Exercise Induced Asthma

Definition/Description

Asthma is a reversible obstructive lung disease caused by increased reaction of the airways to various stimuli. It is a chronic inflammatory condition with acute exacerbations that can be life-threatening if not properly managed.[1]

Prevalence

Fifteen million persons of all ages are affected by asthma in the United States. This represents a 61% increase over the last 15 years with a 45% increase in mortality during the last decade. Women are affected more than men, accounting for about 60% of the nearly 18 million cases of adult asthma. Hormones are thought to be a be a possible cause for this increase in incidence in women.[1]

Characteristics/Clinical Presentation

Anytime a client experiences SOB, wheezing, and cough and comments, “I’m more out of shape than I thought,” the therapist should ask about a past medical history of asthma and review the list of symptoms with the client.[1]

Exercise-induced asthma symptoms can include:
Coughing
Wheezing
Shortness of breath
Chest tightness or pain
Fatigue during exercise
Poor athletic performance

Generally, many of the symptoms of exercise induced asthma begin after a few minutes of beginning exercise. It is possible that these symptoms will progress for as many as 10 minutes after concluding exercise.[2]


Other general signs and symptoms of asthma include:

Listen for:
•Wheezing, however light
•Irregular breathing with prolonged expiration
•Noisy, difficult breathing
•Episodes of dyspnea•Clearing the throat (tickle at the back of the throat or neck)
•Cough with or without sputum production, especially in the absence of a cold and/or occurring 5 to 10 minutes after exercise

Look for:
•Skin retraction (clavicles, ribs, sternum)•Hunched-over body posture; inability to stand, sit straight, or relax
•Pursed-lip breathing
•Nostrils flaring
•Unusual pallor or unexplained sweating

Ask about:
•Restlessness during sleep
•Vomiting
•Fatigue unrelated to working or playing[1]

Associated Co-morbidities

 
One co-morbidity of asthma is status asthmaticus. This is a severe, lifethreatening complication of asthma. With severe bronchospasm the workload of breathing increases five to ten times, leading to acute cor pulmonale. When air is trapped, a severe paradoxic pulse develops as venous return becomes obstructed. This condition can be recognized as a blood pressure drop of more than 10 mm Hg during inspiration. Additionally, pneumothorax can also develop. If status asthmaticus continues, hypoxemia worsens and acidosis begins. If the condition is untreated or not reversed, respiratory or cardiac arrest will occur.  Needles to say, an acute asthma episode may lead to a medical emergency.[1]

Adults with asthma are found to have significantly more comorbidities than the general population. These include respiratory infections and allergic rhinitis. High impact/high prevalence chronic conditions such as depression have also been found in one out of four adults with asthma. Children suffering from asthma were found to have fewer comorbidities than adults, but 12.6% had an associated chronic medical condition. The most prevalent co-morbidities found in adults with asthma are time-limited minor infections, while others with a high impact and/or high prevalence are depression, hypertension, diabetes, ischemic heart disease, degenerative joint disease, cardiac arrhythmia, cancer, congestive heart failure, cerebrovascular disease and COPD.[3]

Medications

Medications for exercise induced asthma include both short and long acting pharmaceuticals.
Short acting drugs are generally used for asthma attacks requiring an immediate response and often include:
Albuterol (ProAir HFA, Ventolin HFA)
Levalbuterol (Xopenex HFA)
Pirbuterol (Maxair Autohaler)
Ipratropium (Atrovent)

Long acting medications are used daily generally when attacks happen frequently, and short acting drugs have no affect on exercise induced asthma. These drugs include:

Fluticasone (Flovent Diskus, Flovent HFA)
Budesonide (Pulmicort Flexhaler)
Mometasone (Asmanex Twisthaler)
Triamcinolone (Azmacort)
Flunisolide (Aerobid)
Beclomethasone (Qvar)
Montelukast (Singulair)
Zafirlukast (Accolate)
Zileuton (Zyflo, Zyflo CR)
Theophylline (Theo-24, Elixophyllin)
Salmeterol (Serevent Diskus)
Formoterol (Foradil Aerolizer)

Combined long acting medication:
Fluticasone and Salmeterol (Advair Diskus)
Budesonide and Formoterol (Symbicort)
Mometasone and Formoterol (Dulera)[2]

Diagnostic Tests/Lab Tests/Lab Values

There are many tests that can determine the health of your lungs, or isolate asthma as a possible diagnoses. Some of these tests include:

Lung function test, also known as spirometry. 
 This is the preferred test for diagnosing asthma and measure the quality of breathing ability. The patient's test values are compared to     standardized values based on age, sex , and gender. If test values are abnormal the patient may inhale a bronchodilator drug before retaking the spirometry test. If breathing improves significantly, it's likely asthma could be a diagnoses.

Exercise challenge test.
 This test is used to see how exercise affects your lung function and is a more functional form of testing because it looks at the lungs ability to perform while at work. Pre and post tests are completed as the patient exercises for typically 6-8 minutes on a treadmill or other stationary workout machine.

Peak flow measurement test.
 This test is performed by breathing though a device which measures the velocity at which you can force air out of your lungs. The slower you exhale, the worse your asthma. Typically, the patient would breath into this device pre and post exercise.

Methacholine (Provocholine) challenge.
 To perform a methacholine challenge test, the patient would inhale a small amount of methacholine mist and any change in asthma symptoms are noted. Lung function is tested before and after methacholine is administered to determine the extent to which it affects breathing ability. Challenge testing may also performed using cold air, mannitol or histamine.[2]


Etiology/Causes

 The causes of exercised induced asthma aren't entirely known. Asthma and other atopic disorders are the result of complex interactions between genetic predisposition and multiple environmental influences. The marked increase in asthma prevalence in the last 3 decades suggests environmental factors as a key contributor in the process of allergic sensitization. [1]
 Factors that can trigger or worsen exercise-induced asthma include:

  Cold air
  Dry air
  Air pollution such as smoke or smog
  High pollen counts
  Having a respiratory infection such as a cold
  Chemicals, such as chlorine in swimming pools

 No exercise in particular must be avoided if a patient has exercise induced asthma. It is important to note, however, activities that cause the patient to breathe harder are more likely to trigger symptoms.[2]

Systemic Involvement

 Asthma can affect the entire pulmonary system. Often times the lungs become hyperreactive resulting in an exaggerated response to allergens and other irritants. In response, the muscles of the airway constrict, making the ability to breathe more challenging. As this hyperactive response occurs, so also does the process of inflammation. This causes the air passages to become swollen and the cells lining the passages to produce excess mucus, further impairing breathing.[1]

Medical Management (current best evidence)

Prevention:
American Academy of Allergy, Asthma, and Immunology (AAAAI) promotes utilization of self-management and prevention strategies for patients with asthma. A daily asthma management plan, as well as other information and resources, can be found on the AAAAI website.[1] [4]

'Diagnosis:'

Exercise-Induced Bronchospasms (EIB) is often diagnosed based on the patient’s history of the following symptoms: cough, shortness of breath, chest pain or tightness, wheezing, or endurance problems during exercise. However, EIB has been shown to be misdiagnosed when based on patient history alone. Pulmonary function testing, involving a cardiovascular exercise challenge at 80% of heart rate maximum, is a primary diagnostic tool often used to augment clinical symptom findings. Diagnosis of EIB is indicated with 15-percent decrease in the patient’s PEF or FEV1[5].

Management:

If addressed and treated appropriately, exercise-induced asthma should not restrict one’s ability to fully participate in vigorous physical activity. Furthermore, adequate asthma control should allow for a patient to participate in any activity of choice without experiencing asthma symptoms[5]. Management of EIB should include identifying any allergens the patient may have, educating the patient on avoiding asthma triggers, and use of asthma medications, when necessary[1]. The EPR 3 Guidelines for Diagnosis and Management of Asthma recommend the following treatments for the medical management of EIA[5]:

Long-term Pharmacotherapy (if appropriate): 
Anti-inflammatory medications, such as inhaled corticosteroids used to suppress airway inflammation, have been proven to decrease the frequency and severity of EIB when used on a daily basis for long-term control of asthma. Long-term control therapy is recommended for patients with poorly controlled symptoms, including frequent, severe episodes of EIB[5]

Treatments Prior to Exercise[5]:

1. Inhaled beta2-agonists:

  • Short Acting Beta Agonists (SABA), often called ‘rescue inhalers’, are used acutely before exercise to control symptoms up to 2-3 hours
  • Long Acting Beta Agonists (LABA) are used in conjunction with inhaled corticosteroids to provide additional protection from asthma   symptoms for up to 12 hours. LABA are not indicated for daily use but should be used as a pretreatment to exercise.

2. Leukotriene Receptor Antagonists (LTRAs): are medications used for allergy treatment and to prevent asthma symptoms. LTRAs have a longer onset of action and may take hours to provide symptom relief.

3. Exercise Warm Up: A period of warming up before exercise may help to decrease symptoms associated with EIB

4. Protection Against Cold: Wearing a scarf over the mouth prior to/during activity may help to decrease cold-induced EIB

Physical Therapy Management (current best evidence)

Acute Management:
Because EIB is triggered by exercise, physical therapists may be the first to identify asthma symptoms in a patient with undiagnosed EIB. For this reason, physical therapists must be aware of the associated signs and symptoms of EIB, as well as any red flags that may indicate a need for medical referral and treatment. If a patient has an acute asthma attack during therapy, the physical therapist should assess the severity of the attack, then position the patient in high Fowler’s position for diaphragmatic and pursed-lip breathing, if appropriate. If the patient has an inhaler available, the physical therapist should provide assistance to allow the patient to self-administer the medication, while helping the patient to relax[6].


Long-term Management
There are several factors that can deter patients with EIA from exercising, one being the belief that exercise is detrimental to their condition. Although there is insufficient evidence to support breathing exercises or inspiratory mm training in patients with asthma, there is strong evidence to support the benefits of physical activity for cardiovascular training in this patient population[6].Therefore, physical therapists can play a large role in management of care by providing patient education and exercise prescription.


The Preferred Practice Patterns for this patient population[6], according to the Physical Therapy Guide to Practice[7], include:

  • Pattern 6B: Impaired Aerobic Capacity/Endurance Associated With Deconditioning
  • Pattern 6C: Impaired Ventilation, Respiration/Gas Exchange, and Aerobic Capacity/Endurance Associated With Airway Clearance Dysfunction
  • Pattern 6E: Impaired Ventilation and Respiration/Gas Exchange Associated With Ventilatory Pump Dysfunction or Failure
  • Pattern 6F: Impaired Ventilation and Respiration/Gas Exchange Associated With Respiratory Failure


Exercise and Medication:

Bronchodilators should be self-administered with a meter-dose inhaler (MDI) about 20-30 minutes prior before the patient participates in exercise. Mild stretching and a warm-up to exercise should also be performed during that time to help prevent the onset of asthma symptoms. Physical therapists must be aware of any adverse side effects or drug toxicity associated with asthma medications. Some symptoms that may suggest drug toxicity include nausea and vomiting, tremors, anxiety, tachycardia, arrhythmia, and hypotension. If the patient exhibits asthma symptoms during exercise that are not controlled with current medication, the physical therapist should notify the patient’s physician to alter the dosage[6].


Vital Signs:


It is important for the physical therapist to monitor the patient’s vital signs before, during and after exercise, to detect any abnormal changes in bronchopulmonary function. Auscultation of the lungs should be done routinely to detect any abnormal breath sounds, wheezing, or presence of rhonchi. Red flags that may indicate worsening asthma or drug toxicity can include tachypnea (increased respiratory rate above normative values), diarrhea, headache and vomiting. Asthma-related hypoxemia may be indicated with an abnormal rise in the patient’s blood pressure[6]


Other Considerations:


Decreased bone mass density has been associated with long-term use of inhaled corticosteroids in patients with moderate to severe asthma. This chronic corticosteroid use also has an associated increased risk of fracture, in particular asymptomatic vertebral fractures. Physical therapists should be aware of the patient’s medication history and take precautions when exercising patients who may be at risk for fractures. Physical therapy can enhance medical management and play important role in the care of patients with status asthmaticus. Physical therapists can teach the patient various coughing, breathing, and positioning techniques to help clear secretions, reduce hypoxemia and improve V/Q matching. Aggressive treatments, such as forceful percussion, should be avoided in this population to prevent triggering of bronchospasms[6]

Differential Diagnosis

The most common differential diagnoses of EIB include[8]:

  • Vocal Cord Dysfunction
  • Laryngeal/tracheal processes
  • Respiratory tract infection
  • Gastro-esophageal reflux
  • Hyperventilation syndromes

EIB may also be associated with underlying conditions, such as[9]:

  • COPD
  • Obesity
  • Pectus Excavatum
  • Diaphragmatic paralysis
  • Interstitial Fibrosis

Case Reports/ Case Studies

EXERCISE-INDUCED ASTHMA CASE STUDY

PAGES 858-876

PHYSICAL THERAPY FOR CHILDREN (2005)

Suzann K. Campbell, Robert J. Palisano, Margo Orlin and Darl W. Vander Linden

CHAPTER 28: ASTHMA- MULTISYSTEM IMPLICATIONS;

SECTION IV: MANAGEMENT OF CARDIOPULMONARY CONDITIONS

CASE STUDY: PAGES 858-876[10]






Resources

1. The Community Guide - Asthma Control

http://www.thecommunityguide.org/asthma/index.html

2. Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma Full Report

http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm

3. Recommendations from the Task Force on Community Preventive Services to decrease asthma morbidity through home-based, multi-trigger, multicomponent interventions. (Community Guide Recommendation)

http://www.thecommunityguide.org/asthma/supportingmaterials/Asthma%20Task%20Force%20recs.pdf

4. American Academy of Allergy, Asthma and Immunology Website

http://www.aaaai.org/home.aspx

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Goodman CC, Snyder TE. Differential Diagnosis for Physical Therapists, Screening for Referral. W B Saunders Company; 2012. 298
  2. 2.0 2.1 2.2 2.3 "Exercise-induced asthma." Mayo Clinic. N.p., n.d. Web. 25 Mar. 2014. <http://www.mayoclinic.org/diseases-conditions/exercise-induced-asthma/basics/definition/con-20033156>.
  3. Boulay, Marie-Ève, and Louis-Philippe Boulet. "Asthma-related Comorbidities." Informahealthcare.com. Centre De Recherche De L’Institut Universitaire De Cardiologie Et De Pneumologie De Québec, 2001. Web. 23 Mar. 2014. <http%3A%2F%2Finformahealthcare.com%2Fdoi%2Fpdf%2F10.1586%2Fers.11.34%3FnoFrame%3Dtrue>.
  4. The American Academy of Allergy, Asthma and Immunology. Accessed March 25, 2014 at http://www.aaaai.org/home.aspx
  5. 5.0 5.1 5.2 5.3 5.4 Expert Panel Report 3 (EPR3): Guidelines for the Diagnosis and Management of Asthma. SECTION 4, MANAGING ASTHMA LONG TERM—SPECIAL SITUATIONS. Accessed March 25, 2014 at http://www.nhlbi.nih.gov/guidelines/asthma.
  6. 6.0 6.1 6.2 6.3 6.4 6.5 Goodman CC, Snyder TE. Differential Diagnosis for Physical Therapists, Screening for Referral. W B Saunders Company; 2012.772-774
  7. APTA Guide to Physical Therapist Practice-Online. Cardiovascular/Pulmonary Preferred Practice Patterns. http://guidetoptpractice.apta.org/content/current
  8. Schumacher Y, Pottgiesser T, Dickhuth H. Exercise-induced bronchoconstriction: Asthma in athletes. International Sportmed Journal [serial online]. December 2011;12(4):145-149. Available from: SPORTDiscus with Full Text, Ipswich, MA. Accessed March 25, 2014.
  9. Weiler JM, Anderson SD, Randolph C, et al. Pathogenesis, prevalence, diagnosis, and management of exercise-induced bronchoconstriction: a practice parameter. Ann. Allergy. Asthma Immunol. 2010;105(6 Suppl):S1–47. Available at: http://www.ncbi.nlm.nih.gov/pubmed/21167465. Accessed March 25, 2014.
  10. Campbell S, Palisano R, Orlin M, and Vander Linden, D. Asthma: Multisystem Implications. Case Study: Mary Massery PT, DPT. In: Physical Therapy for Children 3rd ed. 2005:858-876. Accessed March 25, 2014. Online. http://www.masserypt.com/images/pdfs/MasseryCh28AsthmaCampbellPedPTTextbook2006.pdf