Respiratory tract Flashcards Preview

Pathology > Respiratory tract > Flashcards

Flashcards in Respiratory tract Deck (15)
Loading flashcards...

Upper airway

Nose, accessory air sinuses, nasopharynx, larynx
Warm, humidify & filter air carried through the respiratory tree down to the trachea, through bronchioles and into the alveoli where gas exchange takes place


Lower airway

Trachea, bronchi (have cartilage) bronchioles, terminal bronchioles (have smooth muscle), alveoli


Infections in upper airways

acute inflammatory process that affects mucous membranes
eg. rhinitis, laryngitis, tonsillitis, sinusitis
symptoms = malaise, headache, sore throat, discharge
commonly viral, can get secondary bacterial infection


Infections in lower airways - Pneumonia

inflammation of the lung parenchyma
exudate with inflammatory cells and fibrin in alveolar spaces
causes = infectious agents, inhalation of chemicals, chest wall trauma


Categories of pneumonia

Community acquired -
elderly population, strep. pneumonia most common organism, flu and staph, aureus
Hospital acquired -
usually bacterial gram negative staph aureus
severe and can be fatal, symptoms = fever, increase WBC, chest x-ray changes
Aspiration pneumonia -
develops after inhalation of foreign material
elderly, stroke, dementia, anaesthetic
usually R middle and R lower lobe
oral flora positive
Chronic pneumonia
Necrotizing pneumonia


Obstructive disorders

characterized by partial/complete obstruction at any level from trachea to respiratory bronchioles
pulmonary function test = limitation of maximal airflow rate during forced expiration


Restrictive disorders

characterized by decreased expansion with decreased total lung capacity
Forced vital capacity is reduced = amount of air that can be blown out after maximal inspiration
heterogenous group of diseases
inflammation and fibrosis of the pulmonary connective tissue


COPD - emphysema (obstructive)

irreversible enlargement of airspaces distal to terminal bronchiole
destruction of walls
types = centriacinar/panacinar /paraseptal / irregular
morphology = voluminous lungs, large alveoli, large apical bullae
symptoms = SOB, cough, wheezing, weight loss, congestive heart failure


COPD - chronic bronchitis (obstructive)

for at least 3 months in a 2 year period
long-standing irritation by inhaled substances
hypertrophy of submucosal glands in trachea & bronchi = increased goblet cells
mucus hypersecretion and alteration in small airways = chronic airway obstruction
morphology = mucous membrane swelling, excessive secretions, narrowing of bronchioles
symptoms = persistent cough, SOB, hypercapnia (o2 retention)


Asthma (obstructive)

chronic inflammatory disorder of the airways causing SOB, bronchoconstriction, wheezing, cough, chest tightness
partially reversible with treatment
extrinsic = response to inhaled antigen)
intrinsic = non-immune mechanism eg exercise, cold, aspirin
atopic = IgE mediated hypersensitivity
morphology = lung overinflation, thick mucous plug in bronchi


Bronchiectasis (obstructive)

permanent destruction and dilation of airways associated with severe infections and obstructions
aetiology = CF, TB, measles, bronchial obstruction
morphology = dilated, inflamed airways
symptoms = persistent cough sputum


Restrictive lung disease

xray = bilateral infiltrative lesions, small nodules, irregular lines
scarring and gross destruction of the lung = end stage/honeycomb lung
clinical features;
tachypnea, crackles, eventual cyanosis, decrease in gas diffusing capacity, lung volume and compliance
can lead to R sided heart failure


Vascular disorders - pulmonary embolism

blockage of main/branchpulmonary artery of an embolus
source of embolus are DVT of the leg
morphology = central/peripheral emboli, pulmonary haemorrhage/infarction
symptoms = pleuritic chest pain, SOB, hypoxia, increased pulmonary vascular resistance


Vascular disorders - pulmonary oedema

accumulation of fluid in the air space and parenchyma of the lungs
haemodynamic oedema = increased venous pressure eg L ventricular failure
morphology = initial fluid accumulation
engorged alveolar capillaries, pink precipitate
heavy, wet lungs
alveolar microhaemorrhages
symptoms = SOB, pink sputum


What are the 2 types of respiratory failure

Type 1: hypoxia with normal/low PCO
> pneumonia
> pulmonary oedema
> asthma
> pulmonary fibrosis
Type 2: hypoxia with high PCO2
> asthma/COPD/OSA
> decreased pulmonary drive
> neuromuscular disease
> thoracic wall disease