What are its Symptoms?
An asthma attack may begin dramatically, with the person experiencing many severe symptoms at once. But sometimes it begins slowly, causing gradually increasing respiratory distress. Typically, the person becomes increasingly short of breath, with worsening cough, wheezing, and chest tightness or some combination of these symptoms.
During an acute attack, the cough sounds tight and dry. fu the attack subsides, thick, sticky sputum is produced (except in young children). The lungs overinflate, causing use of accessory breathing muscles, particularly in children. An increased pulse, abnormally fast breathing, and profuse sweating are also common. In severe attacks. the person may be unable to speak more than a few words without pausing for breath. A bluish skin discoloration, confusion, and sluggishness signal the start of respiratory failure.
How is it Diagnosed?
In people with asthma, lab tests often show these abnormalities:
• Pulmonary fUnction studies reveal signs of airway obstruction. (However, between attacks, these studies may be normal.)
• Pulse oximetry may reveal decreased arterial oxygen saturation.
• Arterial blood gas analysis provides the best indication of an attack's severity. In acutely severe asthma, the partial pressure of arterial oxygen measures less than 60 millimeters of mercury, the partial pressure of arterial carbon dioxide is 40 millimeters of mercury or more, and pH usually decreases.
• Complete blood count with white blood cell differential reveals an increased eosinophil count .
• Chest X-rays may show overinflated lungs with areas of collapsed air sacs.
Before ordering tests for asthma, the doctor rules out other causes of airway obstruction and wheezing. In children, such causes include cystic fibrosis, chest rumors, and acute viral bronchitis. In adults, other causes include obstructive pulmonary disease, heart failure, and epiglottitis.
How is it Treated?
Treatment of acute asthma aims to ease bronchoconstriction, reduce bronchial airway swelling, and improve pulmonary ventilation. After an acute episode, treatment includes avoiding or removing factors that trigger asthma, such as environmental allergens or irritants.
If the person knows which substances trigger the asthma, he or she may receive limited amounts of the offending substance in a series of injections. This desensitizing therapy curbs the person's immune response to the substance. If asthma is caused by an infection, the doctor prescribes antibiotics.
Drug therapy for asthma is most effective when started soon after signs and symptoms begin. It usually includes:
• bronchodilators that open blocked airways; commonly used bronchodilators include methylxanthines (Theo-Dur and Aminophyllin) and beta-2 adrenergic agonists (Ventoline and Brethaire)
• corticosteroids (Solu-cortef, Orasone, Medrol, and Beconase) to reduce inflammation and suppress the immune response, thereby easing airway inflammation and swelling
• Nasalcrom and Tilade to help block the release of the chemical mediators active in asthma
• anticholinergic bronchodilators, such as Atrovent, which block acetylcholine, another chemical mediator of asthma attacks.
For the most part, medical treatment of asthma is tailored to each person. However, the following treatments are generally used:
• Chronic mild asthma. A betaradrenergic agonist by metered-dose inhaler is used (alone or with Nasalcrom) before exercise and exposure to an allergen to prevent symptoms. The person uses the drug every 3 to 4 hours if symptoms occur.
• Chronic moderate asthma. At first, the person receives an inhaled beta-adrenergic bronchodilator, an inhaled corticosteroid, and Nasalcrom. If symptoms persist, the doctor may increase the inhaled corticosteroid dosage and add sustained-release Theo-Dur or an oral betaradrenergic agonist (or both). Brief therapy with oral corticosteroids also may be used.
• Chronic severe asthma. Initially, the person may need around-theclock oral bronchodilators with a long-acting theophylline or a beta-2 adrenergic agonist. This therapy is supplemented with an inhaled betaradrenergic agonist and an inhaled corticosteroid with or without Nasalcrom. In acute attacks, the doctor may add an oral corticosteroid.
• Acute asthma attack. Acute attacks that don't respond to self-treatment may require hospital care, inhaled or injected beta-2 adrenergic agonists and, possibly, oxygen. The doctor may prescribe intravenous therapy. People who don't respond to this treatment, whose airways remain blocked, and who have increasing breathing difficulty are at risk for a potentially lethal condition called status asthmaticus. To maintain their breathing, they may require mechanical ventilation.
• Status asthmaticus. A person with status asthmaticus (an acute, severe, prolonged asthma attack) needs aggressive drug therapy. He or she receives a beta-2 adrenergic agonist by nebulizer every 30 to 60 minutes. The doctor may also give an Adrenalin injection; intravenous corticosteroids, aminophylline, and fluids; and oxygen. Some people need mechanical ventilation to assist breathing.
What can a person with Asthma do?
• Avoid known allergens and irritants.
• If you have trouble using a metered-dose inhaler, you may need an extender device to improve drug delivery and lower the risk of yeast infection with orally inhaled corticosteroids.
• If you have moderate to severe asthma, learn how to use a peak Howmeter to measure the degree of airway obstruction. Keep a record of peak How readings and bring it to medical appointments. Call the doctor at once if the peak How drops suddenly. (A drop may signal severe respiratory problems.)
• Notify the doctor if you develop a fever above 100° F (37.8° C), chest pain, shortness of breath without coughing or exercising, or uncontrollable coughing. An uncontrollable asthma attack requires immediate attention.
• To manage asthma attacks, learn diaphragmatic and pursed-lip breathing as well as effective coughing techniques.
•Drink at least 6 eight-ounce glasses of fluids daily to help loosen airway secretions and maintain hydration