Influence of Two Different PEEP Niveaus and a Trendelenburg Positioning Manoeuvre on Subclavian Vein Diameter

Influence of Two Different PEEP Niveaus and a Trendelenburg Positioning Manoeuvre on Subclavian Vein Diameter as a Surrogate Parameter in Punctures of Central Veins

In 50 Patients who are undergoing a planned surgical procedure which require a central venous catheter the diameter of the subclavian vein is measured by ultrasound under 6 different conditions.

In 50 Patients who are undergoing a planned surgical procedure which require a central venous catheter the diameter of the subclavian vein is measured by ultrasound under 6 different conditions. The conditions are

1. neutral positioning, PEEP 0 cm H2O,
2. neutral positioning, PEEP 5cm H2O,
3. neutral positioning, PEEP 10cm H2O,
4. Trendelenburg positioning -20°, PEEP 0 cmH2O,
5. Trendelenburg positioning -20°, PEEP 5 cmH2O,
6. Trendelenburg positioning -20°, PEEP 10 cmH2O After these measurements a central venous catheter is used to measure the central venous pressure.

Inclusion Criteria:

• Age >18 years
• cardiosurgery or neurosurgery
• written informed consent
• ECG: inus rhythm

Exclusion Criteria:

• peacemaker
• kontraindications for PEEP
• pulmonary disease
• hemodynamically instable patients
• pregnancy
• pulmonal Hypertension
• ejection fraction < 35%
• severe valvular disease
• tricuspid insufficiency