Transfusion of erythrocyte concentrates produces a variable increment on cerebral oxygenation in patients with severe traumatic brain injury: a preliminary study.

Abstract

To investigate the long-term influence of erythrocyte transfusion on cerebral oxygenation in patients with severe traumatic brain injury. Prospective and observational study. Neurotrauma intensive care unit of trauma center level I. Sixty consecutive, hemodynamically stable patients with severe traumatic brain injury, pretransfusion hemoglobin<100g/l, non-bleeding and monitored through intracranial pressure and brain tissue partial pressure of oxygen (PtiO(2)) catheters were included. Transfusion of 1-2 units of red blood cells. Ten sets of variables (pretransfusion, end of transfusion, and 1, 2, 3, 4, 5, 6, 12 and 24h after transfusion) were recorded, including: PtiO(2), cerebral perfusion pressure (CPP), end-tidal CO(2), peripheral saturation of oxygen, temperature, hemoglobin, lactate and PaO(2)/FiO(2) ratio. Transfusion was associated with an increase in PtiO(2) during a 6-h period, with a peak at 3h (26.2%; p=0.0001) in 78.3% of the patients. No relationship was observed between PtiO(2), CPP and hemoglobin increments. The relative increment in PtiO(2) at hour 3 was only correlated with baseline PtiO(2) (r(2) 0.166; p=0.001). All of the patients with basal PtiO(2)<15mmHg showed an increment in PtiO(2) versus 74.5% of patients with basal PtiO(2)>or=15mmHg (p<0.01, hour 3). Erythrocyte transfusion is associated with a variable and prolonged increment of cerebral tissue oxygenation in anemic patients with severe traumatic brain injury. Low baseline PtiO(2) levels (<15mmHg) could define those patients who benefit the most from erythrocyte transfusion.