[Analysis of the association between double-lumen endobronchial tube and inner diameter of the left main bronchus].

OBJECTIVE: To investigate the association of the left double-lumen endobronchial tube (DLT) and the inner diameter of the left main bronchus.

METHODS: Totally 100 adult patients who required intubation of a left-sided DLT during anesthesia for elective thoracic surgery were randomly enrolled in this study. All the participants underwent a preoperative chest CT scan by a spiral CT scanner. The diameters of the trachea and left main bronchus were measured with three-dimensional image reconstruction technique. All the measurements were performed using the electronic calipers of the spiral CT scanner and the left-sided DLT (Portex SIMS, USA) of the sizes 41Fr, 39Fr, 37Fr, and 35Fr were selected, being predicted according to the inner diameter of the left main bronchus. The placement of DLT was performed after anesthesia induction, and a DLT of a smaller size was selected if the bronchial end of the DLT failed to enter the left main bronchus after two attempts. The trachea and left main bronchus were examined for injury and other complications with postoperative fibreoptic bronchoscopy (FOB).

RESULTS: All the 100 patients were intubated with DLT of appropriate sizes and satisfactory lung isolation was achieved. Postoperative complications of the trachea and bronchus were observed in none of the patients with FOB examination. The appropriate size of DLT is correlated with the left main bronchial diameter (correlation coefficient r=0.7346).

CONCLUSION: Clinically, the size of DLT can be determined in accordance with the inner diameter of the left main bronchea.