Shortness of Breath

Dyspnoea is the uncomfortable awareness of one’s breathing effort.  Shortness of breath and breathlessness can be used interchangeably.


  • Respiratory diseases can cause breathlessness by
    • stimulating intrapulmonary sensory nerves (e.g. in pneumothorax, interstitial inflammation and pulmonary embolus)
    • increasing the mechanical load on respiratory muscles (e.g. in airflow obstruction or pulmonary fibrosis)
    • causing hypoxia, hypercapnia or acidosis which stimulates chemoreceptors

Acute Scenario


  • As with any acute patient, make sure to administer high flow (15l, non-rebreather) oxygen to all patients (after airway is secured)
    • Urgent treatment
      • If respiratory rate is really low (<10bpm), consider bag/mask assistance
      • For patients with wheeze, nebulised salbutamol (5mg initially) can be started
        • For known asthmatic/COPD patients, nebulised ipratropium bromide (0.5mg) may also be given in a nebuliser
      • For patients in suspected anaphylactic shock, give IM adrenaline
      • For patients with a suspected tension pneumothorax, this requires decompression
      • For patients with suspected acute coronary syndrome, consider nitrates, aspirin, morphine


  • Ask about the duration of breathlessness; its speed of onset (acute vs gradual); its progression (static vs fluctuating vs progressively worsening)
    • Any precipitating event e.g. trauma, exercise, palpitations, chest pain
    • Worse/better in any position, after taking any medication, during any time of day
    • (if uncertain about the aetiology e.g. in a patient who has transient episodes but is normal at present, ask the patient to describe the breathlessness- often ‘I can’t seem to take a deep enough breath’ is described in psychogenic causes)
  • Any associated symptoms e.g.
    • chest pain- pleuritic or constant; sharp, crushing, aching, stabbing, dull etc;
    • palpitations…
    • cough/sputum- productive of what? colour? volume? any haemoptysis (blood)?
    • any leg pain/swelling
    • fever, malaise, night sweats
  • Past medical history
    • Previous similar events
    • Asthma/COPD
    • Cardiac history
    • Allergies
    • Anxiety
    • Taking any drugs (prescribed/ over-the-counter/ illicit)
  • Family history
  • Social History
    • Ask about
      • occupation
      • smoking
      • pets
      • travel
      • alcohol
      • contact with birds
      • exercise tolerance (how much can you do normally/on a good day?)
      • home circumstances and activities of daily living


  • Full general and cardiorespiratory examination


  • CXR
  • ABGs
  • FBC, U&Es, LFTs, Clotting
  • D-Dimers
  • Pulmonary function tests

Causes of breathlessness

  • Asthma
  • COPD
  • Pulmonary Oedema secondary to Heart failure (left sided)
  • Pneumonia
  • Pneumothorax
  • Pulmonary Embolus
  • Pleural Effusion
  • Pregnancy
  • Metabolic Acidosis (e.g. DKA)
  • Aspirin Overdose
  • Renal Failure



Acute causes of severe breathlessness
Acute causes of severe breathlessness

Management of acute SOB

  • Treat every patient with an ABCDE approach
    • NB Most, if not all, acutely breathless patients should receive 15l, high flow oxygen (with the option of reducing in patients with COPD after an ABG)
    • Treat underlying cause
  • For cardiac causes (and/or other causes of pulmonary oedema)
    • Acute management is IV furosemide 40mg (or 80mg depending on patient size/severity of oedema) stat plus diamorphine 2.5/5mg plus metoclopremide 10mg
  • For most respiratory causes (NB see acute management of individual conditions for specific management)
    • Nebulised salbutamol 2.5-5mg is usually 1st line
    • Steroids are often used (usually high dose oral prednisolone e.g. 50mg)

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s