What are the causes of pulmonary hemorrhage (pulmonary bleeding)?

From the Guidelines

Pulmonary hemorrhage is most commonly caused by malignant lesions involving the airways, such as lung cancer, as well as other conditions like tuberculosis, bronchiectasis, and autoimmune disorders. The mechanisms responsible for hemoptysis include growth of new blood vessels (neovascularization) in and around the neoplasm, exfoliation of surface tumor with exposure of underlying blood vessels, tumor necrosis, trauma from cough, and iatrogenic procedures (such as bronchoscopy) and formation of airway-vascular fistula 1.

Causes of Pulmonary Hemorrhage

• Malignant lesions involving the airways, such as lung cancer
• Tuberculosis
• Bronchiectasis
• Autoimmune disorders
• Trauma from cough
• Iatrogenic procedures (such as bronchoscopy)
• Formation of airway-vascular fistula

According to a study published in the Journal of the American College of Radiology, massive hemoptysis in the developed world shows a higher prevalence of malignancy over tuberculosis etiologies 1. The most common causes of massive hemoptysis are malignancy, tuberculosis, and bronchiectasis, with over 90% of cases due to a systemic arterial supply.

Management of Pulmonary Hemorrhage

• Stabilizing the patient with oxygen therapy, mechanical ventilation if needed, and correction of any coagulation abnormalities
• Specific medications such as corticosteroids and immunosuppressants for inflammatory and autoimmune causes
• Antifibrinolytics such as tranexamic acid to control bleeding
• Bronchoscopy for diagnosis and to clear blood from airways
• Bronchial artery embolization (BAE) as a safe and effective intervention for the treatment of massive hemoptysis 1

In a study of 26 patients with either lung cancer or lung metastasis causing hemoptysis, treatment with BAE resulted in a 75% immediate success rate 1. BAE is now universally accepted as a safe and effective intervention for the treatment of massive hemoptysis, with success rates ranging from 75% to 100%.

Overall, prompt identification and treatment of the specific cause of pulmonary hemorrhage is essential for preventing recurrence and reducing mortality. The management of pulmonary hemorrhage should prioritize stabilizing the patient, controlling bleeding, and addressing the underlying cause.

From the Research

Causes of Pulmonary Hemorrhage

The causes of pulmonary hemorrhage can be categorized into localized and diffuse alveolar hemorrhage.

• Localized pulmonary bleeding is often caused by:
  • Lung cancer 2
  • Infections 2
  • Anticoagulant therapy 2
  • Bronchiectasis 2
• Diffuse alveolar hemorrhage is mostly due to:
  • Pulmonary vasculitis 2
  • Connective tissue disease 2
  • Pulmonary metastasis 2
  • Congestive heart failure 2
  • Coagulation disorders 2 Other causes of pulmonary hemorrhage include:
• Cystic fibrosis 3
• Severe trauma 4
• Iatrogenic causes 5
• Mucosal airway bleeding 5
• Pulmonary embolism 5
• Major aortopulmonary collateral arteries 5

Etiology and Treatment

The treatment policy for pulmonary hemorrhage is determined by its severity and etiology, as well as the health status of the patient 6.

• Medical hemostatic therapy is often used to treat pulmonary hemorrhages 6
• Surgical treatment may be used if medical therapy is ineffective 6
• Other treatments include:
  • Bronchoscopic therapy 2
  • Bronchial artery embolization 2
  • Surgery 2
  • Immunosuppressive therapy for vasculitis 2
  • Medical treatment of coagulation disorders 2
  • Inhaled tranexamic acid for critically ill pediatric patients 5
  • Repeated alveolar lavage combined with extracorporeal membrane oxygenation for massive pulmonary hemorrhage due to severe trauma 4