Post-Bronchoscopy and Bronchoalveolar Lavage

Your pet has had a trans-tracheal wash or bronchoscopy to try to determine the cause of the clinical signs. Bronchoscopy is a diagnostic procedure and your petsproblem will not be fixed or improved following the procedure.Only in very rare cases, such as foreign objectis a treatment for the problem performed simultaneously.

Basic health screening blood and urine tests are often recommended prior to the procedure that requires general anesthesia. Occasionally chest (thoracic) radiographs (x-rays), a computed tomographic study, or anechocardiogram is also recommended as indicated clinically. General anesthesia carries some uncommon risks, including death, esophageal strictures, aspiration pneumonia, and strokes while under anesthesia. These are extremely uncommon, and the highest quality monitoring is provided by a qualified veterinary technician.

Indications for a tracheal wash or bronchoscopy

Diseases associated with cough, shortness of breath, loud breathing sounds, or difficulty breathing can be caused by infectious, inflammatory, or neoplastic diseases of the airways. The collection of samples from the lung can be extremely informativeto determine the most likely cause for respiratory difficulty. These samples can be used to identify bacterial, fungal, or protozoal organisms and to determine the type of cells present. Occasionally, lung cancer can be diagnosed from fluid samples taken out of the lung.

Collection of airway fluid is most easily achieved by performing a tracheal wash or bronchoscopy. Sedation or anesthesia is required to perform either technique safely and effectively. The benefit of the test must always be weighed against the possible risk of the procedure.

Procedures

A tracheal wash is performed by passing a tiny plastic tube (catheter) into the airways. Through this tube a small amount of fluid can be "washed" into and out of the lung.

A transoral tracheal wash through the mouth is appropriate for use in large and small dogs or in cats. This technique requires a short period of sedation. The animal is lightly anesthetized and a sterile, relatively large tube is inserted into the trachea (windpipe). A small volume (4 to 6 mL) of sterile fluid is instilled into the airways and then aspirated (sucked back) for analysis. A small amount of fluid will remain within the lung; however, this is rapidly absorbed by the tissue and does not typically cause worsening of the animal's respiratory condition. It is common for a dog or cat to cough after having an endotracheal tube inserted and a wash performed, but this is a transient side effect.

Bronchoscopy is a more sophisticated procedure that uses a long fiber optic tube attached to a light source and camera to visualize the inside of the airways. A smaller tube within the bronchoscope allows collection of fluid from the airway. This procedure is more commonly performed in university or specialty practices. Specific indications for bronchoscopy include the following: chronic cough, coughing up blood, non-responsive respiratory conditions, unexplained pulmonary infiltrates, recurrent pneumonia.

General anesthesia is required to perform bronchoscopy to suppress coughing and airway spasm, to allow examination of the airways without inducing trauma, and to protect the endoscope. The bronchoscope can be guided into each lung lobe and will go a variable distance into the lung, depending on the size of the animal and the size of the bronchoscope. If a foreign object (stick, tooth, stone, etc.) is seen, forceps can be passed through the channel of the scope in an attempt to remove the item. After all the airways are examined, bronchoalveolar lavage (BAL) is performed by instilling a volume of fluid (10 to 20 mL) through the tube and retrieving it with aspiration for bacterial culture and cellular analysis. These results may help determine the therapy that should be provided. Any fluid that remains in the lung is gradually resorbed over 24 hours. Irregular areas on the surface of the airway or mass lesions can be evaluated by a biopsy or brush procedure. Occasionally, this can result in coughing up small amounts of blood, but typically dogs and cats do not cough excessively after recovering from the procedure.

Because bronchoscopy requires full anesthesia, not all animals are good candidates for the procedure. However, in most animals, it is a safe procedure that provides a substantial amount of information about the lung condition.

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