Mixed venous oxygen saturation (SvO2) is an important parameter in the management of patient during liver transplantation surgery especially during portal vein clamping. The only way to measure it is to use a pulmonary artery catheter. If the authors can show a positive relationship between invasive SvO2 measurement and noninvasive jugular venous oxygen saturation (SjvO2) measurement with VO 100 medical device, it will possible to use SjvO2 as a noninvasive surrogate of SvO2 in patients during liver transplantation surgery.

SvO2 measures mixed venous oxygen saturation from the lower and upper half of the body. To be measured, Sv02 requires a central venous catheter. SvO2 gives knowledge about the balance between the delivery of oxygen and oxygen consumption in the body. Interest in SvO2 monitoring in anesthesia and critical care has been debated. However, SvO2 is still recommended as a major hemodynamic target of early resuscitation of critically ill patients. SvO2 measurement through pulmonary artery catheter is accompanied with morbidity due to its invasiveness. During liver transplantation surgery, measurement of SvO2 is required to adequately manage hemodynamics of the patient, especially during portal venous clamping.

VO 100 medical device from Mespere LifeSciences allows a non-invasive measurement of SjvO2 using the NIRS technique. Jugular venous oxygen saturation (SjvO2) is a measurement of the amount of oxygen left in the venous system after the brain has removed the oxygen that it needs.

On the same principle that a positive relationship between ScvO2 and SvO2 has been shown, what the investigators are trying to do is to show a positive relationship between SjvO2 and SvO2 in order to possibly use in the future SjvO2 measured by VO 100 as a noninvasive surrogate of SvO2 during liver transplantation surgery.

Inclusion Criteria:

• Adult patients routinely equipped with a pulmonary artery catheter just before liver transplantation surgery allowing SvO2 measurement.

Exclusion Criteria:

• Adult patients not equipped with pulmonary artery catheter for liver transplantation surgery.

Adult patients undergoing liver transplantation surgery for whom measurement of SvO2 is required especially during portal vein clamping.