Chronic Obstructive Pulmonary Disease (COPD)

•  COPD (Chronic Obstructive Pulmonary Disease) is a disease state characterized by airflow limi­tation that is not fully.reversible.
• The airflow limitation is usually both progressive and associated with an abnormal inflammatory response of the lungs to noxious (toxic) particles or gases.
• The Global initiative for Chronic Obstructive Lung Dis­ease (GOLD) defines COPD as a limitation of air flow which is not reversible.
• This includes emphysema, chronic bronchitis, and small airway disease. In all these, chronic airflow 05­struction occurs.
  •  Emphysema is the destruction and enlargement of
  • alveoli.
  • Chronic bronchitis is a condition with chronic cough and ex ectoration.
  • Small airway disease is a condition in which small broncioles are narrowed.

Risk factors of COPD

• Cigarette smoking
• Tendency for bronchoconstriction – allergic, environmental, genetic factors
• Respiratory infection
• Occupational exposures
• Air pollution
• Passive smoker.
• Smoking
• Passive smoking, especially adults whose parents smoked
• Severe viral pneumonia early in life
• Aging
• Alcohol consumption
• Airway hyperactivity

Stages of COPD GOLD staging by spirometric assessment —

• Measure the maximal volume of air forcibly exhaled from the point of maximum inhalation (FVC _ forced vital capacity).
• Measure volume of air exhaled during 1^st second of the maneuver (forced expiratory volume in one sec­ond) – FEV1
• Calculate ratio of FEV₁ / FVC.
• Post bronchodilator FEV₁ <80% of predicted value and FEV₁ / FVC <70% is an airflow limitation which is not fully reversible.
• Old
  • 0 – At risk
  • I – Mild
  • II – Moderate
  • III – Severe
• New:
  • 0 –
    • At risk
    • Chronic symptoms
    • Exposure to risk factors
    • Normal spirometry
  • I –
    • Mild
    • FEV₁/ FVC <70%
    • FEV₁ ~80 %
    • With or without symptoms
  • II –
    • Moderate
    • FEV₁/ FVC <70%
    • 50%.$. FEV₁ <80%
    • With or without symptoms
  • III –
    • Severe
    • FEV₁/ FVC <70%
    • 30%.$. FEV₁ <50%
    • With or without symptoms
  • IV –
    • Very severe
    • FEV₁/ FVC <70%
  • FEV₁ <30% or FEV₁ <50% predicted plus chronic respiratory failure

Pathophysiology COPD

• Impaired gas (CO₂ and O₂) exchange
• Airway obstruction by mucus in chronic bronchitis
• Destruction of lung parenchyma in emphysema
• There is mucus hypersecretion ciliar dysfunction, airflow limitation, pulmonary hyperinflation, gas ex­shange abnormalities, pulmonary hypertension, and cor pulmonale.

COPD Pathological Findings

• Chronic bronchitis

  • Bronchial mucous gland enlargement
  • Increased number of secretory cells in surface epithelium
  • Thickened small airways from edema and inflammation
  • Smooth muscle hyperplasia
  • Mucus plugging
  • Bacterial colonization of airways

• Emphysema

  • Entire lung affected
  • Bronchi usually clear of secretions
  • Anthracotic pigment
  • Alveoli enlarged with loss of septa
  • Cartilage atrophy
  • Bullae

In advanced COPD

• QLPU momnale I.e. right heart failure may develop
• There IS hypoxaemia and later on hypercapnia. In some patients. The JVP will be raised, there will be
• Pulmonary hyperte~sion, which develops late in the edema, congested liver, right ventricular 53 ascites
• course of COPO is the ma)or cardiovascular compli- signs of pulmonary hypertension. ‘ ,
• cation of CO PO and is associated with the develop- Clubbing is not a feature of COPD.
• ment of cor pulmonale and a poor prognosis.

Host Factors

• if Hereditary deficiency of alpha 1 antitrypsin Airway hyper-responsiveness
•   Lung growth

Clinical features Symptoms COPD

• Cough with expectoration
• Exertional dyspnoea and dyspnoea at rest.
• Patient uses accessory muscles of respiration there­fore any activity where the arms are to be raised above shoulder level cause discomfort or are even impos­sible.
• There may be acute exacerbations off and on need­ing hospitalizption.

COPD Physical findings

• There may be nothing particular in the physical ex­amination.
• Evidence of smoking like nicotine stains on finger tips and lips may be seen.
• There is barrel-shaped chest.
• Accessory muscles of respiration are seen to work like in the neck and abdomen.
• There is cyanosis in the lips and nails.
• On auscultation, the expiration is prolonged and there is wheezing.
• If there is predominent emphysema and no cyanosis­the patient is referred to as pink puffers.
• Pink puffers have diminished” breath sounds.
• In cigarette smokers there is centriacinar emphysema and in alphal AT deficiency there is panacinar em­physema.
• Patient with chronic bronchitis are called blue bloat­ers because of edema and cyanosis on face.
• There is weight loss.
• There is paradoxical inward movement of rib cage with inspiration called Hoover’s sign.

Diagnostic Tests & Interpretation

Lab Initial Lab Tests

• Chronic bronchitis:

  • Arterial blood gases (ABGs) may show hypercapnia and hypoxia.
  • Hemoglobin may be increased.

• Emphysema:

  • Normal serum hemoglobin or polycythemia
  • Normal PaCO₂ on ABGs

Lab diagnosis

• Spirometry-FEV₁, FEV/FVC Arterial blood gases-pH, PC02 X-Ray Chest for lungs
• Chronic bronchitis chest x-ray (CXR): Increased bronchovascular markings and cardiomegaly
• Emphysema CXR: Small heart, hyperinflation, flat diaphragms, and possibly bullous changes
• CT scan
• Serum alphal anntitrypsin