Respiratory system-2.pdf

THE RESPIRATOTRY SYSTEM Part II  Pulmonary Congestion  Passive accumulation of blood in pulmonary vessels and capillaries  It is often the result of heart failure (Left Side) Grossly  Diffuse red discoloration of all pulmonary lobes.  Except crani...

THE RESPIRATOTRY SYSTEM Part II  Pulmonary Congestion  Passive accumulation of blood in pulmonary vessels and capillaries  It is often the result of heart failure (Left Side) Grossly  Diffuse red discoloration of all pulmonary lobes.  Except cranial margins (thin white arrows)  Lung edema Histology:  HEART FAILURE CELLS within the alveoli (alveolar macrophages filled with hemosiderin) Prussian-blue stain Congested capillaries escape Fluid and erythrocytes into the alveolar space edema and intra-alveolar hemorrhages RBCs lysis and releases hemosiderin phagocytized by alveolar macrophages “Heart failure cells"  RUPTURED PULMONARY ANEURISM  Large abscess erodes major pulmonary vessel  ABNORMALITIES OF INFLATION 1- Collapsed (Atelectasis) 2- Overinflated (Emphysema).  Pulmonary Atelectasis B- Acquired atelectasis: The previously inflated alveoli loss their air content: Causes: 1- Complete airway obstruction (b) 2- Pulmonary compression (c): Tympany, Hydrothorax Traumatic pericarditis. Grossly: 1- lung show a meaty appearance (red and firm) (white arrow) 2- Depressed in relation to the adjacent normal  Pulmonary Emphysema Over inflation of alveoli by air with destruction of walls. Causes: 1- Incomplete obstruction of bronchi or bronchiole ( foreign body or exudate) interfere with the expiration. Alveolar emphysema characterized by enlargement and rupture of the alveolar walls. Interstitial emphysema note the presence of air bubbles in the interlobular septa  Pulmonary Edema Grossly: 1- Foam comes out from the nostrils 2- The interstitial septa are distended and thickened with fluid ( marbling appearance) 3- the lung is wet  Pneumonia Definition: Acute inflammation of lung parenchyma Pneumonitis refers to chronic inflammation Route of infection of the lung: 1- Aerogenous 2- Hematogenous  CLASSIFICATION OF PNEUMONIAS According to etiology According to anatomic distribution Viral Bacterial 1- Lobular (bronchopneumonia) Parasitic Chemical 2- Lobar Immunological 3- interstitial Aspiration DURATION Microscopically: Bronchiole + alveoli filled with neutrophils mixed other inflammatory cells. (hence the name bronchopneumonia.) Microscopically: predominantly to exudation of fibrin threads (asterisks) + leukocytes.