A 16-year-old student has a long history of bronchial asthma and has experienced several severe asthmatic attacks during the school year. The school nurse is required to administer 0.2 mL of 1/1000 solution of epinephrine SC during an asthma attack. How does the school nurse evaluate the effectiveness of this intervention?

A side effect of epinephrine is fatal ventricular fibrillation owing to its effects on cardiac stimulation. Medications used to treat asthma are designed to decrease bronchospasm, not to increase expectorate of secretions. Epinephrine decreased inspiratory difficulty by stimulating α-, β1, and β2-receptors causing sympathomimetic stimulation (e.g., bronchodilation). The person with asthma fights to inspire sufficient air thus increasing respiratory rate.