DiseasesDiseases of of

RESPIRATORY RESPIRATORY SYSTEMSYSTEM

Chronic Obstructive Chronic Obstructive Pulmonary DiseasesPulmonary Diseases

Definition:Definition: A group of pulmonary diseases A group of pulmonary diseases

characterized by increased resistance characterized by increased resistance to air flow due to partial or complete to air flow due to partial or complete obstruction at any level.obstruction at any level.

Types: Types: 1. Chronic bronchitis. 1. Chronic bronchitis.

2. Bronchial asthma. 2. Bronchial asthma.

3. Emphysema.3. Emphysema.

(l) Chronic Bronchitis(l) Chronic BronchitisDefinition:Definition: It is persistent productive cough for It is persistent productive cough for

at least 3 consecutive months in at at least 3 consecutive months in at least 2 consecutive years. least 2 consecutive years.

Common in middle-aged menCommon in middle-aged men

Causes:Causes:

1- Cigarette smoking. 1- Cigarette smoking.

2- Atmospheric pollution 2- Atmospheric pollution

3- Chronic inflammation of upper 3- Chronic inflammation of upper respiratory tract.respiratory tract.

Pathology:Pathology:..N/E:N/E: Bronchial mucosa appears thick, opaque and Bronchial mucosa appears thick, opaque and

covered by excess mucous.covered by excess mucous.M/P:M/P:both bronchi and bronchioles show;both bronchi and bronchioles show;1) Epithelium: 1) Epithelium: - Goblet cell hyperplasia. - Goblet cell hyperplasia. - Squamous metaplasia and dysplasia. - Squamous metaplasia and dysplasia. 2) Subepithelial Tissue:2) Subepithelial Tissue: - Chronic inflammatory cell infiltrations. - Chronic inflammatory cell infiltrations. - Hyperplasia of mucous glands. - Hyperplasia of mucous glands. - Fibrosis.- Fibrosis.

Complications:Complications: 1- Centrilobular emphysema. 1- Centrilobular emphysema. 2- Bronchopneumonia.2- Bronchopneumonia.3- Malignancy: Bronchogenic carcinoma.3- Malignancy: Bronchogenic carcinoma.4- Pulmonary hypertension and 4- Pulmonary hypertension and

corpulmonale.corpulmonale.5- Heart failure.5- Heart failure.

(2) Bronchial Asthma(2) Bronchial AsthmaDefinition:Definition:

episodes of reversible bronchospasm resulting episodes of reversible bronchospasm resulting from increased responsiveness of the bronchial from increased responsiveness of the bronchial

tree to various types of stimuli.tree to various types of stimuli.

Aetiology and Types:Aetiology and Types:

1. Extrinsic (immunological, atopic, 1. Extrinsic (immunological, atopic, allergic) asthma.allergic) asthma.

2. Intrinsic asthma (non-immunological, 2. Intrinsic asthma (non-immunological, non-allergic).non-allergic).

Extrinsic asthma Extrinsic asthma Intrinsic asthma Intrinsic asthma

1. Age 1. Age

children & young adults. children & young adults. adults. adults.

2. Etiopathognesis2. Etiopathognesis

- Atopy (type I - Atopy (type I hyperesensitivity reaction) hyperesensitivity reaction) due to exposure to exogenous due to exposure to exogenous non-bacterial antigens e.g. non-bacterial antigens e.g. house dust, animal dandruff, house dust, animal dandruff, pollens, food or spores of pollens, food or spores of fungi.fungi.

- Positive family history of - Positive family history of atopic diseases. atopic diseases.

- Due to increased air ways - Due to increased air ways reactivity to vagal reactivity to vagal stimulation in response to stimulation in response to various types of stimuli e.g. various types of stimuli e.g. infections (especially viruses), infections (especially viruses), exposure to cold, physical exposure to cold, physical exercise, anxiety, emotions, exercise, anxiety, emotions, aspirin.aspirin.

- No family history of similar - No family history of similar cases. cases.

3. Prognosis3. Prognosis

GoodGoodBadBad

* N/E: * N/E: Small bronchi and Small bronchi and

bronchioles are spastic bronchioles are spastic (thick and narrow).(thick and narrow).

Trachea & bronchi are Trachea & bronchi are hyperaemic and covered by hyperaemic and covered by mucus.mucus.

Lung tissue shows Lung tissue shows emphysematous changes emphysematous changes (due to partial bronchial (due to partial bronchial obstruction).obstruction).

* M/P:* M/P: The small bronchi and bronchioles The small bronchi and bronchioles

show; show;

1. Thick basement membrane 1. Thick basement membrane

2. Narrow lumens, contains2. Narrow lumens, contains mucus plugs mucus plugs which contain whorls of sheded epithelial which contain whorls of sheded epithelial cells cells ((curschmann spiralscurschmann spirals),), numerous numerous eosinophils and eosinophils and charcot-leyden crystalscharcot-leyden crystals (esinophil membranes).(esinophil membranes).

3. The subepithelial tissue show; 3. The subepithelial tissue show; • Hyperplasia of mucous glands.Hyperplasia of mucous glands.• Hypertrophy of the smooth muscle.Hypertrophy of the smooth muscle.• Inflammatory infiltrate formed mainly of Inflammatory infiltrate formed mainly of

eosinophils.eosinophils.

Complications: Complications:

1.1. PPulmonary hypertension: causing Core ulmonary hypertension: causing Core pulmonale or heart failure.pulmonale or heart failure.

2.2. EEmphysema.mphysema.

3.3. BBacterial infection causing persistent acterial infection causing persistent bronchitis, bronchiectasis or pneumonia.bronchitis, bronchiectasis or pneumonia.

4.4. SStatus asthmaticus: persistent attacks tatus asthmaticus: persistent attacks for days or weeks. May lead to for days or weeks. May lead to respiratory failure.respiratory failure.

(3) Emphysema(3) Emphysema

Definition:Definition: Permanent dilatation of air spaces Permanent dilatation of air spaces

distal to the terminal bronchioles distal to the terminal bronchioles accompanied by damage of their accompanied by damage of their walls.walls.

Respiratory acinusRespiratory acinus Respiratory bronchioles + Respiratory bronchioles +

alveolar ducts + alveolialveolar ducts + alveoli..

* Types* Types

1.1. Centriacinar (centrilobular) Centriacinar (centrilobular) emphysemaemphysema

2.2. Panacinar (panlobular) Panacinar (panlobular) emphysemaemphysema

Centriacinar Centriacinar (centrilobular) (centrilobular)

emphysemaemphysema

Panacinar Panacinar (panlobular) (panlobular) emphysemaemphysema

1. Site of involvement1. Site of involvement

Central part of the Central part of the respiratory acinus respiratory acinus

(respiratory (respiratory bronchiole)bronchiole)

the whole respiratory the whole respiratory acinusacinus

((RB+AD+alveoliRB+AD+alveoli))

Centriacinar Centriacinar (centrilobular) (centrilobular) emphysema emphysema

Panacinar Panacinar (panlobular) (panlobular) emphysema emphysema

2. Pathogenesis2. Pathogenesis Related to cigarette Related to cigarette

smoking, explained smoking, explained by;by;

Elastase-antielastase Elastase-antielastase imbalance theory:imbalance theory:

Chronic bronchitis Chronic bronchitis

theory: theory:

Releated to congential Releated to congential defeciency of defeciency of antielastase (congenital antielastase (congenital αα 1 antitrypsin 1 antitrypsin defeciency). defeciency).

Centriacinar Centriacinar (centrilobular) (centrilobular) emphysema emphysema

Panacinar (panlobular) Panacinar (panlobular) emphysema emphysema

3. N/E3. N/E Upper lobes are first Upper lobes are first

affected.affected. Moderate lung Moderate lung

enlargement.enlargement. C/S: clusters of dilated C/S: clusters of dilated

air spaces.air spaces.

11. Chest: Barrel-shaped . Chest: Barrel-shaped chest: chest: Increased Increased anteroposterior anteroposterior diameter.Horizontal diameter.Horizontal ribs.Wide subcostal angle.ribs.Wide subcostal angle.

2. Lungs: 2. Lungs: Lower lobes of the lungs Lower lobes of the lungs are first affected.are first affected.Markedly enlarged Markedly enlarged lungs.lungs.Very light. Very light. Pale. Pale.

Centriacinar Centriacinar (centrilobular) (centrilobular) emphysema emphysema

Panacinar Panacinar (panlobular) (panlobular) emphysema emphysema

Consistency: soft and Consistency: soft and pit on pressure.pit on pressure.Smooth outer surface Smooth outer surface with evident rib with evident rib markings.markings.Emphysematous bullae: Emphysematous bullae: coalescent wide air coalescent wide air spaces along weak spaces along weak borders e.g. apex, borders e.g. apex, anterior margin and free anterior margin and free edge of the base).edge of the base).C/S: diffuse areas of C/S: diffuse areas of large air spaces.large air spaces.

Centriacinar Centriacinar (centrilobular) (centrilobular) emphysema emphysema

Panacinar Panacinar (panlobular) (panlobular) emphysema emphysema

4. M/P4. M/P Dilated respiratory Dilated respiratory

bronchioles only with bronchioles only with normal alveolar ducts normal alveolar ducts and alveoli.and alveoli.

1. Alveoli are:1. Alveoli are:

- Few in number, - Few in number, increased in size, increased in size, distorted in shape.distorted in shape.

- Some alveolar septa - Some alveolar septa rupture and the alveolar rupture and the alveolar lumens coalesce to each lumens coalesce to each other.other.

2. Alveolar walls are:2. Alveolar walls are: thin with compressed thin with compressed capillaries and capillaries and arterioles.arterioles.

Centriacinar Centriacinar (centrilobular) (centrilobular) emphysema emphysema

Panacinar Panacinar (panlobular) (panlobular) emphysema emphysema

5. Complications5. Complications

I. Respiratory system:I. Respiratory system:1.1. Chronic bronchitis.Chronic bronchitis.

2.2. Air embolism.Air embolism.

3.3. Spontinous pneumothorax (due to rupture of Spontinous pneumothorax (due to rupture of emphysematous bulla).emphysematous bulla).

4.4. Respiratory failure.Respiratory failure.

II. C.V.S: II. C.V.S: Pulmonary hypertension & Pulmonary hypertension & Rt.sided heart failure. Rt.sided heart failure.