Roundtable conference on tissue oxygenation in acute medicine, Brussels, Belgium, 14-16 March 1998.

* Nutritional tissue perfusion and tissue metabolic demand are heterogeneously distributed. * Oxygen diffusion occurs preferentially at the precapillary arteriolar level. * Determination of adequacy of tissue oxygenation requires local organ measurements. * While there remains considerable variability in individual RBC transfusion practices, a recent clinical trial questioned the efficacy of RBC transfusion to hemoglobin concentrations greater than 80 gm/l in patients without heart disease [63]. * RBC substitutes, including cell-free hemoglobin solutions and PFC solutions are efficacious, yet may exhibit a number of direct vascular effects.