Using DO2 = CO × CaO2 and CaO2 ≈ 20 mL/dL with CO = 5 L/min, what is the approximate DO2?

Study for the Respiratory Therapy Test. Use flashcards and multiple choice questions, featuring hints and explanations. Prepare for your exam successfully!

Multiple Choice

Using DO2 = CO × CaO2 and CaO2 ≈ 20 mL/dL with CO = 5 L/min, what is the approximate DO2?

The main idea is to multiply how much oxygen is carried per unit of blood by how much blood the heart pumps each minute, making sure the units line up. CaO2 is given as 20 mL of O2 per deciliter of blood. Cardiac output is 5 L per minute. Convert CO to deciliters per minute (since CaO2 is per deciliter) or convert CaO2 to per liter. Using deciliters: 5 L/min equals 50 dL/min. Multiply by 20 mL/dL → 50 × 20 = 1000 mL O2 per minute. Using liters: CaO2 per liter is 20 mL/dL × 10 dL per L = 200 mL O2/L. Multiply by 5 L/min → 5 × 200 = 1000 mL O2 per minute. Therefore, approximate DO2 is 1000 mL/min.

The main idea is to multiply how much oxygen is carried per unit of blood by how much blood the heart pumps each minute, making sure the units line up. CaO2 is given as 20 mL of O2 per deciliter of blood. Cardiac output is 5 L per minute. Convert CO to deciliters per minute (since CaO2 is per deciliter) or convert CaO2 to per liter.

Using deciliters: 5 L/min equals 50 dL/min. Multiply by 20 mL/dL → 50 × 20 = 1000 mL O2 per minute.

Using liters: CaO2 per liter is 20 mL/dL × 10 dL per L = 200 mL O2/L. Multiply by 5 L/min → 5 × 200 = 1000 mL O2 per minute.

Therefore, approximate DO2 is 1000 mL/min.

More practice questions