 Fiberoptic bronchoscopy Introduction: The introduction of the flexible fiberoptic bronchoscope more than 30 years ago provided the opportunity for pulmonologists and thoracic surgeons to diagnose conditions previously beyond the range and capability of the rigid bronchoscope. The advent of the fiberoptic bronchoscope revolutionized the practice of pulmonary medicine. Its small diameter, flexible tip, large biopsy and suctioning channel, and accessory diagnostic tools (i.e. biopsy forceps, brushes and needles) allowed the bronchoscopist to reach farther out into the bronchial tree to establish diagnoses in a wide variety of clinical situations at the bedside as well as in the outpatient arena (Figure 1).
Additionally, the effectiveness of local anesthesia and improved intravenous sedation methods have improved patient acceptance of this procedure in an outpatient setting. Indications for outpatient bronchoscopy Evaluation of new or chronic cough Prior to considering diagnostic bronchoscopy for chronic cough, the workup should include methacholine challenge for reactive airway disease, esophageal pH monitoring or endoscopy for reflux symptoms, and careful ear, nose and throat examination. Although bronchoscopy should not be part of the initial evaluation of cough, the procedure can be useful in carefully selected patients in whom other diagnostic efforts and empiric treatment have failed. Benign, as well as malignant, tumors of the airway may present with cough as the sole symptom despite normal chest roentgenogram and CT scans. Thus, in carefully selected patients with cough, fiberoptic bronchoscopy can be very helpful in excluding an occult lesion responsible for the cough. Evaluation of hemoptysis A useful rule in the adult population is that any new episode of hemoptysis requires bronchoscopic evaluation unless another cause is apparent, such as mitral stenosis or pneumonia, to exclude a malignant lesion of the lung. One should recall that bronchogenic carcinoma is found in approximately 30 percent of patients who undergo evaluation for hemoptysis, especially in those who smoke, have an abnormal chest roentgenogram and are older than 40. The optimal timing for bronchoscopy in patients with non-urgent bleeding remains controversial. Although it would appear that prompt bronchoscopy in the presence of hemoptysis would be helpful in localizing the site of bleeding, in practice it has not been demonstrated that the diagnostic yield can be improved by performing bronchoscopy immediately after the onset of bleeding. Paradoxically, the presence of clot may obscure the bronchoscopist's vision, often requiring repeat bronchoscopy at a later date. Patients with massive hemoptysis require immediate bronchoscopy. It remains debatable in these patients whether bronchoscopy is best performed using the rigid bronchoscope or the flexible bronchoscope. At AGH, we use both instruments in patients with massive bleeding in the operating room under controlled conditions to facilitate localization of the bleeding site. We believe a team approach involving a pulmonologist, thoracic surgeon and skilled anesthesiologist best serves the needs of these critically ill patients. In adult patients with hemoptysis and a normal chest roentgenogram, bronchogenic carcinoma is found to be the cause of hemoptysis approximately 10 percent of the time. Bronchoscopy need not be performed in patients with an obvious cause of hemoptysis such as pneumonia or in patients in whom alveolar hemorrhage is present, as the diagnostic yield of bronchoscopy is extremely low in these clinical situations. Evaluation of the abnormal chest
roentgenogram
In patients with community-acquired pneumonia, bronchoscopy is not warranted unless resolution of the radiographic abnormality does not occur or symptoms persist, suggesting the presence of another diagnosis. Bronchoscopy can be quite helpful in the management of patients with lung abscesses who fail to improve on antibiotics alone. At Allegheny General Hospital, we have used fiberoptic bronchoscopy to successfully establish drainage for lung abscesses. Additionally, endobronchial obstruction (sometimes from malignant etiologies) as the cause of the lung abscess can be ruled out by bronchoscopy. Bronchoscopic procedures: The bronchoscopist has a large armamentarium of procedures available to help establish a specific diagnosis (Table 1).
Bronchial and transbronchial lung biopsy
However, several factors affect the yield in peripherally localized lesions. If the tumor resides in a patient's bronchus, as suggested by CT scans, the diagnostic yield is high. The diagnostic yield is also acceptable for lesions that are located in the mid-lung fields and larger than 2 centimeters in diameter. The diagnostic yield reduces significantly for smaller lesions in the peripheral regions of the lung parenchyma, especially when they are located in the upper lobes. Even if malignancy of a peripheral lesion is established by other diagnostic methods, e.g. transthoracic CT-directed needle aspirate, fiberoptic bronchoscopy is indicated prior to or at the time of anticipated surgical resection to ensure that the lesion is completely resectable. In addition to its usefulness in diagnosing carcinoma of the lung, transbronchial lung biopsies have proven helpful in the diagnosis of several diffuse lung diseases. The most amendable diffuse lung diseases diagnosed by this technique are those processes that are located in the peribronchial tissue including sarcoidosis and lymphangitic carcinomatosis. Other diseases amendable to diagnosis by this technique include bronchiolitis obliterans with organizing pneumonia (BOOP), cytotoxic-induced lung disease, eosinophilic pneumonia and eosinophilic granuloma. Transbronchoscopic lung biopsy in the diagnosis of idiopathic pulmonary fibrosis, in my view, is not warranted. No distinguishing histologic features can be found in the tissue obtained by this technique, and pathologic tissue obtained by video-assisted thoracic surgical biopsy is far superior in this regard. Transbronchial bronchoscopic lung biopsy can be very useful in diagnosing pulmonary disease in immunocompromised patients. Fungal infections such as aspergillosis, and viral infections such as cytomegalovirus, can be diagnosed using the transbronchial lung biopsy technique. Finally, patients with miliary tuberculosis may be diagnosed using transbronchial lung biopsies. Major complications of transbronchial lung biopsies include pneumothorax and hemorrhage. These generally occur in less than 1 percent of cases and can be avoided by careful patient selection and proper technique. Protected bronchial brush and
bronchoalveolar lavage (BAL) BAL has also been used to diagnose specific interstitial lung diseases as well as pulmonary malignancies. BAL is performed by lavaging the involved segment of lung with 100 to 120 ml of saline, generally recovering 50 percent of the fluid for analysis. It is a safe technique, even in critically ill patients, and can also be performed in thrombocytopenic subjects. BAL alone may provide the diagnosis in a few interstitial diseases including eosinophilic pneumonia, pulmonary hemorrhage and lymphangitic carcinoma; however, its overall usefulness in interstitial diseases is limited. Although increased eosinophil count or neutrophil count in BAL fluid in patients with idiopathic pulmonary fibrosis suggests a poor response to treatment with steroids, there is no evidence that repeated BAL for surveillance affects clinical decisions or improves outcome. Thus, with the exception of a few interstitial diseases, BAL should be considered an investigational tool and not used as a guide in determining the degree of alveolitis present in patients with interstitial lung disease. Transbronchial needle aspiration At Allegheny General Hospital, our diagnostic yield has been enhanced by working closely with our cytopathologists, who are among the most accomplished in North America. As cytologic specimens are immediately interpreted in the bronchoscopy suite, multiple aspirations can be performed in a timely fashion until a specific diagnosis is established. Transbronchial needle aspiration can be useful in staging the extent of disease in patients with known or suspected lung carcinoma. Peri- tracheal and subcarinal lymph nodes are easily sampled, as they characteristically lie in proximity to the trachea. Additionally, TBNA can be useful in diagnosing visible submucosal lesions as well as peripheral lung lesions under fluoroscopic guidance. Finally, TBNA has been helpful in establishing benign causes of mediastinal adenopathy, for example, in patients with sarcoidosis. Conclusions: In summary, fiberoptic bronchoscopy can be very helpful in a wide variety of lung disorders. Close cooperation between the pulmonologist, thoracic surgeon and pathologist enhances the ability of the clinician to establish precise diagnoses in a prompt and safe manner. Suggested reading Prakash, Vdaya B.S. Bronchoscopy in Pulmonary and Critical Care Medicine. Mosby Volume 1 Part F #5 1-14, 1998. Wang, Kopen. Transbronchial Needle Aspiration and Percutaneous Needle Aspiration for Staging and Diagnosis of Lung Cancer. Clin Chest Med. 16:535-552, 1995. Meduri GV, Iski V. Role of Bronchoalveolar Lavage in Diagnosing Non-opportunistic Bacterial Pneumonia. Chest. 100:179-190, 1991. Dweik R, Stoller J. Role of Bronchoscopy in Massive Hemoptysis. Clin Chest Med. 20:89-106, 1999. Arroliga A, Matthay R. The Role of Bronchoscopy in Lung Cancer. Clin Chest Med. 14:87-98, 1993. HOME
| WHAT'S NEW | PROGRAMS & SERVICES
| PHYSICIAN NEWSLETTER |
