Chronic obstructive pulmonary disease (COPD)

 COPD, or chronic obstructive pulmonary disease, is a progressive disease that makes it hard to breathe. "Progressive" means the disease gets worse over time.

It is a disease state characterized by airflow limitation that is not fully reversible.

COPD may include diseases that cause airflow obstruction (eg, emphysema, chronic bronchitis) or a combination of these disorders. 

Asthma was previously classified as types of chronic obstructive lung disease. 

asthma is now considered a separate disorder and is classified as an abnormal airway condition characterized primarily by reversible inflammation.

In COPD, less air flows in and out of the airways because of one or more of the following:

• The walls of the airways become thick and inflamed. 
• The airways and air sacs lose their elastic quality. 
• The walls between many of the air sacs are destroyed. 
• The airways make more mucus than usual, which tends to clog them.

1- Chronic Bronchitis

a disease of the airways, is defined as the presence of cough and sputum production for at least 3 months in each of 2 consecutive years. 

Characterized by Chronic inflammation

The most important cause is recurrent irritation of the bronchial mucosa by inhaled substances, as occurs in cigarette smokers. 

Bronchial walls thicken

• Bronchial Lumen narrows by increase in the size of the bronchial mucus glands
• Mucus plugs airway lead to obstruction

Plugs become areas for bacteria to grow and chronic infections which increases mucus secretions and eventually, areas of focal necrosis and fibrosis

Alveoli/bronchioles become damaged

2- Emphysema

Defined as destruction of the alveoli that deliver oxygen into the lung and remove the carbon dioxide.

Characterized by Chronic cough

Types of Emphysema

In the panlobular type

• There is destruction of the bronchiole, alveolar duct, and alveoli. All air spaces within the lobule are essentially enlarged. 
• The patient with this type of emphysema typically has a hyper inflated chest (barrel chest on physical examination), marked dyspnea on exertion, and weight loss.

In the centrilobular form,

• pathologic changes take place mainly in the center of the lobule, producing chronic hypoxemia, hypercapnia (increased CO2 in the arterial blood).

Pathophysiology of emphysema

• Affects alveolar membrane 
• Destruction of alveolar wall 
• Loss of elastic recoil 
• Over distended alveoli 
• → Impaired gas exchange 
• Hypoxemia 
• h CO2 →

Risk Factors of COPD

• Smoking irritates the mucus glands, causing an increased accumulation of mucus, which in turn produces more irritation, infection, and damage to the lung. 
• Smoking depresses the activity of the respiratory tract’s ciliary cleansing mechanism. 
• In addition, carbon monoxide (a byproduct of smoking) combines with hemoglobin to form carboxyhemoglobin that cannot carry oxygen efficiently. 
• Deficiency of alpha1 antitrypsin, an enzyme inhibitor that protects the lung parenchyma from injury. 

Sysmptoms

• cough 
• sputum
•  dyspnea

Complications

• Hypoxemia may further increase pulmonary artery pressure. 
• Right-sided heart failure (cor pulmonale) is one of the complications of emphysema 
• Congestion, dependent edema, distended neck veins, or pain in the region of the liver suggests the development of cardiac failure. 

Diagnostic Findings

• Pulmonary function tests are used to help confirm the diagnosis of COPD, 
• Arterial blood gas 
• chest x-ray 
• alpha1 antitrypsin deficiency screening may be performed for patients under age 45 or for those with a strong family history of COPD. 

PHARMACOLOGIC THERAPY

Bronchodilators. To relieve bronchospasm To reduce airway obstruction To increase oxygen distribution throughout the lungs and improving lung ventilation

Corticosteroids. Inhaled and systemic corticosteroids (oral or intravenous) Examples of corticosteroids in the inhaled form are beclomethasone (Beclovent, Vanceril), budesonide (Pulmicort), flunisolide (AeroBid), fluticasone (Flovent), and triamcinolone (Azmacort). 

Influenza vaccine and the pneumococcal vaccine every 5 to 7 years as preventive measures.

Alpha1 antitrypsin augmentation therapy,

Antibiotic , mucolytic agents

OXYGEN THERAPY 

Oxygen therapy can be administered as long-term continuous therapy, during exercise, or to prevent acute dyspnea. Long term oxygen therapy has been shown to improve the patient’s quality of life and survival

Oxygen therapy can be administered as long-term continuous therapy, during exercise, or to prevent acute dyspnea. Long term oxygen therapy has been shown to improve the patient’s quality of life and survival

SURGICAL MANAGEMENT

Lung Volume Reduction Surgery.

• It involves the removal of a portion of the diseased lung parenchyma. 
• This allows the functional tissue to expand, resulting in improved elastic recoil of the lung and improved chest wall and diaphragmatic mechanics. 

Lung Transplantation

• Surgical treatment for the end-stage of emphysema. It has been shown to improve quality of life and functional capacity

Breathing Exercises

Diaphragmatic breathing

• To reduces the respiratory rate, 
• To increases alveolar ventilation, 
• To expel as much air as possible during expiration. 

Pursed lip breathing

• To slow expiration, 
• To prevent collapse of small airways. 
• To control the rate and depth of respiration.