Venous cutdown is an emergency procedure in which the vein is exposed surgically and then a cannula is inserted into the vein under direct vision. It is used for venous access in cases of trauma, and hypovolemic shock when the use of a peripheral venous catheter is either difficult or impossible. The great saphenous vein is most commonly used. This procedure has fallen out of favor with the development of safer techniques for central venous catheterization such as the Seldinger technique, the modified Seldinger technique, intraosseous infusion, as well as the use of ultrasound guidance for placement of central venous catheters without using the cutdown technique.