by Carlos Salvarezza

Definition

Hemoptysis is known as hemorrhagic expectoration from the lower respiratory tract (subglottic localization). It is a relatively frequent respiratory symptom, sometimes life-threatening for patients, an expression of various conditions and frequently, a manifestation of significant illness.

It is usually a mild to moderate bleeding, self-limiting, requiring investigation of the underlying cause. History, physical examination, and chest radiography, together with knowledge of comorbid diseases and demographic factors, guide the evaluation of patients with mild to moderate hemoptysis.

In its severe and massive forms, hemoptysis constitutes an extremely serious condition with high morbidity and mortality, which generates great anxiety in both the patient and the treating physician. The massive form occurs in less than 5% of patients with hemoptysis, being life-threatening with a requirement for control in intensive therapy (UTI) and emergency bronchoscopic evaluation for lateralization or localization of the bleeding site. It should be noted that in these cases the patients die due to respiratory failure due to suffocation caused by the flooding of the tracheobronchial tree, rather than due to hypovolemic shock, which is explained by the low volume of the central airway of only 150 cm3. These facts make it necessary to have clear guidelines for the initial management of massive and potentially fatal hemoptysis. Management in these cases must be individualized and requires prompt interdisciplinary consultation. The availability of endobronchial techniques to stop bleeding and bronchial arterial embolization has improved the ability to control massive bleeding in the short term and decreased the need for emergency surgical treatment.

Pathophysiology. Classification and causes

The blood that goes through the lungs comes from two of the following circuits:

• Low pressure pulmonary circulation (15-20 mmHg systolic and 5-10 mmHg diastolic).
• Bronchial circulation: circuit under systemic pressure.

There are generally one to two bronchial arteries for each lung, typically originating from the aorta and less commonly from the intercostal arteries.

Normally both circulations are interconnected. These anastomoses allow the bronchial arterial blood to drain into the left heart. The volume of these communications can be increased in chronic inflammatory conditions such as tuberculosis, bronchiectasis, or cystic fibrosis. In these circumstances, new collaterals may also develop from the bronchial arteries or from other systemic intrathoracic arteries.

These collaterals can decrease the therapeutic success of embolization of the bronchial arteries to control massive hemoptysis. The bronchial arteries are generally the main source of hemoptysis.

Classification

According to the amount of hemorrhagic expectoration, it is classified into:

• Hemoptoic sputum or mild hemoptysis: less than 30ml / day.
• Frank or moderate hemoptysis: between 30 and 150ml / day.
• Severe hemoptysis: more than 150ml / day.
• Massive hemoptysis (at least one of the following criteria)
  • 200ml or more at one time.
  • 600ml or more in 24 hours.
  • Symptoms or signs of hypovolemia.
  • Signs of respiratory failure or drowning from flooding of blood in  the airway.

Etiology: The frequency of the causes of hemoptysis varies according to the demographic characteristics of the population considered as a sample. In the USA, the most frequent etiologies are bronchial exacerbation of COPD and bronchogenic carcinoma. In underdeveloped countries, the number one cause remains TB. Bronchiectasis, a very frequent cause of hemoptysis in the past, has been progressively decreasing as a result of better control of respiratory infection and thanks to childhood vaccination programs. In cases of chest X-ray without evidence of injury, about 80% of hemoptysis is due to canalicular infection.

It should be noted that up to 5-20% of hemoptysis cases remain without etiological diagnosis despite the complete study of them. These are called idiopathic or cryptogenetic hemoptysis.

Causes of hemoptysis

• Infections ( ~ 60%)
  • Bronchitis (acute and chronic)
  • Bronchiectasis
  • Tuberculosis
  • Pneumonia
  • Lung abscess
• Neoplastic (~ 20%)
  • Carcinoma broncogénico
  • Bronchial adenoma
  • Lung metastases
• Cardiovascular (~ 5%)
  • Lung infarction
  • Mitral stenosis
  • Arteriovenous malformations
• Others (Miscellaneous)
  • Goodpasture syndrome
  • Vasculitis and connective tissue diseases
  • Hemorrhagic diathesis
  • Trauma and foreign bodies
  • Iatrogenic (FNA, bronchial biopsies)
  • Pneumoconiosis, hemosiderosis
  • Malformations (bronchopulmonary sequestration)
  • Pulmonary endometriosis (catamenial hemoptysis)
  • Lung hemorrhage secondary to cocaine abuse

Anamnesis and physical examination of the patient with hemoptysis

The initial attitude towards hemoptysis is based on its confirmation, the assessment of its severity and its diagnostic approach.

First of all we must confirm that the blood comes from the subglottic respiratory territory and not from the ENT area (upper airways) or the digestive tract. For this, it will be based on the anamnesis and exploration of the ENT area, in addition to the differential characteristics between hemoptysis and hematemesis shown in the following table.

Differential Diagnosis Table Between Hemoptysis And Hematemesis

It's important to put attention on:

• A heavy hematemesis can be red and cause a cough.
• Gastric hemorrhagic content aspirations can be suffered and then they are expelled with a cough.
• Blood from the airway can be swallowed and then expelled with vomit.

Concomitantly with the determination that the bleeding is subglottic, the assessment of the state of severity of the hemoptysis picture must be performed. The presence or absence of hemodynamic instability (hypotension due to hypovolemia) or signs of respiratory failure that require, regardless of the amount of hemoptysis, the urgent transfer of the patient to the reference hospital center will be determined, adopting life support measures. The most accepted hospital admission criteria by most of the authors are the following:

• Mild but persistent hemoptysis.
• Hemoptysis greater than 30ml / day.
• Hemoptysis associated with disease requiring hospital admission (lung abscess, thromboembolism of the lung, etc.).

Once confirmed that this is a case of hemorrhage from the subglottic respiratory tract, the amount being assessed as mild and the absence of signs of severity, they try to identify the etiology of the condition. For this, the anamnesis and the physical examination are started.

The age of the patient is an important fact, so that in a patient younger than 40 years the most frequent causes are inflammatory and infectious, while in those older than 40 years (especially if they are smokers) the incidence must be taken into account of neoplastic causes. Other data of interest to interrogate are:

• History of respiratory diseases.
• Previous episodes of hemoptysis.
• General clinical picture.
• Volume, speed and time of bleeding.
• Fever and its characteristics.
• Pleuritic chest pain and dyspnea.
• Chronic expectoration.
• Taking blood thinners.
• Tobacco use.
• Presence of other bleeding sites.
• History of neoplastic or systemic diseases.
• Drug addiction (cocaine abuse).

The physical examination begins with the inspection of the oral cavity and the nostrils to rule out bleeding from the upper airways (VAS); cardiac auscultation to assess signs of heart failure or heart valve disease; Lung auscultation: crepitant rales point to pneumonia in a specific clinical setting or the focus of bleeding; Roncus and scattered wheezing are present in bronchitis and fixed roncus or wheezing localized in bronchial obstruction by tumors or foreign bodies.

Diagnostic methodology of hemoptysis

After a thorough anamnesis and an exhaustive physical examination, usually guiding the cause of the bleeding, a chest and profile radiography is performed, which is the most useful complementary test for the study of hemoptysis in primary care. Whenever possible, it should be evaluated by comparing it with previous Rx.

Chest radiography is very useful in finding parenchymal lesions (cavitary or infiltrative, tumorous, atelectasis). In the case of intraalveolar bleeding, a reticulonodullar pattern can be observed. Chest X-ray is normal in 20-30% of hemoptysis cases. In general, biochemical analyzes are requested at the same time as the chest plate to evaluate the magnitude and chronicity of bleeding, complete urine and renal function (uremia and creatininemia) through the CBC to detect diseases that cross-affect the kidney and the lung such as Goodpasture's disease or Wegener's vasculitis, coagulation profile (TP, KPTT, Coagulation Time and bleeding, platelets) for diagnosis of coagulopathies.

When the chest radiograph is normal, the most frequent causes are inflammatory and the possibility of finding a tumor in the BFC is generally less than 5%. The risk factors that have been most associated with the finding of a neoplasm and in which bronchofibroscopy is indicated are:

• Age over 40 years.
• Smoker of more than 40 packs / year.
• Hemoptysis duration more than 1 week.
• Bleeding greater than 30ml / day.
• Changes in chest Rx.

BCF is a particularly useful diagnostic method, allowing the location of the bleeding site and the visualization of the endobronchial pathology causing it, as well as the taking of biopsies for anatomopathological and bacteriological studies and certain therapeutic procedures. It has proven efficacy in the evaluation of patients with central endobronchial disease, with a certain diagnosis in 95% of primary endoscopically visible tumors. BCF has surprisingly low accuracy in diagnosing hemoptysis in patients with non-localizing or normal chest X-rays. In contrast, BCF is routinely diagnostic in patients with localizing chest X-rays. The optimal time for performing BCFes within 48 hours of bleeding.

BCF is a diagnostic test that can be dispensed with in the study of hemoptysis only in specific cases, such as: - a non-smoking patient under the age of 40 with a single hemptoic episode, no other associated symptoms and with normal chest X-ray and - patient with a known diagnosis (for example, bronchiectasis) with mild recurrent hemoptysis and without significant changes in the medical history and chest radiography.

The thoracic CT (with fine cuts): It is a non-invasive imaging test that allows us to better see the radiological pattern, detect small lesions that are not appreciable on conventional radiography, exploration of the peripheral airways (where it is not accessed with BCF ) and the evaluation of the pulmonary hilies and the mediastinum, etc.

There is no consensus among the different authors on the order in which the 2nd level tests should be performed (BCF and TAC); What is clear is that they are complementary diagnostic methods that when used together improve the diagnostic profitability in the study of hemoptysis caused by a wide group of lung diseases.