The distance between the carina and the distal margin of the right upper lobe orifice measured by computerised tomography as a guide to right‐sided double‐lumen endobronchial tube use

Abstract

The distance between the carina and the distal margin of the right upper lobe orifice measured by computerised tomography as a guide to right-sided double-lumen endobronchial tube use SummaryOur hypothesis was that the incidence of malposition of a right-sided double-lumen endobronchial tube and right upper lobe collapse may increase when the distance between the carina and the distal margin of the right upper lobe orifice is less than 23 mm, measured from a computerised tomography scan. A total of 76 patients undergoing leftsided thoracic surgery were enrolled. Patients with a measured distance of < 23 mm (n = 38) were compared with age-, sex-and body mass index-matched patients with a distance ! 23 mm (n = 38). Right-sided double-lumen endobronchial tubes were used universally. We monitored endobronchial tube malposition and incidence of right upper lobe collapse throughout surgery. There was a significantly higher incidence of bronchial cuff herniation in patients with a distance < 23 mm in both the supine position and the lateral decubitus position (p < 0.001). The incidence of intra-operative malposition in the < 23 mm group was also significantly higher than in the ! 23 mm group (31 (82%) vs 8 (21%), respectively, p < 0.001). Right upper lobe collapse was detected postoperatively in five patients (13%) in the distance < 23 mm group, compared to none in the ! 23 mm group. We recommend that the distance between the carina and the distal margin of the right upper lobe bronchus should be routinely measured on the pre-operative computerised tomography scan, and if it is < 23 mm, consideration should be given to using a left-sided endobronchial double-lumen tube in preference to a right-sided one.

Right upper lobe anatomy revisited: a computed tomography scan study

“…Nevertheless, the method we propose only requires one measure, whereas in the method previously described by Kim, three lines and two angulations need to be set to measure RSMB length. 4 We submit that our alternative method of RMSB measurement could be easily learned by thoracic anesthesiologists after a short training and should be useful in choosing the lung isolation technique. Also, according to Kim's method, 25% of our population has a RMSB \ 23 mm, which may alert anesthesiologists regarding the possibility of R-DLT malpositioning.…”

“…Twenty-five percent of our patients had a RMSB \ 23 mm, a measure that predicts R-DLT malpositioning according to Kim's study. 4 From the alternative carina-to-carina method, the mean (SD) length of the RMSB was 29.4 (4.6) mm (range: 19.1-40.8 mm). Overall, the inter-observer agreement was substantial with both methods (carina-to-carina method: ICC = 0.95; Kim's method: ICC = 0.84); the difference was however significant (P \ 0.001).…”

“…Kim et al observed a higher incidence of R-DLT malpositioning and ventilation problems as well as postoperative lung collapse when the length of RMSB was \ 23 mm on a computed tomography (CT) scan ( Figs 1A and 2). 4 The authors concluded that measurement on a thoracic CT scan is useful for clinicians to predict successful utilization of an R-DLT, and suggested that a left-sided tube should be used when the length of the RMSB is \ 23 mm. Nevertheless, the method of measurement described by Kim et al is rather complex; three lines and two angulations need to be set to obtain the measurement.…”

“…Nevertheless, the method of measurement described by Kim et al is rather complex; three lines and two angulations need to be set to obtain the measurement. 4 In addition, this method of measurement has not been submitted to inter-observer agreement studies.…”

“…1B). 4 For both methods, RMSB measures were taken on the coronal plane in the axis of the RMSB, on the frame that showed a clear tracheal carina and the largest diameter of the RMSB. With Kim's method (Fig.…”