How is cardiac output calculated?

How is cardiac output calculated?

• A. Heart Rate (HR) plus Stroke Volume (SV).
• B. Heart Rate (HR) times Stroke Volume (SV).
• C. Blood Pressure (BP) times Heart Rate (HR).
• D. Systemic Vascular Resistance times Stroke Volume (SV).

Answer: (B)

Cardiac output is the amount of blood the heart pumps each minute. It depends on two factors: how many times the heart beats per minute (heart rate) and how much blood is ejected with each beat (stroke volume). The total volume pumped per minute is the product of these two, so CO = HR × SV. For example, if the heart beats 70 times per minute and ejects 70 mL with each beat, CO ≈ 4900 mL/min (about 4.9 L/min). This is why multiplication, not addition, gives the correct calculation. Blood pressure and systemic vascular resistance affect circulation but aren’t used to calculate cardiac output directly.

Cardiac output is the amount of blood the heart pumps each minute. It depends on two factors: how many times the heart beats per minute (heart rate) and how much blood is ejected with each beat (stroke volume). The total volume pumped per minute is the product of these two, so CO = HR × SV. For example, if the heart beats 70 times per minute and ejects 70 mL with each beat, CO ≈ 4900 mL/min (about 4.9 L/min). This is why multiplication, not addition, gives the correct calculation. Blood pressure and systemic vascular resistance affect circulation but aren’t used to calculate cardiac output directly.