Asthma in Children

Intro & Pathophysiology - Wheezy Beginnings

• Definition (GINA): Chronic airway inflammation with respiratory symptoms (wheeze, SOB, chest tightness, cough) varying in time/intensity, plus variable expiratory airflow limitation.
• Prevalence: High in India (est. 5-10% of children); significant childhood morbidity.
• Core Pathophysiology (Triad):
  • Bronchoconstriction (reversible smooth muscle spasm)
  • Airway Inflammation (eosinophils, mast cells, $T_H2$ cells)
  • Airway Hyperresponsiveness (AHR) to stimuli
• Common Triggers: Viral URIs, allergens (dust mites, pollens), irritants (smoke, pollution), exercise, cold air.
  • 📌 Mnemonic (AIR): Allergens, Infections, Rritants.

⭐ Asthma is the most common chronic disease of childhood.

Signs & Diagnosis - Spotting the Puff

• Symptoms (The "Puff" Clues):
  • Recurrent cough (worse at night, with exercise/laughter)
  • Audible wheeze (high-pitched, expiratory)
  • Shortness of breath (dyspnea)
  • Chest tightness or pain
• Clinical Signs (Doctor's Observations):
  • Tachypnea, use of accessory muscles (neck, chest)
  • Intercostal/subcostal retractions
  • Auscultation: Expiratory wheeze, prolonged expiratory phase
• Key Diagnostic Tests:
  • Spirometry: FEV1/FVC ratio < 0.8 (or < 0.9 in younger children). ↓FEV1.
  • Peak Expiratory Flow Rate (PEFR): Diurnal variability >20%.
  • Bronchodilator Reversibility: Significant improvement (↑FEV1 >12% and >200ml) post-bronchodilator.
  • Fractional Exhaled Nitric Oxide (FeNO): Elevated levels suggest eosinophilic airway inflammation.
  • Allergy testing: Skin prick or specific IgE to identify triggers.

⭐ A normal chest X-ray is common in asthma; its main role is to exclude other conditions like foreign body aspiration or pneumonia.

Severity & Control - Grading the Gasp

⭐ Asthma severity is assessed before starting controller treatment to guide initial therapy, while asthma control is assessed after treatment has been ongoing for at least 4 weeks to guide adjustments.

Asthma Severity (GINA, Pre-Treatment)

Management - Breathing Easy Plan

GINA Stepwise (6-11 yrs):

Acute Exacerbation: (Assess severity: PRAM score)

• 📌 $O_2$ SIPS My Lungs:
  • Oxygen: Maintain $SpO_2$ >94%
  • Salbutamol: SABA via MDI+spacer or nebulizer, repeat doses
  • Ipratropium Bromide: Add for mod-severe exacerbations
  • Prednisolone: Oral systemic corticosteroids, 1-2 mg/kg (max 40-60mg)
  • Sulphate (Magnesium): IV $MgSO_4$ for severe/life-threatening, unresponsive to SABA
  • LTRA: +/- Leukotriene Receptor Antagonist (consider if already on it)

Non-Pharmacological:

• Trigger avoidance
• Written asthma action plan
• Inhaler technique education

⭐ Inhaled corticosteroids (ICS) are the most effective long-term control therapy for persistent asthma in children.

Special Aspects - Little Lungs Care

• Exercise-Induced Bronchoconstriction (EIB): Dx: clinical/challenge. Rx: SABA pre-exercise, LTRA, ICS.
• Viral Wheeze vs. Asthma (Preschool): Many wheeze, few develop persistent asthma.

  ⭐ In preschool children, recurrent wheezing is common, but only a subset will develop persistent asthma; risk factors include parental asthma, atopic dermatitis, and wheezing without colds.

• Allergic Bronchopulmonary Aspergillosis (ABPA): In asthmatics: worsening control, eosinophilia, ↑IgE. Rx: Steroids, antifungals.
• Immunotherapy: SCIT/SLIT for specific allergies, not routine.
• Prevention: Primary, secondary, tertiary levels.
• Comorbidities: Manage allergic rhinitis, GERD, obesity actively to improve asthma control.

High‑Yield Points - ⚡ Biggest Takeaways

• Asthma is the most common chronic disease in children, characterized by reversible bronchoconstriction.
• Diagnosis is clinical, supported by spirometry showing reversible airflow obstruction (↑FEV1 >12% post-SABA).
• Key triggers: viral infections (most common), allergens, irritants.
• Management follows a stepwise approach; inhaled corticosteroids (ICS) are the mainstay for persistent asthma.
• Acute exacerbations: O2, SABA, systemic corticosteroids.
• The "Rule of Twos" helps assess asthma control and the need to step up therapy.