Chapter 108

Hemoptysis

Natalie Nicole Carrier

Definition and Epidemiology

Hemoptysis refers to the expectoration of blood from the lung parenchyma or airways. It can range from a small amount of blood-streaked sputum, which is commonly seen in bronchitis, to a massive hemorrhage, which is a medical emergency because it rapidly causes death by asphyxiation. The classifications—nonmassive and massive—are based on the volume of blood loss; however, there are no uniform definitions for these categories. Hemoptysis is generally classified as nonmassive if the blood loss is less than 100 to 200 mL/day, whereas massive hemoptysis refers to more than this amount in 24 hours.¹ Massive hemoptysis is uncommon, occurring in less than 5% of patients with hemoptysis. However, the associated mortality rate ranges from 7% to 30% to as high as 58%, which demonstrates the need for urgent evaluation and management.¹^,² Even slight bleeding may signify a serious condition, such as bronchogenic carcinoma, tuberculosis, or erosion of the thoracic aneurysm. Therefore, blood loss volume is more helpful in directing management than in making a diagnosis.

The most common causes of hemoptysis in the United States are, in descending order, acute and chronic bronchitis, lung cancer, pneumonia, and tuberculosis. Similarly, these are the most common causes of hemoptysis seen in the primary care setting. However, tuberculosis is a leading cause of hemoptysis in developing countries and should be high on the list of differential diagnoses for patients who are from countries with a high prevalence of the disease or who have traveled to countries where tuberculosis is endemic.¹ Less common causes of hemoptysis include influenza viruses, malignant carcinomas, and pulmonary barotrauma secondary to diving.³^,⁴ Hemoptysis can also be a sign of an underlying hereditary disorder, such as Osler-Weber-Rendu syndrome, also known as hereditary hemorrhagic telangiectasia (HHT). HHT is an autosomal dominant disorder that is typically characterized by a triad of telangiectasia (including pulmonary), recurrent epistaxis, and a family history of the disorder.⁵

Pathophysiology

For hemoptysis to occur, there must be some communication between the airways and the blood vessels of the lungs. The lungs receive blood from two relatively independent circulations: pulmonary and bronchial. The pulmonary circulation is characterized by lower pressures and higher volumes and is supplied with mixed venous blood through the pulmonary arteries. In contrast, the bronchial circulation supplies oxygenated blood in a high-pressure, low-volume circuit.

The bronchial arteries can become enlarged and more numerous in association with a variety of inflammatory or neoplastic diseases. Chronic inflammation, often associated with infectious processes, can lead to destruction of the connective tissue of blood vessels or result in erosion through the vessel wall. Angiographic studies have revealed that hemoptysis typically originates from disruptions of the branches of the bronchial arterial tree. This is presumably related to the connection of these arteries to the proliferative nests of small vessels often found in areas of inflammation and tumors.

Clinical Presentation

It is common for patients to confuse hemoptysis with hematemesis or epistaxis. Patient history, including factors such as age, nutritional status, occupational and environmental exposures, and comorbid conditions, can be useful in differentiating among the three conditions and can help narrow the differential diagnosis. Taking a thorough travel history is important because tuberculosis and bronchiectasis appear to be decreasing as causes of hemoptysis in the United States, whereas they are still frequent causes of hemoptysis in other parts of the world. Recent travel may have also increased the risk of parasitic infections, which can cause hemoptysis.

In addition, a description of the blood and accompanying symptoms can be helpful in differentiating between hemoptysis and hematemesis. Blood from the airways is usually bright red or pink, liquid or clotted in appearance, and frothy because of the presence of surfactant. The pH is alkaline, and it tends to be mixed with macrophages and neutrophils. Blood originating in the gastrointestinal tract is usually dark red, brown, or black; it has a coffee-ground appearance and is rarely frothy. It is acidic and may be intermixed with food particles. Absence of nausea and vomiting and a history of lung disease raise the suspicion of hemoptysis, whereas the presence of nausea and vomiting and coexisting gastric or hepatic disease suggest hematemesis.¹

It is important to carefully determine the chronology and volume of hemoptysis. Quantifying blood loss may be difficult, even in patients who are clinically stable, because they are often anxious and, as a result, usually overestimate the amount of blood loss. However, every effort should be made to determine the rate and volume of blood loss, which can include observing as the patient coughs and using a graduated container. Urgent evaluation and possible hospitalization are indicated if more than 50 mL of blood has been expectorated in the previous 24 hours. For smaller amounts of blood loss, a thorough diagnostic evaluation can be initiated in the primary care setting.

Mild hemoptysis, recurring sporadically over a few years, is common in smokers, who may have chronic bronchitis with intermittent flares of acute bronchitis. However, abrupt hemoptysis associated with cigarette smoking can also be seen with bronchogenic carcinoma. A long history of small-volume, recurrent hemoptysis with little or no sputum production is suggestive of processes such as bronchogenic carcinoma, bronchial adenoma, and vascular malformation. A history of chronic sputum production suggests an infectious cause, such as bronchitis, bronchiectasis, lung abscess, or tuberculosis. Hemoptysis associated with bacterial pneumonia is suggested by an acute onset of fever, sputum production, and, commonly, pleuritic chest pain. Hemoptysis is commonly a late symptom of bronchogenic carcinoma and is preceded by a chronic cough, fatigue, and constitutional symptoms. Environmental exposure to asbestos, arsenic, chromium, nickel, and certain ethers can increase the risk for hemoptysis.¹ Occupational history may be helpful in elucidating the cause of hemoptysis. For example, after repetitive deep dives, breath-hold divers are often affected by a common syndrome characterized by typical symptoms such as cough, sensation of chest constriction, blood-striated expectorate (hemoptysis), and, rarely, an overt acute pulmonary edema syndrome, often together with various degrees of dyspnea. Similar clinical features had been previously observed in scuba divers, swimmers, and athletes engaged in strenuous efforts during terrestrial sport activities.⁴ A travel history may be helpful. Tuberculosis is endemic in many parts of the world, and parasitic causes should be considered.¹

Physical Examination

The presence of a fever suggests infection. A thorough examination of the ears, nose, and throat can detect upper airway sources of bleeding, such as laryngeal carcinoma lesions. Cervical, supraclavicular, or axillary adenopathy raises the suspicion of an intrathoracic malignant neoplasm. The presence of stridor or findings suggestive of chronic obstructive pulmonary disease, congestive heart failure, or pneumonia can be determined by auscultation of the chest.

Localized wheezing may indicate a local obstruction, foreign body, or bronchogenic carcinoma. A pleural friction rub may be the only sign of pulmonary infarction associated with a pulmonary embolism. Isolated crackles are nonspecific for the location of the primary disease because they may represent an inflammatory reaction to blood aspirated from another site.

Digital clubbing is suggestive of chronic lung disease, such as bronchiectasis or malignant neoplasm. Cardiac examination may help determine the presence of mitral stenosis. Localized adenopathy, especially a supraclavicular node, may be indicative of a lung malignant neoplasm. A bleeding disorder is suggested by the presence of petechiae or ecchymoses.