Asthma: Overview and Treatment
Asthma: Overview and Treatment
Asthma is a heterogeneous chronic disease characterized by chronic airway inflammation. People with asthma often have a history of respiratory symptoms such as coughing, which varies in frequency and severity, and reversible airflow limitation.
# Causes of Asthma
Factors that can trigger an asthma attack include:
- Upper respiratory tract infections: Such as Rhinovirus.
- Inhaled allergens: Including pollen, dust, pet dander.
- Exercise-induced asthma: Occurs after exercising.
- Cigarette smoke: Both direct and secondhand smoke can trigger asthma.
- Environmental pollution: Vehicle exhaust, dust.
- Weather changes: Sudden changes in temperature.
- Psychological factors: Stress, anxiety.
# Basic features of asthma
Asthma is characterized by:
- Inflammation: Chronic airway inflammation.
- Obstruction: Airflow limitation due to airway edema and smooth muscle contraction.
- Hypersensitivity: The airway is easily irritated by allergens.
# Asthma attack
An asthma attack can occur even if the patient is receiving preventive medication. They commonly occur at midnight, early morning or after exertion.
Characteristics of an asthma attack:
- Resolution: Asthma attacks usually resolve gradually due to:
- Spontaneous resolution: Body’s self-recovery.
- Sudden resolution: After using bronchodilator medication.
- Due to using bronchodilator and corticosteroid: Best treatment outcome.
# Clinical Manifestations
Shortness of breath:
- Characteristic: Difficulty breathing out, prolonged exhalation.
Lung examination:
- During an asthma attack: Lung percussion is louder than normal, wheezing, rales, rhonchi, prolonged forceful exhalation.
- Outside an asthma attack: Lungs are near normal.
Asthma in children:
- Children under 2 years old: Rapid breathing, wheezing.
Severe asthma:
- Characteristics: Lasts for more than 3 days, unresponsive to treatment, severe shortness of breath.
# Tests
- Chest X-ray:
- Early stage: Normal.
- Later stage: Emphysema, widened chest cavity, air trapping.
- Complete blood count: Increased eosinophils, elevated IgE.
# Diagnosis
- Children over 5 years old:
- History of respiratory symptoms: Coughing, wheezing, shortness of breath, chest tightness.
- Evidence of reversible airflow limitation (FEV1 < 80%).
- Positive salbutamol test: FEV1 increases by 12% after using a bronchodilator.
# Differential diagnosis
- Children under 24 months: Asthma can be confused with bronchiolitis.
# Treatment
Dosage:
- Salbutamol test dosage for bronchodilator recovery: 200 mcg.
- Salbutamol nebulizer dosage for relieving asthma attack: 0.15 mg/kg/day.
- Oral prednisolone dosage for moderate asthma attack: 1-2 mg/kg/day.
- Methylprednisolone intravenous dosage for severe asthma attack: 2 mg/kg/day.
Medication:
- Relieving asthma attack:
- Beta 2 adrenergic bronchodilator: Most commonly used medication.
- Intravenous aminophylline.
- Subcutaneous adrenaline.
- Oral or intravenous corticosteroid.
- Prevention:
- ICS (inhaled corticosteroids): Most commonly used medication.
- Leukotriene inhibitors.
# Asthma attack severity classification
Asthma attack severity is determined based on:
- Peak expiratory flow rate (PEFR):
- Moderate asthma attack: 60-80%.
- Blood gas + spirometry: Most accurate diagnosis.
- Clinical:
- Grade 1 (mild, intermittent): Symptoms < 1 time/week during the day, <= 2 times/month at night, FEV1 > 80%, PEP variation < 20%.
- Grade 2 (mild persistent): Symptoms > 1 time/week < 1 time/day during the day, > 2 times/month at night, FEV1 > 80%, PEP variation 20-30%.
- Grade 3 (moderate, persistent): Symptoms: daily during the day, > 1 time/week at night, FEV1 60-80%, PEP variation > 30%.
- Grade 4 (severe asthma): Symptoms: often, continuously during the day, often at night, FEV1 < 60%, PEP > 30%.
# Notes
- Asthma patients need to be monitored and treated according to the doctor’s instructions.
- Avoid contact with asthma triggers.
- Use medication at the correct dosage and duration.
- Be aware of any unusual symptoms and go to the hospital immediately when necessary.
Leave a Reply