Question

The primary physiological alteration in the development of asthma is: A. Bronchiolar inflammation and dyspnea B. Hypersecretion of abnormally viscous mucus C. Infectious processes causing mucosal edema D. Spasm of bronchiolar smooth muscle

Short answer

Answer: Spasm of bronchiolar smooth muscle.

Step-by-step solution

Analyze Option A

Bronchiolar inflammation and dyspnea are indeed associated with asthma. Inflammation contributes to the narrowing of the airways, leading to difficulty in breathing, known as dyspnea. However, we should analyze the other options as well, to determine if this is the primary alteration responsible for the development of asthma.

Analyze Option B

Hypersecretion of abnormally viscous mucus is a characteristic feature of another respiratory condition called cystic fibrosis, not asthma. Therefore, this cannot be the primary physiological alteration for asthma development.

Analyze Option C

Infectious processes causing mucosal edema are more related to respiratory infections, such as bronchitis and pneumonia. While these infections can cause asthma exacerbations or worsen asthma symptoms in some individuals, they are not the primary physiological alteration related to the development of asthma. Thus, we can eliminate this option.

Analyze Option D

Spasm of bronchiolar smooth muscle is one of the primary hallmarks of asthma. When the smooth muscle surrounding the bronchioles tightens up due to various triggers, it causes the airways to constrict and makes breathing difficult. This narrowing of airways is a characteristic feature of asthma.

Choose the correct answer

After analyzing all the options, we can safely say that Option D - Spasm of bronchiolar smooth muscle is the primary physiological alteration in asthma development. Option A is a notable feature of asthma, but bronchiolar smooth muscle spasm is more characteristic of the condition. Therefore, the correct answer is Option D.

Key concepts

Bronchiolar Inflammation

Bronchiolar inflammation is a significant aspect of asthma. This inflammation results from the immune system's response to certain triggers, such as allergens or irritants. When bronchioles, the small airways in the lungs, become inflamed, they swell and restrict airflow.
The inflammation can lead to the production of excess mucus, compounding the blockage. As a result, individuals experience symptoms like coughing and wheezing, commonly associated with asthma.

• Narrowing of airways due to swelling
• Increased mucus production
• Triggered by allergens and irritants

Dyspnea in Asthma

Dyspnea, or difficulty in breathing, is a troubling symptom of asthma. This feeling of shortness of breath occurs because the airways are constricted, limiting the amount of air that can move in and out of the lungs.
Asthma patients often describe dyspnea as a feeling of tightness in the chest or being unable to catch their breath.
Sometimes, dyspnea in asthma can be mild, but it can escalate into severe episodes if not managed properly.

• Caused by restricted airflow
• Accompanied by chest tightness
• Varies in severity

Bronchiolar Smooth Muscle Spasm

Spasm of the bronchiolar smooth muscle is a hallmark feature of asthma. These muscles encircle the bronchioles and react to asthma triggers by tightening. This reaction leads to significant narrowing of the airways.
When these spasms occur, it severely restricts airflow, causing wheezing and breathlessness.
Spasms can be triggered by numerous factors, including:

• Environmental allergens
• Cold air
• Exercise
• Strong emotions or stress

Knowing and avoiding these triggers can help in managing asthma symptoms effectively.

Physiological Alterations in Asthma

Asthma is characterized by a complex set of physiological alterations that affect the airways. The primary alteration involves the spasm of bronchiolar smooth muscle, leading to airway constriction.
Other important changes include bronchiolar inflammation and increased mucus production, both contributing to narrowed airways.
The physiological changes associated with asthma make it crucial to have a comprehensive management plan, including medication and lifestyle adaptations to control and prevent asthma attacks.

• Smooth muscle spasm causing airway narrowing
• Inflammation adding to airway obstruction
• Mucus production further restricting airflow

Asthma management aims to alleviate and prevent these various alterations, ensuring better respiratory health for individuals.