Red Blood Cells (RBC) Transfusion Related to Central Venous O2 Saturation

The objective of this study is to estimate red blood cells (RBC) transfusion related to central venous O2 saturation (ScvO2) measurement. This prospective, randomized trial is performed in visceral, vascular and thoracic surgery units in the university hospital of Lille.

One hundred patients need to be included. Inclusion criteria are: age 18 to 99 year old, patient with central venous catheter in place and fulfilling the haemoglobin (Hb) threshold criteria for RBC transfusion according to the XXIIIth French Consensus Conference in critical care medicine recommendations.

After randomisation, patients will be eligible to receive RBC according to their level of Hb in the standard group and according to the Hb and ScvO2 in the optimization group. Patients without any disease are transfused if their Hb level is below 7g/dL; patients older than 60 years or having sepsis are transfused if their Hb level is 8g/dL or lower and cardiac patients are transfused if their Hb level is 9g/dL or lower. In the second group, transfusion is performed if and only if the ScvO2 level is les than 70% when Hb is under the same threshold levels.

The primary aim of the study is to compare the number of RBC units transfused by group (standard group or optimization group) over a period of 5 days counted from the first decision of transfusion taken post-operative. Considering the randomisation and considering the 50 % reduction of the decisions of transfusion in the group optimization, the absolute blood savings is estimated 25 % for the whole population. Secondary end points include the number of side effects associated with transfusion or when avoiding transfusion, length of hospital stay, and hospital mortality as well as major adverse events.