Echocardiography With Bubble Test for Tip Location of Central Venous Catheters

Measure of time between injection of echographic contrast in the distal lumen of a central venous catheter, inserted via supra/infra clavicular right veins, and visualization, using transthoracic echocardiography, of micro bubbles in right atrium with the catheter tip positioned under transesophageal ultrasound control in four different positions: right atrium, cavo-atrial junction (CAJ), at 4 centimeters proximal to CAJ, in superior vena cava and at 8 centimeters proximal to CAJ