Enter the pulmonary physiologic shunt (mL/min) and the cardiac output (mL/min) into the Shunt Equation Ratio Calculator. The calculator will evaluate the Shunt Equation Ratio. 

Shunt Equation Ratio Formula

The following two example problems outline the steps and information needed to calculate the Shunt Equation Ratio.

SE = Qs / Qt


  • SE is the Shunt Equation Ratio ( )
  • Qs is the pulmonary physiologic shunt (mL/min) 
  • Qt is the cardiac output (mL/min) 

How to Calculate Shunt Equation Ratio?

The following steps outline how to calculate the Shunt Equation Ratio.

  1. First, determine the pulmonary physiologic shunt (mL/min). 
  2. Next, determine the cardiac output (mL/min). 
  3. Next, gather the formula from above = SE = Qs / Qt.
  4. Finally, calculate the Shunt Equation Ratio.
  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.

pulmonary physiologic shunt (mL/min) = 14.75

cardiac output (mL/min) = 16..00

SE = Qs / Qt = ?