/min · Thermodilution or continuous

Related calculators

• Cardiac Index (CI)
• Cardiac Output (Fick Principle)
• 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.