A 10-year-old boy who is having an acute asthmatic attack is brought to the emergency department…

A 10-year-old boy who is having an acute asthmatic attack is brought to the emergency department by his parents. The boy is observed to be sitting up and struggling to breathe. His breathing is accompanied by use of the accessory muscles, a weak cough, and audible wheezing sounds. His pulse is rapid and weak and both heart and breath sounds are distant on auscultation. His parents relate that his asthma began to worsen after he developed a “cold,” and now he doesn’t even get relief from his “albuterol” inhaler.

A. Explain the changes in physiologic function underlying this boy’s signs and symptoms. B. The boy is treated with a systemic corticosteroid and inhaled anticholinergic and b2 -adrenergic agonist and then transferred to the intensive care unit. Explain the action of each of these medications in terms of relieving this boy’s symptoms