Asthma Overview and Pathophysiology

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Questions and Answers

What role do eosinophils play in asthma pathology?

They inhibit the production of leukotrienes.

They produce cytokines that lead to muscle relaxation.

They release toxic granule products that can damage airway structures. (correct)

They primarily cause vascular dilation in asthma.

Which of the following triggers is NOT commonly associated with asthma?

Air Pollution

Low humidity (correct)

Exercise

Cigarette Smoke

What is a characteristic difference in asthma presentation among adults as compared to children?

New diagnosis in adults often occurs without prior childhood symptoms. (correct)

Exercise-induced symptoms are less common among adults.

All adults with asthma have a history of allergy.

Asthma symptoms are typically more severe in adults.

Which physical exam finding is associated with an acute exacerbation of asthma?

Pulsus paradoxus. Signup and view all the answers

What symptom is most characteristic of classic asthma presentation?

Episodic wheeze, especially on exhalation Signup and view all the answers

Which condition is commonly confused with asthma due to overlapping symptoms?

Chronic Obstructive Pulmonary Disease (COPD) Signup and view all the answers

Which factor is likely to lessen the probability of asthma diagnosis?

Onset of symptoms after age 50 Signup and view all the answers

What is an important consideration when assessing exercise-induced bronchospasm in children with asthma?

Occurs in up to 90% of children with asthma. Signup and view all the answers

Which of the following findings is NOT typically associated with a mild acute exacerbation of asthma?

No breath sounds Signup and view all the answers

In adults with asthma, what is typically true regarding the remission rates?

The likelihood of remission is lower compared to childhood asthma. Signup and view all the answers

What is primarily responsible for the chronic inflammation seen in asthma?

The involvement of many cells and cellular elements Signup and view all the answers

Which symptom is CLASSICALLY associated with asthma exacerbations, particularly occurring at night or early morning?

Chest tightness Signup and view all the answers

Which of the following findings would be least likely during a physical examination of a patient experiencing an acute asthma exacerbation?

Orthopnea Signup and view all the answers

What is the primary focus of a personalized asthma management plan?

Establishing individualized medication regimens Signup and view all the answers

When differentiating asthma from COPD, which of the following features is most indicative of asthma?

Presence of atopy or allergic conditions Signup and view all the answers

What characterizes the typical lung function test results in a patient with asthma?

Reversible airway obstruction Signup and view all the answers

In an acute asthma exacerbation, what is often the first-line treatment approach?

Short-acting beta-agonists Signup and view all the answers

Which of the following is NOT a common trigger for asthma exacerbations?

Hot weather Signup and view all the answers

What unique characteristic of asthma can be monitored over time to assess control of the condition?

Peak expiratory flow variations Signup and view all the answers

In the context of asthma management, which of the following approaches could be considered non-pharmacological?

Breathing exercises and relaxation techniques Signup and view all the answers

What genetic predisposition is specifically associated with Atopic Asthma?

Development of specific immunoglobulin E (IgE) antibodies Signup and view all the answers

Which cell type is primarily involved in the early phase reaction of asthma?

Mast cells Signup and view all the answers

What is a significant risk factor for asthma in children that is related to family history?

Having one asthmatic parent Signup and view all the answers

Which of the following statements correctly differentiates asthma from chronic obstructive pulmonary disease (COPD)?

Asthma is characterized by an early phase reaction, while COPD does not have this feature. Signup and view all the answers

Which component is a hallmark of late phase reactions in asthma?

Recruitment of eosinophils Signup and view all the answers

What nasal finding might be observed during a physical exam of a patient suspected of having asthma?

Polyps or swelling Signup and view all the answers

Which of the following management strategies is appropriate during an acute asthma exacerbation?

Using short-acting beta-agonists as rescue medication Signup and view all the answers

What factor significantly increases the likelihood of asthma in individuals with a family history?

Having two asthmatic parents Signup and view all the answers

What is a common consequence of airway remodeling in asthma?

Persistent airflow obstruction Signup and view all the answers

In asthma, what does the interaction between epithelial and mesenchymal cells primarily lead to?

Inflammatory response and remodeling Signup and view all the answers

Which physical examination finding indicates a severe asthma exacerbation?

Use of accessory muscles Signup and view all the answers

What is a typical spirometry finding in a patient with an asthma exacerbation?

Low FEV1/FVC ratio Signup and view all the answers

Which of the following symptoms is not typically associated with asthma during a physical exam?

Cervical lymphadenopathy Signup and view all the answers

In differentiating asthma from COPD, which characteristic is more likely to be present in asthma?

Significant wheezing during expiration Signup and view all the answers

What is an early sign of acute respiratory distress in an asthma patient?

Increased respiratory rate Signup and view all the answers

What aspect should not be overlooked when managing an acute asthma exacerbation?

Reassessing oxygen saturation levels Signup and view all the answers

How does tripoding position reflect the severity of an asthma exacerbation?

It indicates respiratory distress Signup and view all the answers

What value indicates hypoxemia that may be seen in an asthmatic with moderate/severe exacerbation?

SpO2 of 89% Signup and view all the answers

Which of the following findings is typically NOT associated with asthma when assessing lung function?

Persistent cough with sputum production Signup and view all the answers

Which clinical feature is typically more common in COPD than in asthma?

Chronic productive cough Signup and view all the answers

Study Notes

Asthma

Asthma is a chronic inflammatory disorder of the airways.
The chronic inflammation is associated with airway responsiveness that results in recurrent episodes of wheezing, breathlessness, chest tightness, and coughing.
Asthma symptoms are often worse at night or in the early morning.

Asthma Triggers

Air pollution
Allergens
Cigarette smoke
Exercise
Viral illness
Estrogen/hormones
Medications

Asthma Pathophysiology

In atopic asthma, there is a genetic predisposition to develop specific immunoglobulin E (IgE) antibodies directed against common environmental allergens.
There are intrinsic abnormalities in:
- Airway smooth muscle function
- Airway remodeling in response to injury or inflammation
- Interactions between epithelial and mesenchymal cells
Airway inflammation can be triggered by mast cell activation:
- Initial antigen exposure triggers the creation of allergen-specific IgE antibodies.
- These IgE antibodies bind to high-affinity receptors on mast cells (and basophils)
- Subsequent allergen exposure cross-links with IgE antibodies on mast cell surfaces.
- This triggers the rapid degeneration and mediator release of the mast cell, initiating an immediate hypersensitivity reaction.

Early and Late Phase Reactions to Asthma

Early Phase Reactions:
- Occur within several minutes of allergen inhalation by a sensitized individual.
- Characterized by bronchoconstriction due to release of mast cell mediators (histamine, prostaglandin D2, and cysteinyl leukotrienes).
Late Phase Reactions:
- Occur several hours after the early phase reaction.
- Characterized by recurrence of bronchoconstriction alongside recruitment of inflammatory and immune cells to the site of allergen exposure, including eosinophils, basophils, neutrophils, and helper, memory T-cells.

Childhood Asthma

Most common chronic disease in childhood in resource-rich countries.
Approximately 7.5% of US children had asthma in 2018.
Increasing prevalence in poor children and the Southern US.
Highest prevalence in Puerto Rican and non-Hispanic Black American children.
Boys are more likely to have asthma until puberty.
Approximately 80% of children with asthma develop symptoms before 5 years old.
Most common childhood asthma symptoms include: coughing, wheezing, breathlessness, chest pressure or tightness, and chest pain.
Cough can happen nocturnally, seasonally, or secondary to exposure.
Wheezing is common.
Seasonal symptoms, particularly with atopy, are prevalent.
Exercise-induced bronchospasm can occur in up to 90% of children with asthma.

Adult Asthma

New diagnosis as an adult (>20 years).
Can be persistent or recurrent since childhood.
New diagnosis as an adult occurs in approximately half of adults with asthma.
Non-immune factors are more common in adults.
Lower remission rate in adults.
There is a blurring of asthma vs. COPD in those with a history of smoking and a new diagnosis at an older age.

Classic Asthma Presentation

Episodic wheezing (high-pitched whistling sound, usually upon exhalation)
Episodic coughing (often worse at night)
Episodic shortness of breath or difficulty breathing
Episodic chest tightness
Characteristic triggers

Factors That Lesson Probability of Asthma:

Lack of improvement following anti-asthmatic medications.
Onset of symptoms after 50 years old.
Concomitant symptoms such as chest pain, lightheadedness, syncope, or palpitations.
History of cigarette smoking.

Physical Exam Findings

Wheezing may not be present between episodes or mild exacerbations.
Rhinitis and nasal polyps are possible.

Acute Exacerbation

Tachypnea, tachycardia, prolonged expiratory phase
Expiratory (and inspiratory) wheezing
Tripoding or hunched shoulders
Dyspnea on exertion
Accessory muscle use
Pulsus paradoxus (inspiratory decrease in systolic arterial pressure)
Diaphoresis
Mental status changes (EMERGENCY)
No breath sounds (EMERGENCY)

Physical Exam Findings - No/Mild Acute Exacerbation

VS: 120/76, HR 72, RR 14, SpO2: 96%, and Temp 98.6 F.
General: Alert and oriented x 3.

Physical Exam Findings - Moderate/Severe Acute Exacerbation

VS: 110/66, HR 136, RR 32, SpO2: 89%, and Temp 98.6 F.
General: Alert and oriented x 3. Acutely ill-appearing, in moderate respiratory distress.
Neck: No cervical lymphadenopathy. Trachea midline. Negative JVD.
HENT: Normocephalic and atraumatic. No erythema or exudates in the pharynx. No nasal discharge.
CV: Tachycardia with no murmurs, rubs, or gallops.
Pulm: Tachypnea. Intercostal and suprasternal accessory muscles use. Significant expiratory and inspiratory wheezes are noted on auscultation on posterior and anterior lung fields with prolonged expiratory phase. Tripod positioning. Speaking in 1-2 words sentences.
Skin: No rashes or bruising.

Asthma Epidemiology

Prevalence: 25.1 million (7.8%) of the population in 2019.
Mortality: 10.7 deaths per million (3,524 deaths) in 2019.

Asthma Risk Factors

Overall Risk Factors:
- Maternal age < 30 years
- Prenatal exposure to maternal smoking
- Prematurity
- Family history of asthma
 - 2.6x more likely to have asthma if one parent has asthma
 - 5.2x more likely to have asthma if both parents have asthma
Childhood Risk Factors:
- Males (until puberty)
- Atopy
- Allergen exposure
- Air pollution exposure
- Obesity
- Early puberty
Adolescent/Adult Risk Factors:
- Obesity
- Tobacco smoke exposure
- Occupational exposures
- Atopy/Rhinitis

Interpreting Spirometry

Step 1: Determine if FEV1/FVC is low (<70%).
Step 2: Perform bronchodilator challenge (if FEV1/FVC <70%).
- If FEV1 increases by ≥12% and ≥200 mL, it is suggestive of asthma responsiveness.
Step 3: Evaluate airflow limitation severity based on FEV1 (% predicted).

Asthma Exacerbation Management

Mild Exacerbation
- Short-acting beta-agonist (SABA) inhaler as needed.
Moderate Exacerbation
- SABA plus inhaled corticosteroids (ICS).
- Consider oral corticosteroids.
Severe Exacerbation
- If symptoms are not improving with therapy, consider:
 - Higher dose of SABA and ICS.
 - Nebulizer treatment with SABA and ICS.
 - Oxygen therapy.
 - Hospitalization if necessary:
 - Increased respiratory distress
 - Significant decrease in mental status
 - Worsening hypercapnia, SpO2 <90%.
 - Tripoding, unable to recline.

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Description

This quiz explores the chronic inflammatory disorder of asthma, focusing on its symptoms, triggers, and underlying pathophysiological mechanisms. Delve into the genetic and environmental factors that contribute to asthma and learn how airway inflammation occurs. Perfect for students seeking to understand respiratory health.