Pathophysiology of the Respiratory System – Review Flashcards

A comprehensive set of question-and-answer flashcards covering key developmental anatomy, physiology, clinical manifestations, obstructive and restrictive lung diseases, infections, vascular disorders, tumors, pleural pathologies, and special pediatric conditions of the respiratory system.

Who invented the stethoscope and pioneered its use in chest diagnosis?

René-Théophile-Hyacinthe Laennec in 1816.

Developmentally, from which embryologic structure does the respiratory system arise?

An outgrowth of the ventral wall of the foregut.

What structures make up a pulmonary acinus?

Respiratory bronchioles, alveolar ducts, and alveolar sacs.

Which lung has three lobes and why?

The right lung, due to branching into three lobar bronchi.

Define ventilation versus respiration.

Ventilation is mechanical movement of air; respiration is cellular gas exchange of O2 and CO2.

How is minute ventilation calculated?

Ventilatory rate × tidal volume (L / min).

What is dead-space ventilation (VD)?

The volume of air per breath that does not participate in gas exchange.

Name the three major functions of the pulmonary system.

Ventilate alveoli, diffuse gases, perfuse lungs with oxygenated blood.

Which gas is 20× more soluble in blood: O2 or CO2?

Carbon dioxide (CO2).

What arterial PaCO2 value defines hypercapnia?

44 mm Hg.

What breathing pattern is characterized by deep, rapid breathing with no expiratory pause?

Kussmaul respirations (hyperpnea).

What causes central cyanosis and where is it best observed?

Decreased arterial oxygen saturation; best seen in lips and buccal mucosa.

Define chronic cough in terms of duration.

Cough persisting for more than 3 weeks.

What is clubbing and with which condition is it commonly associated?

Bulbous enlargement of finger tips; linked to chronic hypoxemia (e.g., lung cancer).

Pulmonary hypoplasia is often fatal because of .

Defective development leading to markedly reduced lung volume and acini.

What is pulmonary sequestration?

Lung tissue with no airway connection and systemic arterial blood supply.

Hemodynamic (cardiogenic) pulmonary edema is most commonly due to .

Left-sided congestive heart failure.

Non-cardiogenic pulmonary edema results from .

Increased capillary permeability due to alveolar septal injury (e.g., ARDS).

State the PaO2/FiO2 criterion that differentiates ARDS from ALI.

ARDS ≤200 mm Hg; ALI ≤300 mm Hg.

Define obstructive lung disease.

Disease with increased resistance to airflow due to airway obstruction.

List three classic obstructive lung diseases.

Asthma, emphysema, chronic bronchitis.

Define restrictive lung disease.

Reduced lung expansion and total lung capacity due to parenchymal or chest wall disorders.

What genetic deficiency predisposes to primary emphysema?

α1-Antitrypsin deficiency (autosomal recessive).

Major mechanism of airflow limitation in emphysema?

Loss of elastic recoil causing airway collapse on expiration.

Diagnostic time requirement for chronic bronchitis?

Productive cough ≥3 months per year for ≥2 consecutive years.

Key pathologic feature of chronic bronchitis causing mucus hypersecretion?

Hypertrophy and hyperplasia of mucous glands and goblet cells.

Name two major inflammatory cell types in asthma pathogenesis.

Eosinophils and Th2 lymphocytes.

What term describes permanent dilation of bronchi due to chronic infection and obliteration of muscle and elastic tissue?

Bronchiectasis.

Silicosis increases risk for which infectious disease?

Tuberculosis (2-fold increase).

Sarcoidosis is characterized by formation of what type of granulomas?

Non-caseating granulomas.

Give two common causes of loss of lung defense leading to pneumonia.

Impaired cough reflex and damaged mucociliary apparatus.

Differentiate bronchopneumonia from interstitial pneumonia.

Bronchopneumonia: patchy, bacterial; Interstitial: diffuse alveolar wall infiltrate, viral/atypical.

What organism causes tuberculosis and how is it transmitted?

Mycobacterium tuberculosis; airborne droplets.

What is a Ghon focus/tubercle?

Granulomatous lesion with caseous necrosis in primary TB.

Define lung abscess and a common predisposing event.

Localized suppurative destruction of lung parenchyma; often follows aspiration (e.g., in alcohol abuse).

Most pulmonary emboli originate from thrombi in the .

Deep veins of the lower leg (DVT).

Mean pulmonary artery pressure required to diagnose pulmonary hypertension?

≥25 mm Hg at rest.

Which lung cancer subtype is most associated with paraneoplastic syndromes?

Small cell lung carcinoma (SCLC).

Central hilar mass with hemoptysis in a smoker suggests which carcinoma?

Squamous cell carcinoma of the lung.

Peripheral lung tumor arising from glands is called .

Adenocarcinoma.

Define pleural effusion.

Accumulation of fluid in the pleural space.

What is the difference between transudative and exudative pleural effusion?

Transudate: watery, low protein; Exudate: high protein/WBCs due to inflammation.

Primary spontaneous pneumothorax typically occurs in which demographic?

Healthy adults aged 20-40 with apical bleb rupture.

Explain tension pneumothorax.

One-way valve air entry causes increasing intrapleural pressure, lung collapse, mediastinal shift.

What age range has peak incidence of SIDS?

2-4 months.

Name three modifiable risk factors for SIDS.

Prone sleeping position, maternal smoking during pregnancy, soft bedding overheating.

Resorption atelectasis causes mediastinal shift in which direction?

Toward the collapsed (atelectatic) lung.

Compression atelectasis shifts the mediastinum the affected lung.

Away from.

Mechanism behind pneumoconiosis-induced fibrosis?

Macrophage ingestion of dust → cytokine release → ROS and fibrogenic response.

Why is CO2 removal impaired in hypoventilation?

Alveolar ventilation is inadequate relative to metabolic CO2 production.

List two main accessory muscles of inspiration.

Sternocleidomastoid and scalene muscles.

What is the work of breathing?

Metabolic energy expended to overcome lung/chest elasticity and airway resistance.

Which congenital anomaly presents as cyst lined by respiratory epithelium in mediastinum?

Bronchogenic cyst (a foregut cyst).

What defines COPD according to GOLD?

Common, preventable, treatable disease with persistent, usually progressive airflow limitation and chronic inflammatory response to noxious particles/gases.

In COPD pathogenesis, tobacco smoke increases protease activity leading to destruction of .

Elastin in lung connective tissue.

How does emphysema appear on chest X-ray?

Hyperinflated lungs, flattened diaphragm, possible bullae (floating heart sign).

Which pulmonary edema cause is linked to high-altitude exposure?

Edema of undetermined origin (non-cardiogenic).

What ventilatory parameter falls in restrictive lung disease?

Forced vital capacity (FVC).

Case study: 65-year-old smoker, hemoptysis, central mass. Likely diagnosis?

Squamous cell carcinoma.

Case study: Young adult with dry cough, bilateral hilar lymphadenopathy. Likely diagnosis?

Sarcoidosis or Tuberculosis