Usefulness of Tip-to-Carina Distance as a Marker for Detecting Right Atrium Positioning of a Central Venous Catheter on Chest X-Ray

Park, Joon Min; Chung, Tae Nyoung; Kim, Min Joung; Kim, Sun Wook; Park, Yoo Seok; Chung, Sung Pil; Kim, Seung Ho

Abstract

PURPOSE: Our goal was to check the effect of physique on tip-to-carina (TC) distance for detecting the right atrium (RA) position of a central venous catheter tip, and to determine the optimal cut-off value for TC distance.
METHODS
We did a retrospective review of patients who were given chest computed tomography within 12 hours after central venous catheterization (CVC) between September 2005 and February 2009. We used electronic medical records (EMR) and a picture archiving communication system (PACS). TC/height ratio and TC/thoracic width ratio were used as height and thoracic width corrected TC distances. We developed receiver operating characteristic (ROC) curves for TC distance, TC/height and TC/thoracic width, and compared the area under curves (AUCs) of each. An optimal cut-off value for TC distance was obtained using ROC curves.
RESULTS
A total of 88 patients were enrolled in our study to determine the optimal cut-off value for TC distance. Of the 88, records for 64 included height, which was required for comparing TC with height and thoracic width corrected TC. AUCs of TC, TC/height, and TC/thoracic width were, respectively, 0.966, 0.962, 0.970. There was no statistically significant differences between them. The cut-off value for TC distance for detecting RA positioning of a CVC is 30 mm (Sensitivity = 100%, Specificity = 85.1%).
CONCLUSION
TC distance is a useful marker for detecting RA positioning of a CVC regardless of the patient's height and thoracic width. We suggest 30 mm as the optimal cutoff value for TC distance.