Restrictive pulmonary disorders primarily restrict which phase of breathing?

• A. Expiration
• B. Inspiration
• C. Forced breathing
• D. Controlled breathing

Answer: (B)

Restrictive pulmonary disorders primarily affect the inspiration phase of breathing. This type of disorder is characterized by a reduction in lung volume, leading to difficulty in fully expanding the lungs. Conditions such as pulmonary fibrosis, pneumothorax, or neuromuscular diseases that impede the thoracic wall's movement can restrict the airflow into the lungs during inhalation.

The pathophysiology behind this restriction often involves increased stiffness of the lung tissue or chest wall, making it challenging for the respiratory muscles to achieve an adequate expansion of the thoracic cavity. As a result, patients with restrictive disorders may experience shortness of breath, particularly during physical activities requiring increased airflow, due to their inability to take in sufficient air.

While expiration is also a crucial phase of breathing, the primary impact of restrictive disorders is seen during inhalation. In contrast, forced breathing and controlled breathing refer more to the manner in which air is inhaled and exhaled under certain conditions, rather than being directly linked to the limitations imposed by restrictive lung pathology.