What is the normal range of cardiac output?

What is the normal range of cardiac output?

• A. 2-4 L/min
• B. 4-8 L/min
• C. 8-12 L/min
• D. 1-2 L/min

Answer: (B)

Cardiac output is the amount of blood the heart pumps each minute, and it depends on heart rate and stroke volume (CO = HR × SV). In a healthy adult at rest, heart rate is usually about 60–100 bpm and stroke volume around 70 mL, which yields roughly 4–5 L/min. Across individuals, the resting range is typically 4–8 L/min, which is why this option fits best as the normal resting value. Values much lower (around 2 L/min) would indicate poor perfusion or shock, while resting values approaching 8–12 L/min would be unusually high for a non-exercising person. During exercise, cardiac output can rise substantially, often well above 8 L/min, up to 12–20 L/min in trained individuals.

Cardiac output is the amount of blood the heart pumps each minute, and it depends on heart rate and stroke volume (CO = HR × SV). In a healthy adult at rest, heart rate is usually about 60–100 bpm and stroke volume around 70 mL, which yields roughly 4–5 L/min. Across individuals, the resting range is typically 4–8 L/min, which is why this option fits best as the normal resting value. Values much lower (around 2 L/min) would indicate poor perfusion or shock, while resting values approaching 8–12 L/min would be unusually high for a non-exercising person. During exercise, cardiac output can rise substantially, often well above 8 L/min, up to 12–20 L/min in trained individuals.