The Incidence of Tracheal Bronchus in Thoracic Surgery Patients and Its Implication for Lung Isolation: A Retrospective Cohort Study

Abstract

To investigate the incidence of tracheal bronchus (TB) and explore its implication for lung isolation. Retrospective cohort study. Academic, tertiary care hospital. The study comprised 7,102 thoracic patients with- one lung ventilation. No intervention. Two independent anesthesiologists reviewed the computed tomography images to identify the presence of a TB, and their results were confirmed by a radiologist. The clinical data of patients with a TB were obtained from the electronic medical record. Data regarding the device used to provide lung isolation, preoperative oxygen saturation (SpO2), and intraoperative SpO2 during one- lung ventilation were obtained from the electronic anesthesia record. The incidence of TB was 1.08% (77 of 7,102). The TB arose from the right side of the trachea in all 77 patients, including 70 type Ⅲ TBs and 7 type Ⅱ TBs. Left- and right-sided double-lumen tubes (DLTs) were used in 54 and 23 patients, respectively. For patients with a left-sided DLT, the median SpO2 and incidence of hypoxemia (SpO2 <90%) were 97% and 6 of 54 (11.1%), respectively. For patients with a right DLT, the median SpO2 and incidence of hypoxemia were 95% and 7 of 20 (35.0%), respectively. There were significant differences in the mean SpO2 and the incidence of hypoxemia between patients intubated with left- and right-sided DLTs (p = 0.014 and p = 0.016, respectively). Preoperative diagnosis of TB is important when lung isolation is needed. The left-sided DLT can be used for most patients with a TB.