What is the management and workup of Bronchial Asthma?

Management and Workup of Bronchial Asthma

Initial Diagnosis and Assessment

Establish the diagnosis through recurrent episodes of airflow obstruction with spirometry in all patients ≥5 years of age showing at least partially reversible obstruction, combined with clinical features including recurrent wheeze, persistent cough (especially nocturnal), nighttime disturbance, and symptoms triggered by viral infections, exercise, allergens, or cold air. 1, 2

Key Diagnostic Features to Identify:

• Family history of asthma or atopy 2
• Recurrent wheeze and persistent or recurrent cough 2
• Nighttime disturbance by wheeze or cough 2
• Symptoms precipitated by viral infections, exercise, excitement, allergens (feathers, pets, pollens, dust), or cigarette smoke 1, 2

Objective Measurements:

• Use spirometry to confirm airway obstruction is at least partially reversible in patients ≥5 years 1
• Obtain baseline lung function (FEV₁ or peak expiratory flow) 1
• Consider alternative causes of airway obstruction before confirming diagnosis 1

Goals of Treatment

The primary objectives prioritize complete symptom abolition, restoration of normal lung function, prevention of severe attacks, enabling normal growth in children, and minimizing school/work absences—all directly impacting morbidity and quality of life. 1

Specific targets include: 1

• Minimal (ideally no) chronic symptoms, including nocturnal symptoms
• Minimal (infrequent) exacerbations
• Minimal need for relieving bronchodilators
• No limitations on activities, including exercise
• Peak expiratory flow ≥80% of predicted or best
• Circadian variation in PEF <20%

Stepwise Pharmacologic Management

Step 1: Mild Intermittent Asthma

• Short-acting inhaled beta₂-agonist as needed for symptom relief 1
• However, the most recent evidence suggests considering ICS-LABA as needed rather than SABA alone to address underlying inflammation even at this stage 1

Step 2: Mild Persistent Asthma

Inhaled corticosteroids are the most effective anti-inflammatory medication available and form the foundation of controller therapy—they are necessary to prevent exacerbations and chronic symptoms in all patients with persistent asthma. 1, 3

• Daily low-dose inhaled corticosteroids (preferred) 1, 3
• Alternative options: cromolyn, nedocromil, or sustained-release theophylline (serum concentration 5-15 mcg/mL), though these have not been demonstrated to be as effective as inhaled corticosteroids 1
• Short-acting inhaled beta₂-agonist as needed 1

Step 3: Moderate Persistent Asthma

• Medium-dose inhaled corticosteroids PLUS long-acting beta₂-agonist 1, 4
• Short-acting inhaled beta₂-agonist as needed 1

Step 4: Severe Persistent Asthma

• High-dose inhaled corticosteroids PLUS long-acting beta₂-agonist 1, 4
• Consider adding sustained-release theophylline 4
• If symptoms remain uncontrolled, add minimal dose of oral prednisolone, preferably on alternate days 4
• Short-acting inhaled beta₂-agonist as needed; oral steroids may be required for exacerbations 1

Critical Principle: Step Up and Step Down

Therapy should be stepped up as necessary when control is inadequate and stepped down when possible to identify the least amount of medication required to achieve treatment goals. 1

Monitoring Beta₂-Agonist Use

If the patient is using more than one canister of short-acting beta₂-agonist per month, daily long-term control therapy should be increased immediately. 1

This overuse indicates:

• Inadequate anti-inflammatory control 1
• Increased risk of severe exacerbations 1, 3
• Potential for asthma-related mortality due to overreliance on bronchodilators 1, 3

Management of Acute Exacerbations

Recognition of Severe Acute Asthma (Adults):

• Too breathless to talk 1
• Respirations >25 breaths/min 1
• Pulse >110 beats/min 1
• Peak expiratory flow <50% predicted or best 1

Life-Threatening Features:

• Peak expiratory flow <33% predicted or best 1, 2
• Silent chest, cyanosis, or poor respiratory effort 1, 2
• Exhaustion, confusion, or reduced level of consciousness 1, 2
• Oxygen saturation <92% 1

Immediate Treatment Protocol:

1. High-flow oxygen 40-60% (CO₂ retention is not aggravated by oxygen therapy in asthma) 1
2. Salbutamol 5 mg or terbutaline 10 mg via oxygen-driven nebulizer 1
3. Prednisolone 30-60 mg orally OR intravenous hydrocortisone 200 mg immediately 1
4. If life-threatening features present: add ipratropium 0.5 mg nebulized 1
5. Consider intravenous aminophylline 250 mg over 20 minutes or magnesium sulfate for severe exacerbations unresponsive to initial treatment 1

Rescue Courses of Oral Steroids

Indications for initiating rescue steroids: 1

• Symptoms and PEF progressively worsen day by day
• PEF falls below 60% of patient's best
• Sleep disturbed by asthma
• Morning symptoms persist until midday
• Diminishing response to inhaled bronchodilators

Dosing: Give prednisolone 30-60 mg immediately in adults (1-2 mg/kg in children), continue each morning until two days after control is established, then stop without tapering in short courses 1

Pediatric-Specific Considerations

Children Under 2 Years:

• Diagnosis relies almost entirely on symptom patterns rather than objective testing 1, 2
• Recurrent wheeze often associated with viral infections 1, 2
• Bronchodilator response variable in first year but should still be tried 1
• Consider alternative diagnoses: gastroesophageal reflux, cystic fibrosis, chronic lung disease of prematurity 1

Children 4-11 Years:

• One inhalation of fluticasone/salmeterol 100/50 twice daily for persistent asthma 5
• Use age-appropriate delivery devices: MDI with spacer and face mask for ages 0-4 years; MDI with spacer or dry powder inhaler for ages 5+ years 2

Growth Monitoring:

Short-term reductions in growth rate occur only at inhaled steroid doses >400 µg/day, and asthma itself delays growth and puberty, but catch-up growth typically occurs—the benefits of controlled asthma outweigh minimal growth effects. 1, 3

Patient Education and Self-Management

Written Asthma Action Plan (Mandatory)

Develop a written asthma action plan in partnership with every patient, specifying daily management and instructions for managing worsening asthma. 1

The plan must include: 1

• Daily long-term control medication regimen
• How to recognize worsening asthma (symptoms and PEF thresholds)
• When to increase inhaled steroids
• When to self-administer oral steroids (typically when PEF falls below 60% of best or agreed individual threshold)
• When to seek urgent medical attention

Essential Education Components:

• Difference between "relievers" (bronchodilators) and "preventers" (anti-inflammatory medications) 1, 3
• Proper inhaler technique with demonstration and verification 1, 2
• Peak flow monitoring technique (particularly helpful for patients with difficulty perceiving symptoms or history of severe exacerbations) 1
• Environmental trigger avoidance strategies 1

For children, provide copies of the action plan to each caregiver and to the child's school. 1

Environmental Control Measures

Determine specific exposures through history of symptoms in presence of triggers, and use skin or in vitro testing to assess sensitivity to perennial indoor allergens in patients with persistent asthma. 1

Priority interventions: 1, 2

• Eliminate tobacco smoke exposure (maternal smoking is one of the most important modifiable factors)
• Reduce exposure to identified allergens (dust mites, pet dander, mold, pollens)
• Avoid irritants (cold air, strong odors, air pollution)

Follow-Up and Monitoring Schedule

Schedule follow-up visits at 1-6 week intervals while gaining control, then at 1-6 month intervals depending on step of care once sufficient control is maintained. 1

At Every Visit Assess:

• Asthma control using both impairment and risk domains 1
• Medication technique (observe actual inhaler use) 1, 4
• Written asthma action plan understanding 1
• Patient adherence and concerns 1
• Days off school/work from asthma 2
• Frequency of daytime and nighttime symptoms 2
• Frequency of relief medication use 2
• Activity limitations 2

Obtain spirometry at least every 1-2 years, more frequently for not well-controlled asthma. 1

Critical Pitfalls to Avoid

What NOT to Do:

• Do not use antibiotics for uncomplicated asthma—they have no place in management 1, 2
• Do not use antihistamines including ketotifen—they have proved disappointing in clinical practice 1, 2
• Do not use hyposensitization (immunotherapy) for asthma management 1, 2
• Do not use sedation during acute exacerbations—it is contraindicated 1
• Do not use percussive physiotherapy during acute attacks—it is unnecessary 1
• Do not combine Wixela Inhub (or similar ICS-LABA products) with additional LABA-containing medications due to overdose risk 5
• Do not use LABA monotherapy without inhaled corticosteroids—this increases risk of serious asthma-related events 5

Important Warnings:

• Doubling the dose of inhaled corticosteroids for home management of worsening symptoms is not effective—use oral corticosteroids instead 1
• When transferring patients from systemic corticosteroids to inhaled therapy, taper oral steroids slowly (reduce prednisone by 2.5 mg weekly) and monitor for adrenal insufficiency 5
• Strong CYP3A4 inhibitors (ritonavir, ketoconazole, itraconazole, clarithromycin) should not be used with ICS-LABA combinations due to increased systemic corticosteroid effects and cardiovascular adverse effects 5

Special Populations

Exercise-Induced Bronchoconstriction:

Use cromolyn, short- or long-acting beta₂-agonists, or leukotriene antagonists before exercise 4

Seasonal Asthma:

Start maintenance treatment according to assessed severity 2 weeks before season begins and continue throughout; reassess after discontinuing treatment 4

Pregnant Women:

Refer to specialist if asthma worsening during pregnancy 1

Patients Requiring Specialist Referral:

• Doubt about diagnosis 1
• Catastrophic, sudden, severe (brittle) asthma 1
• Continuing symptoms despite high-dose inhaled steroids 1
• Recent hospital discharge 1
• Asthma interfering with lifestyle despite treatment changes 1