Key Facts

Haemoptysis is the expectoration of blood from the lower respiratory tract (below the larynx). It ranges in severity from blood-streaked sputum to massive life-threatening haemoptysis. Even minor haemoptysis requires investigation to exclude serious underlying pathology.

Epidemiology

Haemoptysis accounts for approximately 10-15% of respiratory outpatient referrals. In the UK, bronchiectasis and lung cancer are the commonest identified causes. Massive haemoptysis accounts for <5% of cases but carries mortality of 50-80% if untreated. TB remains an important cause globally and in high-risk UK populations.

Aetiology

• Airway disease: bronchiectasis (commonest), bronchitis, lung cancer, carcinoid tumour
• Parenchymal: pneumonia, TB, lung abscess, aspergilloma, pulmonary vasculitis
• Vascular: PE with infarction, pulmonary AVM, mitral stenosis, DAH
• Other: coagulopathy, anticoagulant therapy, foreign body, trauma
• Cryptogenic: no cause identified in 15-30% despite full investigation

Pathophysiology

Most haemoptysis originates from the bronchial arterial circulation (90%), which operates at systemic pressure. Bronchial arteries hypertrophy in chronic inflammatory conditions (bronchiectasis, TB) creating fragile neovascular networks prone to rupture. Pulmonary arterial bleeding (5%) occurs in conditions like Rasmussen aneurysm (TB) or pulmonary AVM. Non-vascular sources include airway mucosal inflammation or tumour erosion.

Mild Haemoptysis

• Blood-streaked sputum or small-volume frank blood
• Often self-limiting
• May be associated with cough, infection, or anticoagulation

Moderate Haemoptysis

• Recurrent episodes of frank haemoptysis (20-240 ml/24h)
• Associated symptoms guide aetiology (weight loss, night sweats, chronic productive cough)

Massive Haemoptysis

• 240 ml/24 hours (or >100 ml in some definitions)

• Haemodynamic compromise, respiratory distress
• Blood-filled airway causing asphyxiation (the main cause of death — not exsanguination)

Red Flags

• Volume >100 ml in 24 hours
• Haemodynamic instability (tachycardia, hypotension)
• Respiratory distress (SpO₂ falling, tachypnoea)
• Smoker >40 years with new/persistent haemoptysis (lung cancer)
• Weight loss, night sweats (malignancy, TB)
• Known bronchiectasis or previous TB (high risk of recurrent/massive haemoptysis)

Bedside

• ABG: hypoxaemia assessment
• SpO₂ monitoring: continuous
• Sputum collection: cytology, AFB, culture
• Confirm haemoptysis (vs haematemesis or epistaxis): pH of blood (alkaline in haemoptysis), clinical context

Bloods

• FBC: anaemia (chronic/acute blood loss), thrombocytopaenia
• Coagulation screen (PT/APTT/INR): coagulopathy, anticoagulant therapy
• Group and save/crossmatch: if significant haemoptysis
• U&Es, LFTs: baseline
• CRP: infection/inflammation
• ANCA, anti-GBM: if vasculitis/DAH suspected
• D-dimer: if PE suspected (only if low pre-test probability)

Imaging

• CXR: first-line — may show mass, consolidation, cavity, effusion
• CT thorax with contrast (CTA): identifies cause in >80%; localises bleeding; may show bronchial artery hypertrophy for embolisation planning
• CTPA: if PE suspected

Special Tests

• Bronchoscopy: localise bleeding site, take biopsies/brushings, therapeutic intervention (cold saline lavage, adrenaline, balloon tamponade)
• Bronchial artery angiography: pre-embolisation assessment
• Sputum AFB/TB culture: if TB suspected
• Sputum cytology: malignant cells

Non-pharmacological

• Position: lie patient on the side of the bleeding lung (if known) to protect the unaffected lung
• Oxygen: high-flow to maintain SpO₂ >94%
• IV access: two large-bore cannulae
• NBM: in case of bronchoscopy/surgery
• Call for help early: involve respiratory team, interventional radiology, thoracic surgery

Pharmacological

• Resuscitation: IV fluids, blood products (crossmatched blood, FFP, platelets as needed)
• Reverse anticoagulation: vitamin K 5-10 mg IV (warfarin), idarucizumab (dabigatran), andexanet alfa (factor Xa inhibitors), prothrombin complex concentrate
• Tranexamic acid: 1 g IV TDS (or 500 mg nebulised TDS) — increasingly used, evidence base growing
• IV terlipressin: 1-2 mg IV (occasionally used for variceal-like massive haemoptysis)
• Treat underlying cause: antibiotics (infection), anti-TB therapy, anticoagulation for PE

Surgical/Interventional

• Bronchoscopy: diagnostic and therapeutic — cold saline lavage, topical adrenaline (1:10,000), balloon tamponade, endobronchial blocker
• Bronchial artery embolisation (BAE): first-line for massive/recurrent haemoptysis; success rate 70-90% immediately; recurrence 10-30% at 1 year
• Surgery (lobectomy/pneumonectomy): if BAE fails or recurrent massive haemoptysis; high mortality in emergency setting (~20%)
• Double-lumen ET tube: if intubated, allows isolation of bleeding lung

Referral Criteria

• 2-week wait cancer referral: unexplained haemoptysis in adults ≥40 years (NICE NG12)
• Urgent respiratory referral for recurrent or unexplained haemoptysis
• Emergency: massive haemoptysis — ICU, interventional radiology, thoracic surgery

Mild haemoptysis has a good prognosis when the underlying cause is identified and treated. Massive haemoptysis carries 50-80% mortality if untreated. BAE controls immediate bleeding in 70-90% of cases but recurrence is 10-30% at 1 year. Cryptogenic haemoptysis (no cause found) has a good prognosis — malignancy risk at 3 years is <5% if CT and bronchoscopy are normal. Lung cancer presenting with haemoptysis typically indicates advanced disease with 5-year survival <15%.

Massive Haemoptysis Emergency Algorithm

Common Causes by CXR Appearance