17. Asthma

OTHER NAMES
allergic asthma; intrinsic asthma; asthma; exercise induced asthma; status asthmaticus
DEFINITION
Bronchial asthma is a lung disorder characterized by periodic attacks of wheezing altemating with periods of relatively normal breathing.
CAUSES, INCIDENCE, AND RISK FACTORS
Bronchial asthma is usually intrinsic (no cause can be demonstrated), but is occasionally caused by a specific allergy (such as allergy to mold, dander, dust). Although most individuals with asthma will have some positive allergy tests, the allergy is not necessarily the cause of the asthma symptoms.
Symptoms can occur spontaneously or can be triggered by respiratory infections, exercise, cold air, tobacco smoke or other pollutants, stress or anxiety, or by food allergies or grug allergies. The muscles of the bronchial tree become tight and the lining of the air passages become swollen, reducing airflow and producing the wheezing sound. Mucus production is increased.
Typically, the individual usually breathes relatively normally, and will have periodic attacks of wheezing. Asthma attacks can last minutes to days, and can become dangerous if the airflow becomes severely restricted. Asthma affects 1 in 20 of the overall population, but the incidence is 1 in 10 in children. Asthma can develop at any age, but some children seem to outgrow the illness. Risk factors include self or family history of eczema, allergies or family history of asthma.
PREVENTION
Decrease or control exposure to known allergens by staying away from cigarette smoke, removing animals from bedrooms or entire houses, and avoiding foods that cause symptoms. Allergy desensitization is rarely successful in reducing symptoms.
SYMPTOMS
- wheezing
- usually begins suddenly
- composed of a sequence of attacks (episodic)
- may be worse at night or in early morning
- aggravated by exposure to cold air
- aggravated by exercise
- resolves spontaneously
- good relief from bronchodilators (drugs that open the airways)
- rales
- cough with sputum (phlegm) production containing mucus (mucoid sputum)
- cough increasing recently
- shortness of breath aggravated by exercise
- shortness of breath occurs only when wheezing
- breathing requires increased work
- intercostal retractions
Emergency symptoms:
- extreme difficulty breathing
- bluish color to the lips and face
- severe anxiety
- rapid pulse
- sweating
Additional symptoms that may be associated with this disease:
- nasal flaring
- coughing up blood
- chest pain
- breathing, absent temporarily
- a feeling of chest tightness

•increased front-to-back diameter of the chest (barrel shaped chest)
- abnormal breathing pattem, exhalation takes more than twice as long as inspiration
SIGNS AND TESTS
Listening to the chest (anscultation) reveals wheezing during an episode. However, lung sounds are usually normal between episodes.
Tests may include:
- pulmonary function tests
- chest X-ray
- CBC shows increase in eosinophils
- arterial blood gas
This disease may also alter the results of the following tests:
- Immnnoelectrophoresis - serum
- eosinophil count - absolute
-CPK
Treatment Options

Treatment Strategy

 _... Controlling environmental stimuli or triggers _... Anti-inflammatory drugs to promote relaxation of the bronchial smooth muscle _... Bronchodilator drugs to stimulate the beta2-adrenergic agonist receptors during an attack _... Antibiotics, when precipitated by bacterial infection _... Combination of these treatments for severe attacks, in addition to oxygen and injected epinephrine in emergencies

Drug Therapies

 _... Nonsteroidal anti-inflammatory inhalers, such as cromolyn sodium (Intal); prevents mediator release from airway mast cells; dose dependent on severity; may cause coughing _... Corticosteroids, such as methylprednisolone (60 to 80 mg intravenous push each six to eight hours for 36 to 48 hours), for severe attacks; prevents migration and activation of inflammatory cells _... Corticosteroid inhalers, such as beclomethasone dipropionate (Beclovent, Vanceril, or Asthmacort), 1 to 5 puffs two to four times a day; side effects include: cough, hoarseness, oral candidiasis (thrush); chronic adverse side effects rare Bronchodilators: _... Beta2-adrenergic agonists, such as albuterol (more than 8 puffs three to four times a week warrants reassessment), administer by metered dose inhalers (MDI) or by nebulizer in the hospital (every one to two hours); stimulate adrenaline or epinephrine receptors; side effects include: rapid or irregular heartbeat, insomnia, shakiness, nervousness _... Anticholinergic agents, such as ipratropium bromide (Atrovent), inhibit the parasympathetic nervous system; by inhaler (dose varies); side effects include: dry mouth, cough, headaches, urinary retention, worsening of glaucoma _... Methylxanthines, such as aminophylline and theophylline, are now used only intravenously for severe attacks and for nighttime asthma because of side effects, which include: nausea, vomiting, headaches, insomnia, tremor, seizures, abnormal heart rhythms, death

Complementary and Alternative Therapies

 Discerning and eliminating triggers are key in treating asthma. Suspect food allergy if asthma develops in childhood, if there is a positive family history, if atopic dermatitis is present, or with poorly controlled asthma with elevated total serum IgE levels. Following nutritional guidelines and using herbal support as needed may be effective in reducing inflammation and hypersensitivity reactions. Hypersensitivity reactions may be associated with stress and anxiety. Mind-body techniques such as diaphragmatic breathing, meditation, tai chi, yoga, and stress management may help reduce frequency, duration, and severity of symptoms.

Nutrition

 Note: Lower doses are for children. _... Eliminate all food allergens from the diet. The most common allergenic foods are dairy, soy, citrus, peanuts, wheat, fish, eggs, corn, food colorings, and additives. An elimination/challenge trial may be helpful in uncovering sensitivities, or an IgG ELISA food allergy test may be used. Remove suspected allergens from the diet for at least two weeks. Re-introduce foods at the rate of one food every three days. Watch for reactions which may include gastrointestinal upset, mood changes, headaches, and exacerbation of asthma. Warning: Do not challenge peanuts, or any other food, if there is history of anaphylaxis. _... Reduce pro-inflammatory foods in the diet including saturated fats (meats, especially poultry, and dairy), refined foods, and sugar. Patients sensitive to antibiotics should eat only organic meats to avoid antibiotic residues. _... Increase intake of fresh vegetables, whole grains, legumes, onions, and garlic if not sensitive to those foods. _... Vitamin C (250 to 1,000 mg bid to qid) inhibits histamine release and increases prostacyclin production which promotes vasodilation. Vitamin C from rose hips or palmitate is citrus-free and hypoallergenic. Vitamin C taken one hour before exposure to allergen may reduce reactions. This also applies to exercise-induced asthma. _... B6 (50 to 200 mg/day) may improve symptoms, particularly in children with a defect in tryptophan metabolism. Use caution with high dose (usually above 500 mg per day in adults). If neuropathy develops, discontinue immediately. Pyridoxal-5-phosphate (P5P) is an activated form of B6 that may be more readily bio-utilized. _... Magnesium (200 mg bid to tid) relaxes bronchioles. Magnesium may cause loose stools in sensitive patients. _... Consider hydrochloric acid supplementation as deficiency is believed to increase the number and severity of food sensitivities and impair micronutrient absorption. _... B12 is linked to hypochlorhydria and a deficiency may increase reactivity to sulfites. Dr. Jonathan Wright's protocol for childhood asthma: Hydroxycobalamin 1 cc (1,000 mcg) IM every day for 30 days, then three times weekly for two weeks, two times weekly for two weeks, then once weekly (according to response). Oral B12, 1 mg per day, has also been shown to be helpful. _... N-acetylcysteine (50 to 200 mg tid) and selenium (50 to 200 mcg/day) increase glutathione peroxidase activity and protect lung tissue from oxidative damage.

EXPECTATIONS (PROGNOSIS)
Asthma is a disease that has no cure. With proper self management and medical treatment, most people with asthma can lead normal lives.
COMPLICATIONS
- respiratory fatigue
- pnenmothorax
- complications from overuse of medications (particularly inhalers) 

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Compiled and Shared By: Habib Anwar 

habib.anwar@hotmail.com