BRONCHIAL ASTHMA Islamic University Nursing College

Definition Asthma is a chronic inflammatory disease of the airways which develops under the allergens influence, associates with bronchial hyperresponsiveness and reversible obstruction and manifests with attacks of dyspnea, breathlessness, cough, wheezing, chest tightness and sibilant rales more expressed at breathing-out.

Epidemiology According to epidemiological studies asthma affects 1- 18% of population of different countries. Only in 2006 more than 300 million patients suffered from asthma all over the world, 250 thousands of patients die of asthma. The incidence of asthma is higher in countries with increased air pollution.

causes Allergic reactions to plants, foreign bodies in the air way.

Etiology The allergens are divided into: Communal, Industrial, Occupational, Natural Pharmacological

Сommunal allergens are contained in the air of apartment houses. They are: House-dust mites which live in carpets سجادة, mattresses and upholstered الاثاث المنجدfurniture; Vital products of domestic insects (e.g., cockroachالصرصور); Tobacco smoke during active or passive smoking; Various communal aerosols and synthetic detergents.

Among the industrial allergens nitric, carbonic, sulfuric oxides, formaldehyde, ozone and emissions of biotechnological industry - main components of industrial and photochemical. The most important occupational allergens are dust of stock buildings, mills مطاحن, weaving-mills, book depositories etc. Natural allergens are represented by plant pollen (especially ambrosia عطور, wormwood and goose-foot pollen) and different respiratory, particularly viral, infections.

Some allergens which may cause asthma House-dust mites which live in carpets, mattresses and upholstered furniture Spittle, excrements, hair and fur of domestic animals Plant pollen Pharmacological agents (enzymes, antibiotics, vaccines, serums) Food components (stabilizers, genetically modified products) Dust of book depo- sitories

Asthma Triggers ©2010

Trigger-factors, which provoke bronchospasm, are: a simultaneous penetration of a large quantity of allergen, viral respiratory infection, hyperventilation, physical exertion, emotional stress, becoming too cold, adverse weather conditions, administration of some medicines (aspirin,  -blockers).

Pathophysiology Asthma pathophysiology is quite difficult and insufficiently studied. Undoubtedly, in most cases the disease is based on 1 type hypersensitivity reaction. The genesis of any allergic reaction may be divided into immune, pathochemical and pathophysio- logic phases.

Classifications of Asthma 1. Spasmodic: sporadic in nature with varying intervals of free and difficulty due to precipitating factors often readily defined. 2. Continuous: some shortness of breath on occasion, transit wheezing on strenuous exercise and wheezy rales hard deep inspiration.

Classifications of Asthma cont… 3. Intractable: persistent wheezing requiring regular daily medication for either control of symptoms or ability to function. 4. Status Asthmaticus: sever attach in which patient deteriorates in spite of adequate treatment.

Clinical manifestations Classic signs and symptoms of asthma are: Attacks of expiratory dyspnea Shortness of breath Cough. Chest tightness Wheezing (high-pitched whistling sounds when breathing out) Sibilant rales

In typical cases in development of asthma exacerbation there are 3 periods – prodromal period, the height period and the period of reverse changes. At the prodromal period: vasomotoric nasal reaction with profuse watery discharge, sneezing, dryness in nasopharynx, paroxysmal cough with viscous sputum, emotional lability, excessive sweating, skin itch and other symptoms may occur.

At the peack of exacerbation there are: expiratory dyspnea forced position with supporting on arms poorly productive cough cyanotic skin and mucous tunics hyperexpansion of thorax with use of all accessory muscles during breathing at lung percussion: tympanitis, shifted downward lung borders at auscultation: diminished breath sounds, sibilant rales, prolonged breathing-out, tachycardia. in severe exacerbations: the signs of right-sided heart failure (swollen neck veins, hepatomegalia), overload of right heart chambers on ECG.

At the period of the reverse changes, Which comes spontaneously or under pharmacologic therapy. Dyspnea and breathlessness relieve or disappear. Sputum becomes not so viscous. Cough turns to be productive. Patient breathes easier.

Asthmatic status The severe and prolonged asthma exacerbation with intensive progressive respiratory failure, hypoxemia, hypercapnia, respiratory acidosis, increased blood viscosity and the most important sign is blockade of bronchial  2-receptors. Stages: 1 st - refractory response to  2-agonists ( relaxation of the smooth muscles ) 2 nd - “silent” lung because of severe bronchial obstruction and collapse of small and intermediate bronchi; 3 rd stage – the hypercapnic coma.

In many cases asthma, particularly intermittent, manifests with few and atypical signs: episodic appearance of wheezing; cough, heavy breathing occurring at night; cough, hoarseness after physical activity; “seasonal” cough, wheezing, chest tightness the same symptoms occurring during contact with allergens, irritants; lingering course of acute respiratory infections.

Diagnosis Typical clinical manifestations and lung function assessment are sufficient for diagnosis of asthma.

Management 1. Avoiding the contact with allergen. If it is impossible, the specific hyposensitization with standard allergens should be performed. It is rather effective in case of monoallergy, in intermittent and mild persistent asthma, in remission phase. 2. Elimination of trigger factors (rational job placement, changing the residence, psychological and physical adaptation, careful drug using) is the second condition for successful asthma treatment. 3. Optimally selected medical care is the base of asthma management.

Combined inhaled drugs (corticosteroids with  2- agonists) (nebulasers, turbuhalers, spasers, spinhalers, sinchroners) enhance the effectiveness of asthma therapy.

Management of asthmatic status Oxygen Systemic corticosteroids (Hydrocortisone 200mg or Prednisolone 50 mg/day per) Inhalations of short-acting  2-agonists - Salbutamol 5mg or Fenoterol 2mg through nebulaser – 3 times at 1 st hour, then once an hour till distinct improvement of patient’s condition is achieved; then 3-4 times a day. Inhaled anticholinergic drugs or Aminophylline IV. If ineffective - artificial lung ventilation.

Prognosis In case of early detection and adequate treatment the prognosis for the disease is favourable. It becomes serious in severe persistent and poorly controlled (insensitive for corticosteroids) asthma.

The examination of working capacity The patients with unfavorable for the disease conditions of work need the job replacement. Physical labours with severe asthma are disable to work.

Prophylaxis Preservation of the environment, healthy life-style (smoking cessation, physical training) – are the basis of primary asthma prophylaxis. These measures in combination with adequate drug therapy are effective for secondary prophylaxis.