Proper Depth of Percutaneous Central Venous Catheter via the Great Saphenous Vein for Very Low Birth Weight Infants: A Single-Center, Prospective Cohort Study

Background: A proper depth of percutaneous central venous catheter (PCVC) is very important to reduce procedural time and prevent various complications in very low birth weight (VLBW) infants who require minimal handling or have a sensitive skin. The objective of this study was to suggest a formula for faster and proper insertion of PCVC in VLBWIs to prevent unintended consequences of patients’ conditions. Methods: Prospective data of VLBW infants admitted from June 2015 to January 2018 who had PCVC inserted via the great saphenous vein within seven days after birth were analyzed. Correlations of length of inserted PCVC with body weight, body length, and postmenstrual age at the date of PCVC insertion were determined with a linear regression analysis. Using results of this analysis, a formula to determine the optimal insertion length of PCVC was derived. Coefficient of determination was used to assess how well outcomes were replicated by the formula. Results: The formula to predict the proper insertion length of PCVC via the great saphenous vein at popliteal crease level was obtained as follows: Optimal Length (cm) = 3.8 × Body Weight (kg) + 11.1. With everyday movements such as flexion and extension of the lower extremities, the mean difference in catheter tip position was 7.0 ± 3.9 mm, which was not significant enough to escalate the risk of catheter tip displacement. The rate of catheterrelated complications was as low as 4.9% in this study.