Obstructive Lung Disorders Flashcards
Which side of lung have more tendency of foreign body to enter
Right lung
Most common location of lung abscess
Right lower lobe
Most common cause of Lung abscess
Aspiration of foreign body
Most common aspirated foreign body
Food particles
Most common causative organism of Lung abscess
Anaerobes
If lung abscess seen in elderly patients, what should we rule out first
Ruleout lung cancer
If presence of multiple of lung abscesses we should rule out
Staph. Aureus Septicimea
Respiratory Epithelial lining
Pseudostratified ciliated columnar epithelium except Vocal cords
Epithelial lining of vocal cords
Stratified Squamous epithelium
Epithelial lining of vocal cords
Stratified Squamous epithelium
Cilia + Mucus are
Protective in nature
Decreased activity of cilia and mucus clearance can leads to
Increased risk of infection
Congenital disease leading to cilia dysfunction
Kartagener Syndrome
In Kartagener Syndrome, there is defect of
Dynein
Classical triad seen in Kartagener Syndrome
Bronchiectasis
Sinusitis
Situs inversus (Dextrocardia)
Acquired cause which affects cilia activity
Smoking
In Cystic fibrosis there is problem of which gene
CFTR Gene
Problem of CFTR gene in Cystic fibrosis can leads to
Chloride channel defect - Cl, Na, H20 Can’t move properly - mucus dries - mucus can’t move - increased risk of infection
Important parameters of lung
Ventilation
Perfusion
Ventilation perfusion ratio
Ventilation is most in which part of lung
Base
Perfusion is most in which part of lungs
Base
Ventilation perfusion ratio is most in which part of lungs
Apex
Normal range of Ventilation perfusion ratio
0.8
Can’t exceed 1
Wall of respiratory tract consist of
Epithelial lining
Smooth muscle
Mucus secreting cells
Cartilage
In Bronchioles there is absence of
Cartilage
Submucous glands
Reid’s index =
A/B where,
A- thickness of mucus glands
B- distance between epithelium and cartilage
Normal value of Reid’s index
0.4
Functional unit of lungs
Acinus
Types of Pneumocytes
Type 1 and
Type 2
Function of Type 1 Pneumocytes
Lines the alveolar cells and increases surface area
Function of Type 2 Pneumocytes
More in number
Secrets surfactants - decreases surface tension - important at time of expiration - prevents collapse of alveoli
Reparative function - play important role in replacement of type 1 Pneumocytes
Spirometry findings in case of Obstructive lung disorders
FEV1 <80%
FVC - Normal
FEV1/FVC - <0.7%
TLC - Normal or slightly increased
Spirometry findings in Restrictive lung disorders
FEV1 - Normal or Slightly decreased
FVC decreases
FEV1/FVC - >0.7
TLC - Decreases
Examples of Obstructive lung disorders
Emphysema
Chronic bronchitis
Bronchiectasis
Bronchial asthma
Small airway disease
Emphysema usually involves which part of lung
Disorder of acinus
Emphysema means
Abnormal permanent enlargement of air spaces distal to terminal bronchioles
Fibrosis in Emphysema
Minimal fibrosis
Alveolar wall destruction
Damaging factor of lungs in case of Emphysema
Elastase - damages elastin fibers in lungs
Protective factors of lungs in case of Emphysema
Anti-elastases - Alpha-antitrypsin, Alpha 1 macroglobulin - neutralizes Elastase
Risk factors of Emphysema
Smoking
Air pollution
Occupational hazards (Pneumoconiosis)
How Smoking can lead to emphysema
Smoking - inflammation in airways - neutrophils and macrophages increases - elastase secretion increases - damage elastin fibers of lungs - increased risk of Emphysema
Also smoking leads to formation of free radicals - decreases activity of Anti-elastase
If there is protein misfoldings in alpha 1 antitrypsin
Liver doesn’t release it in circulation - doesn’t able to reach lungs (No protective mechanism) - high risk of Emphysema or chronic bronchitis
Accumulation of misfolded proteins in liver can leads to
Micronodular Cirrhosis
Anatomical classification of Emphysema
Centriacinar emphysema
Panacinar emphysema
Distal acinar emphysema
Irregular Emphysema
Centriacinar emphysema involves which part of acinus
Involves central or proximal part of acinus
Most common cause of Centriacinar emphysema
Smoking
Clinically most common type of Emphysema
Centriacinar emphysema
Centriacinar emphysema predominantly damages which lobe of lungs
Upper lobe
Which part of acinus is affected in Panacinar emphysema
Complete acinus is affected
Panacinar emphysema is most commonly associated with
Alpha-1 anti trypsin deficiency
In Panacinar emphysema which part of lung is commonly affected
Base of lung
Which part of acinus usually affected in Distal acinar emphysema
Distal part of acinus
Distal acinar emphysema commonly affected which lobe of lungs
Upper lobe
Enlarged air spaces in emphysema can leads to
Air trapping - BLEB formation - Pneumothorax
Clinical features of Emphysema
Elderly patients (60-70 years)
Earliest complaint - Dyspnea
Use of accessory muscles
Weight loss
Pink puffers
Advanced - decreased O2 in blood - can lead to pulmonary Hypertension - Right heart failure
“Pink puffers” are referred to patients with which disease
Emphysema
Most common risk factor of Chronic bronchitis
Smoking
How Smoking can leads to Chronic bronchitis
Smoking - inflammation in airways - increase in mucus production (to remove smoke particles) - stasis of mucus - can lead to secondary infections
Reid’s index in case of Chronic bronchitis
> 0.5
Clinical features of Chronic bronchitis
Productive cough
Obese
Decreased O2 - Pulmonary HTN - Cor pulmonale
Blue Bloaters
No amyloidosis
“Blue Bloaters” referred to patients with which disease
Chronic bronchitis
COPD is combination of
Emphysema + Chronic bronchitis + Small airway disease
Treatment of COPD
Quit smoking or take Nicotine replacement
Supplemental O2 - increases longevity
Mucolytics
Ipratropium (Anticholinergic drug)
Which is reversible airway obstructive disorder
Bronchial Asthma
Airways in bronchial asthma
Hyper-responsive
Types of Bronchial asthma
Extrinsic
Intrinsic
Extrinsic bronchial asthma
Type 1 hypersensitivity reaction
External antigens - house dust, pollen
Increased IgE
Childhood onset
History of Atopy(Eczema)
Intrinsic Bronchial Asthma
No type 1 HR
Normal IgE levels
Adult onset
History of viral infection or drugs exposure
Aspirin
Samter’s Triad
Aspirin intolerance
Adult nasal polyps
Asthma
Clinical features of Bronchial Asthma
Wheezing
Dyspnea
Nocturnal cough
Diagnosis in case of Bronchial asthma
Clinical history
Spirometry
Sputum examination
Microscopic
Findings on sputum examination in case of Bronchial asthma
Curschman Spirals - zigzag structure
Charcot leyden Crystals
Creola body - degenerated airway epithelial cells
Charcot leyden Crystals are made up of
Galectin-10
Microscopic findings in case of Bronchial asthma
Airway remodeling
Increase in thickness of basement membrane (increased collagen deposition)
Hypertrophy of smooth muscle
Increased no. Of mucus glands
Eosinophilic infiltration
Gene responsible for hypertrophy of smooth muscles in Bronchial asthma
ADAM-33 gene
Marker of severity of Bronchial asthma
YKL-40
Treatment of Bronchial asthma
Avoid antigen exposure
Bronchodilators - Salbutamol,terbutaline, Formoterol
Anti-inflammatory drugs - Corticosteroids
Bronchiectasis is
Chronic necrotizing infection of airways - leads to abnormal permanent airway dilatation
Risk factors of bronchiectasis
Congenital
Obstruction
Infections
Miscellaneous conditions
Congenital causes leading to Bronchiectasis
Kartagener Syndrome
Cystic fibrosis
Obstructive risk factors of bronchiectasis
Foreign bodies or cancer
Infectious causes leading to Bronchiectasis
TB
Staph aureus
Allergic Bronchopulmonary Aspergillosis
Miscellaneous conditions leading to Bronchiectasis
Rheumatoid arthritis
Grafts vs host disease
Clinical features of Bronchiectasis
Involvement of lower lobe of lungs (Basal involvement)
Dyspnea
Bronchorrhea (cups full of sputum)
Predominantly left lung involvement
Fever
Dilated airways - can seen upto pleural surfaces
Investigation of choice in Bronchiectasis
HRCT Scan
Appearance seen in HRCT Scan in case of Bronchiectasis
Tram-Track appearance
Honey comb lungs
