BRONCHIA ASTHMA: BRONCHIA ASTHMA Presented By: Roshina Saeed Pham-D Bronchial Asthma: Bronchial Asthma Definition: Characterized by episodes of dyspnea accompanied by wheezing resulting from temporary narrowing of the bronchi by muscular spasm and mucus secretion. History : History Magendie (1782-1855), a French physiologist observed (1839) that, A dog which tolerated quite well first two injections of albumin on two consecutive days. But on 3 rd day it died immediately giving injection. He concluded injection of albumin into the blood of animal may have fatal consequences. Slide 5:
Later landuis and hayem(1885-1890) reported that repeated injection of protein causes the hypersensitiveness of laboratory animal's. Richet named it anaphylaxis. But this term was not acceptable to all those working
.Pirquet proposed the term allergy.
Facts About 17 million Americans have asthma. Most common chronic childhood disease, effecting about 500 children's. 14 people die each day from asthma. (EPA indoor
division, Jan 2001)
Types: Types Early on set asthma (episodic, atopic or extrinsic asthma). Occurs in childhood and in atopic indvidual.Atopy runs in families. Late onset asthma (chronic or non atopic or intrinsic asthma). This occurs mostly in adults. External allergens play no part in the production of his type of asthma, so the term intrinsic asthma is sometime used. Pathophysiology: Pathophysiology The asthmatic inflammatory has been characterized as consisting of an immediate response and a late response. 1. Immediate response: Initiates immediate response in the form of dyspnoea, cough ,chest tightness and wheezing. Response occurs shortly after allergen exposure within the first 15 min – 1 hour. Mast cells are activated leading to release of chemical mediators, produce inflammatory reaction and symptom formation. Slide 9: Late phase response ( or reaction): This inflammatory phase occurs 4-6 hours later after exposure to allergens. It is thought to be caused by an influx of inflammatory cells such as eosinophils and neutorphils. That cause airway injury.
Presentations of bronchial asthma Episodic Asthma Chronic Asthma Severe Acute Asthma (status asthmatics)
Episodic Asthma : Episodic Asthma Occurs in atopic individuals. No respiratory symptoms between episodes of asthma. Wheeze and dyspnoea occur at bed time. Factors include allergens, exercise and viral infection like common cold. Chronic Asthma: Chronic Asthma Symptoms may be chronic unless treated. Include chest tightness, wheeze, dyspnoea, spontaneous productive cough. Severe Acute Asthma (status asthmatics) :
cont... Severe Acute Asthma (status asthmatics)
threatening attacks of asthma. State of continuous or prolonged attack of asthma associated with severe respiratory distress & arterial hypoxemia. Acute and chronic both types may lead to status asthmatics. Patient is unable to speak because of severe dyspnea.
Slide 15: If the wheezing is decreased or absent “ silent chest”. Confusion is secondary to hypoxia. Investigation: Investigation Chest X-ray: During attack lungs appear hyper inflated while between episodes chest x-ray is usually normal. Peak Expiratory Flow Rate (PEFR): Peak flow meter can indicate the severity of airflow limitation. 450-650 L/min in men 350-200 L/min in women
Management Prevention: Drugs Treatment of Asthma: Long term control medications Corticosteroids Most potent Reduce both acute and chronic inflammation
Slide 18: Inhaled corticosteroids Becotide inhaler is a low dose inhaled corticosteroid contains 50mcg betamethasone per dose and is given as 2 puffs 2-4 times daily. Becloforte inhaler is a high dose corticosteroid and contains 250 mcg betamethasone per dose and is given as 2 puffs 2-4 times daily. Side Effect: Oran candidacies. Slide 19: cont... High- dose corticosteroids more than 800mcg/day may lead to systemic effects such as osteoporosis, skin thinning and cataract. Oral Corticosteroids: Dose should be low. Alternate-day treatment is preferred. Prednisolone (Tab. Deltacortil 5mg) 30-60 mg/day as a single dose given orally in the morning. Withdraw treatment is necessary when used for more than 3 weeks. Slide 20: Long – Acting Bronchodilators Beta-adrenergic agonists. Provide bronchodilation for up to12 hours after a single dose. Onset of action is delayed so not used in acute asthma. Salmeterol inhaler. Phosphodiestrase inhibitors Sustained release theophylline preparation (Theograd 350 mg) is used as adjuvant therapy to control nocturnal symptoms. Dose 200-500mg BID. Slide 21: Mediator inhibitors: Cromolyn Sodium (mast cell stabilizer). Dose 2 puffs 4 times daily 10-15 minutes before exercise. Cromolyn has no side effects. Monteleukast (Tab. Singulair 5mg & 10mg once a day at bedtime). Quick relief medications: Inhaled beta-adrenergic agonists. Salbutamol and terbutaline are the first line therapy for rapid symptomatic improvement inpatients with acute bronchospasm. Dose: salbuamol 2 puffs as required. Slide 22: Oral Beta-Adrenergic Agonists: Salbutamol is available in 2mg, 4mg, and given 3-4 times daily, 4mg SR (sustained Release), 8mg SR are given 3 times daily. Systemic Corticosteroids: Prednisolone (Tab. Deltacortil 5mg) is given as 0.5-1 mg/kg/d in one or two divided doses orally for 3-10 days. Hydrocortisone (inj. Solu - Cortef 100mg, 250mg 500mg) is given as 2.5-4 mg//kg i.v 6 - hourly in severe acute asthma (status asthmaticus). Slide 23: Anticholinergic: Ipratropium bromide (atem inhaler & Atrovent nebulizer solution) is useful in the following conditions: Patients not responding to beta agonists Patients whose bronchospasm is secondary to bronchitis or due to beta-blocker medications Slide 24: Stepwise Management Of Chronic Persistent Asthma: step 1: Occasional use of inhaled short-acting b2-adrenoceptor agonists. step 2: Low-dose inhaled steroids (or other anti-inflammatory agents. step 3 : High-dose inhaled steriods or low-dose inhaled steroids plus long-acting inhaled B2-adrenoceptor agonist. step 4: High –dose inhaled steroids and regular bronchodilators. step5: Addition of regular oral steroid therapy. Management Of Acute Status Asthmatics:: Management Of Acute Status Asthmatics: Oxygen: High concentration of oxygen (40-60%) is used at a high flow rate to treat hypoxemia Generally started at 2- 4 lit/min via nasal canulla or ventimask Monitoring with pulse oximeter is necessary Oxygen saturation above 90% Slide 26: Inhaledbeta-2 Agonist: Salbutamol 2.5-5mg (.5-1ml) diluted in 3ml of normal saline mixed with oxygen should be given by nebulizer over 60-90 minutes. Systemic corticosteroids: Systemic steroids are also used for acute asthma. Slide 27: Antibiotics: The routine use of antibiotic therapy for acute or chronic asthma is not recommended.If there is fever, purulent sputum, leukocytosis on X-ray chest suggesting antibiotic Injection Augmantin 1.2 g i.v 8 hourly.