Breathlessness Assessment: FY Guide

A practical Foundation doctor guide to assessing acute breathlessness on the ward, including:

• ABCDE
• focused history
• blood gases
• CXR
• ECG
• PE assessment and escalation

Breathlessness on the Ward: What Should You Do?

It is 1 am and the nurse bleeps you: “Doctor, can you review this patient? They are suddenly much more breathless.”

Breathlessness is a symptom, not a diagnosis.

It may represent a relatively straightforward exacerbation of known respiratory disease, but it can also be the first sign of pulmonary embolism, pulmonary oedema, pneumothorax, anaphylaxis, acute coronary syndrome or impending respiratory failure.

The first rule: Do not start by asking “Is this asthma or pneumonia?” Start by asking “How sick is this patient, and is there an immediately reversible or life-threatening cause?”

1. Go to the patient and get the timeline

Before opening several days of notes, establish the essentials:

• How long have they been breathless?
• Was the onset sudden or gradual?
• Is this new, or a deterioration from their baseline?
• Are they febrile?
• Is there cough or sputum, and is it clear, yellow-green, frothy or blood-stained?
• Is there chest pain — cardiac, pleuritic or associated with palpitations?
• Are there pulmonary embolism risk factors such as recent surgery or immobility?
• Are there heart-failure symptoms such as oedema, orthopnoea or paroxysmal nocturnal dyspnoea?
• What are the current observations, oxygen requirement and NEWS2?

The timing matters. Sudden breathlessness should make you think particularly about pulmonary embolism, pneumothorax, acute pulmonary oedema, anaphylaxis or arrhythmia, while a more gradual history may fit infection, COPD, heart failure or another evolving process.

2. Use the past history to narrow the field

Useful background questions include:

• Asthma — previous ICU admission or a history of brittle/severe disease?
• COPD — recent exacerbations or previous need for non-invasive ventilation?
• Other lung disease — interstitial lung disease or malignancy?
• Previous anaphylaxis?
• Cardiac disease — IHD, previous MI or heart failure?
• Previous DVT/PE, cancer or other VTE risk factors?

Review the drug chart and regular treatment:

• inhalers and nebulisers
• long-term oxygen therapy
• GTN or relevant cardiac medication
• VTE prophylaxis or anticoagulation
• allergies and recently started medicines

Also establish smoking status and the patient's usual exercise tolerance — the change from baseline is often more useful than a generic “short of breath”.

3. If the patient is unwell, assess ABCDE immediately

• A — Airway — Confirm the airway is patent. Look and listen for stridor and check for facial or tongue swelling. These findings can move anaphylaxis or upper-airway obstruction rapidly to the top of the differential.
• B — Breathing — Check respiratory rate, SpO₂, current oxygen device/FiO₂ and work of breathing. Assess tracheal position, chest expansion and air entry. Listen for wheeze, crackles, bronchial breathing or a silent chest. Percuss if pneumothorax or effusion is possible. Note sputum character, including frothy sputum or haemoptysis.
• C — Circulation — Check heart rate, blood pressure, capillary refill and fluid balance. Examine the JVP, heart sounds, calves and peripheries. Unilateral leg swelling may support DVT/PE; bilateral or sacral oedema and a raised JVP may support fluid overload or heart failure.
• D — Disability — Check temperature, GCS and capillary blood glucose. Consider whether reduced conscious level could reflect hypoxia, hypercapnia or another systemic problem.
• E — Exposure — Look for rash or urticaria, petechiae, evidence of recent procedures/trauma, and abdominal distension or tenderness where the presentation is not fitting a purely respiratory cause.

Foundation doctor tip: A patient who is becoming exhausted, confused, drowsy, cyanosed, hypotensive, has a silent chest or has rapidly increasing oxygen needs is not a routine breathlessness review. Escalate while you continue ABCDE.

4. Oxygen: treat hypoxaemia, not the sensation of breathlessness

Oxygen should be treated as a drug and prescribed to an appropriate target range.

For most acutely unwell adults the usual target is 94–98%; patients at risk of hypercapnic respiratory failure generally require a lower target such as 88–92%, with blood-gas assessment guiding further management. BNF: Oxygen

Do not let a satisfactory saturation on supplemental oxygen falsely reassure you. The patient may still be deteriorating if the oxygen requirement is rising, the respiratory rate is worsening or carbon dioxide is accumulating.

The important trend: A saturation of 94% on progressively increasing oxygen is deterioration, not reassurance.

5. Do they need a blood gas?

A blood gas is particularly useful when the patient is significantly unwell, hypoxic despite oxygen, drowsy, at risk of hypercapnic respiratory failure, or when you need to assess ventilation, acid–base status or lactate.

Read it systematically:

• pH
• PaO₂
• PaCO₂
• HCO₃⁻ / base excess
• Lactate
• Haemoglobin, electrolytes and glucose where available on the analyser

For an acute COPD exacerbation requiring hospital assessment, NICE recommends arterial blood gases with the inspired oxygen concentration recorded.

A rising PaCO₂ with acidosis or failure to improve despite treatment needs senior review and may require ventilatory support. NICE NG115: COPD diagnosis and management

6. Investigations: choose tests that answer your differential

Investigation	What it can help answer
Bloods	FBC, U&Es and CRP are common starting tests. Add troponin if chest pain/ACS is part of the differential. D-dimer should be used only within an appropriate PE probability pathway.
Blood gas	Ventilation, oxygenation, acid–base status and lactate in a clinically significant respiratory deterioration.
Chest X-ray	Consolidation, pleural effusion, collapse, pneumothorax, pulmonary oedema pattern or a mass.
ECG	Rate, rhythm, arrhythmia, ischaemia and clues to right-heart strain. ECG findings can support a differential but do not diagnose or exclude PE.
Microbiology	Blood cultures, sputum culture or other microbiology when infection is clinically suspected and the result is likely to affect management.
PEFR	Useful in suspected acute asthma when the patient is able to perform it; compare with predicted/personal best as appropriate.
CTPA	For suspected PE according to the structured clinical-probability pathway; discuss/escalate appropriately if the patient is unstable or the imaging decision is complex.

7. Do not reflexively order a D-dimer

If pulmonary embolism is a realistic possibility, use a structured clinical-probability approach rather than adding a D-dimer to every breathlessness work-up.

NICE uses the 2-level PE Wells score. A score of 4 or less is “PE unlikely” and leads to D-dimer testing; a score above 4 is “PE likely” and leads towards imaging rather than using D-dimer to rule PE out. NICE NG158: suspected pulmonary embolism

Foundation doctor tip: Breathlessness can be the only obvious feature of PE. A relatively quiet chest examination does not exclude it.

8. Build a dangerous-first differential

Diagnosis	Bedside clues
Acute asthma	Wheeze, increased work of breathing, reduced air entry; a silent chest or exhaustion is a red flag.
COPD exacerbation	Worsening breathlessness with cough/sputum change, wheeze and possible hypercapnic respiratory failure.
Pneumonia	Fever, cough, sputum, pleuritic pain, focal crackles or bronchial breathing, consolidation on CXR.
ACS	Breathlessness may accompany or occasionally dominate an ischaemic presentation, especially with chest discomfort, sweating or ECG change.
Pulmonary embolism	Sudden dyspnoea, pleuritic chest pain, haemoptysis, tachycardia, syncope, hypoxia or VTE risk factors.
Heart failure / pulmonary oedema	Orthopnoea, PND, oedema, raised JVP, crackles and frothy sputum.
Pneumothorax	Sudden breathlessness, pleuritic pain, unilateral reduced air entry or hyperresonance; haemodynamic compromise raises concern for tension physiology.
Anaphylaxis	Acute breathlessness with stridor/wheeze, facial or tongue swelling, urticaria and/or circulatory compromise.

Also keep lung malignancy and acute abdomen / non-respiratory causes on the secondary list when the timeline is more subacute or the chest examination does not fit.

9. Match bedside clues to the differential

• Stridor or facial/tongue swelling → think upper-airway obstruction/anaphylaxis.
• Silent chest or markedly reduced air entry in asthma → severe deterioration.
• Unilateral reduced air entry with sudden onset → think pneumothorax.
• Crackles + raised JVP + peripheral oedema + orthopnoea/PND → think heart failure/pulmonary oedema.
• Fever + purulent sputum + focal chest signs → think infection/pneumonia.
• Sudden dyspnoea + pleuritic pain/haemoptysis + VTE risk → think PE.
• Chest discomfort + ECG ischaemia/troponin pathway → consider ACS.
• Drowsiness + low respiratory rate or rising CO₂ → think ventilatory failure and medication/neurological causes as well as lung disease.

10. Treat the cause, then reassess

Oxygen, nebulisers or fluids can temporarily improve numbers without solving the diagnosis.

After each intervention, repeat the clinical assessment:

• respiratory rate
• SpO₂ and oxygen requirement
• work of breathing
• heart rate and blood pressure
• GCS
• chest examination
• blood-gas trend when indicated
• response to treatment

11. When should you escalate?

Escalate urgently if:

• Airway compromise, stridor or significant facial/tongue swelling
• Severe respiratory distress or rapidly increasing work of breathing
• A silent chest or markedly reduced air entry
• Persistent hypoxaemia or rapidly increasing oxygen requirement
• Drowsiness, confusion or falling GCS
• Hypercapnia with acidosis or worsening blood-gas parameters
• Hypotension, shock, syncope or significant arrhythmia
• Suspected tension pneumothorax, major PE, anaphylaxis or acute pulmonary oedema
• The patient is not improving despite initial treatment
• You cannot explain the deterioration
• You are worried

You do not need a final diagnosis before calling.

A useful escalation might be: “This patient has developed acute breathlessness over 30 minutes.

They are tachypnoeic with a new oxygen requirement, have unilateral reduced air entry on the right and pleuritic chest pain.

I am concerned about a pneumothorax and need you to review them now.”

A practical Foundation doctor example

You are called to a patient who has become suddenly breathless after several days of reduced mobility. They have pleuritic chest pain, tachycardia and a relatively unremarkable chest examination.

• Start with ABCDE and assess physiological stability.
• Check oxygenation and give oxygen only if indicated to the correct target range.
• Take a focused history including recent surgery/immobility, previous VTE, cancer and haemoptysis.
• Obtain ECG and appropriate baseline investigations.
• Use the 2-level PE Wells pathway rather than ordering a D-dimer reflexively.
• If PE is clinically likely, escalate and follow the imaging/treatment pathway rather than waiting for an unnecessary D-dimer.
• Reassess continuously if the patient becomes hypotensive, more hypoxic or clinically unstable.

The Foundation doctor breathlessness rule

GO NOW → ABCDE → OXYGEN TARGET → FOCUSED HISTORY → CHEST + CIRCULATION EXAM → GAS IF NEEDED → TARGETED TESTS → DANGEROUS DIFFERENTIAL → TREAT → REASSESS → ESCALATE

The key message

Breathlessness is not a diagnosis. Stabilise first, then use the timeline, examination and targeted investigations to separate airway disease, infection, fluid, clot, collapse and non-respiratory causes.

Educational note: This article is intended as an educational guide for Foundation doctors. For individual patients, follow current NICE/BNF guidance and your NHS organisation’s deteriorating-patient and emergency-care pathways, and seek senior advice when appropriate.