Using VO2 = QT (CaO2 - CvO2) x 10, calculate VO2 when QT = 5 L/min, CaO2 = 18, CvO2 = 12.

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Using VO2 = QT (CaO2 - CvO2) x 10, calculate VO2 when QT = 5 L/min, CaO2 = 18, CvO2 = 12.

The concept here is the Fick principle: oxygen consumption equals how much blood the heart pumps each minute (cardiac output) times how much oxygen is extracted from that blood (arterial minus venous O2 content). The difference in O2 content is CaO2 − CvO2 = 18 − 12 = 6 mL O2 per 100 mL blood. With a cardiac output of 5 L/min, convert to deciliters: 5 L/min = 50 dL/min. Multiply 50 dL/min by 6 mL/dL to get 300 mL O2 per minute. Using the given formula with the unit conversion factor, 5 × 6 × 10 also yields 300 mL/min. So the VO2 is 300 mL/min.

The concept here is the Fick principle: oxygen consumption equals how much blood the heart pumps each minute (cardiac output) times how much oxygen is extracted from that blood (arterial minus venous O2 content). The difference in O2 content is CaO2 − CvO2 = 18 − 12 = 6 mL O2 per 100 mL blood. With a cardiac output of 5 L/min, convert to deciliters: 5 L/min = 50 dL/min. Multiply 50 dL/min by 6 mL/dL to get 300 mL O2 per minute. Using the given formula with the unit conversion factor, 5 × 6 × 10 also yields 300 mL/min. So the VO2 is 300 mL/min.

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