During general anesthesia the basic non-invasive monitoring of hemodynamic parameters (blood pressure, O2-saturation, cardiogram) is crucial. It can be enhanced to so called "extended hemodynamic monitoring" depending on the operation and patient. Frequently an invasive arterial cannula is used to provide continuous information on the blood pressure. This invasive method is very accurate and clinically established, but can be linked to adverse effects e.g. reduction of the circulation flow distal of the canulla, haematoma, infection etc. ccNexfin (Edwards Lifescience) is a finger cuff measuring the blood pressure in a non-invasive manner. It thus offers beat-to-beat information even about the extended hemodynamic parameters as cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke volume index (SVI) and stroke volume variation (SSV), if connected to the clinical platform EV1000 (Edwards Lifescience).