Question

Consider a healthy person with the following lung volumes: Residual volume = 900 mL Expiratory reserve volume = 800 mL Tidal volume = 200 mL If the Total lung capacity is 5500 mL, then the Inspiratory reserve volume of the person is ____ mL. (Answer in integer)

Hint:

Understanding lung volumes and capacities is crucial in pulmonary function testing and assessing respiratory health.

Answer 1

Step 1: Understanding the Components of Total Lung Capacity

Total lung capacity (TLC) is the sum of all the volumes:

\[ \text{TLC} = \text{RV} + \text{ERV} + \text{TV} + \text{IRV} \]

Where:

• \(\text{RV}\) = Residual Volume
• \(\text{ERV}\) = Expiratory Reserve Volume
• \(\text{TV}\) = Tidal Volume
• \(\text{IRV}\) = Inspiratory Reserve Volume

Step 2: Inserting the Given Values

Given that:

\[ \text{RV} = 900 \text{ mL} \] \[ \text{ERV} = 800 \text{ mL} \] \[ \text{TV} = 200 \text{ mL} \] \[ \text{TLC} = 5500 \text{ mL} \]

We can rearrange the formula to solve for \( \text{IRV} \):

\[ \text{IRV} = \text{TLC} - (\text{RV} + \text{ERV} + \text{TV}) \] \[ \text{IRV} = 5500 - (900 + 800 + 200) \] Step 3: Calculating the Inspiratory Reserve Volume \[ \text{IRV} = 5500 - 1900 \] \[ \text{IRV} = 3600 \text{ mL} \] Conclusion:

Explanation: The Inspiratory Reserve Volume for this person is **3600 mL**, which represents the maximum volume of air that can be inhaled after a normal inhalation.