Asthma

1. Overview

Asthma is a chronic inflammatory airway disease characterised by variable respiratory symptoms and variable airflow obstruction. The typical symptoms are wheeze, shortness of breath, chest tightness and cough. Symptoms often vary over time and may be triggered by exercise, cold air, allergens, viral infections, smoke or occupational exposure.

In an OSCE, asthma may appear as a history station, acute breathlessness station, wheeze station, counselling station or chronic disease review. The key is to assess control, identify triggers, check treatment adherence and inhaler technique, and recognise acute severe or life-threatening asthma.

Key OSCE priorities

• Assess whether the patient is acutely breathless or unstable.
• Ask about wheeze, shortness of breath, chest tightness and cough.
• Ask whether symptoms vary over time.
• Ask about night-time and early-morning symptoms.
• Ask about triggers such as exercise, cold air, dust, pollen, animals, smoke and viral infections.
• Ask about reliever inhaler use and recent increase in use.
• Ask about previous hospital admission, ICU admission or ventilation.
• Assess asthma control and impact on daily life.
• Check inhaler adherence and inhaler technique.
• Measure oxygen saturation and peak flow if acute asthma is suspected and safe.

Typical asthma features

• Episodic wheeze.
• Shortness of breath.
• Chest tightness.
• Cough, especially at night or early morning.
• Symptoms triggered by exercise, allergens, cold air or infection.
• Personal history of atopy, eczema or allergic rhinitis.
• Family history of asthma or atopy.
• Improvement with bronchodilator treatment.
• Variable peak flow or spirometry results.

Red flag features

• Unable to complete sentences.
• Severe breathlessness at rest.
• Silent chest.
• Cyanosis.
• Exhaustion.
• Confusion or reduced consciousness.
• Low oxygen saturation.
• Peak flow less than 50 percent of best or predicted.
• Poor response to reliever inhaler.
• Previous ICU admission or ventilation for asthma.
• Hypotension or arrhythmia.

2. History Taking

Opening

• Wash hands.
• Introduce yourself.
• Confirm patient identity.
• Explain that you would like to ask about their breathing and asthma symptoms.
• Gain consent.
• Check whether the patient is currently very breathless, has chest pain, feels faint or is struggling to speak.
• If acutely unwell, state that you would assess using ABCDE and call for senior help.

Presenting complaint

• Ask what symptoms brought the patient in.
• Ask when the symptoms started.
• Ask whether onset was sudden or gradual.
• Ask whether symptoms are improving, worsening or persistent.
• Ask about wheeze.
• Ask about shortness of breath.
• Ask about chest tightness.
• Ask about cough.
• Ask whether symptoms are episodic or continuous.
• Ask whether this has happened before.

Asthma symptom pattern

• Ask whether symptoms vary from day to day.
• Ask whether symptoms are worse at night.
• Ask whether symptoms are worse in the early morning.
• Ask whether symptoms occur after exercise.
• Ask whether symptoms occur after exposure to dust, pollen, animals or mould.
• Ask whether cold air triggers symptoms.
• Ask whether viral infections trigger symptoms.
• Ask whether symptoms improve with reliever inhaler.

Severity assessment in acute symptoms

• Ask whether the patient can speak in full sentences.
• Ask whether they are breathless at rest.
• Ask whether they feel exhausted.
• Ask whether they feel drowsy or confused.
• Ask whether their reliever inhaler is helping.
• Ask how many puffs of reliever they have used today.
• Ask whether they have needed emergency treatment before.
• Ask whether they have ever been admitted to ICU or ventilated for asthma.

Asthma control assessment

• Ask how often they have daytime symptoms.
• Ask how often they wake at night due to asthma.
• Ask how often they use reliever inhaler.
• Ask whether asthma limits exercise, work, school or daily activities.
• Ask whether they have had recent asthma attacks.
• Ask whether they have needed oral steroids recently.
• Ask whether they have attended emergency department or been admitted recently.
• Ask whether they have a written asthma action plan.

Triggers

• Exercise.
• Cold air.
• Dust.
• Pollen.
• Animals.
• Mould.
• Smoke.
• Vaping.
• Strong smells or fumes.
• Viral infections.
• Stress or emotion.
• Occupational exposure.
• NSAIDs in sensitive patients.
• Beta-blockers.
• Reflux symptoms.

Occupational asthma screen

• Ask about job role.
• Ask about exposure to flour, wood dust, chemicals, cleaning agents, latex, animals or isocyanates.
• Ask whether symptoms improve on weekends or holidays.
• Ask whether symptoms worsen during work shifts.
• Ask whether colleagues have similar symptoms.
• Ask whether personal protective equipment is used.
• Ask when symptoms started in relation to the job.

Associated symptoms

• Fever or rigors.
• Productive cough.
• Purulent sputum.
• Pleuritic chest pain.
• Haemoptysis.
• Weight loss.
• Night sweats.
• Chest pain suggestive of cardiac disease.
• Palpitations.
• Syncope or collapse.

Alternative diagnosis screen

• Smoking history and chronic sputum suggesting COPD.
• Sudden pleuritic chest pain and breathlessness suggesting PE or pneumothorax.
• Fever and focal chest symptoms suggesting pneumonia.
• Orthopnoea and ankle swelling suggesting heart failure.
• Stridor or throat tightness suggesting upper airway obstruction.
• Voice change and inspiratory noise suggesting vocal cord dysfunction.
• Weight loss or haemoptysis suggesting malignancy or TB.

Past medical history

• Age at asthma diagnosis.
• Previous asthma attacks.
• Previous hospital admissions.
• Previous ICU admission or ventilation.
• Eczema.
• Allergic rhinitis.
• Nasal polyps.
• Food allergy or anaphylaxis.
• COPD or bronchiectasis.
• Pneumonia.
• Gastro-oesophageal reflux disease.
• Obesity.
• Anxiety or panic disorder.

Drug history and allergies

• Current reliever inhaler.
• Current preventer inhaler.
• Combination inhalers.
• Spacer use.
• Adherence to inhalers.
• Inhaler technique.
• Recent oral steroid courses.
• Previous side effects from inhaled or oral steroids.
• Beta-blocker use.
• NSAID sensitivity or aspirin-exacerbated respiratory disease.
• Antihistamines or nasal steroids for allergic rhinitis.
• Drug allergies and reaction.

Family history

• Asthma.
• Eczema.
• Allergic rhinitis.
• Food allergy.
• COPD.
• Atopy in parents or siblings.

Social history

• Smoking status and pack-year history.
• Vaping.
• Cannabis or recreational drug use.
• Home environment and damp or mould exposure.
• Pets.
• Occupation and workplace exposures.
• Exercise tolerance.
• Impact on sleep.
• Impact on work, school or daily activities.
• Ability to afford and access inhalers.
• Support at home.

Ideas, concerns and expectations

• Ask what the patient thinks is causing the symptoms.
• Ask what they are most worried about.
• Ask whether they are worried about having an asthma attack.
• Ask whether they have concerns about inhalers or steroids.
• Ask what they were hoping would happen today.
• Acknowledge that breathlessness and wheeze can be frightening.

Red flags

• Unable to speak in full sentences.
• Breathlessness at rest.
• Silent chest.
• Cyanosis.
• Exhaustion.
• Confusion or drowsiness.
• Poor response to reliever inhaler.
• Previous ICU admission or ventilation.
• Chest pain, haemoptysis or syncope.
• Low oxygen saturation.

Closing the history

• Summarise the key points back to the patient.
• Ask if they would like to add anything else.
• Thank the patient.
• State that you would check observations, oxygen saturation, peak flow if safe, and examine the respiratory system.

3. Physical Examination

Examination should assess severity first. In acute asthma, look for respiratory distress, oxygen desaturation, silent chest, exhaustion and reduced consciousness before proceeding with a routine respiratory examination.

Before starting the examination

• Wash hands or use alcohol gel.
• Introduce yourself with name and role.
• Confirm the patient's identity.
• Explain the examination clearly.
• Gain consent.
• Ask whether the patient is comfortable to proceed.
• Position the patient sitting upright.
• Expose the chest appropriately while maintaining dignity.
• Ask for a chaperone if appropriate.

Initial assessment

• Look from the end of the bed.
• Assess whether the patient is breathless, cyanosed, pale, sweaty or exhausted.
• Assess whether the patient can speak in full sentences.
• Look for tripod position.
• Look for use of accessory muscles.
• Look for intercostal or subcostal recession.
• Look for oxygen therapy, nebuliser, inhalers or spacer.
• Look for reduced respiratory effort, which is an ominous sign.
• If acutely unwell, perform ABCDE assessment and call for senior help.

ABCDE assessment if acutely unwell

• Airway: check if the patient can speak and whether the airway is patent.
• Breathing: assess respiratory rate, oxygen saturation, work of breathing, chest expansion and auscultate for wheeze or silent chest.
• Circulation: assess pulse, blood pressure, capillary refill, skin temperature and obtain IV access if needed.
• Disability: assess consciousness level and capillary blood glucose.
• Exposure: check temperature, rash, triggers and signs of infection while maintaining dignity.

Vital signs

• Respiratory rate.
• Oxygen saturation.
• Heart rate.
• Blood pressure.
• Temperature.
• Level of consciousness.
• Peak expiratory flow if safe and appropriate.
• Pain score if chest pain is present.

Hands

• Look for peripheral cyanosis.
• Check capillary refill time.
• Look for tremor from beta-agonist use.
• Look for nicotine staining.
• Look for finger clubbing, which is not typical of asthma and suggests another diagnosis.
• Look for steroid-related skin thinning or bruising if long-term steroid use.
• Assess peripheral temperature.

Pulse and blood pressure

• Assess pulse rate.
• Assess pulse rhythm.
• Tachycardia may result from hypoxia, distress or beta-agonist use.
• Arrhythmia is a life-threatening feature in acute severe asthma.
• Measure blood pressure.
• Hypotension is concerning and requires urgent escalation.

Face, mouth and neck

• Look for central cyanosis.
• Look for conjunctival pallor.
• Look for pursed-lip breathing.
• Look for nasal polyps or allergic features if relevant.
• Look for oral candidiasis from inhaled corticosteroid use.
• Assess cervical and supraclavicular lymph nodes if alternative diagnosis is suspected.
• Check tracheal position.
• Assess jugular venous pressure if cardiac disease is considered.

Chest inspection

• Inspect chest shape.
• Look for hyperinflation.
• Look for symmetrical chest movement.
• Look for scars.
• Look for chest wall deformity.
• Look for respiratory distress.
• Observe respiratory pattern.
• Look for Harrison sulci in chronic childhood asthma if relevant.

Palpation

• Assess chest expansion.
• Compare expansion on both sides.
• Chest expansion may be reduced in severe asthma due to hyperinflation.
• Palpate for chest wall tenderness.
• Assess tactile vocal fremitus if consolidation or effusion is suspected.
• Confirm tracheal position.

Percussion

• Percuss symmetrical areas of the chest.
• Hyperresonance may occur with hyperinflation.
• Dullness suggests an alternative or additional diagnosis such as pneumonia, collapse or effusion.
• Compare side to side.

Auscultation

• Auscultate symmetrical areas of the chest.
• Assess air entry.
• Listen for widespread expiratory polyphonic wheeze.
• Listen for prolonged expiratory phase.
• Listen for crackles suggesting infection or pulmonary oedema.
• Listen for focal findings suggesting pneumonia or collapse.
• A silent chest in a breathless patient is a medical emergency.

Severity findings in acute asthma

• Moderate asthma may have wheeze and breathlessness but the patient can usually speak in sentences.
• Acute severe asthma may show inability to complete sentences, high respiratory rate, tachycardia or low peak flow.
• Life-threatening asthma may show silent chest, cyanosis, poor respiratory effort, arrhythmia, hypotension, exhaustion, confusion or reduced consciousness.
• Near-fatal asthma involves raised carbon dioxide level or need for ventilation.

Cardiovascular examination

• Assess JVP if heart failure is suspected.
• Auscultate heart sounds.
• Check for murmurs.
• Look for peripheral oedema.
• Cardiac wheeze can mimic asthma.

Peripheral and systemic examination

• Check for eczema or allergic skin disease.
• Check for urticaria or swelling if allergy or anaphylaxis is suspected.
• Check calves for unilateral swelling if PE is suspected.
• Look for signs of infection such as fever or focal chest signs.
• Assess BMI if obesity contributes to breathlessness.

To complete the examination

To complete my examination, I would review observations, check oxygen saturation, measure peak expiratory flow if safe, compare it with best or predicted value, assess inhaler technique, and arrange further tests such as spirometry, bronchodilator reversibility, FeNO, chest X-ray, ECG or blood gas depending on severity and diagnostic uncertainty.

4. Differential Diagnosis

Common differentials

• COPD.
• Viral-induced wheeze.
• Acute bronchitis.
• Pneumonia.
• Bronchiectasis.
• Heart failure causing cardiac wheeze.
• Pulmonary embolism.
• Pneumothorax.
• Vocal cord dysfunction.
• Anxiety or panic attack.

Important dangerous differentials

• Anaphylaxis.
• Foreign body aspiration.
• Upper airway obstruction or stridor.
• Pulmonary embolism.
• Pneumothorax.
• Acute pulmonary oedema.
• Severe pneumonia or sepsis.

Clues against simple asthma

• Finger clubbing.
• Persistent productive cough.
• Haemoptysis.
• Weight loss.
• Fever with focal chest signs.
• Unilateral wheeze.
• Stridor.
• Chest pain with syncope.
• New onset wheeze in an older smoker.
• Poor response to bronchodilator treatment.

5. Investigations

Bedside tests

• Full observations.
• Oxygen saturation.
• Peak expiratory flow if safe and appropriate.
• Compare peak flow with personal best or predicted value.
• Capillary blood glucose if acutely unwell or receiving repeated beta-agonists.
• 12-lead ECG if chest pain, arrhythmia, severe attack or alternative diagnosis is suspected.

Objective tests for asthma diagnosis when stable

• Spirometry.
• Bronchodilator reversibility testing.
• FeNO where available.
• Peak flow variability monitoring.
• Bronchial challenge testing in selected patients if diagnosis remains uncertain.
• Allergy testing if allergic triggers are suspected.

Blood tests

• Full blood count if infection, anaemia or eosinophilia is suspected.
• CRP if infection is suspected.
• Urea and electrolytes if severe attack, dehydration or repeated nebulised therapy.
• Potassium monitoring if frequent beta-agonist treatment is used.
• Theophylline level if the patient is on theophylline and toxicity is suspected.
• Arterial or venous blood gas if severe, life-threatening asthma, hypoxia, exhaustion or poor response to treatment.

Imaging

• Chest X-ray is not needed routinely in straightforward asthma.
• Chest X-ray is indicated if pneumothorax, pneumonia, foreign body, heart failure or alternative diagnosis is suspected.
• Chest X-ray is useful if there is poor response to treatment or focal chest signs.
• CT chest is considered only if another diagnosis is suspected.

Blood gas indications

• Low oxygen saturation.
• Severe respiratory distress.
• Exhaustion.
• Confusion or reduced consciousness.
• Poor response to initial treatment.
• Suspected carbon dioxide retention.
• Life-threatening asthma features.

Important investigation points

• Asthma diagnosis should be supported by objective tests where possible.
• Normal spirometry between attacks does not completely exclude asthma.
• Peak flow helps assess acute severity and variability.
• Chest X-ray is mainly for complications or alternative diagnoses.
• A normal or raised carbon dioxide in a severe asthma attack is concerning because it may indicate respiratory fatigue.

6. Management

Management depends on whether this is acute asthma, poor chronic control or a routine asthma review. In an OSCE, always treat acute severe asthma as an emergency.

Immediate approach to acute asthma

1. Assess using ABCDE.
2. Call for senior help if severe or life-threatening features are present.
3. Sit the patient upright.
4. Give oxygen if hypoxaemic according to local oxygen target protocol.
5. Check peak expiratory flow if safe.
6. Give inhaled or nebulised short-acting bronchodilator according to local protocol.
7. Give systemic corticosteroids according to local protocol.
8. Monitor response using symptoms, respiratory rate, oxygen saturation, pulse and peak flow.
9. Escalate to senior, respiratory, anaesthetic or ICU support if poor response or life-threatening features are present.

Features requiring urgent escalation

• Silent chest.
• Cyanosis.
• Poor respiratory effort.
• Exhaustion.
• Confusion or reduced consciousness.
• Hypotension.
• Arrhythmia.
• Low oxygen saturation.
• Peak flow less than 33 percent of best or predicted.
• Rising carbon dioxide on blood gas.
• Failure to improve after initial bronchodilator therapy.

Oxygen principles

• Oxygen is given for hypoxaemia.
• Use local oxygen target saturation guidance.
• Most acutely unwell asthma patients are usually targeted to 94 to 98 percent.
• Reassess oxygen saturation after starting treatment.
• Do not delay bronchodilator and steroid treatment while arranging investigations.

Chronic asthma management principles

• Confirm the diagnosis with objective testing where possible.
• Assess symptom control and future risk of attacks.
• Check inhaler adherence.
• Check inhaler technique at every opportunity.
• Identify and reduce triggers.
• Treat comorbid allergic rhinitis, reflux or obesity where relevant.
• Provide a written personalised asthma action plan.
• Arrange follow-up after treatment changes or an acute attack.
• Step treatment up or down according to control and guideline-based therapy.

Asthma review structure

• Ask about daytime symptoms.
• Ask about night waking.
• Ask about reliever inhaler use.
• Ask about activity limitation.
• Ask about recent exacerbations.
• Ask about oral steroid courses.
• Ask about emergency attendance or admission.
• Check smoking and vaping.
• Check inhaler technique.
• Check adherence and side effects.
• Review action plan.

Inhaler technique counselling

• Ask the patient to demonstrate their inhaler technique.
• Check shaking or priming if required for the device.
• Check full exhalation before inhalation.
• Check correct seal around mouthpiece.
• Check slow deep inhalation for metered-dose inhaler.
• Check forceful deep inhalation for dry powder inhaler.
• Check breath-hold after inhalation where appropriate.
• Consider spacer for metered-dose inhaler.
• Advise rinsing mouth after inhaled corticosteroid.

Trigger control and lifestyle advice

• Stop smoking and avoid second-hand smoke.
• Avoid vaping if it worsens symptoms.
• Avoid known allergens where practical.
• Manage occupational exposure and refer if occupational asthma is suspected.
• Encourage appropriate vaccination according to local policy.
• Encourage regular physical activity when asthma is controlled.
• Manage weight if obesity contributes to symptoms.
• Treat allergic rhinitis if present.

Post-attack care

• Review why the attack happened.
• Check inhaler technique and adherence.
• Review reliever use before the attack.
• Provide or update written asthma action plan.
• Arrange early follow-up.
• Advise when to seek urgent help.
• Consider specialist referral after severe, life-threatening, recurrent or poorly controlled asthma.

When to refer

• Uncertain diagnosis.
• Poor control despite appropriate treatment and good adherence.
• Frequent exacerbations.
• Previous life-threatening asthma.
• Occupational asthma suspected.
• Atypical features such as haemoptysis, clubbing, weight loss or unilateral wheeze.
• Need for frequent oral steroids.
• Complex comorbidities or suspected severe asthma.

Safety-net advice

• Seek urgent help if reliever inhaler is not helping.
• Seek urgent help if breathlessness worsens.
• Seek urgent help if unable to speak in full sentences.
• Seek urgent help for blue lips, exhaustion, confusion or drowsiness.
• Seek urgent help for chest pain, collapse or haemoptysis.
• Follow the written asthma action plan.
• Attend follow-up after any asthma attack.

7. Examiner Questions

1. What is asthma?
2. What symptoms suggest asthma?
3. What triggers asthma symptoms?
4. What features suggest acute severe asthma?
5. What features suggest life-threatening asthma?
6. What objective tests support asthma diagnosis?
7. What is the role of peak flow?
8. When would you request a chest X-ray?
9. When would you request a blood gas?
10. What are important asthma differentials?
11. How would you manage acute asthma?
12. What should you check in an asthma review?
13. Why is inhaler technique important?
14. What is a personalised asthma action plan?
15. When would you refer to respiratory specialists?

Suggested short answers

8. OSCE Pearls

• Asthma symptoms are variable; variability is a key clue.
• Wheeze, cough, chest tightness and breathlessness are the classic symptom set.
• Night waking and frequent reliever use suggest poor control.
• Previous ICU admission is one of the most important risk factors to ask about.
• Silent chest is worse than loud wheeze.
• Check oxygen saturation and peak flow in acute asthma if safe.
• Normal examination between attacks does not exclude asthma.
• Finger clubbing is not typical of asthma and suggests another diagnosis.
• Always ask about smoking and vaping.
• Always ask about occupational triggers.
• Inhaler technique is part of management, not an optional extra.
• Poor adherence is common and should be asked about non-judgementally.
• Chest X-ray is not routine for simple asthma but is useful if complications or alternative diagnoses are suspected.
• A written asthma action plan reduces risk and improves self-management.
• Do not discharge after an attack without reviewing inhalers, technique, triggers and follow-up.

9. Example Presentation to Examiner

10. References

• NICE NG245: Asthma diagnosis, monitoring and chronic asthma management.
• BTS/NICE/SIGN Asthma Pathway.
• NICE Clinical Knowledge Summary: Asthma.
• British Thoracic Society guideline for oxygen use in adults in healthcare and emergency settings.
• Local acute asthma, oxygen therapy, respiratory and emergency medicine protocols.