Lung bleedingR04.8

Pulmonary bleeding is the discharge of blood from the pulmonary vessels into the lung tissue.

The annual incidence of lung bleeding is about 0.1% of outpatients and about 0.2% of inpatients. The disease is a potentially life-threatening emergency and has a high mortality rate.

It occurs predominantly in patients with an average age of 62 years. The gender ratio is 2 to 1 (male to female).

Severe lung bleeding accounts for only about 10% of cases. The mortality rate of such haemoptoe is between 50 - 100 % with conservative treatment. Death usually occurs due to asphyxia long before hemorrhagic shock occurs.

The mortality rate for massive pulmonary hemorrhage is between 7.1 % and 18.2 % with surgical treatment and rises to 40 % if surgery is performed as an emergency procedure.

Mild haemoptysis occurs in about 90 % and is self-limited in up to 90 %.

Angiographic and bronchoscopic studies have shown that pulmonary hemorrhages originate from the bronchial arteries to about 90% and are fed to about 5% each from pulmonary and non-bronchial systemic arteries.

In Western countries, about 50% are cryptogenic and the other 50% are caused by diseases of different genesis.

Caused by pulmonary diseases :

• inflammatory respiratory diseases 25.8%, of which tuberculosis with 2.7% and aspergillosis with 1.1%
• Bronchial carcinoma or lung metastases 17.4% (most frequent cause of haemoptysis in male smokers > 45 years of age)
• Bronchiectasis 6,8 %
• Pulmonary edema, mitral stenosis 4.2 %
• Vasculitides (e.g. granulomatosis with polyangiitis, Goodpasture syndrome, M. Becet) approx. 0.2 % and others

caused by cardiovascular diseases:

• Pulmonary artery embolism 2.6 %
• vascular malformations 0,2 %
• idiopathic pulmonary haemosiderosis 0.1% and others

due to other causes:

• iatrogenic (after right heart catheterisation, after lung biopsies, after endoscopic lung surgery, anticoagulation therapy or thrombolysis treatment) 3.5 %
• Trauma 0.7%
• Foreign bodies 0.1 % and others

Outside the western world, haemoptysis or haemoptoe is by far the most common cause of tuberculosis and bronchiectasis.

Leading symptom of pulmonary hemorrhage are haemoptysis (< 100 ml blood in 24 hours) or haemoptoe (>100 ml blood in 24 hours) with or without mucus. Other typical symptoms are:

• it empties light red, foaming blood during expectoration
• Breathing difficulties up to massive dyspnoea (even 150 - 200 ml of blood can quickly lead to a considerable gas exchange disturbance)
• thoracic warmth

Contrast-enhanced multi-line computed tomography is superior to digital subtraction angiography in the detection of bronchial and non-bronchial arteries. The cause of bleeding is successful in 60% - 77% of cases. In addition, the bleeding can be assigned to the corresponding flap in 63% - 100% of cases.

Multi-line computed tomography can be used to reduce the radiation dose, the intervention time and the amount of contrast medium in subsequent bronchial artery embolization.

It is recommended to perform the reconstruction in the pulmonary and soft tissue window (5 mm) and in thin-layer reconstructions (1 mm) to locate the ostia of the bronchial arteries.

Numerous post-processing techniques (e.g. multiplanar reconstructions (MPR), three-dimensional (3D) volume and surface imaging ("shaded-surface display" (SSD) or maximum intensity projections [MIP]) allow better visualization of pathological lung structures and better planning of therapeutic interventions such as bronchoscopy, bronchial artery embolization or surgery.

The drawback is the radiation exposure for the patient and the inability to detect endobronchial neoplasia in blood accumulations there. Bronchoscopy is used for complementation.

CT angiography should be performed with bolus tracking and contrast medium injection in breath holding technique. By using ECG triggering, pulsation artifacts can be minimized. In retrospective approaches, this requires a relatively high dose of 8.2 - 31.8 mSv in adults. With prospective triggering, values between 2.1 - 9.2 mSv are sufficient.11

• careful inspection of the mouth and throat area to exclude a source of bleeding in the upper gastrointestinal tract
• Laboratory values (blood count, quick value or INR value, PTT, thrombocytes, blood gases and blood group determination)
• if suspected, laboratory chemical autoimmune diagnostics
• X-ray thorax in 2 planes (sufficient for mild haemoptysis and clear anamnesis)
• contrast medium-supported multi-line computer tomography with CT angiography. As Yoon W (see below) mentions, it is now recommended to perform CT before bronchoscopy: "Many researchers currently suggest that CT should be performed prior to bronchoscopy in all cases of massive hemoptysis". (Yoon W et al (2002) Bronchial and nonbronchial systemic artery embolization for life-threatening hemoptysis: a comprehensive review. RadioGraphics 22nd (RSNA) Radiological Society of North America 1395-14099

Bronchoscopy is performed for both diagnostic and therapeutic purposes.

It can be carried out in flexible or rigid technique. The sensitivity of this examination for the localisation of a bleeding source, which is located in the bronchoscopically visible area or peripherally thereof, is 73% - 93%. However, clarification of the cause of haemoptysis is only possible in 2.5% - 8% of cases.

Bronchoscopically visible bleeding sources in the central airways can not only be detected but also treated locally.

If the sources of bleeding are located in the periphery, bronchoscopy can be used to narrow down the bleeding (lung segment, lobe or wing) for any subsequent therapeutic measures (such as bronchial artery embolization or surgery) and also for the removal of material for microbiological, histological or cytological diagnosis.

• Bleeding from the mouth and throat
• Bleeding of the upper gastrointestinal tract (symptoms: haematinized blood, acidic pH, possible food residues, nausea, abdominal pain)

Currently, there is neither a guideline nor meta-analyses for pulmonary hemorrhage. According to literature references the following procedure is recommended:

• the most important first measure is the administration of oxygen to ensure adequate oxygenation of the lungs
• Positioning of the patient on the diseased side (if immediately detectable)
• Measurement and control of vital parameters
• if necessary, immediate intubation with a large-lumen tube (enables rapid removal of blood from the airways) or with a double tube
• or careful sedation (the coughing stimulus must not be suppressed)
• Volume substitution
• Provision of blood reserves
• if necessary, consultation in thoracic surgery

for light bleeding:

• often a treatment of the causal diseases (e.g. infections) is sufficient
• Optimisation of the coagulation status, e.g. by antifibrinolysis therapy with tranexamic acid (initially 10 - 20 mg/kg bw; subsequently 1 - 2 mg/kg bw/h)

for bleeding from the central airways:

• Use interventional measures to stop bleeding from sources of bleeding that can be reached by bronchoscopy (e.g. laser coagulation, local administration of adrenaline, closing the affected lobe with a bronchus blocker if necessary, etc.)

bleeding from the lung periphery:

• in the case of bleeding from the pulmonary periphery, the first-line therapy is bronchial artery embolisation This enables bleeding control to be achieved in 75 - 98 % of cases. In the absence of success, surgical intervention is indicated.
• Protection of the healthy half of the lung from aspiration by double tube

Bronchoscopic therapy:

The basic goal of therapeutic bronchoscopy is to maintain a sufficient gas exchange. Rigid bronchoscopy has proven to be most effective in this respect, as large-lumen instruments allow blood to be quickly removed from the airways. If blood clots are present, they can be frozen with the aid of a kyro probe and then extracted.

In the case of persistent peripheral haemorrhage, the most important aim is to isolate the area in question in order to prevent blood from entering the adjacent airways. This is achieved by occlusion, which uses tamponades or balloon catheters to close the affected part of the lung.

Suitable tamponades are sterile swabs with X-ray contrast strips, which are inserted into the bronchial system with forceps until the bleeding stops.

Special models have been developed for occlusion with the aid of a balloon catheter, which can be introduced via the flexible bronchoscope and additionally allow the application of therapeutic fluids through a lumen located distally of the balloon. The removal of the bronchoscope is carried out by a removable valve. It is recommended to remove both the tamponade and the balloon catheter after 72 hours at the latest, as otherwise the risk of postocclusive infections increases significantly.

In case of persistent bleeding from the central airways, the most important goal is to stop the bleeding by bronchoscopic interventional measures.

These measures include laser coagulation and argon plasma coagulation.

With the laser, visible vascular structures can be treated with pinpoint accuracy, while argon plasma coagulation allows the treatment of bleeding sources that are not orthograde to the direction of the application catheter.

Minimally invasive endovascular therapy

The method of choice in cases of massive and also recurrent pulmonary bleeding is minimally invasive endovascular bronchial artery embolization (BAE). This treatment method should be performed immediately after contrast-enhanced multi-line computed tomography and bronchoscopy. BAE reduces the systemic arterial perfusion pressure in the bronchial arteries of the affected area and thus also hemostasis.

In cases of malignant etiology of even moderate bleeding, the indication for bronchial artery embolisation should be given generously, as malignant haemoptyses have a significantly higher mortality rate (21%) than benign haemoptyses (5%).

The neurological examination often performed before the start of BAF and the monitoring of motor and sensory functions of the lower extremities during the performance of bronchial artery embolization remain controversial. One advantage, however, is certainly the fact that monitoring somatosensory evoked potentials (SSEP) allows early detection of spinal complications (such as ischemia).

When performing bronchial artery embolisation, it should be borne in mind that patients with chronic lung disease often find it difficult to tolerate the supine position and the procedure may have to be interrupted several times to expectorate blood. In the case of massive hemoptysis, if necessary, the bronchus concerned should be occluded before the actual BAE, and prior intubation of the patient is also recommended.

During the procedure, the bronchial artery branches are first angiographically located and selectively displayed. In the case of chronic inflammatory lung diseases and also in patients with cystic fibrosis, the diameter of these arteries can be extended to several millimeters.

However, active bleeding can only be detected in 3.6 - 10.8% of cases.

The arteries are often the source of haemoptysis, in

• Extension of the artery diameter to > 2 mm
• Aneurysms
• tortuous bronchial arteries
• Shunts
• hypervascularised lung parenchyma zones or
• Extravasations of contrast medium

After the pathologically altered bronchial artery has been identified and it has been ruled out that its branches supply the spinal canal (anterior spinal artery supply!) and after additional risk assessment of a possible systemic embolism in bronchial arterial pulmonary artery pulmonary artery shunts, the actual embolisation should take place. This is performed with microparticles, embolisation spirals, liquid embolisates, etc.

If haemoptyses persist, search for aberrant bronchial arteries (e.g. from the internal mammary artery) and also exclude transpleural collaterals as a source of bleeding.

If no cause for the persistence of haemoptyses can be found, a diagnosis of the pulmonary arterial tract is necessary to exclude pulmonary arterial aneurysms (e.g. Rasmussen aneurysm) or the search for pulmonary arteriovenous malformation (occurs in approx. 5% - 10.5% of cases), which can then be eliminated by embolization balloons or spirals.

Side effects of embolization:

• frequently transient chest pain
• Dysphagia
• transverse myelitis (this can occur through accidental embolization of spinal arteries) occurs in approx. 1.4% - 6.5% of cases

Bleeding control can be achieved by bronchial artery embolisation to approx. 75% - 98%.

Until the 1980s, surgical therapy was the only possible form of treatment. It was associated with high mortality. This was between 37% - 42% in emergency situations and still 7% - 18% in interval procedures.

Today, mortality in primary resections is still between 4% - 19%.

Therefore, transarterial bronchial artery embolisation has proven to be the safest and most effective treatment method for massive or recurrent pulmonary haemorrhages.

Today, surgical therapy is limited to bleeding caused by

• tuberculous caverns
• necrotizing tumor disease
• therapy-resistant aspergillomas
• traumatic or iatrogenic lung injury
• after unsuccessful bronchial artery embolization

Since the mortality rate is significantly increased in emergency operations, elective surgery is recommended with prior precise planning with regard to the cause of bleeding and the necessary extent of resection.

However, surgical treatment has its limitations in the case of extensive carcinomas with infiltration of the surrounding tissues, especially the heart, mediastinum, large vessels, trachea, etc., and in patients with advanced pulmonary fibrosis, pulmonary emphysema and severe comorbidities.

After bronchial artery embolization, 1% to 27% of patients experience recurrence in the first month after the procedure.

Within the first 4 years, the recurrence rate increases to 10% to 55%.

It has been shown that the recurrence rate is significantly lower with benign etiology of bleeding than with malignant etiology. The survival rate of recurrence-free patients with benign causes is 94% after one year, 87% after 5 years and 87% after 10 years.

In the case of malignant underlying diseases, the survival rate of recurrence-free patients is only 34% after one year.

The high recurrence rate can certainly be explained on the one hand by the fact that the therapeutic approach to bronchial artery embolisation is merely symptomatic, as there is no corresponding causal therapy to date. On the other hand, however, it is also due to the fact that the underlying lung disease is progressing and thus there is a risk of renewed haemoptysis.

Patients with aspergilloma have a particularly high recurrence and mortality rate. The risk of recurrence bleeding is between 30% - 100% and the mortality rate after bronchial artery embolisation is already about 50% in the first month. In addition to multiple bronchial artery embolizations, this clinical picture should be treated with aggressive infectiological-surgical treatment.

Surgical resection is a curative procedure by removing the source of bleeding. The long-term results with regard to a recurrence are correspondingly good at 2.2% - 3.4%. However, the high mortality rate has to be taken into account in this procedure.

1. Herold G et al (2017) Internal Medicine. Herold Publishing House. S. 346
2. Ittrich H et al (2017) Diagnosis and therapy of haemoptysis. Dtsch Ärztebl 21: 371-378
3. Schreiber J et al (2006) Differential Diagnosis of Diffuse Pulmonary Haemorrhage. Pneumology 60: 347-354
4. Schulte am Esch J et al (2011) Anaesthesia: Intensive care, emergency medicine, pain therapy. Thieme - Publisher. S. 75
5. Yoon W et al (2002) Bronchial and nonbronchial systemic artery embolization for life-threatening hemoptysis: a comprehensive review. RadioGraphics (RSNA) Radiological Society of North America 22: 1395-1409