Bronchodialators

Mechanism of Action

• Inhibit bronchial smooth muscle constriction in patients with asthma or COPD.

Treatment

• Asthma
• Chronic Obstructive Pulmonary Disease (COPD)
• Emphysema
• Severe allergic reactions (anaphylaxis)
  • Epinephrine injection only

Types Bronchodilators

• β2-adrenergic agonist
• Xanthine Derivatives
• Anticholinergic

Mechanism of Action

• Inhibit bronchial smooth muscle constriction in patients with asthma or COPD.
• Some bronchodilators also help to clear mucus and reduce inflammation in the lungs

Effect on Exercise and Rest

• Resting Heart Rate
  • No effect on heart rate (ACSM 2013)
  • Varies depending on class of bronchodilotor (Gladson 2011)
• Blood Pressure
  • No effect on blood pressure (ACSM 2013)
  • Varies depending on class of bronchodilotor (Gladson 2011)
• Exercise capacit
  • No effect on exercise capacity (ACSM 2013)
    • Limited by bronchospasm
  • Varies depending on class of bronchodilotor (Gladson 2011)
• No effect on ECG (ACSM 2013)
• Decrease in Dyspnea (Gladson 2011)
• Increase in exercising partial pressure of oxygen (EpaO) (Gladson 2011)

Sympathomimetics (β-Mimetics)

Mechanism of Action

• Inhibit bronchial smooth muscle constriction in patients with asthma or COPD
• Inhibits inflammatory cells in the airway from releasing inflammatory mediators and cytokines

Names

• Short-acting β2 agonists
  • Albuterol or Salbutamol (ProAir, Proventil, ProAir RespiClick, and Ventolin)
  • Bitolterol (Tornalate)
  • Epinephrine injection (Adrenaclick, Adrenalin, EpiPen, Twinject Auto-Injector)
  • Fenoterol (Berotec)
  • Isoprenaline or Isoproterenol (Isuprel)
  • Levosalbutamol or Levalbuterol (Xopenex)
  • Orciprenaline or Metaproterenol (Alupent)
  • Pirbuterol (Maxair)
  • Procaterol (Meptin, Onsukil, Masacin, Procad)
  • Ritodrine (Yutopar)
  • Terbutaline (Bricanyl)
• Long-acting β2 agonists
  • Arformoterol (Brovana)
  • Bambuterol (Bambec)
  • Clenbuterol (Dilaterol, Spiropent)
  • Formoterol (Foradil, Oxis, Perforomist)
  • Salmeterol (Serevent)
• Ultra-long-acting β2 agonists
  • Abediterol
  • Carmoterol
  • Indacaterol (Arcapta Neohaler, Onbrez Breezhaler)
  • Olodaterol (Striverdi Respimat)
  • Vilanterol
    • with Umeclidinium bromide (Anoro Ellipta)
    • with Fluticasone furoate (Breo Ellipta, Relvar Ellipta)

Effect on Exercise and Rest

• Increased resting heart rate (Gladson 2011)
• Increased blood pressure (Gladson 2011)
• Exercise Capacity (Gladson 2011)
  • Short-acting increase exercise capacity
  • Longer-acting may decrease exercise capacity
• Decreased resting partial pressure of oxygen (RpaO) (Gladson 2011)
• Increased exercising partial pressure of oxygen (EpaO) (Gladson 2011)

Xanthine Derivatives

Mechanism of Action

• Nonselective phosphodisterase enzyme inhibitor
• Dilates bronchi by blocking the action of phosphodiesterase (PDE) enzymes

Names

• Theophylline (Theo 24, Elixophyllin, Uniphyl, Theolair, Slo-Bid)
• Aminophylline (Aminophylline, Euphyllin, Phyllocontin, Somophyllin, Truphylline, Minomal)
• Dyphyline (Dilor, Lufyllin)

Effect on Exercise and Rest

• Increased resting heart rate (Gladson 2011)
• Increase or decrease in blood pressure (Gladson 2011)
• No change in exercise capacity (Gladson 2011)
• Increased exercising partial pressure of oxygen (EpaO) (Gladson 2011)

Anticholinergics

Mechanism of Action

• Blocks the effect of acetylcholine on airways and nasal passages, causing the muscles to relax and airways to dilate

Names

• Ipratropium (Atrovent)
• Tiotropium (Spiriva Respimat)
• Aclidinium (Tudorza Pressair)
• Umeclidinium (Incruse Ellipta)
• Glycopyrrolate (Seebri Neohaler)

Effect on Exercise and Rest

• Decrease resting heart rate (Gladson 2011)
• No change in blood pressure (Gladson 2011)
• Increase in exercise capacity (short-acting) (Gladson 2011)
• No change in resting partial pressure of oxygen (RpaO) (Gladson 2011)
• Increased exercising partial pressure of oxygen (EpaO) (Gladson 2011)

Other Effects

• Decreased exacerbations (Gladson 2011)
• Increased quality-of-life measures (Gladson 2011)
• Very low levels of adverse effects (Gladson 2011)

Bronchodilators for Exercise

• Effects of bronchodilators on exercise capacity in patients with COPD (Gladson 2011)
  • Anticholinergics have the most significant effect on exercise capacity with high dose therapies generally resulting in greater effects
  • Short-acting β2 sympathominetrics also have significant positive effects on exercise capacity
  • Longer-acting β2 sympathominetrics do not produce significant effects
  • Methylxanthines have negative effects on exercise capacity
  • An addition of a second bronchiodilator has no advantage in improving exercise capacity
  • Most bronchioddilators can reduce dyspnea, even in the absence of exercise capacity improvements
• Effects of bronchodilators on quality-of-life measures in patients with COPD (Gladson 2011)
  • Anticholinergics appear to improve quality-of-life measures more than long-acting bronchodilators
• Anticholinergics (compared to other classes of bronchodilators) in patients with COPD (Gladson 2011)
  • More effective in decreasing dyspnea
  • Have fewer central effects at rest
  • Better attenuate right heart afterloads during exercise
  • Have fewer adverse effects

Recommendations

• Exercise at the same time each day so drug plasma levels are consistent (Gladson 2011)
• Carry a rescue inhaler during exercise if it has been prescribed (Gladson 2011)
• Monitor for signs of right ventricular failure (Gladson 2011)

References

American College of Sports Medicine (2013). Guidelines for Exercise Testing and Prescription, William & Wilkins, 9, 401.

Gladson B (2011). Pharmacology for Rehabilitation Professionals, Elsevier Saunders (2) 490-492.