Objective 13: Describe Respiratory Changes and Long-Standing Structural Abnormalities in Bronchial Wall

Respiratory changes in asthma

Airway narrowing from inflammation, bronchoconstriction, and increased mucus production.

Airway lumen

The internal opening of the bronchial passage through which air moves.

Inspiration during asthma

Chest expansion may slightly increase the diameter of narrowed airways, allowing air to enter more easily.

Expiration during asthma

Naturally narrows airways further, making it difficult to move air out.

Prolonged expiration

Extended exhalation caused by increased airway resistance.

Accessory muscles of expiration

Muscles recruited to help force air out when normal expiration becomes difficult.

Air trapping in asthma

Occurs when narrowed airways prevent complete expiration.

Lung hyperinflation

Excessive air remains trapped in the lungs, increasing lung volume.

Residual volume in asthma

Increases because air cannot be completely exhaled.

Forced expiratory volume in asthma

Decreases because narrowed airways limit the speed and amount of air exhaled.

Wheezing in asthma

High-pitched sound produced by turbulent airflow through narrowed airways.

Dyspnea in asthma

Shortness of breath caused by increased respiratory effort and airflow obstruction.

Chest tightness in asthma

Sensation associated with bronchoconstriction and increased respiratory effort.

Severe asthma manifestations

Accessory muscle use, retractions, tachypnea, and possible hypoxemia.

Chronic airway inflammation

Persistent inflammatory activity that causes ongoing epithelial injury and airway abnormalities.

Eosinophils in chronic asthma

Inflammatory cells that contribute to persistent airway inflammation and tissue injury.

Epithelial injury

Repeated damage to the normal lining of the bronchial walls.

Impaired mucociliary function

Reduced ability of cilia to transport mucus out of the respiratory tract.

Mucus plugs

Accumulated secretions that obstruct bronchial passages.

Airway hyperresponsiveness

Exaggerated airway reaction to triggers, which may persist between acute attacks.

Long-term structural changes

Changes in bronchial wall structure and function resulting from repeated inflammation and injury.

Reversible airway narrowing

Acute narrowing caused by bronchoconstriction, edema, and mucus accumulation that can improve with treatment.

Persistent airway abnormalities

Long-standing changes from repeated inflammatory episodes that can make asthma harder to control.

What causes airway narrowing in asthma?

Inflammation, bronchoconstriction, and increased mucus production.

Why is inspiration sometimes easier than expiration during asthma?

Chest expansion during inspiration can slightly increase the diameter of narrowed airways.

Why is expiration more difficult during asthma?

Airways naturally become narrower during exhalation, increasing resistance and making air harder to expel.

What happens to expiration during an asthma episode?

It becomes prolonged because of increased airway resistance.

Why might a patient with asthma use accessory muscles during expiration?

To generate additional force to push trapped air out of narrowed airways.

What causes air trapping in asthma?

Narrowed airways prevent the lungs from completely emptying during expiration.

What happens to residual volume during asthma?

It increases because air remains trapped in the lungs.

What is lung hyperinflation?

Excessive air retention that increases lung volume.

What happens to forced expiratory volume during asthma?

It decreases because narrowed airways restrict the rate and amount of air exhaled.

Why does wheezing occur in asthma?

Air passes through narrowed bronchial passages, producing turbulent airflow.

What causes dyspnea in asthma?

Increased respiratory effort and difficulty moving air through obstructed airways.

What causes chest tightness during an asthma episode?

Bronchoconstriction and increased work of breathing.

What are signs of a severe asthma episode?

Accessory muscle use, retractions, tachypnea, and possible hypoxemia.

What causes long-standing structural abnormalities in bronchial walls?

Repeated episodes of chronic inflammation and epithelial injury.

Which inflammatory cells contribute to persistent airway inflammation in asthma?

Eosinophils.

How does chronic inflammation affect the bronchial epithelium?

Causes repeated injury and damage to the normal airway lining.

How does epithelial injury affect mucociliary function?

Interferes with ciliary activity and decreases mucus clearance.

What happens when mucus clearance becomes impaired?

Secretions accumulate and can form mucus plugs that obstruct airflow.

Why can airway hyperresponsiveness persist between asthma attacks?

Repeated inflammation and structural changes leave the airways unusually sensitive to triggers.

What is the difference between acute airway narrowing and long-standing structural abnormalities?

Acute narrowing results from bronchoconstriction, edema, and mucus; structural abnormalities develop from repeated inflammation and injury.

How can repeated asthma attacks make asthma harder to control?

They contribute to persistent inflammation, epithelial damage, impaired mucus clearance, and increased airway responsiveness.

A patient has an increased residual volume and prolonged expiration. What respiratory changes are occurring?

Air trapping and airflow obstruction caused by narrowed airways.

A patient has impaired ciliary function and frequent mucus plugging. What long-term asthma change explains this?

Repeated epithelial injury and impaired mucociliary clearance.

Why is controlling chronic airway inflammation important in asthma?

It helps prevent repeated injury and the development of persistent airway abnormalities.