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.