Review Question - QID 103615

This patient with dyspnea, wheezing, and use of accessory muscles of respiration has a severe asthma exacerbation. The next appropriate step in management, after supplemental oxygen, is administration of an inhaled short-acting beta-2 agonist combined with an anticholinergic agent, such as albuterol-ipratropium.

The first step in the management of acute asthma exacerbation is correction of hypoxemia with oxygen administration. This should be immediately followed by beta-2 agonists combined with an anticholinergic agent, which together act synergistically to cause bronchial smooth muscle relaxation and result in airway dilation. Most patients with severe asthma exacerbation are often given intravenous corticosteroids as well. However, steroid medications typically require several hours to take affect. For this reason, the first priority is administration of more rapidly acting inhaled bronchodilators.

Hasegawa et. al review the management of acute asthma exacerbation in the emergency department. They discuss the medications used in the initial resuscitation of patient's with severe asthma, and note that inhaled bronchodilators such as albuterol-ipratropium are the most appropriate first step in management.

Incorrect Answers:
Answer 1: Intravenous magnesium sulfate has bronchodilator activity in acute asthma via bronchial smooth muscle relaxation. It is indicated in patients who have life-threatening exacerbations or whose exacerbation remains severe after use of bronchodilator and corticosteroid therapy, but it is not the most appropriate initial step in management.

Answer 2: Intravenous methylprednisolone or other steroid medications are commonly utilized in the management of asthma exacerbation. However, therapeutic effects usually take several hours. Therefore, the first priority is administration of more rapidly acting bronchodilators.

Answer 3: Intravenous theophylline is no longer commonly used in the management of acute asthma exacerbation due to its narrow therapeutic index and side effect profile.

Answer 5: Oral montelukast, a leukotriene receptor antagonist, reduces synthesis of leukotrienes that cause airway inflammation. It is sometimes used in the long term management of asthma but is not utilized in the initial management of severe asthma exacerbation.

Bullet Summary:
The most appropriate initial step in management of severe asthma exacerbation is administration of a nebulized bronchodilator, such as combined albuterol-ipratropium.