Final answer:
Bronchiolar smooth muscle relaxants are medications that cause bronchodilation, increasing air flow and alleviating symptoms of constricted airways such as those experienced during an asthma attack.
Step-by-step explanation:
Bronchiolar smooth muscle relaxants are medications that cause bronchodilation, thereby improving air flow and relieving the wheezing. Bronchodilation refers to the widening of the bronchioles, the small branches of the respiratory tree, as a result of the relaxation of the surrounding smooth muscle tissue. When the smooth muscles around the bronchioles relax, the airways are allowed to expand, increasing the flow of air through the lungs. This is particularly helpful in conditions like asthma, where the bronchioles can become narrowed due to muscle contraction. Environmental triggers such as dust, pollen, pet dander, and various other factors can induce bronchoconstriction, leading to asthma attacks, which are characterized by symptoms such as difficulty breathing, chest tightness, and wheezing. Beta-2 adrenergic receptor agonists are an example of such medications that can be used to treat asthma by stimulating bronchodilation.