Hemoptysis

General Principles

Hemoptysis is the coughing up of blood or blood-stained mucus. It is a sign of underlying pulmonary pathology. It can be life threatening and requires rapid identification, workup, and treatment.

Definition

  • True hemoptysis is expectoration of blood from the lower respiratory tract below the glottis.
  • Massive or life-threatening hemoptysis:
    • Is usually defined by volume per unit time.
    • It is most commonly defined as >600 mL of blood expectorated per 24 hours.1,2
    • Volumes of >100 mL in 24 hours associated with gas exchange abnormality, airway obstruction, or hemodynamic instability are also considered life threatening.

Classification

Clinically, hemoptysis is usually classified as being massive/life threatening or not (see above). It may also be classified by the anatomic location of the bleeding.

  • Airway
  • Parenchyma
  • Vascular
  • Combination

There are various other classifications in the literature based on appearance, frequency, rate, volume, and potential for clinical consequences of the hemoptysis that may suggest an underlying etiology or predict outcome and thus help guide in diagnosis and management. However, considerable overlap exists in the clinical presentation both within and between etiologies.

Etiology

See Table 10-9.

Table 10-9: Etiology of Hemoptysis
LocationEtiology
AirwayBronchitis, bronchiectasis, malignancy, foreign body, trauma, pulmonary endometriosis, and broncholithiasis
ParenchymalPneumonia, vasculitides, and pulmonary hemorrhage syndromes (antineutrophil cytoplasmic antibody–positive vasculitis, Goodpasture syndrome, systemic lupus erythematosus, diffuse alveolar hemorrhage, acute respiratory distress syndrome)
VascularElevated pulmonary venous pressure (LV failure, mitral stenosis), pulmonary embolism, arteriovenous malformation, pulmonary arterial trauma (i.e., pulmonary arterial catheter balloon overinflation), varices/aneurysms, vasculitides, and pulmonary hemorrhage syndromes
Multiple locationsCavitary lung disease (TB, aspergilloma, lung abscess), thrombocytopenia, disseminated intravascular coagulation, anticoagulants, antiplatelets, cocaine and other inhaled agents, lung biopsy, bronchovascular fistula, bronchopulmonary sequestration, and Dieulafoy disease
OtherUp to 50%. Favorable prognosis, in general. Up to 4% eventually diagnosed with malignancy3,4

Epidemiology

The incidence of each cause of hemoptysis varies considerably. Table 10-10 lists some of the most common causes of hemoptysis.5,6

Table 10-10: Epidemiology of Hemoptysis
EtiologyIncidence (%)
Bronchitis2–37
Bronchiectasis1–37
TB and cavitary lung disease2–69
Malignancy2–24
Pneumonia1–16
Pulmonary embolus3
Pulmonary edema4
Idiopathic2–50

Pathophysiology

The source of hemoptysis depends on the etiology and location of the underlying pathologic process.

  • The pulmonary arterial circulation supplies 99% of all blood flow to the lung parenchyma under low pressure. Disruption can result in minor hemoptysis or more life-threatening hemoptysis due to processes such as vasculitis, diffuse alveolar hemorrhage, pulmonary embolism, acute respiratory distress syndrome, arteriovenous malformation (AVM) rupture, pulmonary artery catheter trauma, severe mitral stenosis, LV failure, or Rasmussen aneurysm (pulmonary artery aneurysm associated with TB).
  • The bronchial arterial circulation arises from the aorta and intercostal arteries. It supplies high-pressure blood flow to the lungs but accounts for only 1% of pulmonary blood flow. Disruption by a foreign body, tumor invasion, fungal invasion, or denuded airway mucosa can result in massive, life-threatening hemoptysis. Bleeding from the bronchial circulation may account for up to 88% of all cases of massive hemoptysis.

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