Introduction to respiratory system disease

Introduction to Respiratory System

Development of the lungs
Classification of lung problems
Important symptomatology

Classification

Anatomical

Interstitial lung diseases

Pleural diseases
Airways diseases

Physiological

Obstructive (COPD,asthma, and bronchiectasis)
Limitation of airflow

Restrictive(Idiopathic pulmonary fibrosis)

Decreased lung compliance and small lung volumes
Classification cont

Classification cont

Pulmonary vascular diseases( increased pulmonary vascular resistance)
Obstruction to blood flow as a result of blood clots (e.g., pulmonary embolus)
Blood vessels abnormal changes (e.g., pulmonary arterial hypertension).


Classification cont
Disorders of respiratory control (extrapulmonary abnormalities causing abnormal ventilation)
Sleep disorders as obstructive sleep apnea
Neuromuscular system disorders such as myasthenia gravis and polymyositis

Symptoms

A Detailed History and Review of Symptoms.

Dyspnea ( Shortness of Breath)

A common complaint of respiratory and non respiratory problems

Timing and acuity of onset

Exacerbating and alleviating factors
Degree of functional impairment
Associated symptoms
Environmental triggers


Recent, of sudden onset, and accompanied by chest pain
(pneumothorax, pulmonary embolism, and pulmonary edema )

Slowly progressive

(chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, pulmonary arterial hypertension, and neuromuscular disorders )

Orthopnea is dyspnea that occurs in the supine position( Heart failure and abdominal distension pressing on the diaphragm
Paroxysmal nocturnal dyspnea (1 to several hours after lying down :congestive heart failure)
Nocturnal worsening occurs also in asthma (Early Morning Dipping)
Exercise-induced asthma causes dyspnea 15 to 30
minutes after the cessation of exercise.

Wheezing

Important symptom of asthma

Other conditions congestive heart failure; endobronchial obstruction by tumor, foreign body, or mucus; and acute bronchitis.

Cough

The most common cause of acute cough is acute bronchitis

The three most common causes of chronic cough are postnasal drip, asthma, and gastroesophageal reflux disease.


Cough May be mild and infrequent, or it may be severe enough to induce emesis or syncope.

Cough may be dry or may produce sputum or blood (i.e., hemoptysis).

Long lasting dry irritative cough occur in those taking angiotensin-converting enzyme [ACE] inhibitors and Bordetella pertussis infection (i.e., whooping cough) and viral lower respiratory tract infections and occationaly in asthma(cough-variant asthma)

Sputum

More than occasional production of sputum is abnormal

Quantity, color, timing, and presence or absence of blood

Purulent sputum usually means a bacterial infection but can be seen in inflammatory conditions

Hemoptysis

Is a very important symptom.
The volume may be scant or large enough to cause asphyxiation
The most common cause is bronchitis
BUT Important causes has to be excluded as
Pulmonary tuberculosis, Pulmonary embolism and Lung malignancy
Massive hemoptysis( more than 500 mL of blood in 24 hours) is rare and is an emergency state


Chest pain
Usually results from pleural disease, pulmonary vascular disease, or musculoskeletal system because no pain receptors exist in the lung parenchyma.

Lung cancer, for example, does not cause pain until it invades the pleura, chest wall, vertebral bodies, or mediastinal structures.

Pleuritic chest pain characterized as a sharp or stabbing pain with deep inspiration(pulmonary emboli, infection, pneumothorax, and collagen vascular disease ).

Past History

History of pneumonia, tuberculosis, or chronic bronchitis,

previous X ray reports .

Patients with the acquired immunodeficiency syndrome (AIDS) are at high risk for Pneumocystis jiroveci pneumonia and tuberculosis.

Immunosuppression from long-standing steroid use may predispose to tuberculosis and other lung infections.

Drug History

Lung toxicity can result from many therapeutic actions

Pulmonary embolism from use of the oral contraceptive pill,

Interstitial lung disease from cytotoxic agents (e.g.,methotrexate, cyclophosphamide, bleomycin),

Bronchospasm from β-adrenergic receptor blockers or nonsteroidal antiinflammatory drugs

Cough from ACE inhibitors.

Enviromental history
Tobacco smoke is the most prevalent environmental toxin causing lung disease

Occupational history

Travel history

Family History

Important in assessing the risk for genetic lung diseases such as cystic fibrosis and α1-antitrypsin deficiency and susceptibility to asthma, emphysema, or lung cancer.