Utility of Syringe Based Suction Versus Channel Suction in Bronchoalveolar Lavage

Overview

Bronchoalveolar lavage (BAL) is a common technique among pulmonologists. Its goal is to collect cells from alveolar units. This is done by wedging a flexible bronchoscope in a bronchus, instilling saline, and removing the saline via suction. Two techniques are currently used for suctioning: syringe based and channel suction. The investigators concern is that channel suction creates too much force and there is collapsing of the airways which results in decreased fluid removal as well as cell sampling. The investigators propose that syringe based suctioning will not only return more of the instilled fluid but also more cells from the alveoli.

The pulmonary segment with the most disease on imaging will be the segment sampled. The scope will be wedged in the airway leading to that segment and 100mL of saline will be instilled into the selected segment and collected via the syringe based or channel based suction. Prior to unwedging, another 100mL of saline will be instilled into the same segment and will be collected using the alternative method. There will not be randomization, but the investigators will alternate which method is used first to eliminate confounding variables. All patients will receive both modalities of suctioning. The wall suction used for the channel suction will be set at 80 mm Hg. Syringe based suctioning will be performed with 20mL syringe. Total amount of fluid collected will be recorded and samples will be sent for cell count and differential as well as Gram stain and culture. Results of the two techniques will then be compared to determine which is the superior suctioning modality for BAL.