A patient's oxygen consumption is 250 mL/min. Arterial oxygen content is 200 mL/L and mixed venous oxygen content is 150 mL/L. What is the cardiac output by the Fick principle?
Answer and explanation
Correct answer: B. 5 L/min
- Step 1: Cardiac output = oxygen consumption / (arterial - venous oxygen content). Step 2. 250 / (200 - 150) = 250 / 50 = 5 L/min. Answer: 5 L/min. Why not the others: the other values come from dividing by the wrong terms.
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