How much air can be forcefully inhaled after normal inhalation (inspiratory reserve volume)?

The volume of air that can be forcefully inhaled after a normal inhalation is known as the inspiratory reserve volume (IRV). This volume represents the additional air that can be drawn into the lungs beyond the tidal volume, which is the amount of air inhaled during normal breathing.

In healthy adults, the inspiratory reserve volume typically ranges between 2500 mL to 3500 mL. The value often cited in textbooks and guidelines for average adults is around 3100 mL. This measurement can vary based on individual physiology, size, age, and sex.

Choosing 3100 mL accurately reflects a standard average for the IRV and aligns with commonly accepted physiological data. Higher or lower values could indicate deviations either in lung capacity or in the typical physiological ranges seen in population studies. This knowledge is essential for perfusionists, who must understand lung capacities when managing ventilation and oxygenation during surgeries or other medical procedures.