INSTRUCTION
Examine this patient's chest.
SALIENT FEATURES
History
· Determine whether there is a reversible airway obstruction by history. Are the wheezing and breathlessness reversible?
· Tightness in the chest.
· Recurrent cough.
· Exacerbation of the cough or wheeze at night or after exercise.
· Improvement of the cough or wheeze with bronchodilator therapy.
· Fever, yellowish sputum.
· History of atopy (eczema, hay fever).
· History of rhinitis, nasal polyps.
Examination
· Bilateral scattered wheeze.
· Examine the sputum cup.
· Comment on accessory muscles of respiration, tachycardia, pulsus paradoxus and whether the patient can utter sentences
without stopping to take a breath.
DIAGNOSIS
This patient has a history of hay fever and bilateral scattered wheeze (lesion) due to bronchial asthma (aetiology), and is breathless
at rest (functional status).
QUESTIONS
Mention a few trigger factors known to aggravate asthma.
· Infection.
· Emotion.
· Exercise.
· Drugs, e.g. beta-blockers.
· External allergens.
What do you understand by the term 'asthma'?
Asthma is an inflammatory disorder characterized by hyper-responsiveness of the airway to various stimuli, resulting in widespread
narrowing of the airway. The changes are reversible, either sp~mtaneou,;ly or as a resnh of therapy
ADVANCED-LEVEL QUESTIONS
What do you understand by the term 'intrinsic asthma'?
Intrinsic asthma is of non-allergic aetiology and usually begins after the age of 30 years. It tends to be more continuous and more
severe: status asthmaticus is common in this group.
What do you understand by the term 'extrinsic asthma'?
Extrinsic asthma has a clearly defined history of allergy to a variety of inhaled factors and is characterized by a childhood onset and
seasonal variation.
What are the indications for steroids in chronic asthma?
· Sleep is disturbed by wheeze.
· Morning tightness persists until midday.
· Symptoms and peak expiratory flows progressively deteriorate each day.
· Maximum treatment with bronchodilators.
· Emergency nebulizers are needed.
What is the effect of reducing or discontinuing inhaled budesonide in patients with mild asthma?
Early treatment with inhaled budesonide results in long-lasting control of mild asthma (i.e. FEV~ more than 85% of predicted value).
Maintenance therapy can usually be given at a reduced dose, but discontinuation of treatment is often accom-panied by
exacerbation of the disease.
How would you manage a patient with acute asthma?
· Nebulized beta-agonists, e.g. terbutaline or salbutamol.
· Oxygen, using a high concentration.
· High-dose steroids: intravenous hydrocortisone or oral prednisolone or both.
· Blood gases.
· CXR to rule out pneumothorax.
When life-threatening features are present:
· Add ipratropium to nebulized beta-agonist.
· Intravenous aminophylline or salbutamol or terbutaline.
What do you know about the British Thoracic Society step care regimen for the management of chronic asthma in adults
(Thorax /997: 52: S1-24)?
· Step 1: Inhaled short-acting beta-agonists used as required for symptom relief. If required more than once, go to step 2.
· Step 2: Step I plus regular inhaled anti-inflammatory agents (such as beclomethasone, budesonide, cromoglicate or nedocromil
sodium).
· Step 3: Step I plus high-dose inhaled steroids (using a large-volume spacer) or low-dose inhaled steroids plus a long-acting
inhaled beta-agonist bronchodilator.
· Step 4: Step I plus high-dose inhaled steroids and regular bronchodilators (long-acting inhaled or oral beta-agonists,
sustained-release theophylline, inhaled ipratropium).
· Step 5: Step 4 plus addition of oral steroids.
Patients should be started on treatment at the step most appropriate to the initial severity. A rescue course of prednisolone may be
needed at any time and at any step. Stepwise reduction in treatment should be undertaken after the asthma has been stable over a
3-6-month period.
What are the features of acute severe asthma?
· Inability to complete a sentence in one breath.
· Respiration rate greater than 25 per minute.
· Pulse rate greater than 110 beats per minute.
· Peak expiratory flow rate less than 50% of predicted or best.
What are the life-threatening indicators in acute asthma?
· Peak expiratory flow rate less than 33% of predicted or best.
· Exhaustion, confusion, coma.
· Silent chest, cyanosis or feeble respiratory effort.
· Bradycardia or hypotension.
Note. Arterial blood gases should be measured if anyof these features are present or if oxygen saturation is less than 92%.
What are the indicators of a very severe, life-threatening attack?
· Normal (5-6 kPa, 36-45 mmHg) or increased carbon dioxide tension.
· Severe hypoxia of less than 8 kPa (60 mmHg).
· Low pH.
What is the value of assessing pulsus paradoxus in a patient with acute severe asthma ?
It is a poor guide to the severity of acute asthma as it compares poorly with the measurement of peak flow.
In which other conditions is wheeze a prominent sign?
Chronic obstructive airway disease, left ventricular failure (cardiac asthma), poly-arteritis nodosa, eosinophilic lung disease,
recurrent thromboembolism, tumour causing localized wheeze.
What are the indications for mechanical ventilation with intermittent positive pressure ventilation ?
· Worsening hypoxia (Pao2 <8 kPa) despite 60% inspired oxygen.
· Hypercapnia (Pace2 >6 kPa).
· Drowsiness.
· Unconsciousness.
rofessor Peter J. Barnes, contemporary chest physician, National Institute for Heart and Lung Diseases, London; his major interest
is asthma.