Introduction
Hemoptysis refers to the expectoration of
blood originating from the lower airway or lung. Massive
hemoptysis is the form that requires urgent attention; however, the
definition of massive hemoptysis is variable in the literature and has ranged
from 100 mL/24 hrs to 1000 mL/24 hrs. The most commonly accepted definition of
massive hemoptysis is â 600 mL/24 hrs. Massive hemoptysis accounts for 1.5 to 5%
of all patients presenting with hemoptysis.
Etiology
In determining the cause of hemoptysis, other processes that could
be confused with hemoptysis, such as hematemesis or bleeding from the upper
airway, must first be eliminated. Table 18-1 outlines many
of the possible causes of hemoptysis.
In a retrospective study of Veterans Administration patients,
Santiago et al. noted that the four most commonly found causes for hemoptysis in
their patient population were cancer (29%), chronic bronchitis (23%), no identifiable
cause (22%), and TB (6%). Other identified
causes included a variety of infections, sarcoidosis, pulmonary fibrosis, and
bronchiectasis. In contrast, Hirshberg et al. performed a retrospective analysis
of an Israeli patient population. The most commonly identified causes of
hemoptysis were bronchiectasis (20%), cancer (19%),
bronchitis (18%), and pneumonia (16%). Compared to the
Santiago et al. study, unknown cause was listed only for 8% of patients and TB
for 1.4% of patients. Given that both of these studies are retrospective and
involve very different patient populations, it is difficult to compare them
directly. However, they do give an idea of the more common causes of
hemoptysis.
The circulation of the lung consists of two components–pulmonary
and bronchial. In normal patients, the pulmonary artery system is a low-pressure
system with systolic pressures of 15 to 20 mm Hg and diastolic pressures of
5–10 mm Hg. The bronchial artery arises from the aorta and thus represents
systemic pressures. Therefore, in patients with normal pulmonary artery
pressures, bleeding from the pulmonary artery only accounts for approximately 5%
of massive hemoptysis cases.
Diagnosis
The three traditional methods of evaluating the etiology of
hemoptysis include chest x-ray (CXR), CT scan, and bronchoscopy. Although CXR is traditionally the first step in evaluating
hemoptysis, it is normal in 20 to 30% of patients. For certain diagnoses such as
bronchiectasis, CT scan (high resolution) has a much
higher yield than CXR (sensitivity of 82 to 97% vs 37%).
Bronchoscopy has an overall diagnostic
yield of 26%. In patients with abnormal, but nonlocalizing CXRs, the diagnostic
yield is 34 to 55%. In patients with localizing CXRs, the yield of bronchoscopy
has been as high as 82%. In patients with moderate to severe hemoptysis,
Hirshberg et al. found that bronchoscopy was able to localize the site of
bleeding in 64 to 67% of patients. CT scan has been touted as a mode
complementary to bronchoscopy in determining the etiology of hemoptysis.
Hirshberg et al. noted that when used alone, CT scan had the higher yield (abnormal finding leading to final
diagnosis) when compared to bronchoscopy alone: 67% vs 42%. In their study, 54%
of patients with an abnormal CT scan had a positive bronchoscopy, and 38% of
patients with a normal CT scan had a positive bronchoscopy. When CT scan and bronchoscopy were used together, the diagnostic
yield was 93%.
when used alone, CT scan had the higher yield (abnormal finding leading to final
diagnosis) when compared to bronchoscopy alone: 67% vs 42%. In their study, 54%
of patients with an abnormal CT scan had a positive bronchoscopy, and 38% of
patients with a normal CT scan had a positive bronchoscopy. When CT scan and bronchoscopy were used together, the diagnostic
yield was 93%.
when used alone, CT scan had the higher yield (abnormal finding leading to final
diagnosis) when compared to bronchoscopy alone: 67% vs 42%. In their study, 54%
of patients with an abnormal CT scan had a positive bronchoscopy, and 38% of
patients with a normal CT scan had a positive bronchoscopy. When CT scan and bronchoscopy were used together, the diagnostic
yield was 93%.
TABLE CAUSES OF HEMOPTYSIS
| Infectious Pneumonia |
| Lung abscess |
| Bronchitis |
| Bronchiectasis |
| Mycetoma |
| Malignancy |
| Primary bronchogenic carcinoma |
| Extrapulmonary cancer with metastases to the lung |
| Trauma/foreign body |
| Foreign body |
| Broncholith |
| Direct trauma |
| Tracheovascular fistula |
| Cardiac/pulmonary vascular |
| Mitral stenosis |
| Pulmonary embolism/infarction |
| Pulmonary artery rupture |
| Arteriovenous malformation |
| Alveolar hemorrhage |
| Goodpasture's syndrome |
| Wegener's granulomatosis |
| Henoch–Schönlein purpura |
| Scleroderma |
| Systemic lupus erythematosus |
| Rheumatoid arthritis |
| Behçet's syndrome There is still controversy over whether to use flexible
bronchoscopy or rigid bronchoscopy in the setting of massive hemoptysis. There
are no clear data favoring one method over the other. Flexible bronchoscopy has
the advantage of better visualization of airways and the ability to navigate
into small subsegments. In addition, it can be performed at the bedside of a
patient in the ICU. However, the ability to suction blood with flexible
bronchoscopy is inferior compared to that with rigid bronchoscopy. Rigid
bronchoscopy is performed in the OR. It allows only visualization of larger
airways, but as mentioned above, the ability to clear blood from the airway is
better. In addition, more therapeutic interventions can be performed through the
rigid bronchoscope. Management In patients with nonmassive hemoptysis,
the therapy essentially involves treating the underlying cause (i.e.,
antibiotics for an infection, radiation therapy or laser therapy for an
endobronchial tumor). The more urgent need for treatment arises in patients with
massive hemoptysis.
The first priorities are airway
protection and stabilization of the patient.
The patient with massive hemoptysis usually requires intubation. If it is known
which lung contains the site of bleeding, the patient can be selectively
intubated. Selective intubation can be performed in
several manners. One method requires the use of a double-lumen ETT, which allows
for the lumen of the bleeding side to be clamped and for selective ventilation
of the nonbleeding side. The placement of the double-lumen ETT requires the help
of a physician skilled in this procedure. If the right lung is the bleeding
site, a regular ETT can be inserted into the left mainstem bronchus to allow for
selective ventilation of the left lung. Right mainstem intubation is not
recommended when the left side is bleeding because it is easy to occlude the
orifice to the right upper-lobe bronchus with the ETT and cause collapse of the
right upper lobe. Instead, if the left lung is the bleeding site, an ETT can be
placed in the trachea, and a Fogarty catheter can be inserted via a bronchoscope
into the left mainstem bronchus.
Other strategies to help minimize the
risk of aspirating blood into the nonbleeding side include positioning the
patient with the bleeding side down and the use of strong cough suppressants
(i.e., codeine). Large-bore IV access and fluid resuscitation should be started.
Any coagulopathy should be corrected. A patient with massive hemoptysis should
be observed in the ICU, even if not intubated.
Once bronchoscopy has been performed to
localize the site of bleeding, therapeutic options can
be performed through the bronchoscope, including iced saline lavage, topical
epinephrine, endobronchial tamponade, and laser photocoagulation.
Bronchial artery embolization is
frequently used to try to stop massive hemoptysis or recurrent hemoptysis (from
sources such as mycetomas). The short-term success rate of bronchial artery
embolization has been reported as between 64% and 100%. The recurrence rate of
hemoptysis after bronchial artery embolization has been noted to be between 16%
and 23%. Bronchial artery embolization may not be able to be performed if the
anterior spinal artery arises from the bronchial artery owing to the possibility
of spinal cord ischemia. The overall risk of spinal cord ischemic injury is
<1%.
Surgery is another potential therapeutic
option. To be considered a surgical candidate, a patient must be able to
tolerate a lobectomy or possibly a pneumonectomy. Surgical mortality rates that
have been reported vary between 1% and 50%. |
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