Reliability of auscultation in positioning of double-lumen endobronchial tubes.

Auscultation is a well-established technique to confirm the position of double-lumen endobronchial tubes (DLTs). However, some authors have recommended that fibreoptic bronchoscopy (FOB) is also indicated. The aims of this study were to determine first if bronchoscopy after blind placement of DLTs improved positioning; and second if preoperative bronchoscopy could detect difficult intubation. Twenty-four patients undergoing aortic or lung surgery were studied. After intubation with a single-lumen tube, an initial FOB was performed by an independent observer to check the airway anatomy. Then, the single-lumen tube was replaced by a DLT using a classical "blind" intubation method. Subsequent FOB was performed first by the independent observer to record the DLT position and next by the investigators for improvement or correction of their positioning under visual control. Fibreoptic bronchoscopy after blind placement of DLTs resulted in repositioning 78% left-sided DLTs and 83% right-sided DLTs. Preoperative bronchoscopy did not always detect an airway abnormality which might lead to difficult positioning of the DLTs. In conclusion, auscultation is an unreliable method of confirming the position of DLTs and should be followed by fibreoptic bronchoscopy.