Life-Threatening Haemoptysis

Life threatening haemoptysis is expectoration of blood that threatens life by asphyxia, haemodynamic collapse or both. Volume thresholds vary (200 to 600 mL in 24 hours), but any volume that impairs gas exchange or airway patency counts, since death is usually from asphyxia and not from blood loss.

Epidemiology. Massive haemoptysis is under 5% of all haemoptysis. Mortality is high without control of bleeding.

Causes and associations.

• Bronchiectasis (including cystic fibrosis) and tuberculosis (active disease, or post-tuberculous cavities and aspergilloma).
• Lung cancer, necrotising pneumonia and lung abscess.
• Vasculitis (granulomatosis with polyangiitis, anti-GBM disease) and diffuse alveolar haemorrhage.
• Pulmonary arteriovenous malformation, pulmonary artery aneurysm (Rasmussen, Hughes-Stovin), pulmonary embolism and mitral stenosis.
• Anticoagulant or antiplatelet use, coagulopathy, trauma and iatrogenic injury (biopsy, pulmonary artery catheter).

Pathophysiology. Over 90% of bleeding comes from the bronchial arteries, which are at systemic pressure and hypertrophy in chronic inflammation. Pulmonary artery bleeding is less common but is more often fatal.

Presentation is bright red frothy blood, cough, dyspnoea, hypoxia, and sometimes shock. Side of bleeding may be indicated by chest pain, crackles or the patient's own sense. Look for features of the cause: fever, weight loss, clubbing, haematuria (vasculitis) and cardiac murmur.

Red flags.

• Bleeding over 100 mL in 24 hours, or hypoxia and respiratory distress.
• Shock or falling haemoglobin.
• Anticoagulation, bleeding disorder or known aneurysm.

Do not delay resuscitation. Obtain full blood count, coagulation tests, group and crossmatch, renal function, urinalysis, arterial gas and chest radiograph. Multidetector CT with angiography of the chest locates the bleeding side and source, identifies bronchial or non-bronchial systemic arteries and the cause, and directs embolisation. Bronchoscopy lateralises the bleeding and clears clots, and a rigid scope is preferred when bleeding is brisk.

Send sputum for mycobacteria and nucleic acid amplification testing for tuberculosis, and for fungal culture. Autoantibody tests where vasculitis is possible.

Differential diagnosis. Haematemesis, nasopharyngeal bleeding and pseudohaemoptysis (Serratia marcescens colonisation).

Position and airway. Place the patient with the bleeding side down. Give high flow oxygen. Intubate early for hypoxia, exhaustion or ongoing bleeding with a large tube (8.0 mm or more). For unilateral bleeding, isolate the lung with selective intubation of the other main bronchus, a bronchial blocker or a double lumen tube.

Resuscitation. Two large bore cannulae, blood products for shock, and correction of coagulopathy. Reverse anticoagulants: vitamin K antagonist with prothrombin complex concentrate 25 to 50 units/kg and vitamin K 5 to 10 mg IV, and direct oral anticoagulants with the specific reversal agent or prothrombin complex concentrate.

Tranexamic acid. 1 g IV over 10 minutes, then 1 g every 8 hours. Nebulised tranexamic acid 500 mg (5 mL of 100 mg/mL) three times daily is an alternative. Reduce IV doses in renal impairment. Avoid with active thrombosis.

Cough suppression. Cautious codeine 15 to 30 mg orally every 4 to 6 hours for mild cases only, since sedation risks the airway.

Definitive haemostasis.

• Bronchial artery embolisation controls bleeding in most cases, with a recurrence rate of about 10 to 25%. Rare risk is spinal cord ischaemia.
• Bronchoscopic measures: cold saline lavage (4 °C, 50 mL aliquots), topical adrenaline 1 in 10,000 (2 to 5 mL), balloon tamponade, and endobronchial blockers.
• Surgical resection for localised disease with failed embolisation, and for aspergilloma or ruptured aneurysm.
• Pulmonary artery bleeding needs embolisation by coils.

Cause directed treatment.

• Active tuberculosis: isoniazid 5 mg/kg (maximum 300 mg), rifampicin 10 mg/kg (maximum 600 mg), pyrazinamide 25 mg/kg and ethambutol 15 mg/kg orally daily, with pyridoxine 10 to 25 mg daily. Adjust for liver and renal function.
• Vasculitis or alveolar haemorrhage: methylprednisolone 1 g IV daily for 3 days, with rituximab or cyclophosphamide by specialists, and plasma exchange in anti-GBM disease.
• Infection: broad spectrum antibiotic such as piperacillin-tazobactam 4.5 g IV every 6 hours.

Monitoring. Continuous oximetry, arterial gas, haemoglobin every 4 to 6 hours and urine output.

Referral and escalation. Contact intensive care, interventional radiology, respiratory medicine and thoracic surgery at once.

Special groups. In cystic fibrosis, hold inhaled hypertonic saline and review airway clearance, and use tranexamic acid cautiously. In pregnancy, use the same measures with shielding during imaging.