**Question:** Pulmonary function changes in acute bronchial asthma in untreated patient - a) ↑ed peak expiratory flow, b) ↓ed TLC, c) ↓ed FVC, d) ↑ed RV, e) ↑ed FEV

**Core Concept:** Bronchial asthma is a chronic inflammatory disorder of the airways characterized by airway hyper-responsiveness, bronchoconstriction, and airway inflammation. The disease leads to obstructive lung function abnormalities.

**Why the Correct Answer is Right:** In acute bronchial asthma, the airways become narrowed and inflamed, leading to a reduction in lung volumes and airflow. The correct answer highlights the following changes:

1. **a) ↑ed peak expiratory flow:** This indicates a reduction in the ability of the airways to expel air quickly, which is a result of bronchoconstriction and airway narrowing.
2. **b) ↓ed TLC (Total Lung Capacity):** TLC is the total amount of air that can be forcibly expelled from the lungs after maximal inspiration. In asthma, TLC is decreased due to bronchoconstriction and airway narrowing, leading to reduced lung compliance and decreased lung capacity.
3. **c) ↓ed FVC (Forced Vital Capacity):** FVC is the amount of air that can be forcibly exhaled from a fully inflated lung, and it is also reduced in acute asthma due to bronchoconstriction and airway narrowing, leading to impaired expiratory flow.
4. **d) ↑ed RV (Residual Volume):** RV is the volume of air remaining in the lungs at the end of a prolonged expiration. In asthma, RV increases due to bronchoconstriction and airway narrowing, leading to reduced expiratory flow rates and increased RV.
5. **e) ↑ed FEV1 (Forced Expiratory Volume in the first second):** FEV1 represents the volume of air exhaled in the first second of forced expiration. In asthma, FEV1 is reduced due to bronchoconstriction and airway narrowing, leading to impaired expiratory flow.

**Why Each Wrong Answer is Incorrect:**

1. **a) ↑ed FEV1:** This is incorrect because FEV1 is reduced in asthma due to bronchoconstriction and airway narrowing, not increased.
2. **b) ↑ed FEV2:** This is incorrect as FEV2 is not a recognized pulmonary function test measurement. FEV1 and FEV2 differ, with FEV1 being the volume of air exhaled in the first second of forced expiration and FEV2 being the volume of air exhaled in the second second of forced expiration.
3. **c) ↓ed FEV3:** FEV3 is not a recognized pulmonary function test measurement. FEV1 and FEV2 differ, with FEV1 being the volume of air exhaled in the first second of forced expiration and FEV3 being the volume of air exhaled in the