Predicting Optimal Insertion Depth of a Left-sided Double-Lumen Endobronchial Tube

The height-based formula of 170 - 29.5 - 5 - 1 (the insertion depth is 29.5 cm for patients who are 170 cm tall, and the insertion length is increased or decreased by 1 cm for every 5 cm increase or decrease in BH) modified by the equation of 0.1977×BH - 4.2423 is a useful tool to predict the optimal insertion depth in initially blind left-sided DLT insertion.