There is no recommendation for the management of the positive end-expiratory pressure (PEEP) during setting of a central venous catheter (CVC) in a ventilated patient. Several non-randomized studies have investigated the cross-sectional area (AST) ultrasound minor axis for different pressure levels by evaluating a single vessel every time or by not displaying the right or left side in the evaluation. Another study showed that there could be unpredictable size differences between the 2 subclavian veins.~In ventilated patient, the PEEP, which is intrathoracic, will result in a decrease of venous return and thus possibly a superior vena cava dilation, located outside the pleura, depending on their capacitance. Different pressure levels showed an increase of AST with the increase of intra-thoracic pressure on certain veins, in a heterogeneous and not randomized manner.~The primary purpose of the study is to measure the effect of PEEP (0, 5, 10 or 15 cm H2O) and the patient's position (supine or Trendelenburg strict -15-20 °) on the cross-sectional area of the jugular and subclavian veins.
There is no recommendation for the management of the positive end-expiratory pressure (PEEP) during setting of a central venous catheter (CVC) in a ventilated patient. Several non-randomized studies have investigated the cross-sectional area (AST) ultrasound minor axis for different pressure levels by evaluating a single vessel every time or by not displaying the right or left side in the evaluation. Another study showed that there could be unpredictable size differences between the 2 subclavian veins.~In ventilated patient, the PEEP, which is intrathoracic, will result in a decrease of venous return and thus possibly a superior vena cava dilation, located outside the pleura, depending on their capacitance. Different pressure levels showed an increase of AST with the increase of intra-thoracic pressure on certain veins, in a heterogeneous and not randomized manner.~The primary purpose of the study is to measure the effect of PEEP (0, 5, 10 or 15 cm H2O) and the patient's position (supine or Trendelenburg strict -15-20 °) on the cross-sectional area of the jugular and subclavian veins.