creation date: 2025-10-30 17:29
tags: Workups
Hemoptysis
Background
Hemoptysis refers to blood brought up by spit which originates from the lungs or bronchial tubes (lower lung).
Pathophysiology
Blood supply to the lungs is derived from the pulmonary and bronchial arteries, with the rare exception of nonbronchial systemic circulation supply (<5% of patients).
The pulmonary arterial circulation is a low-pressure system supplying the lung parenchyma and generally result in non-life-threatening hemoptysis. The bronchial arteries supply approximately 2% of the lung vasculature (primarily the endobronchial tree) but due to the high-pressure system from systemic circulation, often results in life-threatening hemoptysis and is the most likely source of massive hemoptysis.
In most cases, some insult results in erosion and damage to a blood vessel which causes bleeding. In cases of malignancies, bleed may result from tumour angiogenesis or tumour invasion of vasculature.
Differential Diagnosis
Alternatives to hemoptysis consist of:
- Pseudohemoptysis (blood originating from upper airway)
- Hematemesis (vomiting of blood from GI tract due to internal bleeding)
Non-life threatening hemoptysis
While the following list is generally mild and non-life threatening, in certain situations, can result in life-threatening volumes of bleed.
Airway diseases:
- Bronchitis - during acute phase
- Bronchiectasis - minor amount in phlegm during chronic phase
- Bronchial neoplasm
- Foreign bodies
- Broncholiths
- Airway infections with herpes virus or fungus
- Fistula (between blood vessel and tracheobronchial tree)
- Dieulafoy lesion (dilated aberrant submucosal vessel)
Pulmonary parenchymal diseases:
- Infection (eg. tuberculosis, mycetoma, lung abscess, necrotizing pneumonia)
- Rheumatic and immune disorder
- Genetic disorders of connective tissues (eg. Ehlers-Danlos syndrome)
- Catamenial hemoptysis (coincident hemoptysis with menses due to intrathoracic endometriosis)
Pulmonary vascular disorders:
- Elevated pulmonary capillary pressure (typically venous) - due to LV failure, mitral stenosis, or other conditions
- Pulmonary arteriovenous malformation (PAVM) - possibly life threatening (eg. during pregnancy)
- Pulmonary or bronchial artery aneurysm
- Pulmonary artery pseudoaneurysms
- Pulmonary capillaritis
- Pulmonary embolism (hemoptysis usually mild and not life-threatening)
Trauma and bleeding disorders:
- Bleeding disorders with use of antiplatelet or anticoagulation
- Airway or parenchymal trauma
- Iatrogenic injury
Drugs and toxins:
- Cocaine-induced pulmonary hemorrhage (smoking of free-base cocaine; “crack”)
- Bevacizumab treatment
- Nitrogen dioxide exposure
- E-cigarette exposure
Life threatening hemoptysis
Life-threatening hemoptysis is generally defined as hemoptysis that causes significant airway obstruction, significant gas exchange alterations, or hemodynamic instability. A threshold of around 200 mL of blood (nearly a cup) in 24 hours or a rate of ≥100 mL/hr is clinically used.
Any etiology listed above can potentially cause life-threatening hemoptysis. However, common causes are:
- Bronchiectasis
- Tuberculosis
- Fungal infections
- Bronchogenic carcinoma
Other possible causes are:
- Lung infection
- Immunologic lung diseases
- Chemotherapy and bone marrow transplantation
- Pulmonary vascular diseases
- Acquired and iatrogenic trauma
Cryptogenic hemoptysis
In up to 30% of patients, no causes can be identified even after careful evaluation.
Initial Evaluation
History
History should assess:
- Pattern and severity of hemoptysis (amount, onset, link with menses)
- Character of the hemoptysis (phlegm colour)
- Degree of respiratory impairment (presence of dyspnea)
- Clues regarding etiology (infectious symptoms, bleeding from nose/gum/stomach/rectum, skin rash, bone pain, systemic symptoms)
- Cigarette smoking history, drug use
- Comorbidities
- Family history (blood clots or bleeding disorders)
Associated findings may point towards a specific diagnosis
Physical Exam
Physical exam should assess degree of respiratory compromise if applicable. A thorough ENT exam for blood sources in the mouth or nose should be done.
Inspection for blood around nose and of sputum may provide clues. Additionally, a detailed cardio-resp exam can elucidate possible etiologies.
Investigations
Evaluation should be directed based on history and physical to identify possible cause suspected. This generally begins with a chest radiograph.
Normal radiograph may suggests non-pulmonary causes that require ENT/GI referral or pseudohemoptysis.
In cases of abnormal chest radiograph or normal radiograph with suspicion of lung malignancy or pulmonary embolism, the following laboratory testing should be obtained:
- CBC
- Coagulation panel (INR, PTT)
- BUN, creatinine
- LFTs
- D-dimer if PE suspected
- BNP and ECG if heart failure suspected
- Urinanalysis if renal concerns
Additionally, CT scan with IV contrast can evaluate lung vasculature (with exception to PE in which CTPA is used).
In cases where etiology is still unclear or normal but suspicion remains, flexible bronchoscopy can confirm source of bleeding.
Life-threatening hemoptysis
The exact work up will depend on the stability of the patient. In general, the investigations follow that of non-life-threatening hemoptysis but will also include at some point:
- Bronchoscopy
- CT chest