Placement of left double-lumen endobronchial tubes with or without a stylet

This study was designed to determine if leaving a stylet in the left Bronch-Cath endobronchial tube (DLT) for the entire intubating procedure improves the accuracy of placement on the initial attempt, without introducing complications.

Sixty ASA 1-3 patients were randomized to one of two groups. In Group 1 (n = 30), the stylet was retained for the entire intubation procedure and in Group 2 (n = 30), the stylet was removed once the bronchial cuff had passed the vocal cords. In both groups, the DLT was turned 110 degrees counterclockwise and advanced until resistance was encountered. Placement was assessed by auscultation and fibreoptic bronchoscopy (FOB). After surgery, the DLT was replaced by a single-lumen endotracheal tube. The thoracic surgeon (blinded to the method of intubation, and using a FOB) assessed the appearance of the tracheobronchial mucosa.

The two groups were similar with respect to sex, height, weight, DLT size, surgeon and expertise of the laryngoscopist. When the stylet was retained, the DLT was correctly placed 60% of the time compared with 17%, if the stylet was removed, (P = 0.001). Seven out of 30 DLTs in Group 2 were initially placed into the right mainstem bronchus, (P = 0.005). The average time to confirmation of correct tube placement by FOB was increased in Group 2, (P = 0.01). Although the observed incidence of left bronchial, mucosal petechiae and erythema was greater in Group 2, this was not statistically significant, (P = 0.063).

Retaining the stylet for the entire intubation procedure allows for a more rapid, accurate placement of the DLT without increasing the incidence of tracheobronchial mucosa injury.