Asthma is a growing health problem, the number of children with asthma has increased markedly, unfortunately, and approximately 75% of children with asthma continue to have chronic problems in adulthood. Asthma is a reversible lung disease that may resolve spontaneously or with treatment, asthma is characterized by obstruction or narrowing of the airways, which are typically inflamed and hyperresponsive to various stimuli. Signs of asthma range from mild wheezing and Dyspnea to life-threatening respiratory failure. Symptoms of bronchial airway obstruction may persist between acute episodes.
Hyper-reactivity leads to airway obstruction due to acute onset of muscle spasm in the smooth muscle of the tracheobronchial tree, thereby leading to a narrowed lumen. In addition to muscle spasm, there is swelling of the mucosa, which leads to edema. Lastly, the mucous glands increase in number, hypertrophy, and secrete thick mucus.
In asthma, the total lung capacity (TLC), functional residual capacity (FRC), and residual volume (RV) increase, but the hallmark of airway obstruction is a reduction in ratio of the forced expiratory volume in 1 second (FEV1) and the FEV1 to the forced vital capacity (FVC).
Although asthma can result from infections (especially viral) and inhaled irritants, it often is the result of an allergic response. An allergen (antigen) is introduced to the body, and sensitizing antibodies such as immunoglobulin E (IgE) are formed. IgE antibodies bind to tissue mast cells and basophils in the mucosa of the bronchioles, lung tissue, and nasopharynx. An antigen-antibody reaction releases primary mediator substances such as histamine and slow-reacting substance of anaphylaxis (SRS-A) and others. These mediators cause contraction of the smooth muscle and tissue edema. In addition, goblet cells secrete a thick mucus into the airways that causes obstruction.
Extrinsic and intrinsic asthma
For many asthmatics, intrinsic and extrinsic asthma coexist. Intrinsic asthma results from all other causes except allergies, such as infections (especially viral), inhaled irritants, and other causes or etiologies. The parasympathetic nervous system becomes stimulated, which increases bronchomotor tone, resulting in bronchoconstriction.
Asthma that results from sensitivity to specific external allergens is referred to as extrinsic (atopic). In those cases where the allergen isn’t obvious, asthma is referred to as intrinsic (nonatopic). Allergens that cause extrinsic asthma include pollen, animal dander, house dust or mold, kapok or feather pillows, food additives containing sulfites, and any other sensitizing substance.
Extrinsic asthma usually begins in childhood and is accompanied by other manifestations of atopy (type I, immunoglobulin [Ig] E–mediated allergy), such as eczema and allergic rhinitis.
With intrinsic asthma, no extrinsic allergen can be identified. Most cases are preceded by a severe respiratory tract infection. Irritants, emotional stress, fatigue, exposure to noxious fumes, and endocrine, temperature, and humidity changes may aggravate intrinsic asthma attacks.
Asthma also called chronic reactive airway disease, chronic inflammatory disorder episodic exacerbations of reversible inflammation and hyperreactivity and variable constriction of bronchial smooth muscle, hypersecretion of mucus, and edema. Asthma that results from sensitivity to specific external allergens is known as extrinsic. In cases in which the allergen isn’t obvious, asthma is referred to as intrinsic.
Extrinsic asthma Allergens include pollen, animal dander, house dust or mold, kapok or feather pillows, food additives containing sulfites, Genetic and environmental: household substances (such as dust mites, pets, cockroaches, mold), pollen, foods, latex, emotional upheaval, air pollution, cold weather, exercise, chemicals, medications, viral infections and any other sensitizing substance.
Extrinsic asthma usually begins in childhood and is accompanied by other manifestations such as eczema and allergic rhinitis. In patients with intrinsic (nonatopic) asthma, no extrinsic allergen can be identified. Most cases are preceded by a severe respiratory tract infection. Irritants, emotional stress, fatigue, and exposure to noxious fumes, as well as endocrine changes and changes in temperature and humidity, may aggravate intrinsic asthma attacks. In many patients with asthma, intrinsic and extrinsic asthma coexist. Exercise may also provoke an asthma attack. In patients with exercise-induced asthma, bronchospasm may follow heat and moisture loss in the upper airways.
Treatment for Asthma
Treatment of acute asthma aims to decrease bronchoconstriction, reduce bronchial airway edema, and increase pulmonary ventilation. After an acute episode, treatment focuses on avoiding or removing precipitating factors, such as environmental allergens or irritants.
Drug therapy is most effective when begun soon after the onset of symptoms. A patient who doesn’t respond to this treatment, whose airways remain obstructed, and who has increasing respiratory difficulty is at risk for status asthmaticus and may require mechanical ventilation.
Nursing Assessment for patients with asthma
An asthma attack may begin dramatically, with simultaneous onset of many severe symptoms, or insidiously, with gradually increasing respiratory distress. It typically includes progressively worsening shortness of breath, cough, wheezing, and chest tightness or some combination of these signs and symptoms.
Patients history, obtain history of allergies thorough description of the response to allergens or other irritants. The patient may describe a sudden onset of symptoms after exposure, with a sense of suffocation. Symptoms include dyspnea, wheezing, and a cough and also chest tightness, restlessness, anxiety, and a prolonged expiratory phase. Ask if the patient has experienced a recent viral infection.
Physical examination. severe shortness of breath can hardly speak, patients use their accessory muscles for breathing. Some patients have an increased anteroposterior thoracic diameter. If the patient has marked, color changes such as pallor or cyanosis or becomes confused, restless, or lethargic, increased risk of respiratory failure.
Percussion of the lungs usually produces hyper-resonance, and palpation may reveal vocal fremitus.
Auscultation high-pitched inspiratory and expiratory wheezes, prolonged expiratory phase of respiration. A rapid heart rate, mild systolic hypertension, and a paradoxic pulse may also be present.
Diagnostic test for asthma
Pulmonary function tests Pulse oximetry. Arterial blood gas (ABG) analysis. Complete blood count. Chest X-rays. Peak Expiratory Flow Rates (PEFR)
Nursing diagnosis for Asthma
Common nursing diagnosis found in Nursing Care Plans for Asthma;
- Impaired gas exchange related to Altered oxygen supply obstruction of airways by secretions, bronchospasm, air-trapping Alveoli destruction Ineffective airway clearance related to obstruction from narrowed lumen and thick mucus imbalanced
- Nutrition: Less than Body Requirements related to Dyspnea, sputum production Medication side effects; anorexia, nausea or vomiting
- Ineffective breathing pattern
- Deficient knowledge (treatment regimen, self-care, and discharge needs)
Sample Nursing care plans for Asthma
ineffective Airway Clearance R/T Bronchospasm
Increased production of secretions, retained secretions, thick, viscous secretions
Decreased energy or fatigue
· Evaluate respiratory rate/depth and breath sounds.
· Assist client to maintain a comfortable position.
· Keep environmental free from sources of allergen such as dust, smoke, and feather pillows to a minimum according to individual situation.
· Encourage/instruct in deep-breathing and directed coughing exercises
· Tachypnea is usually present to some degree and may be pronounced during respiratory stress.
· facilitates respiratory function using gravity; however, client in severe distress will seek the position that most eases breathing
· Precipitators of allergic type of respiratory reactions that can trigger or exacerbate onset of acute episode.
· To maximize cough effort, lung expansion and drainage, and reduce pain impairment.
· Respiratory Status: Airway Patency
· Maintain patent airway with breath sounds clear or clearing.
· Demonstrate behaviors to improve or maintain clear airway.
impaired Gas Exchange R/T Altered oxygen supply, obstruction of airways by secretions, bronchospasm
· monitor skin and mucous membrane color.
· Monitor vital signs
· Encourage adequate rest and limit activities to within client tolerance.
· Monitor and graph serial ABGs and pulse oximetry.
· Administer medications as indicated
· Duskiness and central cyanosis indicate advanced hypoxemia
· Increased PaCO2 signals impending respiratory failure for asthmatics.
· Demonstrate improved ventilation
· Demonstrate adequate oxygenation of tissues by ABGs within client’s normal limits
· absence of symptoms of respiratory distress
Patient Teaching Discharge and Home Healthcare Guidelines for Asthma
To prevent asthma attacks, teach patients the triggers that can precipitate an attack. Teach the patient and family the correct use of medications, including the dosage, route, action, and side Effects. In rare instances, asthma can lead to respiratory failure (status asthmaticus) if patients are not treated immediately or are unresponsive to treatment. Explain that any Dyspnea unrelieved by medications, and accompanied by wheezing and accessory muscle use, needs prompt attention from a healthcare provider.
- Teach the patient and his family to avoid known allergens and irritants.
- Teach the patient about his medications, drug interactions, including proper dosages, administration instructions, and adverse effects.
- Teach the patient how to use a metered dose inhaler.
- Explain how to use a peak flow meter to measure the degree of airway obstruction, If the patient has moderate to severe asthma. Tell him to keep a record and Explain the importance of calling the physician at once if the peak flow drops suddenly
- If the patient develops a fever above 100° F (37.8° C), chest pain, shortness of breath without coughing or exercising, or uncontrollable coughing. Tell the patient to notify the physician
- Teach the patient and his family an uncontrollable asthma attack requires immediate attention.
- Teach the patient diaphragmatic and effective coughing techniques.
- Urge him to Increase fluid intake to help loosen secretions and maintain hydration.
- Teach the patient and his family important of Regular medical follow-up care, when to notify healthcare professional of changes in condition, and periodic spirometry testing, chest x-rays, and sputum cultures.