Fick's Principle

Fick's Principle states that the amount of a substance taken up or released by an organ, like the lungs or muscles, can be determined by measuring how much of that substance is present in the blood entering and leaving the organ, along with the blood flow. Essentially, it links the difference in substance concentration across the organ to the rate of blood flow, allowing us to calculate how much of the substance is being utilized or exchanged. This principle is fundamental for assessing organ function, such as measuring how efficiently the lungs exchange oxygen or carbon dioxide.