Central venous access is often necessary in order to adequately resuscitate a patient with large volumes of fluid or blood products, monitor intravascular volume, perform hemodialysis, administer parenteral nutrition, and administer antibiotics. Internal jugular and subclavian veins are most commonly used. When access is obtained via the internal jugular (IJ) vein, placement of the catheter on the patient’s right side is best (except in cardiac transplant patients; see Chapter 59) secondary to the vein’s superficial position and larger size in that location. Overall, the IJ vein is the preferred site for dialysis access, allows for easier control of arterial puncture, and is less likely to cause central stenosis. The subclavian vein is associated with the lowest risk for infection, but it does come with a higher risk for pneumothorax and central stenosis. Femoral venous access should be avoided unless no other access is available or it is an emergency situation. Placement of central access in the groin has the highest risk of infection and deep venous thrombosis.