Con: Right-sided double-lumen endotracheal tubes should not be routinely used in thoracic surgery

Abstract

THERE IS AN ongoing debate as to whether a right-sided double-lumen tube (DLT) should be routinely used in thoracic surgery. The word routine is stressed to distinguish from special situations. The first design of the DLT in 1949 by Carlens1 was designated for left main bronchus intubation.2,3 The takeoff of the right upper lobe (RUL) near the carina made it impossible for the right mainstem bronchus to accommodate the tube without RUL occlusion. Several years later, a DLT was designed by White for right mainstem intubation. The Robertshaw4 design has a ventilating port for the RUL, and the right endobronchial cuff is S-shaped, allowing the RUL ventilation slot to ride over the RUL orifice. In the left main bronchus, the distance between the carina and takeoff of the left upper lobe orifice is adequate to accommodate the tip of the bronchial lumen without occluding the left upper lobe orifice. That distance varies between men and women and has been extensively described by Benumof et al.5 In their study, the distance was determined to be between 5 and 6 cm in women and between 6 and 8 cm in men. In the right main bronchus, the distance between the RUL orifice and the carina is short, and there is a narrow margin of safety. Although there is wide anatomic variation of the distance, most often it is between 1 and 2 cm from the carina. In some cases, the takeoff is adjacent to the orifices of the middle and lower lobes.6-8 In addition, the takeoff of the RUL orifice may often be at the level of the carina or at the trachea. Adequate ventilation requires proper positioning of the DLT with the ventilation slot opening directly into the RUL bronchial orifice. This positioning may be difficult and time-consuming to achieve and is prone to a high incidence of RUL occlusion. It often requires multiple manipulations and tube rotations until the right-sided DLT adequately aligns with the RUL orifice. Fiberoptic confirmation requires a skilled and experienced operator and does not guarantee the absence of intraoperative dislocation resulting from surgical manipulation or changes in patient position. Positioning of the RDL tube blindly, without the use of fiberoptic bronchoscopy, is unacceptable.9-14 Clinical assessment of breath sounds of the RUL is difficult to appreciate, and it is not surprising that the right-sided DLT has low popularity among practicing anesthesiologists. To avoid the problems associated with right-sided DLTs, most clinicians select left-sided DLTs for procedures on the left and right sides. Fig 1 summarizes the issues of concern when a right-sided DLT is used and why, in the author’s opinion, it should not be routinely used during thoracic surgery.