Evaluation for the range of smallest leg angulation with femoral artery and vein overlap with femoral central catheterization in pediatrics.

In pediatrics, femoral vein catheterization often overlaps with the femoral artery.

In this case, the risk of artery puncture is high, vein collapse when artery puncture 2nd, 3rd times exceeds the success rate of catheterization becomes low. In previous study, comparing 0, 30, and 60 degrees with frog leg position, there was a study that the overlap was the smallest at 60 degrees. A previous study was a simple frog leg position and a study in fragmented predetermined angles. On a continuous measurement, we planned the study under the assumption that there is a more definite range of optimal angulation.

Ultrasound probe in the state of Inguinal crease, we find a part without bifurcation of femoral artery and femoral vein in frog leg position(external rotation + flexion increase). Increase the leg angle and check the vein and arterie relations.

Inclusion Criteria:

1. Pediatric patients younger than 3 years
2. ASA class 1-3
3. Patients scheduled for elective surgery.
4. If the patient's guardian can understand and write the contents of the agreement.

Exclusion Criteria:

1. A patient with previous history of dislocation of the hip.
2. Hip joints with limited hip movement.
3. A patient with vascular malformation of the femoral vein
4. Emergency surgery
5. Hemodynamic unstable patient
6. If the patient's guardian cannot understand and write the contents of the agreement.

Patients scheduled for elective surgery.