Expert opinion on the use of fiberoptic bronchospe to check the insertion depth of the left-sided double-lumen tube.

Left-sided double-lumen tube (LDLT) is commonly used to achieve one lung isolation in most thoracic surgical procedures. Traditionally, the LDLT is blindly placed using direct or video laryngoscopy. In this brief report, we highlight the importance of using our novel insertion depth formula to predict the appropriate LDLT insertion depth and demonstrate the current evidence supporting the efficacy of the formula. Also, we will discuss two relatively new devices of LDLTs: one with an embedded camera at the distal end of the tracheal lumen and the other with a carinal cuff between the bronchial cuff and the tracheal lumen in reducing the incidence of too deep inserted LDLT. We advocate that using our novel formula and these two new devices may reduce but not eliminate the need for FOB to check the insertion depth of LDLT.