Comparison of the resistances of double-lumen endobronchial tubes

The resistance of commonly-used double-lumen endobronchial tubes were measured and a detailed comparison made. Robertshaw tubes were generally found to have a lower resistance than either the Carlens or the White tubes of equivalent size, but this was not so in every case. The White tubes had a disproportionately high resistance associated with the upper lobe orifice when compared with the resistance of the right main orifice. Theoretically this could lead to uneven ventilation of the right lung. This was not found to be the case in the right-sided Robertshaw tube.