Catheterization methods use the lower margin of the right third intercostal space to predict the catheter tip position; however, adjustments are often necessary. We evaluated the catheter position and surface markers of the chest and the relevant factors that affect the position and depth of the catheter tip. This single-center, cross-sectional study included 173 patients who underwent right internal jugular vein tunnel insertion with a tunneled cuffed catheter (TCC). The sternal length, intercostal width, anterior-to-posterior sternal diameter, and transverse diameter of the thorax were recorded, and the thoracic aspect ratio was calculated. The cardiothoracic ratio and position of the catheter tip were measured using chest computed tomography. The correct placement was when the catheter tip was in the upper 1/3 of the right atrium (deep group: below the correct placement; shallow group: above the correct placement). Catheter tip indices were subjected to logistic regression analyses. A receiver operating characteristic (ROC) curve was used to assess the risk and optimal cutoff of the catheter tip depth. There were significant differences in sternum length, cardiothoracic ratio, anterior-to-posterior thoracic diameter, and thoracic aspect ratio between the groups (p < 0.05). The latter three variables were influencing factors for catheter tip depth (p < 0.05). The anterior-to-posterior thoracic diameter (p = 0.003; cutoff, 22.5 cm; ROC, 0.695) and thoracic aspect ratio (p = 0.014; cutoff, 0.74; ROC, 0.632) were independent risk factors for catheter tip depth and position, respectively. The position of the TCC catheter tip was related to the sternal length, anterior-to-posterior thoracic diameter, thoracic aspect ratio, and cardiothoracic ratio.

Liu C, Zhao X, Wang H, Huang Y, Ma S, Shi Z, Duan S. Analysis of factors affecting the tip position of a tunneled cuffed catheter using the thoracic surface marker method. Ren Fail. 2025 Dec;47(1):2496435. doi: 10.1080/0886022X.2025.2496435. Epub 2025 May 6. PMID: 40329434; PMCID: PMC12057773.