Emphysma. A condition of lower respirator system.

Emphysema is a chronic lung condition characterized by damage to the air sacs (alveoli) in the lungs, leading to shortness of breath and reduced oxygen exchange.

1. EMPHYSEMA By MUTEGEKI ADOLF

2. Learning Objectives By the end of this lecture, learners should be able to: Define Emphysma Describe the Pathophysiology of Emphysma Explain Classes of Emphysma Outline Causes Emphysma Make Diagnosis and Treat a patient presenting with Emphysma State Preventive measures for Emphysma

3. Definition: Emphysema is a chronic, progressive lung condition characterized by the destruction of the alveoli, the tiny air sacs in the lungs where gas exchange occurs. This destruction leads to the formation of larger air spaces and reduces the surface area available for gas exchange, resulting in difficulty breathing and reduced oxygen supply to the body

4. Incidence The national health interview survey reports the prevalence of emphysemaat 18 cases per 1000 persons and chronic bronchitis at 34 cases per 1000 persons.

5. Pathophysiology In emphysema, the walls between the alveoli are damaged, causing them to lose their elasticity and become less efficient in expelling air. This results in air becoming trapped in the lungs, leading to hyperinflation. The breakdown of alveolar walls is primarily due to an imbalance between proteases (enzymes that break down proteins) and antiproteases (enzymes that protect tissues from damage) in the lungs. This imbalance is often caused by chronic exposure to harmful substances like cigarette smoke, which increases protease activity and decreases antiprotease activity, leading to tissue destruction.

6. Signs and symptoms Breathlessness with exertion or even at rest Swelling of the legs, ankles and feet Bloating of abdomen due to fluid build up Chronic cough: Often with sputum production. Wheezing Barrel chest: Increased anterior-posterior diameter of the chest due to lung hyperinflation . Weight loss Cyanosis

7. Classification Emphysema can be classified into different types based on the location and pattern of alveolar damage: 1. Centriacinar ( Centrilobular ) Emphysema: Affects the central portions of the acini (clusters of alveoli) in the upper lobes of the lungs. Most commonly associated with smoking. 2. Panacinar ( Panlobular ) Emphysema: Affects the entire acinus , typically in the lower lobes. Often associated with alpha-1 antitrypsin deficiency, a genetic disorder. 3. Paraseptal Emphysema: Affects the distal part of the acinus , usually near the pleura (outer lining of the lung). Can be associated with spontaneous pneumothorax. 4. Irregular Emphysema: Characterized by irregular involvement of the acinus , often associated with scarring. Not a specific pattern and often found incidentally.

8. Risk factors/ Causes Smoking: The leading cause of emphysema, accounting for the majority of cases. Air pollution: Long-term exposure to air pollutants can contribute to lung damage. Occupational exposure: Inhalation of dust, chemicals, or fumes in certain work environments. Genetic factors: Alpha-1 antitrypsin deficiency is a genetic disorder that increases the risk of developing emphysema, particularly in non-smokers. Aging: Age-related changes in lung tissue may contribute to the development of emphysema.

9. Diagnostic evaluation 1. History taking and physical examination 2. Lung function tests : Spirometry : Measures the amount of air a person can inhale and exhale, and how quickly they can exhale. Key findings in emphysema include: Reduced FEV1 (Forced Expiratory Volume in 1 second): A hallmark of obstructive lung diseases. Reduced FEV1/FVC ratio (Forced Vital Capacity): Typically below 70%, indicating airflow obstruction. Increased Residual Volume (RV) and Total Lung Capacity (TLC): Due to air trapping and hyperinflation

10. Lung volumes: Measures the volume of air in the lungs at different phases of the breathing cycle. Emphysema patients often have: Increased RV and TLC: Reflecting hyperinflation. Decreased Diffusing Capacity of the Lung for Carbon Monoxide (DLCO): Indicative of impaired gas exchange due to alveolar destruction.

11. 3. Imaging Studies Chest X-ray: Can show signs of hyperinflation, such as a flattened diaphragm, increased retrosternal air space, and a long, narrow heart shadow. May show reduced vascular markings in the peripheral lung fields. High-Resolution Computed Tomography (HRCT) of the Chest: More sensitive than a chest X-ray in detecting emphysema. Can show areas of low attenuation (dark areas) due to air trapping, as well as bullae (large air-filled spaces) and destruction of lung parenchyma. Useful for assessing the type (e.g., centrilobular , panlobular ) and extent of emphysem

12. 4. Arterial Blood Gas (ABG) Analysis: Measures the levels of oxygen (PaO2), carbon dioxide (PaCO2), and blood pH. Hypoxemia (low PaO2): Common in advanced stages of emphysema. Hypercapnia (high PaCO2): May occur in severe cases due to impaired gas exchange. Respiratory acidosis: A potential finding in advanced or acute exacerbations.

13. 5. Alpha-1 Antitrypsin (AAT) Levels Serum alpha-1 antitrypsin levels: Tested in patients, especially younger ones, non-smokers, or those with a family history of emphysema to check for AAT deficiency, a genetic condition that can cause emphysema. 6 . Oximetry : Pulse oximetry : A non-invasive method to measure blood oxygen saturation (SpO2). It helps in monitoring oxygen levels in the blood, especially during exertion or sleep. 7 . Six-Minute Walk Test (6MWT) Assesses exercise tolerance and the impact of emphysema on daily activities. Measures the distance walked in six minutes and monitors oxygen levels during the test.

14. 8 . Electrocardiogram (ECG) and Echocardiography ECG: Used to assess the impact of emphysema on the heart, especially to detect signs of right heart strain ( cor pulmonale ) due to pulmonary hypertension. Echocardiography: Can assess the function and size of the right ventricle, and check for pulmonary hypertension. 9 . Sputum Analysis: To identify bacterial infections that might cause exacerbations of chronic obstructive pulmonary disease (COPD), which includes emphysema.

15. Complications Collapsed lung (pneumothorax): Heart problems Bullae (Large holes in the lungs) Pulmonary Hypertension Respiratory Failure

16. Management The management of emphysema primarily focuses on relieving symptoms, preventing complications, and slowing disease progression 1. Bronchodilators Short-Acting Beta-2 Agonists (SABAs) Example: Albuterol (Salbutamol) Long-Acting Beta-2 Agonists (LABAs) Example: Salmeterol Short-Acting Muscarinic Antagonists (SAMAs) Example: Ipratropium Long-Acting Muscarinic Antagonists (LAMAs) Example: Tiotropium

17. Anticholinergic e.g Atropine Cortical steroids e.g Prednisolone Mast cell stabilizers e.g cromolyn sodium Xanthine Derivatives e.g theophylline, Aminophylline Oxygen therapy: For patients with severe hypoxemia (low blood oxygen levels). Pulmonary rehabilitation: A program of exercise, education, and support to help patients manage their symptoms .

18. Surgical interventions: Lung volume reduction surgery (LVRS): Removal of damaged lung tissue to improve lung function. Lung transplantation: For patients with end-stage emphysema who are suitable candidates. Management of exacerbations: Prompt treatment of respiratory infections and exacerbations with antibiotics, steroids, and bronchodilators.

19. Prevention Avoid smoking: The most effective way to prevent emphysema is to avoid smoking or quit if you currently smoke. Avoid exposure to lung irritants: Limit exposure to air pollution, chemical fumes, and dust. Protective equipment: Use masks or respirators if working in environments with lung irritants. Regular vaccinations: Get vaccinated against influenza and pneumococcal pneumonia to reduce the risk of respiratory infections. Early detection and management: Regular check-ups, especially for those at risk, to detect and manage the condition early.

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