Breathlessness

A SILENT chest, exhaustion, normal or rising CO2, or SpO2 <92% = life-threatening → seek ICU

Cardiogenic shock (hypotension + poor perfusion), exhaustion/falling consciousness → critical care, consider CPAP/ventil

Life-threatening features (silent chest, SpO2 <92%, exhaustion, normal/rising PaCO2) → ITU/anaesthetic involvement — a n

Frequent exacerbations → optimise inhaled therapy and address the eosinophilic component

Paradoxical embolic stroke (a venous clot crossing the defect)

Haemodynamic compromise/obstructive shock, especially after trauma or in known dissection/post-MI → emergency echo + per

Exacerbation with type 2 respiratory failure (CO2 retention, acidosis) → controlled oxygen (88–92%) + consider NIV (BiPA

Eisenmenger physiology → avoid pregnancy and systemic vasodilators; refer to specialist adult congenital heart disease (

Hypoxia / respiratory failure → oxygen + escalation (cross-ref respiratory failure); VTE risk → thromboprophylaxis

Ventricular arrhythmia/syncope with low EF → ICD assessment

Acute pulmonary oedema (severe dyspnoea, pink frothy sputum, hypoxia) → sit up, oxygen, IV loop diuretic ± nitrates → cr

AIDS-defining illness (PCP, cryptococcal meningitis, cerebral toxoplasmosis, CMV retinitis) → urgent specialist treatmen

Acute exacerbation of IPF (rapid deterioration) → high mortality, specialist care

Acute severe MR from papillary muscle rupture (days after an inferior MI) → cardiogenic shock → emergency surgery

AF with systemic embolism (stroke) — anticoagulate; mitral stenosis AF needs warfarin, not a DOAC, if rheumatic/moderate

Mesothelioma (asbestos exposure + pleural effusion/chest pain/pleural thickening) → urgent investigation; it is compensa

Cardiac tamponade (shock + raised JVP + muffled sounds, pulsus paradoxus) → emergency echo-guided pericardiocentesis

Empyema (purulent fluid, pH <7.2, low glucose) → chest drain (see empyema/abscess)

TENSION pneumothorax (haemodynamic compromise, tracheal deviation) → IMMEDIATE needle/finger decompression then chest dr

Haemodynamic instability (massive PE) → consider thrombolysis; pregnancy (alters imaging choice)

Right heart failure/syncope → specialist pulmonary hypertension centre

Stridor/airway compromise, cerebral oedema (severe headache, confusion) → emergency treatment

Acute heart failure, cardiogenic shock, LV outflow obstruction or arrhythmia can complicate the acute phase

Breathing difficulty, persistent high fever, dehydration (especially infants), or features of a complication (pneumonia,

Heart failure in infancy (large VSD) → diuretics + surgical closure

Suspected PE with instability → emergency; massive PE

Ongoing pain, haemodynamic instability, arrhythmia, acute heart failure → high-risk, urgent cardiology

Respiratory acidosis (pH <7.35 with high PaCO2) → NIV; falling consciousness/exhaustion → ICU

Iron-deficiency anaemia in an adult (especially post-menopausal women / any man) → investigate for GI malignancy (urgent

Any Airway/Breathing/Circulation compromise = anaphylaxis → IM adrenaline now; biphasic reaction (recurrence hours later