Haemoptysis is best described as “coughed up blood”. Often haemoptysis is not a disease itself but can signify a variety of underlying problems and should therefore be properly assessed by a doctor. Blood can manifest in many different forms, however often it is frothy and bright red.
The amount can be as minimal as blood stains in the spit (sputum) to more obvious larger amounts of blood or clots that would need a more immediate attention of a doctor. Amounts larger than 600ml are usually regarded as massive haemoptysis and do require emergency medical attention.
Haemoptysis should not be confused with haematemesis – which describes the vomiting of blood and, unlike haemoptysis, is often associated with nausea and vomiting as well as food particles that can be seen. The colour of the blood can range from bright red to dark, almost black dotted (“coffee ground” like) and should be best assessed by a physician as well.
The lungs, which are situated in the chest with the heart sitting between the right and the left lung lobe, usually get their blood supply from 2 different sources.
Most of the blood (95%) comes from the low-pressure pulmonary arteries and ends up in the pulmonary capillary bed, where gas is exchanged. A small portion (about 5%) of the blood supply circulates via high-pressure bronchial arteries, which come from the aorta and supply the structures of the major airways with blood.
In most cases of haemoptysis the blood originates from the pulmonary capillary bed (low pressure) and only in more rare cases (e.g. due to trauma or injury) from the high-pressure bronchial arteries.
If large volumes of blood enter the airway there is a risk of drowning and massive haemoptysis may result in severe anaemia, both of which are life threatening.
The reasons for haemoptysis can vary widely, common causes of haemoptysis include:
Ideally, all patients presenting with haemoptysis should undergo further tests to rule out any underlying sinister causes. Besides the routine physical examination, your doctor will order a chest x-ray as a first assessment. If that is normal, further investigations might be necessary such as a computed tomography (CT) of the chest. Often a bronchoscopy – an endoscopic examination of the airways – is performed to identify a source of the bleeding or to even get a tissue biopsy from suspicious lesions.
Besides these, your doctor might order an electrocardiogram (ECG) or echocardiogram (Echo) if a heart problem or a pulmonary embolism is suspected.
Other tests such as sputum analysis and culture, full blood count and tests of the blood clotting ability might be ordered. In unclear cases more sophisticated tests such as CT angiograms (CT to show specific blood vessels) or even Positron Emission Tomography/CT (PET or PET/CT) may be ordered to further investigate.
Depending on the underlying cause of the haemoptysis the treatment might range from observation and antibiotic treatment to more invasive treatment such as bronchoscopy or open surgery.