The purpose of the study is to evaluate the success rate using ultrasound as guidance during central venous cannulation in pediatric cardiac surgical patients.

Central venous access may be essential in pediatric patients for fluid and a blood product administration, medication, parenteral nutrition, renal replacement therapy and hemodynamic monitoring. Obtaining central venous access in pediatric patients can be challenging, failure rates in pediatric patients range from 5% to 19% with reported complication rates from 2.5% to 22%. The landmark technique has been standard approach for many years. In comparison with landmark method, in pediatric patients, the use of ultrasound is associated with an increased success rate decreased operative time, reduced number of cannulation attempts , and a decreased number of carotid artery punctures. This study is designed to evaluate the success rate, complications, time taken for successful cannulation and their correlation with cross sectional area of the vein.

Inclusion Criteria:

1. Patients requiring central venous catheterization for elective cardiac surgery.
2. Age below 15 years.

Exclusion Criteria:

1. Patient's guardian's refusal
2. Bleeding disorders
3. Clotting abnormalities (platelets count < 75,000/cumm, INR > 2)
4. Local site of infection
5. Underlying pneumothorax, pleural effusion or preoperative insertion of chest tube