What is Asthma?

Asthma is a serious lung disease that causes reversible narrowing of the bronchial tubes that carry air into the lungs. This causes problems getting air into and out of the lungs.

The bronchial airways of asthmatics react to things like smoke, dust, molds, pollen, dander and many other things which do not affect persons without asthma.

During early stages of an asthma attack stimulation of cells within bronchial airways trigger release of substances (e.g., histamine, tryptase, leukotrienes and prostaglandins) called inflammatory mediators. These mediators cause smooth muscle within the walls of the bronchial airways to contract, resulting in narrowing of the airways.

Inflammatory mediators also cause certain cells (eosinophils and neutrophils) to become activated and migrate to the bronchial airways where they cause injury. This "late phase asthmatic response" causes inflammation of surrounding bronchial tissues and excessive secretion of mucous into the bronchial airways. This causes even further narrowing of the airways. Unlike early phase asthma, late phase airway swelling is not quickly reversible.

It is very important to understand that asthma is a chronic disease for many affected persons due to persistent inflammation and swelling in the bronchial tubes, even when a person does not seem to have asthma symptoms.

Facts about Asthma

If you have asthma, you are not alone. More than 17 million people in the United States have this lung disease. Of these, almost 5 million are children. 1

Asthma is responsible for more than 14 million visits a year to a health care professional, almost a half-million hospitalizations, 1 million emergency room visits, and more than 5,000 deaths annually in the United States.

Proper asthma care could prevent a vast majority of these problems. But you do not have to put up with the problems asthma can cause. Your Asthma Can Be Controlled With Proper Care With your doctos help, you can control your asthma and become free of symptoms.

What causes Asthma?

The cause of asthma is not known. Many different factors play a role in the development of asthma in different individuals with the end result being the reversible narrowing of bronchial airways. 2 Asthma triggers include:

• Immunologic factors
• Viral respiratory infections (particularly in children under 2)
• Sinus infections
• Allergies (most important trigger in children over 2 years of age)
• Exercise- induced asthma (EIA)
• Irritants such as cigarette smoke, burning wood, and air pollution
• Gastroesophageal reflux disease
• Medications
• Food additives and sulfites
• Weather
• Psychologic stressors
• Occupational asthma

Who gets Asthma?

Asthma is a problem among all races. But the asthma death rate and hospitalization rate for blacks are three times the rate of whites. Although asthma is more common in children and young adults it can occur at any age. Asthma occurring in children over 2 years of age has identifiable allergic triggers 90% of the time. Asthma occurring for the first time in adults often has less identifiable triggers and tends to be more resistant to treatment.

What are symptoms of Asthma?

Asthma symptoms can range from very mild to severe, depending on both the individual and the particular situation.

Common Symptoms of Asthma include:

• Coughing
• Wheezing (a whistling noise when you breathe)
• Chest tightness (the feeling that someone is squeezing or sitting on your chest)
• Shortness of breath

You may have all of these symptoms, some of them, or just one. Symptoms can be mild or severe. 3

Asthma should be considered in persons with persistent cough (particularly if the cough is worse at night) or if the symptoms worsen with exercise, viral illness, weather changes or exposures to airborne chemicals, dust, tobacco smoke or other allergens, such as animal dander, cockroaches, house dust mites, mold and pollens.

How is Asthma treated and prevented?

Successful treatment and prevention of asthma involves being thoroughly educated about asthma, working closely with your doctor, recognizing and avoiding known triggers, and proper use of medications.

Know how well your lungs are working

Two tests of how well your lungs work are spirometry and peak expiratory flow (PEF) measurements.

Spirometry measures how much air you blow out in one second- This number is know as the forced expiratory volume (FEV 1). Spirometry requires a sophisticated device that is usually only available in a physician's office or hospital. Spirometry devices can also calculate other values that help distinguish asthma from other breathing problems.

Spirometry is recommended:

• At initial assessment/diagnosis of asthma
• After treatment started and PEF has stabilized
• Every 1 to 2 years

Peak flow (PEF) measures the maximum speed you blow out air. These results are not as accurate but are simple to perform. A peak flow meter can be used any place and is very inexpensive. Peak flow meters are for monitoring of already diagnosed asthma, not diagnosis.

PEF monitoring:

• All patients except those with MILD-INTERMITTENT asthma should:

1. Learn to monitor their PEF and have a peak flow meter at home
2. Monitor during asthma flare-ups
3. Perform daily monitoring for better control (MODERATE or SEVERE)

All asthma patients should know their expected best peak flow and use it to compare future peak flow measurements. Symptoms of asthma are often not noticeable until PEF has dropped below 80% of predicted best measurement.

Know how to correctly use your medications

Asthma medications generally come in inhaled or oral forms. Most treatment consists of using inhaled medications. Medications are most effective and have the least effects on other parts of the body when inhaled directly into the lungs. Medications can be inhaled using :

Metered dose inhaler (MDI)

An MDI (or puffer) is a small canister containing asthma medication that delivers the same amount of medication each time you spray it in your mouth. MDI's are reliable and can be carried anyplace. They may be hard for young children and those with coordination impairments to use.

Medication nebulizer

A nebulizer is a small machine turns liquid (nebulizable) forms of asthma medication into fine mist that you inhale. Anyone can use nebulizers and the amount of medication used can be adjusted. Nebulizers need a power source, require more maintenance and are not needed by most asthmatics.

The best treatment is prevention of asthma attacks- This means keeping on top of your asthma when you are feeling well and always being prepared in case of emergency!

Asthma Medications

Asthma medications work in one of two basic ways:

• Bronchodilators relax the tightening of muscles that narrow the bronchial airways: They have little or no effect on the inflammatory (swelling) part of an asthma attack.  Bronchodilators are typically used to give quick relief when a person starts to develop symptoms of an asthma attack.
  
  
• Inflammatory mediators are medications that either help prevent or treat the inflammatory phase of asthma: These medications have much less effect on treating spasm of bronchial muscles. Anti-inflammatory medications are used on a regular basis ( except in persons with very mild or infrequent asthma attacks) for long term control to prevent recurrent asthma attacks.

It is important to remember that many asthmatics will need to take at least two different types of medications.

Bronchodilators
Beta agonists	• Relax bronchial smooth muscle • Most effective when inhaled • May also increase heart rate and cause muscle tremor (much less so with newer beta agonists). Safe to use Both short and long acting beta agonists available. Only short acting medications should be used to treat worsening asthma symptoms. Long acting beta agonists should not be used as a single agent for long-term control but instead should be used in combination with inhaled corticosteroids or other anti-inflammatory agents. Salmeterol is useful in the management of nocturnal and exercise-induced asthma.
Anticholinergics	•Relax bronchial smooth muscle by different mechanism than beta agonists • Most effective when inhaled • May have additive benefits when used in combination with beta agonist. Ipratropium (atrovent) safe to use with relatively few side effects.  Atropine (not commonly used for asthma) may produce increased heart rate, restlessness, thirst, blurry vision, trouble urinating, or increased eye pressure.
Theophylline	• Is a central nervous system stimulant as well as bronchodilator • Older medication taken orally. • Not as commonly used because less effective and more side effects than beta agonists and anticholinergics. • Blood levels must be checked over time. Theophylline still used in mild asthma, in sustained release form for control of night symptoms and in some elderly persons with combination of asthma and emphysema.
Anti-inflammatory Medications
Corticosteroids	• Most potent medications available to decrease swelling of the bronchial airways. • Not the same thing as muscle building steroids. • May be inhaled or taken orally. • Inhaled steroids are used to prevent symptoms and control mild, moderate, and severe asthma. Inhaled steroids are safe when taken at recommended doses. This is because the medicine goes right to your lungs where you need it. This reduces the amount of medicine you need and the chance of any side effects. • Reduced growth rate may occur in children on long term systemic (oral or injected) corticosteroids. Growth suppression has not been clearly shown with inhaled medications. • Steroid tablets or liquids are used safely for short times to quickly bring asthma under control. They are also used longer term to control the most severe asthma.
Mast-Cell Stabilizers	• Help prevent both early and late phase bronchoconstriction by preventing the release of inflammatory mediators from sensitized mast cells in bronchial tissues. Not a true anti-inflammatory medication. • Extremely safe with no serious side effects and no known interactions with other medications. • Medications of choice in children for long term control of asthma but less effective than corticosteroids. • Quite effective for allergic type asthma. • May leave bad taste in mouth
Leukotriene Modifiers	• Medications in this group either block or inhibit the formation of leukotrienes (molecules made by a number of different cells that cause inflammation). • Have anti-inflammatory effect. • Work sooner than inhaled steroids • Can be given by mouth once or twice daily • Relatively safe although inflammation of liver can occur in rare cases. • Not as effective as inhaled corticosteroids • May decrease the amount of corticosteroids required • No agent approved for use in children under 6 years
Asthma Long-Term-Control Medications- Generic name | Brand name
Steroids:
Inhaled beclomethasone Double Strength budesonide flunisolide fluticasone triamcinolone	Beclovent ¨ Vanceril ¨ , Vanceril ¨ Pulmicort Turbuhaler ¨ AeroBid ¨ , AeroBid-M ¨ Flovent ¨ Azmacort ¨
Mast Cell Stabilizers
Inhaled cromolyn sodium Inhaled nedocromil sodium	Intal ¨ Tilade ¨
• Nedocromil appears to be more effective than cromolyn in inhibiting bronchospasm induced by exercise, cold air and provocative testing.
Leukotriene Modifiers [Tablets]
zafirlukast zileuton montelukast	Accolate ¨ Zyflo ¨ Singulair
Long-Acting Beta 2 -Agonists
levalbuterol HCl salmeterol (inhaled) albuterol (tablets)	Xopenex (Inhalation Solution) Serevent ¨ Volmax ¨, Proventil Repetabs ¨ (extended release)
Theophylline: Tablets or liquid
Aerolate ¨ III Aerolate ¨ JR Aerolate ¨ SR Choledyl ¨ SA Elixophyllin ¨ Quibron ¨ -T Quibron ¨ -T/SR Slo-bid ¨ Slo-Phyllin ¨ Theo-24 ¨ Theochron ¨ Theo-Dur ¨ Theolair ¨ Theolair ¨ -SR T-Phyl ¨ Uni-Dur ¨ Uniphyl ¨
Asthma Quick-Relief Medications - Generic name | Brand name
Short-Acting Beta 2 -Agonists
Inhaled albuterol	Airet ¨ Proventil ¨ Proventil HFA ¨ Ventolin ¨ Ventolin ¨ Rotacaps
bitolterol pirbuterol terbutaline	Tornalate ¨ Maxair ¨ Brethaire ¨; Brethine ¨ & Bricanyl ¨ (tablets only)
Anticholinergics
Inhaled ipratropium bromide	Atrovent ¨
Steroids: Tablets or liquids
methylprednisolone	Medrol ¨
prednisone	Prednisone Deltasone ¨ Orasone ¨ Liquid Pred ¨ Prednisone Intensol ¨
prednisolone	Prelone ¨ Pediapred ¨

Immunotherapy

Immunotherapy consists of determining what substances a person is allergic to and desensitizing them to the allergen by administering periodic shots of the allergen.

According to the American Academy of Allergy and Immunology, approximately 33 million injections are given per year in the United States. Immunotherapy appears to be effective for the treatment of allergic rhinoconjunctivitis (runny nose and watery eyes due to allergy) and for insect sting allergies.

Is not routinely recommended (nor proven effective) for treatment of asthma, particularly severe asthma. There is healthy debate on the effectiveness of Immunotherapy in the treatment of asthma, with opinions varying from "effective" to "completely ineffective." However, some authorities argue that the risks of Immunotherapy exceed the benefits in patients with unstable asthma.

Classification of Asthma

An expert panel for the National Asthma Education and Prevention Program (NAEPP) recently issued new guidelines that recommend the use of a revised classification system for asthma. Based on these guidelines, asthma is classified as mild intermittent, mild persistent, moderate persistent and severe persistent. It is important to note that patients at any level of severity may have severe, lifethreatening exacerbations.

Low grade (not obviously noticeable) progressive inflammation occurs in the bronchial tubes of asthmatics not optimally treated. This means that when asthma symptoms occur there is much less room for safety because the bronchial airways are already narrowed.

It is very important to realize that all asthmatics except those with mild-intermittent asthma need to be taking daily anti-inflammatory medications even when they do not "feel" asthma symptoms.

How can I keep my Asthma under control?

Controlling your asthma requires:

• Understanding of what asthma is
• Having a written asthma management plan (keeping a copy of the plan with any care providers for children)
• Proper use of medications
• Regular use of peak flow meters
• Avoidance of asthma triggers.

Below is summary of potential triggers and control measures along with a "Traffic light color scheme" for using peak flow measurements to determine whether current asthma therapy is working.

When should I call my Doctor?

Call your doctor or go to an emergency room when:

• Asthma symptoms to worsen despite following a treatment plan
• When your peak flow is less than 50% of your best
• If you must use your bronchodilator more frequently than every 4 hours
• If you are having mild or moderate symptoms and are out of medication

Use of nonprescription inhalers, such as primatene, should be avoided. Prescription bronchodilators are more effective and safer.

Only prescription medications (corticosteroids) can treat moderate to severe inflammatory phase of asthma.

When should I call 911?

Call 911 immediately (not your doctors office) if:

• You are severely short of breath and do not have a bronchodilator inhaler available
• You are severely short of breath despite using a bronchodilator inhaler
• You have a normal (or close to normal) peak flow when well and it is now less than 200

DO NOT DRIVE OR HAVE ANYONE ELSE DRIVE YOU! Ambulance crews are equiped to give high flow breathing treatments and other lifesaving medications.

Where can I learn more about Asthma?

Contact these groups to learn more about asthma:

National Asthma Education and Prevention Program NHLBI Information Center
P.O. Box 30105, Bethesda, MD 20824-0105
301-251-1222
Internet: http://www.nhlbi.nih.gov/health/public/lung/asthma/asth_fs.htm

American Academy of Allergy, Asthma, and Immunology
800-822-2762
Internet: http://www.aaaai.org

American College of Allergy, Asthma, and Immunology
800-842-7777
Internet: http://www.acaai.org

American Lung Association
800-586-4872
Internet: http://www.lungusa.org

Asthma and Allergy Foundation of America
800-727-8462
Internet: http://www.aafa.org

New Strategies in the Medical Management of Asthma
KAREN M. GROSS, M.D.,CHARLES D. PONTE, PHARM.D.
from American Family Physician, July 1998
Internet: http://www.aafp.org/afp/980700ap/gross.html
(targeted to healthcare providers)

Citations

1. Asthma 2000 Monograph Series, Asthma Management: Current Clinical Practice; R.A. Nathan M.D. and S.L. Spector M.D. Eds. PP v, 1999.
   
   
2. Asthma and Bronchiolitis, S. H. Inkelis in Emergency Medicine- A Comprehensive Study Guide 4th Ed., Tintinalli, J.E, Ruiz, E. and R. L. Krome eds., PP 629-630, 1996.
   
   
3. Facts about Asthma - U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service National Institutes of Health National Heart, Lung, and Blood Institute
   NIH Publication No. 97-2339 Originally printed 1990 Revised September 1997

Top

Doctors Corner INternet Group, Inc. 1997-2004