Bronchial asthma is a chronic respiratory problem associated with reversible airflow obstruction. It has now become an established fact that airway inflammation plays a major role in the pathogenesis of asthma. Clinically it is characterized by episodic shortness of breath, usually accompanied by wheezing and coughing. Common precipitating factors include exposures to cold weather, upper respiratory tract infections, bad smells, exercise, ingestion of drugs like aspirin and beta-blockers…etc. The course of an acute asthmatic attack is often unpredictable. Therefore, one should never underestimate the severity of a given asthmatic attack and close monitoring and appropriate management should be employed until the patient clearly comes out of the attack. Concerning the chronic form of the disease, one should always try to classify the disease based on severity before initiating treatment. Accordingly, it is classified as intermittent or persistent asthma. The latter is again divided into mild, moderate and severe persistent asthma.
Diagnosis
- Suggestive clinical history
- Objective tests by using peak flow meters and spirometers are essential not only to make the diagnosis for certain but also to grade severity of the disease.
Treatment
Non-drug treatment
Prevention of exposure to known allergens and inhaled irritants.
Drug treatment
Drugs are required for the treatment of acute asthmatic exacerbations as well as for the treatment of chronic asthma.
TREATMENT OF ACUTE ASTHMA ATTACKS IN ADULTS:
General measures:
• Patient’s condition should be carefully monitored to assess severity, and to detect signs of improvement or deterioration. In the absence of blood gas monitoring facilities, clinical evaluation by using some important physical signs, such as the respiratory rate, pulse rate, use of accessory muscles, color, paradoxical movement of the diaphragm, speech, level of consciousness are essential.
• Humidified oxygen by mask at high concentration (6 litres/min) is important.
• Rehydrate the patient if necessary.
• Antibiotics should not be routinely given unless there is a convincing evidence for bacterial respiratory infection, such as fever, pleuritic chest pain and bronchial breath sound or chest x-ray evidence of consoldation.
Drug Treatment
I. INITIAL MANAGEMENT
First line
Salbutamol, MDI, 200 micrograms by aerosal inhalation. Could be repeated every 20 minutes for the first hour.
S/E: headache, nervousness, dizziness, palpitation, tachycardia, fine tremor, muscle cramp, paradoxical broncho-spasm.
C/I: cardiac arrythmias
Dosage forms: Oral inhalation (aerosol) preparation, 100mcg per dose; tablet, 2 mg, 4mg; syrup, 2 mg/5ml; nebulizer solution, 5 mg/5 ml, 20 ml ampoule.
OR
Aminophylline, 5mg/kg by slow i.v push over 5 minutes. The same dose could be repeated after 30 minutes.
S/E: GI disturbances, headache, irritability, nervousness, insomnia, and tremor
C/I: hypertension, ischemic heart disease, epilepsy, hyperthyroidism, congestive cardiac failure
Dosage forms: tablet, 100mg, 225mg, 350mg; injection, 250mg/10ml in 10 and 20 ml ampoule
OR
Salbutamol, 2.5-5 mg undiluted could be given via a nebulizer over 3 minutes, repeat every 20 minutes for the first one hour (For S/E, C/I and Dosage forms, see above page 114)
Alternatives
Adrenaline, 1:1000, 0.5ml sc. Repeat after ½ to 1 hour if patient doesn’t respond.
S/E: headache, nervousness, dizziness, cardiac arrythmias
C/I: cardiac arrythmias
Dosage forms: injection, 0.1% in 1 ml ampoule
II. MAINTENANCE THERAPY FOR CHRONIC ASTHMA IN ADULTS:
Requires prolonged use of anti-inflammatory drugs mainly in the form inhalers.
1.INTERMITTENT ASTHMA:
First line:
Salbutamol, inhalation -,200 microgram/puff, not more than 3 times a week (For S/E, C/I and Dosage forms, see page 114)
Alternative:
Ephedrine + Theophylline (11mg + 120mg) p.o. 100 mg, two to three times a day
S/E: GI disturbances, headache, irritability, nervousness, insomnia, tremor
C/I: hypertension, ischemic heart disease, epilepsy, hyperthyroidism, congestive cardiac failure
Dosage forms: tablet, 120 mg theophylline + 11 mg ephedrine; syrup, 0.30% theophylline + 0.24% ephedrine; elixir, 30 mg theophylline + 6 mg ephedrine per 5 ml
2. PERSISTENT MILD ASTHMA:
Refer to the nearby district Hospital
GENERAL COMMENT ON TREATMENT OF ASTHMA:
Increasing intensity: When asthma is not brought under control with current treatment even though treatment has been taken correctly; medication dose is doubled with each step.
Decreasing intensity: When the objective of treatment have been reached and maintained over some weeks; medication dose is halved at each step; the minimum treatment needed must be determined.
