Term | Definition |
atelectasis (collapsed lung) | loss of lung volume caused by inadequate expansion of airspaces |
resorption atelectasis | an obstruction prevents air from reaching distal airways; often after anesthesia and mucous plugs |
compression atelectasis | accumulation of blood, fluid or air in pleural cavity, causing the lung to collapse; after effusions and CHF |
contraction atelectasis | fibrotic changes in the lungs or pleura; irreversible |
acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) | continuum of respiratory failure; symptoms include dyspnea, hypoxemia (decreased arterial oxygen pressure), and absence of left heart failure
-{most common cause of noncardiogenic pulmonary edema}
-caused by either {direct injury} or {indirect injury} |
ARDS pathogenesis | neutrophils thought to play an important role |
diffuse alveolar damage | histologic manifestation of ARDS |
acute phase | stage of diffuse alveolar damage; capillary congestion, necrosis and collection of neutrophils
-{hyaline membranes} form |
hyaline membranes | protein-rich edematous fluid mixed with necrotic epithelial cells |
organizing phase | phase of diffuse alveolar damage; proliferation of type II pneumocytes and phagocytosis of hyaline membranes |
diffuse interstitial fibrosis | may occur after the acute phase of diffuse alveolar damage; compromises lung function |
obstructive disease | limitation of airflow from increased resistance due to obstruction
-includes emphysema, chronic bronchitis, asthma and bronchiectasis |
restrictive disease | reduced expansion of lung parenchyma and decreased total lung capacity; both chronic and acute forms
-includes ARDS, idiopathic pulmonary fibrosis (IPF), pneumoconiosis and sarcoidosis |
chronic obstructive pulmonary disease (COPD) | usually a combination of chronic bronchitis and emphysema
{major etiologic factor is cigarette smoking} |
emphysema | anatomic entity restricted to the acini; abnormal, permanent enlargement of the airspaces |
centriacinar emphysema | central/proximal parts of the acinus is affected (aka the respiratory bronchioles) but the distal alveoli are unaffected
-more common in upper part of lungs and seen as a consequence of {cigarette smoking} |
panacinar emphysema | effects the entire acinus in the lower parts of the lungs; often due to {alpha1-antitrypsin deficiency} |
distal acinar emphysema | effects the distal acinus, adjacent to the pleura; can cause spontaneous pneumothorax |
irregular emphysema | acinus is irregularly involved; associated with scarring after inflammatory diseases |
protease-antiprotease imbalance hypothesis | theory of emphysema pathogenesis; people with alpha1-antitrypsin deficiencies develop emphysema because their elastic tissue is destroyed |
oxidant-antioxidant imbalance hypothesis | theory of emphysema pathogenesis; oxidative injury recruits neutrophils and inactivates antiproteases |
'pink puffers' | describes clinical course of emphysema; no bronchitic component, barrel chest with dyspnea and hyperventilation but normal gas levels |
'blue bloaters' | describes clinical course of emphysema; history of bronchitis, patients are hypoxic and cyanotic |
chronic bronchitis | clinical presentation of persistent cough for 3 months in 2 consecutive years; due to hyper secretion of mucous from metaplastic transformation of mucin-secreting goblet cells |
asthma | episodic, reversible bronchospasm from and exaggerated bronchconstrictor response |
atopic asthma | asthmatic episode initiated by type I IgE-mediated hypersensitivity reaction to an antigen; most common type, hereditary, and driven by TH2 subset of CD4 T cells |
non-atopic asthma | triggering mechanism of asthmatic episode is not immune; no family history and normal IgE levels |
airway remodeling | persistent inflammation that leads to structural changes in bronchial walls; hypertrophy of bronchial smooth muscle and mucous glands, increased vascularity and collagen deposition
-pathogenesis of atopic asthma |
status asthmaticus | sudden asthma attack that does not respond to therapy and persists for days to weeks |
bronchiectasis | permanent dilation of bronchi and bronchioles due to chronic necrotizing infections |
predisposing conditions to bronchiectasis: | 1. bronchial obstruction 2. congenital/hereditary conditions 3. necrotizing/suppurative pneumonia |
chronic restrictive (interstitial) lung diseases | hallmark is reduced compliance so breathing takes more effort
-includes IPF, the pneumoconiosis, and sarcoidosis |
idiopathic pulmonary fibrosis (IPF) | patchy but progressive interstitial fibrosis causes hypoxia and cyanosis; breathing sounds like velcro crackling |
pneumoconioses | group of diseases caused by inhaling irritants, allergens or toxic aerosols; particles 1-5 micrometers are most damaging
-{pulmonary alveolar macrophage is key cellular element in initiation and perpetuation of lung injury and fibrosis} |
Caplan syndrome | coexistence or rheumatoid arthritis with one of the pneumoconiosis; forms nodular lesions |
coal workers' pneumoconiosis (CWP) | spectrum of lung findings in coal workers
-{does not increase risk of lung cancer in non-smokers} |
anthracosis | pigment accumulation in CWP without cellular reaction |
simple CWP | cellular accumulation of macrophages with little dysfunction
-contains coal macule and nodules |
coal macule | dust-laden macrophage |
coal nodule | dust-laden macrophage with network of collagen fibers surrounding |
complicated CWP / progressive massive fibrosis (PMF) | extensive fibrosis and compromised lung function |
silicosis | inhalation of crystalline silica; carcinogenic and predisposes to tuberculosis |
acute silicosis | shortly after exposure to high levels of silica; develops quickly |
chronic silicosis | silica exposure over a prolonged time with formation of fibrotic nodules; latency period before onset |
complicated silicosis | progression of chronic silicosis with coalescence of nodules into hard scars; progresses to PMF |
asbestosis | marked by diffuse pulmonary interstitial fibrosis, indistinguishable from other fibrotic lung diseases
-progresses to CHF, cor pulmonale and death |
serpentine | asbestosis with curly, flexible fibers |
amphibole | asbestosis with straight, stiff fibers; more pathogenic and predisposes to {malignant mesothelioma} |
asbestos bodies | distinguishes asbestosis; asbestos fibers coated in iron-containing proteinaceous fluid left from macrophage that tried to engulf it |
pleural plaques | asymptomatic plaques of dense collagen |
sarcoidosis | multisystem, idiopathic disease with {non-caveating granulomas in tissues and organs}
-higher prevalence in non-smokers |
bilateral hilar lymphadenopathy | major manifestation of sarcoidosis |
death from sarcoidosis due to: | 1. progressive pulmonary fibrosis 2. cor pulmonale |