The angle range of leg abduction with external hip rotation which can minimize femoral artery and vein overlap in pediatric patients.

Background: Since the femoral artery frequently overlaps the femoral vein, femoral central venous catheterization carries the risk of arterial puncture in pediatric patients.

Aims: We evaluated the angle range of leg abduction with external hip rotation to minimize the overlap between the femoral artery and vein in pediatric patients undergoing general anesthesia.

Methods: Eighty-two pediatric patients who underwent elective surgery with general anesthesia were enrolled in this study. Using ultrasonography, patients were divided into groups N (patients with non-overlap) and O (patients with continuing overlap) based on the presence of non-overlap range between the femoral artery and vein. The range minimizing the overlap was defined as the range without overlap in group N and as the range presenting the overlap that was less-than-half of the radius of the femoral vein in group O. By increasing the angle of leg abduction with external hip rotation, the starting and ending angles minimizing the overlap were found using ultrasonographic images.

Results: The angle range of leg abduction with external hip rotation minimizing the overlap between the femoral artery and vein was defined as the range from the maximum 99% confidence interval of starting angles to the minimum 99% confidence interval of ending angles, which was between 45° and 65° in group N and between 48° and 58° in group O, respectively.

Conclusion: Positioning patients in a range of 48° and 58° leg abduction with external hip rotation can minimize the overlap between the femoral artery and vein. However, the clinical usefulness of this positioning for femoral venous catheterization remains to be seen.