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Hemoptysis is the expectoration of blood. Severity ranges from mild to severe, and it can be difficult to stop. The challenge is to stabilize the patient while simultaneously determining the source and providing treatment. Most cases of hemoptysis are minor and resolve spontaneously; predicting which individual will develop massive, large-volume bleeding is difficult. Determining the cause and treatment of hemoptysis requires a multidisciplinary approach.1

Assessing the amount of expectorated blood is difficult; patients may either exaggerate or be unable to quantify the amount. The definition of massive hemoptysis varies, with reported ranges from 100 mL per 24 hours to >1000 mL per 24 hours,2,3 and a midpoint value of 600 mL per 24 hours accepted by many.4 However, because even small volumes of blood can cause asphyxiation, any hemoptysis requires prompt attention.5 Morbidity and mortality depend on the rate of bleeding, the ability of the patient to clear the blood, and the presence of underlying lung disease, which potentiates the effects of blood in the airways. We define “minor” hemoptysis as self-limited, small-volume expectoration of blood in a patient with no comorbid lung disease, normal/stable oxygenation and ventilation, normal vital signs, and no risk factors for continued bleeding.


Hemoptysis results from disruption of blood vessels within the walls of the airways, from trachea to bronchi, bronchioles, and the lung parenchyma (Table 63-1). The pulmonary arteries account for 99% of the blood flow to the lungs but are a low-pressure system involved in gas exchange and rarely the source of massive hemoptysis. The bronchial arteries accounts for only 1% of the blood flow to the lungs but 90% of the cases of hemoptysis because it is a high-pressure system.6 Bronchial arteries typically branch off the thoracic aorta at thoracic vertebrae levels 5 and 6 and are responsible for supplying oxygen and nutrients. Approximately one third of the time, they are ectopic and originate from other parts of the aorta. Extensive anastomoses occur between the bronchial and pulmonary arteries, producing a physiologic right-to-left shunt composing 5% of cardiac output.7

TABLE 63-1Causes of Hemoptysis

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