The patient should be placed into a Trendelenburg position for central venous catheter placement. Trendelenburg means that the patient's head is the lowest point of the body, which reduces the risk of air embolism traveling to the brain. Additionally, it causes the vessel to become distended, which makes insertion easier. Prone (face down), Fowler's (head/back at 45-60°) and high Fowler's (head/back at 80-90°) would be inappropriate for central venous catheter placement as accidental air embolism would rise to the brain.