Equipment See Procedure in Percutaneous Femoral Vein Catheterization section Procedure Position the patient in 15 to 20 degrees of Trendelenburg with the head turned over the bed or table edge Mild hyperextension of the neck tenses the sternocleidomastoid muscle to localize the landmarks The medial approach uses the apex of the triangle formed by the sternal and clavicular heads of the sternocleidomastoid muscle as the entry site ( Fig 130.6 ) Catheter length can be estimated as the distance from the insertion site to the nipple line The vein is lateral to the artery and should be localized by palpation, with ultrasound, or both before puncturing the skin Using an introducer needle attached to a syringe, advance at a 45-degree angle to the skin in the caudal direction Aim toward the ipsilateral nipple Aspirate gently on the syringe as advancing; the vein should be entered at a depth of to cm If this fails, withdraw the needle slowly with constant traction on the plunger of the syringe If blood return does not signify venous entry, reattempt cannulation by advancing the needle slightly lateral to the initial attempt (do not advance the needle more medial to the ipsilateral nipple line) After obtaining blood flow, introduce the guide wire and then the catheter, as previously described Check for blood return, and secure the line with suture and tape A radiograph of the chest should be examined for line position and for pneumothorax Ultrasound guidance is the preferred method of catheter insertion into the internal jugular vein