Basic Bronchoscopy

Bronchoscopy is a procedure that helps to view the insides of the lungs and air passages. A bronchoscope is a thin tube (size varies from 2.8mm to 6mm) that contains thin fiber-optics that transmit light and a small lens which captures the image. The tube is sent through the nose or mouth, and moved down the throat, to reach the lungs.

Bronchoscopy is done to diagnose the cause of a lung problem. In addition to viewing the airways for any abnormalities, during the bronchoscopy several diagnostic procedures can be performed (bronchoalveolar lavage, endobronchial biopsy and transbronchial lung biopsy) which help us in diagnosing the lung problems accurately.

A bronchoscope can be flexible or rigid. In most of the cases, a flexible bronchoscope is used, but if a large object is stuck in the airway or when there is excessive bleeding in the lungs need to be controlled ,a rigid bronchoscope is used.

Complications of bronchoscopy

Bronchoscopy is a safe procedure. Complications are rare and happen in less than 1 % of the cases. Complications when they occur are usually mild and self limiting.

Procedures performed via a bronchoscope:

A) Bronchoalveolar Lavage

Bronchoalveolar lavage is a minimally invasive procedure performed during flexible bronchoscopy. In this method, normal saline is instilled into a part of the lung which is diseased, and the saline is sucked back again with the help of an aspirator. The aspirated fluid is sent for analysis. It helps to get information about the lung pathology at the level of the alveoli (small air sacs in the lungs where gas exchange takes place).

It is used to diagnose lung diseases like tuberculosis, bacterial and fungal pneumonia, hypersensitivity pneumonitis, alveolar proteinosis, and eosinophilic lung diseases.

Procedure

  • First, with the help of imaging tests,usually a CT scan of the chest, the location of lung tissue damage is identified. Next, the bronchoscope is guided to the specific location.
  • Next, about 20 to 60 ml of normal saline is injected into the bronchoscope using a handheld syringe and then slowly collected back into the syringe. The process is repeated 3-5 times so that around 300 ml of saline is instilled and aspirated.
  • The specimen obtained is sent for the test as soon as possible.
  • After finishing the procedure, the patient is kept under observation for at least 1 hour.

Safety

It is a safe procedure and can be performed even in children. In most cases, the procedure has no complications. However, in a few cases it may lead to following:

  • Transient fever
  • Transient decrease in oxygen saturation of the blood

Both the above complications are self limiting and resolve within 4 to 8 hours. People who have low oxygen levels before procedure may require supplemental oxygen during the procedure.

 B) Endobronchial biopsy

Biopsy refers to the procedure in which a small sample of the tissue is obtained and studied to find out the actual pathology. When there is an abnormality seen within the airways or the mucosa (covering) of the airway an endobronchial biopsy is performed. The tissue is collected with the help of a biopsy forceps.

Indications of biopsies

  • To diagnose any visible abnormality within the airway (lung cancer, tuberculosis etc…)
  • Biopsy of a normal looking airway also can help in diagnosing diseases like Sarcoidosis.

Method of biopsy

Endobronchial biopsy (EBB): This method is opted when the biopsy needs to be done in the larger airways. In this method, the lesion is first identified, and then the forceps are guided to the target area. The open forceps are placed at the lesion, and once a sufficient amount of tissue is engaged, the forceps is closed. After collecting the sample, the forceps are removed out through the working channels.

Safety of biopsy

Complications resulting from the biopsy procedure are rare when performed properly. However, sometimes it may lead to the complications, such as:

  • Excessive bleeding from the biopsy site
  • Hypoxemia

C) Transbronchial lung biopsy

Transbronchial lug biopsy refers to the procedure in which a small sample of the lung tissue is obtained and studied to find out the actual pathology. The tissue is collected with the help of a biopsy forceps.

Indications of biopsies

  • To diagnose abnormal lesions within the lung parenchyma

Methods of biopsy

Transbronchial biopsy (TBLB): This method is used to procure biopsy samples from the smaller, terminal airways. In this method bronchoscope is guided to the target area. The forceps are placed distal to the target area. The open forceps are further inserted until a resistance is felt. Once the resistance is felt, the forceps are closed and retracted through the working channel.

Safety of biopsy

Transbronchial lung biopsies are to be performed only by profesionals with expertise in performing such biopsies. Some complications of the procedure include:

  • Pneumothorax (accumulaton of air between the lungs and the chest wall) – Occur in 1-2% of the cases
  • Excessive bleeding from the biopsy site

Before performing the TBLB, it is a safe clinical practice to check for blood coagulation parameters. Using a fluoroscope will decrease the chance of a pneumothorax.