Exercise-Induced Asthma J45.990 493.8

 

synonyms: Exercise-Induced Asthma (EIA), Exercise-Induced Bronchospasm (EIB)

EIA ICD-10

  • J45.990 Exercise induced bronchospasm

EIA ICD-9

  • 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.

EIA Anatomy

  • 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 Complications

  • Asthmatic attack

EIA Follow-up Care

  • Generally referred to primary care or pulmonary for continued management.

EIA Review References