Static Lung Compliance on ventilation is typically within which range?

Static Lung Compliance on ventilation is typically within which range?

• A. 10-20 mL/cm H2O
• B. 200-300 mL/cm H2O
• C. 60-100 mL/cm H2O
• D. 5-15 cm H2O

Answer: (C)

Static lung compliance describes how much air volume you get for a given distending pressure when there is no airflow. It’s measured during an inspiratory hold as Crs = Vt / (Pplat − PEEP). In healthy adults, the total respiratory system is typically about 60–100 mL per cm H2O, meaning a 1 cm H2O increase in transpulmonary pressure yields roughly 60–100 mL of tidal volume. That range best reflects normal distensibility of the lungs and chest wall during ventilation. Choices that yield much lower values would indicate stiffer lungs, while unrealistically high values exceed physiologic limits. A pressure-only figure (5–15 cm H2O) isn’t a compliance measure and doesn’t convey how much volume responds per unit pressure.

Static lung compliance describes how much air volume you get for a given distending pressure when there is no airflow. It’s measured during an inspiratory hold as Crs = Vt / (Pplat − PEEP). In healthy adults, the total respiratory system is typically about 60–100 mL per cm H2O, meaning a 1 cm H2O increase in transpulmonary pressure yields roughly 60–100 mL of tidal volume. That range best reflects normal distensibility of the lungs and chest wall during ventilation.

Choices that yield much lower values would indicate stiffer lungs, while unrealistically high values exceed physiologic limits. A pressure-only figure (5–15 cm H2O) isn’t a compliance measure and doesn’t convey how much volume responds per unit pressure.