Combined Use of Ultrasound and Reverse Trendelenburg Position to Facilitate Cannulation of a Femoral Vein Completely Overlapped by the Femoral Artery

To the Editor: When the femoral artery totally overlaps the femoral vein, inadvertent femoral artery puncture may be inevitable when attempting to cannulate the femoral vein using traditional external landmarks. We describe a case in which successful femoral vein cannulation was achieved without arterial puncture, despite complete overlap of the vein by the femoral artery. Central venous cannulation via the femoral vein was planned in a 3-mo-old infant (7 kg, male) undergoing excision of a lymphangioma on the forehead. After induction of general anesthesia, ultrasound examination of both femoral vessels just distal to the inguinal crease (Sonos 4500®, Philips, MA, equipped with a 5 MHz linear probe) showed that both femoral veins were completely overlapped by the respective femoral arteries (Fig. 1a). Reverse Trendelenburg position and inguinal compression were used to increase the femoral vein cross-sectional area after which the femoral vein cross-sectional area increased from 0.035 cm2 to 0.128 cm2, and the degree of overlap of the femoral vein by the femoral artery was reduced considerably (Fig. 1b). Real-time ultrasound-guided femoral vein catheterization was performed successfully just lateral to the femoral artery on the first attempt without arterial puncture (Fig. 1c).Figure 1.: Ultrasonographic findings of the femoral vein showing the increase in cross-sectional area with inguinal compression in reverse Trendelenburg position (b) from the baseline (a). When the needle (black arrow) entered just lateral to the artery on the ultrasonographic image, the vessel wall was observed to be somewhat collapsed (c). FA = femoral artery; FV = femoral vein.Reverse Trendelenburg position has been reported to increase the diameter of the femoral vein in children and inguinal compression has been reported to increase its size in adults.1,2 In this case, combined use of inguinal compression and reverse Trendelenburg position along with ultrasound guidance allowed us to reduce the risk of arterial puncture facilitating femoral vein cannulation in a child in whom the femoral artery completely overlapped the femoral vein.3 Eun Ha Suk, MD, PhD Department of Anesthesiology and Pain Medicine Asan Medical Center Ulsan university, College of Medicine Seoul, Korea Dong Hun Kim, MD, PhD Department of Radiology Soonchunhyang University College of Medicine Bucheon, Korea [email protected]