Most common type of emphysema

Ans. (c) Centriacinar emphysemaRef: Harrison 19th ed. /1701Emphysema: The abnormal permanent enlargement of air spaces distal to the terminal bronchioles, accompanied by the destruction of the walls and without obvious fibrosis. It begins in the respiratory bronchioles and spreads peripherally.SMOKING CAUSES intake of TAR which causes | marcrophages in alveolar region. These macrophages secrete enzyme Elastase which causes autodigestion of elastin a leading to | elasticity a EmphysemaCentriacinar emphysema is MOST COMMON FORM.* Associated with smoking* Usually seen in apices* Causes type-I respiratoryfailure: |pO2 |pCO2* MOST RELIABLE radiographic sign: Flattening of the diaphragm* Symptoms:Persistent cough, Dyspnea, Wheezing, Chest pain, Fever.* Upon examination:# Increased RR# BARREL SHAPED CHEST (AP diameter > transverse)# No cyanosis# Pink puffersAlso Know*Panlobular emphysema: involves entire ecinus UNIFORMLY.* Paraseptal emphysema: involves only distal acinus (alveolar ducts and sac). Found near pleura and can result in pneumothorax.* Irregular or cicatricial: can be either of them.