IRCT20210905052379N1 IRCT 2022-01-22 Iran University of Medical Sciences Central venous cannulation under ultrasound guidance Comparison between internal jugular central venous cannulation under ultrasound guidance and anatomical landmark method in pediatric3 months up to 6 years- randomized clinical trial 2021-09-23 anticipated 120 Complete https://irct.ir/trial/58539 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Screening, Randomization description: Block randomization will be done using seal enveloped software. The list of blocks will be written and numbers will be assigned to them (AABB (1) - ABAB (2) -ABBA (3) -BBAA (4) - BABA (5) - BAAB (6)), then random numbers between one and six ( For example, 1 4 5, etc.) will be select and finally the treatment allocation list based on previous random numbers (AABB, BBAA, BABA, etc.) will be specified. 4 cardiac disease. Intervention 1: After induction of anesthesia and sterilization, and by using an ultrasound device and movement of the probe over the carotid artery and the adjacent jugular vein, the location of the vein is confirmed. The catheter is then inserted. Intervention 2: In the anatomical landmark control group, after induction of anesthesia, a catheter is placed at the apex of the triangle, which consists of two parts of the sternocleidomastoid muscle and the right clavicle, according to the anatomical position of the central vein. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is No decision has been made yet