 A catheter was introduced into the endotracheal tube through a T connector and five successive 20 mL aliquots of normal saline were flushed through the catheter, each time suctioning out the sample into the Lukens trap. 
A catheter was introduced into the endotracheal tube through a T connector and five successive 20 mL aliquots of normal saline were flushed through the catheter , each time suctioning out the sample into the Lukens trap .