Hemoptysis is the coughing up of blood or blood-stained mucus from the bronchi, larynx, trachea, or lungs. In other words, it is airway bleeding. This can occur with lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, and certain cardiovascular conditions. The primary danger comes from choking, rather than blood loss.
The most common causes of hemoptysis in adults are chest infections such as bronchitis or pneumonia. In children, hemoptysis is commonly caused by the presence of a foreign body in the airway. Other common causes include lung cancers and tuberculosis. Less common causes include aspergilloma, bronchiectasis, pulmonary embolism, pneumonic plague, and cystic fibrosis. Rarer causes include hereditary hemorrhagic telangiectasia (HHT or Rendu-Osler-Weber syndrome), Good pasture's syndrome, and granulomatosis with polyangiitis. A rare cause of hemoptysis in women is endometriosis, which leads to intermittent hemoptysis coinciding with menstrual periods in 7% of women with thoracic endometriosis syndrome. Hemoptysis may be exacerbated or even caused by overtreatment with anticoagulant drugs such as warfarin.
Hemoptysis must be differentiated from expectorated blood originating from the nasopharynx or gastrointestinal tract. Hemoptysis can result from infections, malignancies, or vascular disease. Acute bronchitis is the most common cause of hemoptysis in the United States; tuberculosis is the leading cause worldwide. Hemoptysis originating from the alveoli is known as diffuse alveolar hemorrhage (DAH). DAH can be caused by inflammatory diseases including granulomatosis with polyangiitis, systemic lupus erythematous, and anti-glomerular basement membrane disease. Within the first 100 days after bone marrow transplant, inflammatory DAH can cause severe hypoxemia. No inflammatory DAH usually results from inhalational injuries from toxic exposures, such as smoke inhalation or cocaine.
Hemoptysis most commonly originates from small- to medium-sized bronchi. Because the bleeding source is usually bronchial arteries, there is potential for rapid blood loss. Airway hemoptysis is often caused by viral or bacterial bronchitis. Patients with bronchiectasis have an increased risk of hemoptysis. Pneumonia can cause hemoptysis, especially if cavitation (e.g., tuberculosis) and/or necrotizing pneumonia. Cancers developing in central airways (e.g., squamous cell carcinoma, small-cell carcinoma, and carcinoid tumors) often cause hemoptysis. Cancers that metastasize to the lungs cause hemoptysis less commonly. Pulmonary vascular sources of hemoptysis include congestive heart failure with pulmonary edema, which usually causes pink, frothy sputum. Pulmonary embolism with infarction and pulmonary arteriovenous malformations are additional pulmonary vascular etiologies to consider.
The approaches to assess and treat hemoptysis are - History should determine whether the bleeding source is likely the respiratory tract or an alternative source (e.g., nasopharynx, upper GI tract). The quantity of expectorated blood should be estimated because it influences the urgency of evaluation and treatment. Massive hemoptysis, variably defined as 400 mL within 24 h or 100−150 mL at one time, requires emergent care. The presence of purulent or frothy secretions should be assessed. History of previous hemoptysis episodes and cigarette smoking should be ascertained. Fever and chills should be assessed as potential indicators of acute infection. Recent inhalation of illicit drugs and other toxins should be determined.
Physical examination should include assessment of the nares for epistaxis, and evaluation of the heart and lungs. Pedal edema could indicate congestive heart failure if symmetric, and deep-vein thrombosis with pulmonary embolism if asymmetric. Clubbing could indicate lung cancer or bronchiectasis. Assessment of vital signs and oxygen saturation can provide information about hemodynamic stability and respiratory compromise.
Radiographic evaluation with a chest x-ray should be performed. Chest CT may be helpful to assess for bronchiectasis, pneumonia, and lung cancer; with CT angiography, pulmonary embolism and location of bleeding may be determined. Laboratory studies include a complete blood count and coagulation studies; electrolytes, renal function, and urinalysis should be assessed. Sputum should be sent for Gram’s stain and routine culture as well as acid-fast bacillus (AFB) smear and culture. Bronchoscopy is often required to complete the evaluation. In massive hemoptysis, rigid bronchoscopy may be necessary.
Massive hemoptysis may require endotracheal intubation and mechanical ventilation to provide airway stabilization. If the source of bleeding can be identified, isolating the bleeding lung with an endobronchial blocker or double-lumen endotracheal tube is optimal. The patient should be positioned with the bleeding side down. If bleeding persists, bronchial arterial embolization by angiography may be beneficial; however, the risk of spinal artery embolization is an important potential adverse event. As a last resort, surgical resection can be considered to stop the bleeding.