COPD.pptx

Bronchial Asthma • Asthma is a common chronic inflammatory condition of the lung airways whose cause is incompletely understood. • Symptoms • cough, • wheeze, • chest tightness • Dyspnea , It has three characteristics · Airflow limitation which is usually reversible spontaneously or with treatm...

Bronchial Asthma • Asthma is a common chronic inflammatory condition of the lung airways whose cause is incompletely understood. • Symptoms • cough, • wheeze, • chest tightness • Dyspnea , It has three characteristics · Airflow limitation which is usually reversible spontaneously or with treatment · Airway hyper-responsiveness to a wide range of stimuli. Infiltration of the bronchi with eosinophils, T lymphocytes and mast cells with associated plasma exudation, edema, marked smooth muscle hypertrophy, mucus plugging and epithelial damage. Prevalence • In many countries the prevalence of asthma is increasing, particularly in the second decade of life • There is also a geographical variation, with asthma being common in more developed countries Classification extrinsic intrinsic Extrinsic • Has a definite external cause. • Occurs most frequently in atopic individuals who show positive skin-prick reactions to common inhalant allergens, • +ve family history of allergy, • usually high serum level of Ig E. Intrinsic • when no causative agent can be identified • often starts in middle age ('late onset'). • Family history of allergy is often - ve, • the serum level of Ig E is not raised Etiology Asthma is a heterogeneous disease with interplay between genetic and environmental factors. • Genetic predisposition, Atopy, Airway hyperresponsiveness, Ethnicity and Gender. • Environmental Factors: Occupational sensitizers, Indoor allergens, Outdoor allergens, Passive smoking, Respiratory infections. Pathology • The airway mucosa is infiltrated with activated eosinophils ,T lymphocytes, and mast cells. • Thickening of the basement membrane due to subepithelial collagen deposition. Pathology • The epithelium is often shed or friable, with reduced attachments to the airway wall and increased numbers of epithelial cells in the lumen Pathology • Sub mucosa is edematous and infiltrated with eosinophils , lymphocytes and mast cells with dilated capillaries. • Muscles are hypertrophied. • Mucus glands are enlarged Clinical features: • The principal symptoms of asthma are wheezing attacks and episodic shortness of breath. • Symptoms are usually worst during the night. • Cough is a frequent symptom that sometimes predominates and is often misdiagnosed as bronchitis. • May be normal (in between the attacks). Investigations Respiratory function tests • Total lung capacity (TLC): Volume of gas in lung after maximal inspiration. • Functional Residual Capacity (FRC): Volume of gas in lung at the end of normal expiration. • Residual volume: Volume of gas remaining in lung after maximal expiration (RV) • Expiratory reserve volume: Difference between FRC and RV. • Forced Vital Capacity (FVC): Volume of gas that can be forcefully exhaled from lungs after maximal inspiration • Forced expiratory volume in 1 second (FEV1): Volume of gas exhaled in first second of FVC manoeuver. Blood and sputum tests CBC :Patients with asthma may have an increase in the number of eosinophils in peripheral blood (> 0.4 × 109/L). Sputum examination : The presence of large numbers of eosinophils in the sputum is a more useful diagnostic tool. Chest X-ray: •over inflation is characteristic during an acute episode or in chronic severe disease. •A chest X-ray may be helpful in excluding a pneumothorax, which can occur as a complication. Skin tests: Skin-prick tests should be performed in all cases of asthma to help identify allergic causes. Management The aims of treatment are to: • Abolish symptoms • Restore normal or best possible lung function • Reduce the risk of severe attacks • Enable normal growth to occur in children • Minimize absence from school or employment. • Use of short-acting inhaled bronchodilators (e.g. salbutamol and terbutaline) only to relieve symptoms. • Increased use of bronchodilator treatment to relieve increasing symptoms is an indication of deteriorating disease. • Inhaled oral steroids short-acting relievers (beclometasone , budesonide ) • Long-acting relief/disease controllers. - Long-acting β2 agonists • Other agents with bronchodilator activity Antimuscarinic agents (ipratropium, oxitropium),Theophylline preparations Treatment of severe asthma • Nebulized salbutamol 5 mg or terbutaline 10 mg is administered. • Hydrocortisone sodium succinate 200 mg i.v. is given. • Oxygen 40-60% is given if available. • Prednisolone 60 mg is given orally. The patient is reassessed Measure O2 saturation with a pulse oximeter. • Arterial blood gases are measured ; • if the Paco2 is significantly increased or • If sever hypoxemia developed ventilation should be considered. Complications of asthma: • 1 Respiratory failure. • 2 Pneumothorax • 3 Retardation of growth. COPD Chronic Obstructive Pulmonary Disease • Chronic slowly progressive disease characterized by airflow obstruction • Currently 4th commonest cause of death worldwide Etiology • Smoking ( usually history of 20 pack /year the disease is progressive even after cessation of smoking. • Air pollution • Low birth weight • Dust exposure • Alpha-1-antitrypsin deficiency. Pathology and pathogenesis: COPD is a combination of chronic bronchitis and emphysema Chronic bronchitis is chronic cough and sputum production for at least 3 months of 2 consecutive years in absence of other diseases causing productive cough Mucus hyper secretion from the bronchi due to gland hypertrophy and increased goblet cells. Emphysema abnormal permanent enlargement of air spaces distal to terminal bronchioles, accompanied by destruction of walls without obvious fibrosis. Manifestations: symptoms: • Dyspnoea (shortness of breath) • Cough • Wheezing (noisy chest) • Recurrent respiratory infections • Weight loss • Weakness Signs: • • • • • • Hyperinflation Central cyanosis Weight loss Flapping tremors Wheeze Reduced breath sounds Investigations of the COPD: Pulmonary function tests: • ▫ FEV1 <80% • ▫ FEV1 / FVC <70% • ▫ Large lung volumes Severity according to pulmonary function tests • ▫ Mild COPD : FEV1 50-80% • ▫ Moderate : FEV1 30-50% • ▫ Severe : FEV1 < 30% predicted Chest X ray: normal, or hyperinflation, or bullae. Arterial blood gases: • type 1 or 2 respiratory failure. • Type I there is hypoxemia, with low or normal PCO2 • Type II there is hypoxemia and hypercapnea (high PCO2). Full blood count: polycythaemia (high RBCs count as a compensatory mechanism to chronic hypoxemia). Sputum culture to exclude superadded bacterial infection). Treatment • Smoking cessation • Inhaled short and long acting B2 agonists • Inhaled anticholinergics • Theophyllines • Inhaled steroids ( oral in severe cases) • Long term oxygen therapy (LTOT): Oxygen via nasal cannula to maintain PO2 at 60 mmHg • Pulmonary rehabilitation (Aerobic exercises, Upper and lower limbs strengthening,Educational and relaxation sessions). • Lung volume reduction surgeries and bullectomy • Lung transplantation. Causes of death: • Respiratory failure • Heart failure • Cerebrovascular accident