Enter the oxygen consumption and the difference between arterial and venous oxygen content into the calculator to determine the Fick Cardiac Output.

Fick Cardiac Output Formula

The following formula is used to calculate the Fick Cardiac Output:

 CO ={VO_2}/{(CaO_2 - CvO_2)}


  • CO is the Fick Cardiac Output
  • VO_2 is the oxygen consumption
  • CaO_2 is the arterial oxygen content
  • CvO_2 is the venous oxygen content

To calculate the Fick Cardiac Output, divide the oxygen consumption by the difference between arterial and venous oxygen content.

What is a Fick Cardiac Output?

Fick Cardiac Output is a method used to determine the cardiac output of a person’s heart. Cardiac output refers to the amount of blood the heart pumps through the circulatory system in a minute. The Fick principle, named after Adolf Fick, states that the blood flow to an organ can be calculated using a marker substance if the following information is known: the amount of the substance taken up by the organ per unit time, the concentration of the substance in the arterial blood supplying the organ, and the concentration of the substance in the venous blood leaving the organ. In the case of Fick Cardiac Output, oxygen is typically used as the marker substance. The method involves measuring the oxygen consumption in the lungs, the oxygen concentration in arterial blood, and the oxygen concentration in venous blood. The difference in oxygen concentration in the arterial and venous blood gives the amount of oxygen consumed by the body tissues, which is then used to calculate the cardiac output.

How to Calculate Fick Cardiac Output?

The following steps outline how to calculate the Fick Cardiac Output:

  1. First, determine the oxygen consumption (VO2) in ml/min.
  2. Next, determine the arterial oxygen content (CaO2) in ml/dL.
  3. Next, determine the venous oxygen content (CvO2) in ml/dL.
  4. Finally, calculate the Fick Cardiac Output using the formula: CO = VO2 / (CaO2 – CvO2).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Oxygen consumption (VO2) = 250 ml/min

Arterial oxygen content (CaO2) = 20 ml/dL

Venous oxygen content (CvO2) = 15 ml/dL