Asthma is a chronic inflammatory disease of the bronchial airways
which manifests as recurrent episodes of wheeze, cough and shortness of
breath which is reversible spontaneously or with treatment. It is
characterised by increased sensitivity to many external agents. Asthma is
episodic and may be associated with seasons like the rainy season or
harmattan. Bronchial asthma occurs at all ages but peaks in childhood. It is
classified as an allergic disease, which may be due to an external or intrinsic
agent. The disease may be associated with a personal or family history of hay
fever, eczema or urticaria.
CAUSES
· Allergens e.g. house dust and animal hairs
· Drugs e.g. beta-blockers such as propranolol, prostagladin and
aspirin
F2á
Note
st nd rd Prescribing of 1 , 2 and 3 generation fluoroquinolones (e.g. ciprofloxacin and
levofloxacin) should generally be avoided in managing CAP because they are WHO
recommended second line drugs for multi-drug resistant (MDR) tuberculosis.
1-6 years; 2.5ml of 250/62 mg suspension 8 hourly;
dose doubled in severe infection
1 month-1 year; 0.25ml/kg of 125/31mg suspension
8 hourly; dose doubled in severe infection
< 1 month; 0.25 ml/kg of 125/31 mg suspension
8 hourly Or 2.5-5 ml of 400/57
suspension 12 hourly Or 1 g 12 hourly
Or
Cefuroxime, oral, (as cefuroxime axetil)
Children
> 12 years; 500 mg 12 hourly in lower respiratory-tract
infections
2-12 years, 15 mg/kg (max. 250 mg) 12 hourly
3 months-2 years, 10 mg/kg (max. 125 mg) 12 hourly
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DISORDERS OF THE RESPIRATORY SYSTEM
· Environmental e.g. air pollution, climatic changes, strong scents and
smoke
· Infections-viral or bacterial
· Exercise
· Emotions and hyperventilation (excessive deep breathing usually due
to anxiety)
· Occupational exposure to industrial chemicals, dust and drug
manufacturing
SYMPTOMS
· Episodic breathlessness
· Tightness of the chest
· Cough - often nocturnal
· Wheeze
· Nocturnal symptoms - any of the symptoms waking up the patient at
night
SIGNS
· Tachypnoea (fast breathing)
· Rhonchi/wheeze
· Use of accessory muscles of respiration
Features of a life- threatening attack are:
· Inability of patient to speak full sentences in one breath
· Rapid pulse > 110/minute (>130/minute in children 2-5 years)
· Rapid respiration > 30/minute ( > 50/minute in children 2-5 years)
· Cyanosis
· Silent chest on auscultation
· Drowsiness or confusion
· Exhaustion
· Peak Expiratory Flow Rate (PEFR) is much lower than expected, less
than 33-50 %
INVESTIGATIONS
· FBC
· Stool examination
· Chest X-ray-for the exclusion of complications such as
pneumomediastinum, pneumothorax, consolidation and other
diagnoses
· Spirometry
DISORDERS OF THE RESPIRATORY SYSTEM
TREATMENT
Treatment objectives
· To relieve symptoms
· To prevent complications and recurrence
Non-pharmacological treatment
· Avoid triggers of an acute asthmatic attack
· Avoid smoking
Pharmacological treatment
(Evidence rating: A)
MANAGEMENT OF ACUTE SEVERE ASTHMA
· Oxygen, intranasal or by mask,
In high concentration
Plus
· Salbutamol, nebulised,
Adults
2.5 -5 mg 6 hourly
Children
2.5 mg 6 hourly
Plus
· Aminophylline, IV, (slow bolus injection where patient is still distressed
after 3-4 initial doses of nebulised salbutamol)
Adults
250 mg over 20 minutes and repeat after 30 minutes if necessary
Children
3-5 mg/kg over 20 minutes as a slow bolus injection or by infusion
Plus
· Hydrocortisone, IV, (to be given simultaneously with bronchodilators)
Adults
200 mg stat then 100 mg 6 hourly until clinical improvement,
Children
6-2 years; 100 mg 8 hourly
1-5 years; 50 mg 8 hourly
<1 year; 5 mg 8 hourly
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Caution
Exercise caution when giving Aminophylline to adults who have been on Theophylline
tablets as there is a high risk of cardiac arrhythmias, seizures (due to toxic blood levels). Avoid
bolus injection; give slow infusion over 6-8 hours if needed.
!
DISORDERS OF THE RESPIRATORY SYSTEM
Plus
· Prednisolone, oral, (start as a single dose at the same time as
hydrocortisone, soon after breakfast)
Adults
30-40 mg daily
Children
> 5 years; 30-40 mg as a single daily dose for 3-5 days
2-5 years; 20 mg as a single daily dose for 3-5 days
< 2 years; 1-2 mg/kg daily as a single dose for
3-5 days
