NCLEX Review Guide: Asthma

Definition and Mechanism

• Asthma is a chronic inflammatory airway disorder characterized by airway hyperresponsiveness, reversible bronchoconstriction, and mucus hypersecretion. The pathophysiology involves a complex interaction between airway inflammation, intermittent airflow obstruction, and bronchial hyperresponsiveness.
• During an asthma attack, bronchospasm (contraction of bronchial smooth muscle), edema (mucosal swelling), and hypersecretion (excess mucus production) occur in response to various triggers, causing narrowed airways and difficulty breathing.

Inflammatory Response

• The inflammatory response in asthma involves multiple cell types including mast cells, eosinophils, T lymphocytes, neutrophils, and epithelial cells. These cells release inflammatory mediators like histamine, leukotrienes, and cytokines that perpetuate the inflammatory cascade.
• This chronic inflammation leads to bronchial hyperresponsiveness, where airways overreact to various stimuli that wouldn't affect healthy individuals.

Classic Symptoms

• The classic triad of asthma symptoms includes wheezing, cough, and dyspnea. Wheezing is typically expiratory and polyphonic (multiple pitches), though severe attacks may present with "silent chest" when airflow is too limited to produce wheeze.
• Other symptoms include chest tightness, prolonged expiratory phase, use of accessory muscles, tachypnea, tachycardia, and in severe cases, cyanosis and altered mental status.

Exacerbation Signs

• During an acute exacerbation, patients may exhibit tripod positioning (leaning forward with arms braced), intercostal retractions, nasal flaring, and paradoxical pulse (decrease in systolic BP during inspiration by more than 10 mmHg).
• Assessment findings include decreased oxygen saturation, decreased peak expiratory flow rate (PEFR), hyperresonance on percussion, and diminished breath sounds or adventitious sounds (wheezes, rhonchi).

Diagnostic Tests

• Pulmonary Function Tests (PFTs) are the gold standard for diagnosing asthma, showing reversible airflow obstruction. Key values include FEV1 (forced expiratory volume in 1 second), FVC (forced vital capacity), and FEV1/FVC ratio, with improvement ≥12% and ≥200 mL in FEV1 after bronchodilator administration confirming asthma.
• Other diagnostic tests include peak expiratory flow rate (PEFR) monitoring, bronchoprovocation testing (methacholine challenge), fractional exhaled nitric oxide (FeNO) measurement, and allergy testing to identify triggers.

Assessment Parameters

• Comprehensive assessment includes evaluation of symptom frequency, severity, and pattern; trigger identification; impact on daily activities; and medication use and adherence. The Asthma Control Test (ACT) and Asthma Control Questionnaire (ACQ) are validated tools to assess asthma control.
• Laboratory tests may include complete blood count (CBC) with differential (may show eosinophilia), arterial blood gases (ABGs) during exacerbations, and chest imaging to rule out complications or alternative diagnoses.

Controller Medications

• Inhaled Corticosteroids (ICS) are the cornerstone of asthma management, reducing airway inflammation and hyperresponsiveness. Examples include fluticasone, budesonide, and beclomethasone. These medications must be taken regularly even when asymptomatic to maintain control.
• Long-Acting Beta-2 Agonists (LABAs) like salmeterol and formoterol are used in combination with ICS for moderate to severe asthma. LABAs should never be prescribed as monotherapy due to increased risk of severe exacerbations and death.
• Other controller medications include leukotriene modifiers (montelukast, zafirlukast), long-acting muscarinic antagonists (tiotropium), and biologics (omalizumab, mepolizumab, dupilumab) for specific phenotypes.

Rescue Medications

• Short-Acting Beta-2 Agonists (SABAs) like albuterol and levalbuterol are the primary rescue medications, providing rapid bronchodilation within minutes. Frequent use (>2 times/week) indicates poor asthma control and need for adjustment of controller therapy.
• Short-acting anticholinergics (ipratropium) may be added during acute exacerbations, and systemic corticosteroids (prednisone, methylprednisolone) are used for moderate to severe exacerbations to reduce inflammation.

Stepwise Approach

• Asthma management follows a stepwise approach based on symptom control and risk assessment. Treatment is stepped up if control is inadequate and stepped down when good control is maintained for at least 3 months.
• The 2020 Global Initiative for Asthma (GINA) guidelines recommend as-needed low-dose ICS-formoterol as the preferred reliever for adults and adolescents, moving away from SABA-only treatment even for mild asthma.

Acute Exacerbation Management

1. Assess respiratory status including respiratory rate, depth, work of breathing, SpO2, and auscultate lung sounds.
2. Position patient in high Fowler's position to maximize lung expansion.
3. Administer oxygen to maintain SpO2 >92% (88-92% for those at risk for hypercapnic respiratory failure).
4. Administer SABA via nebulizer or MDI with spacer as ordered (typically 2.5-5 mg albuterol or equivalent).
5. Assist with administration of systemic corticosteroids for moderate to severe exacerbations.
6. Monitor response to therapy through vital signs, work of breathing, oxygen saturation, and peak flow measurements.
7. Prepare for possible intubation and mechanical ventilation in severe cases unresponsive to initial therapy.

Patient Education

• Educate patients on proper inhaler technique, as incorrect technique is a major cause of poor medication effectiveness. Demonstrate and have patients return-demonstrate each device they use.
• Teach patients to recognize early warning signs of exacerbation and implement their Asthma Action Plan, which should include instructions for daily management, when to increase therapy, and when to seek emergency care.
• Provide education on trigger avoidance strategies specific to identified triggers (allergens, irritants, exercise, etc.) and importance of medication adherence even when asymptomatic.

Long-term Management

• Promote self-management through education about the chronic nature of asthma, proper use of peak flow meters for monitoring, and recognition of worsening symptoms requiring intervention.
• Encourage regular follow-up appointments to assess control, adjust medications as needed, and address any barriers to adherence. Recommend annual influenza vaccination and pneumococcal vaccination as appropriate.

Asthma in Pregnancy

• Asthma affects approximately 8% of pregnant women and can worsen, improve, or remain unchanged during pregnancy. Poorly controlled asthma poses greater risks to mother and fetus than potential medication side effects.
• Most asthma medications (ICS, SABA, LABA) are considered safe during pregnancy. Budesonide has the most safety data and is preferred for pregnant women requiring an ICS.

Exercise-Induced Bronchoconstriction

• Exercise-Induced Bronchoconstriction (EIB) occurs in 80-90% of asthmatic patients and can also occur in non-asthmatics. It typically develops during or shortly after vigorous exercise and is characterized by cough, wheeze, dyspnea, and chest tightness.
• Management includes pre-treatment with SABA 15-30 minutes before exercise, proper warm-up and cool-down periods, and in some cases, daily controller medications like ICS or leukotriene modifiers.

Pediatric Considerations

• Diagnosis in children under 5 years can be challenging as spirometry is difficult to perform. Diagnosis often relies on symptom patterns, response to treatment trials, and exclusion of alternative diagnoses.
• Treatment considerations include age-appropriate delivery devices (infants/toddlers: nebulizers or MDI with mask spacers; older children: MDI with mouthpiece spacers or dry powder inhalers), growth monitoring with ICS use, and emphasis on trigger avoidance.

• Asthma is a chronic inflammatory airway disorder characterized by reversible bronchoconstriction, airway hyperresponsiveness, and mucus hypersecretion.
• Classic symptoms include wheezing, cough, and dyspnea, with symptoms often worse at night and early morning.
• Diagnosis relies primarily on demonstration of variable expiratory airflow limitation through pulmonary function tests.
• Pharmacological management follows a stepwise approach with inhaled corticosteroids as the cornerstone of controller therapy and SABAs as rescue medication.
• Nursing management includes acute exacerbation care, comprehensive patient education on medication use and trigger avoidance, and promotion of self-management.
• Special considerations include management during pregnancy, exercise-induced bronchoconstriction, and pediatric asthma.

Memory Aids

NCLEX Strategies

• For pharmacology questions, remember that controller medications (ICS, LABA, leukotriene modifiers) target inflammation and prevention, while rescue medications (SABA) provide immediate symptom relief.
• When answering prioritization questions during asthma exacerbations, focus on respiratory status assessment, oxygen administration, and bronchodilator therapy as top priorities.
• For patient education questions, emphasize the importance of proper inhaler technique, adherence to controller medications even when asymptomatic, and early recognition of worsening symptoms.
• When encountering questions about pediatric asthma, remember age-appropriate delivery devices and the challenges of diagnosis in young children.

Quick Check

Self-Assessment Checklist