Tracheal wash or bronchoalveolar lavage – does it matter for diagnosing respiratory disease?

Both TW and BAL are commonly performed procedures to help diagnose a variety of respiratory conditions. TW can be performed transcutaneously or via an endoscope. The transcutaneous method should be used if bacterial culture is the main requirement since this method carries the lowest risk of contamination with nasopharyngeal flora. It is an invasive technique and therefore carries associated risks. Transendoscopic TW allows visual inspection of the upper respiratory tract as well as sample collection. Guarded catheters are available to decrease the risk of nasopharyngeal contamination. BAL can also be performed via an endoscope or ‘blind’ using a BAL tube. Endoscopy allows visual examination of the respiratory tract and enables guided placement of the sampling catheter to the affected area, if the disease process is localised. ‘Blind’ BAL will usually only sample the right caudodorsal lung field but can be performed with minimal equipment and expense. Instructions on how to perform these procedures will be presented ...