synonyms: Exercise-Induced Asthma (EIA), Exercise-Induced Bronchospasm (EIB)
- 493.8 Other forms of asthma
EIA Etiology / Epidemiology / Natural History
- Affects @20% of elite summer athletes and @45% of elite winter athletes.
- Etiology: ariway dehydration, hypertonic airway fluid, inhaled irritants (chlorine/gas exhaust)
- EIA = chronic asthma exacerbated by exercise
- EIB = bronchospasm occuring only with exercise
- Diagnosis: based on PFTs, PEFR, FEV1. Baseline drop that is greater than or equal to 10%, on any postexercise measurement, indicates EIA. Mild=10-20% decrease. Moderate=20-40% decrease. Severe=40% decrease.
- Airway narrowing is primarily caused by contraction of bronchial smooth muscle.
EIA Clinical Evaluation
- Exercise induced cough, chest pain with exercise, fatigue with exercise, improvement in symptoms after warm up exercises.
EIA Xray / Diagnositc Tests
- PFTs, PEFR, FEV1. Baseline drop that is greater than or equal to 10%, on any postexercise measurement, indicates EIA. Mild=10-20% decrease. Moderate=20-40% decrease. Severe=40% decrease.
EIA Classification / Treatment
- Acute attack: PO/IV corticosteriods 60-80 mg er day for 5 days followed by steriod taper or Methylprednisolone 0.5-2.0mb/kg Q6hrs. Consider epinephrine 0.3ml of 1:1000 solution; albuterol 4-8 puffs Q20minutes x3; supplemental oxygen for severe acute attacks.
- Warmup with low-intensity exercise before practice or competition, inhaled beta-2 adrenoceptor agonists. Fish oils (contain eicosapentaenoic and docosahexaenoic acids) have anti-inflammatory affects which are often helpful for EIB (Mickleborough TD, Chest 2006;29:39). Fish oil diet = 20 capsules per day of a triglyceridic oil containing approximately 18% EPA (EPAX 3000 TG; Pronova Biocare; Lysaker, Norway; 160 mg of EPA per gram of triglyceride) and 12% DHA (100 mg of DHA per gram of triglyceride), with 1 to 2 mg of tocopherol per gram of triglyceride added, in 1,000-mg soft gel capsules (Mickleborough TD, Chest 2006;29:39).
- Salbutamol 20 minutes before exercise and prn (Short acting).
- Salmeterol or Formoterol 1 hour before exercise (long acting).
- Lekotrine antagonists (montelukast, zafirlukast): prevent last cell degranuation.
- Consider Nedocromil or cromolyn sodium
- Consider: antihistamines for associated seasonal allergies, immunotherapy for specific antigens.
- IOC mandates laboratory documented reduced FEV1 for approval for athletes to use beta-agonists.
EIA Associated Injuries / Differential Diagnosis
- Vocal cord dysfunction (inspiratory stripor with exercise that resolves with rest) (Parker JM, Clin Chest Med 2004;25:321).
- Cardiac disease
- Airway obstruction
- Pulmonary disease
EIA Follow-up Care
- Generally referred to primary care or pulmonary for continued management.
EIA Review References