The central venous catheterization (central line placement) is the common procedure performed in the intensive care unit. This procedure is performed by percutaneous puncture of so called 'the central vein' and than advancement of the catheter over the guidewire (Seldinger technique). The tip of the catheter is left in the superior vena cava in the vicinity of the right atrium of the heart. Central veins are large veins in the human body passing the blood into the heart.