Pulmonary Pathology Module 1

Where are the lungs located?

In the thoracic cavity, one on each side, separated by the mediastinum

What structures are contained in the mediastinum?

The heart, thoracic portions of the great vessels, trachea, esophagus, thymus and other structures

Why is the left lung smaller than the right lung?

The heart is rotated and positioned toward the left, encroaching on the left lung

What is the pleura?

A membrane covering the lungs

What is visceral pleura vs parietal pleura?

Visceral: adheres directly to the lung
Parietal: lines the thoracic cavity

What is the pleural cavity?

The space between the visceral and parietal pleura, normally containing a thin film of fluid

What are the main anatomical features of each lung?

Apex
Base
Three Surfaces (costal, mediastinal, diaphragmatic)
Three Borders (anterior, inferior, posterior)

What is the Apex of the lung?

Superior end of the lung that extends above the first rib

What is the Base of the lung?

The concave inferior surface that rests on the diaphragm

How many lobes does the right lung have, and what fissures divides them?

Three lobes (superior, middle, inferior) divided by the horizontal and oblique fissures

How many lobes does the left lung have and what fissures divides them?

Two lobes (superior and inferior) divided by a single oblique fissure

What is the cardiac notch?

Deep indentation on the anterior border of the left cause caused by the hearts position

What is the Lingula?

Tongue-like projection of the superior lobe of the left lung formed by the cardiac notch

Why is the Lingula clinically important?

Moves in and out of the costomediastinal recess during breathing

What is the tracheobronchial tree?

The airway system beginning at the trachea and branching into bronchi within the lungs

What structural feature supports the trachea?

C-shaped rings of hyaline cartilage

Where does the trachea bifurcate?

At the level of the transverse thoracic plane (sternal angle)

How does the right main bronchus differ from the left?

It is wider, shorter and more vertical and enters the right hilum directly

Describe the path of the left main bronchus

It passes inferiorly beneath the aortic arch and anterior to the esophagus and thoracic aorta to reach the left hilum

What are secondary (lobar) bronchi?

Branches of the main bronchi that supply each lung lobe

How many secondary bronchi are present in each lung?

Right lung: three (superior, middle, inferior)
Left lung: two (superior, inferior)

What is the bronchus intermedius?

The portion of the right main bronchus that continues inferiorly and gives rise to the middle and lower lobar bronchi

What are tertiary (segmental) bronchi?

Branches of secondary bronchi that supply individual bronchopulmonary segments

Why are bronchopulmonary segments clinically important?

They help localize lung pathology and guide auscultation and treatment

What is Chronic Bronchitis?

Long-term inflammation of the bronchial tubes (airways) in the lungs, causing excessive mucus, coughing and breathing difficulty and is a type of COPD

What causes Chronic Bronchitis?

Long-term irritation of the bronchial tubes, with cigarette smoking, air pollution and dust being causes

What is Emphysema?

A chronic lung disease, part of COPD, that destroys the tiny air sacs (alveoli) in the lungs, making it hard to breathe by trapping air and reducing oxygen exchange

What causes Emphysema?

Smoking, air pollution

What is Asthma?

A chronic inflammatory condition of the airways characterized by hyperresponsiveness of airway smooth muscle to various stimuli

How does Asthma affect the airways?

It causes widespread airway narrowing that is reversible, either spontaneously or with treatment

What are common triggers of Asthma?

Air pollution, cigarette smoke, dust, air pollution and even some medications

What are the signs/symptoms of asthma (least to most severe)?

Coughing, chest tightness, difficulty breathing, wheezing and whistling during expiration

What are the main classifications of asthma?

Intermittent
Mild Persistent
Moderate Persistent
Severe Persistent

True or False: There is a cure to Asthma

False

What environmental strategies help manage Asthma?

Avoiding or minimizing exposure to triggers through vacuuming, removing carpet/rugs and modifying environmental conditions

What medications are commonly used for acute asthma symptom relief?

Bronchodilators

How are emergency Asthma medications typically administered?

Through inhalers

How do bronchodilators improve breathing in Asthma?

They relax airway smooth muscle, causing airway dilation and improved airflow

What is Bronchiectasis?

A condition in which the bronchi and bronchioles are chronically inflamed, becoming damaged and losing their ability to clear mucus, leading to a buildup

Bronchiectasis causes damage to the mucociliary escalator. What is the mucociliary escalator?

A mechanical airway-clearing system that moves bacteria and debris out of the airways

How does chronic inflammation affect the lungs in bronchiectasis?

Elastin is destroyed and fibroblasts deposit excess collagen, resulting in stiff lungs, dilated airways and mucus plugging

What structural changes occur in the airways with bronchiectasis?

Airway becomes enlarged, less elastic and filled with mucus

What are common causes of Bronchectasis?

Long-term cigarette smoke exposure, respiratory infections and cystic fibrosis

What are common signs/symptoms of bronchiectasis?

Wheezing, productive cough, foul-smelling mucus, dyspnea, hemoptysis, recurrent pneumonia and basilar crackles

What physical finding may develop due to long-term hypoxia in bronchiesctasis?

Clubbing of the fingers and toes

How is bronchiectasis identified on imaging?

Airway changes seen on a CT scan

What are common treatments for Bronchiectasis?

Antibiotics to manage infections, and percussion and postural drainage to prevent mucus buildup

What is Restrictive Lung Disease?

A group of disorders that makes it hard for your lungs to fully expand, reducing the total amount of air they can hold, leading to shortness of breath and decreased oxygen intake

What is Pneumonia?

An infection of the lungs that results in the air sacs (alveoli) being filled with fluid

What is the most common type of Pneumonia?

Viral pneumonia, caused by the flu

What is community-acquired pneumonia?

Pneumonia that is acquired outside of the hospital, such as at home or in the community

What is hospital-acquired (nosocomial) pneumonia?

Pneumonia that develops while a patient is hospitalized for another condition

Why is hospital-acquired Pneumonia often more serious?

Patients often have weakened immune systems, and hospital microbes are frequently resistant to common antibiotics

What is ventilator-associated pneumonia?

A subset of hospital-acquired pneumonia that develops in patients who are on mechanical ventilation

Why are ventilated patients at risk for pneumonia?

A biofilm can form on the endotracheal tube, and patients cannot cough, allowing microbes to enter the lungs

What is aspiration pneumonia?

Pneumonia caused by aspiration of food, liquids or gastric contents into the lungs

Why is aspiration of gastric contents especially harmful?

Stomach acid causes chemical irritation, in addition to increasing infection risk

What is bronchopneumonia?

Pneumonia in which infection is spread throughout the lungs, involving the bronchioles and alveoli

What is atypical (interstitial) pneumonia?

Pneumonia where infection is mainly located in the interstitium, outside the alveoli

What is Lobar Pneumonia?

Pneumonia that causes complete consolidation of an entire lung love, filling it with fluid

What are common signs and symptoms of Pneumonia?

Shortness of breath, chest pain, productive cough, fever, and fatigue

How is pneumonia diagnosed?

Clinically and/or through imaging

What role does PT play in Pneumonia?

PT plays a key role in treatment, supporting airway clearance and recovery

What medications are commonly used to treat pneumonia?

Antibiotics, cough suppressants, and pain medications for symptom management

What is Pleural Effusion?

Excessive fluid accumulation in the pleural space

How does Pleural Effusion affect lung function?

It restricts full lung expansion, limiting ventilation

What conditions commonly cause Pleural Effusion?

Congestive heart failure, pneumonia, cancer, cirrhosis and kidney disease

What are the two main mechanisms that cause excess Pleural fluid?

Excess pleural fluid production or impaired lymphatic drainage

What are the three major types of Pleural Effusion?

Transudative, exudative and lymphatic pleural effusions

What is transudative pleural effusion?

Buildup of watery fluid in the pleural space caused by increased pressure in blood vessels or low protein levels, leading to fluid leakage

What causes a transudative pleural effusion?

Excess fluid leaving capillaries due to increased hydrostatic pressure or decreased oncotic pressure

Why does heart failure commonly cause transudative pleural effusion?

Blood backs up into pulmonary vessels, increasing pressure and forcing fluid into pleural space

What is exudative pleural effusion?

A buildup of protein-rich fluid in the pleural space, caused by inflammation or infection, leading to leaky blood vessels and increased fluid leakage into space

What causes an exudative pleural effusion?

Inflammation of pulmonary capillaries, making them more permeable or leaky

What conditions can cause exudative pleural effusion?

Trauma, malignancy, inflammatory diseases, and infections such as pneumonia

What is lymphatic pleural effusion?

Accumulation of lymphatic fluid due to disruption of the thoracic duct

What is the most common cause of lymphatic pleural effusion?

Accidental damage to the thoracic duct during thoracic surgery

What symptoms are associated with pleural effusion?

Symptoms depend on size. Small effusions may be asymptomatic, while large effusions cause pain, shortness of breath and worsening of symptoms when lying flat

What is Pleurisy?

Pain during inhalation caused by pleural irritation

How are large pleural effusions treated?

Therapeutic thoracentesis to remove fluid and relieve symptoms

Why is pleural fluid analyzed after thoracentesis?

To identify the underlying cause of the effusion

What additional management may be required for pleural effusion?

Treatment of the underlying condition causing the effusion

What is a Pneumothorax?

Presence of air in the pleural space due to a puncture of the pleural seal, allowing air to enter

What two opposing forces normally determine pleural pressure?

Outward pull of the chest wall and diaphragm and inward elastic recoil of the lungs

What normal pressure is created in the pleural space by these opposing forces?

A slight vacuum of approximately 5cm H2O

What happens to pleural pressure when a pneumothorax occurs?

Pressure equalizes to 0cm H2O, eliminating negative pleural pressure

Why does the lung collapse in a pneumothorax?

Loss of negative pleural pressure allows lung elastic recoil to pull the lung inward, while the chest wall moves outward

How does a pneumothorax affect gas exchange?

Collapsed lung reduces ventilation, caused decreased oxygen intake and carbon dioxide retention

What is a spontaneous pneumothorax?

A pneumothorax caused by rupture of an air pocket on the lung surface

What is a traumatic pneumothorax?

A pneumothorax caused by external trauma, such as a gunshot or stab wound

What is a tension pneumothorax?

A pneumothorax in which a one-way valve forms, allowing air to enter but not leave the pleural space

Why is tension pneumothorax especially dangerous?

Air buildup increases pressure, compressing the lungs and heart and shifting structures like the trachea away from the affected side

What are the primary symptoms of pneumothorax?

Shortness of breath and chest pain

How might a small spontaneous pneumothorax be managed?

It may be asymptomatic and can heal on its own without treatment

When does a pneumothorax require intervention?

When it is large, causes severe symptoms or is a tension pneumothorax

How is air removed in a symptomatic pneumothorax?

By inserting a needle or chest tube to allow air to escape

What is a Hemothorax?

Accumulation of blood in the pleural space

What is the most common cause of Hemothorax?

Blunt or penetrating trauma to the lungs

What structures can be the source of bleeding in a hemothorax?

Chest wall, pleura, lung parenchyma, heart or great vessels

What is an Iatrogenic Hemothorax?

When instruments damage the lung parenchyma