To Compare the In-plane and Out of Plane Ultrasound Guided Approach for Internal Jugular Vein Cannulation in the Patients Undergoing Elective Cardiac Surgery.

"In a long-axis view, the image plane is parallel to the course of the vessel (needle is in-plane). The image shows the course of the vessel across the screen and the shaft and point of the needle as it is advanced. The central venous cannulation was done in in-plane axis."

"In a short-axis view, the image plane is perpendicular to the course of the vessel and to the needle (needle is out of plane). The vessel appears as an anechoic circle on the screen of ultrasound with the needle visualized as a hyperechoic point in cross-section. The central venous cannulation was done in out of plane axis."