Confirmation of the Relation between Femoral Artery and Vein for Central Venous Cannulation: A Prospective Investigation Using Ultrasound

ABSTRACT

PURPOSE: Femoral vein catheterization is often performed using a landmark technique, despite the recommended method of using ultrasound guidance. Although the landmark-based procedure is a well-known, widely adopted method to date, there are insufficient studies validating the effectiveness of this method. Hence, the purpose of this study was to confirm the relationship between femoral artery and vein using an ultrasound, as well as to validate the effectiveness of the femoral vein catheterization method using the landmark technique. METHODS: This was a prospective, repeated measurement study. Using an ultrasound with a 10 MHz transducer, the femoral vein cross-sectional areas on the right side were saved at a distance of 1, 2, 3, and 4 cm from the inguinal ligament with supine and hip abduction-external rotation positions. The width of the femoral vessels, center-to-center distance between the femoral artery and vein(horizontal distance between the center of the femoral artery and vein) and width of exposed femoral vein (not posterior to femoral artery) were measured. RESULTS: The width of the femoral vein, the center-to-center distance between the femoral artery and vein, as well as the width of the exposed femoral vein were significantly decreased as the distance from the inguinal ligament was increased, regardless of the posture change (p<0.001). However, at a distance of 1 cm from the inguinal ligament, only 5.4% of the femoral veins were exposed without disturbance of the femoral artery, and there were also a few cases in which the femoral veins were not exposed at all. CONCLUSION: It appears that an ultrasound-guided femoral vein catheterization is recommended over the conventional landmark technique.