Fig. 3. (Top ) Hemoglobin–oxygen delivery (Do²) relationship in the two halothane groups during stepwise hemodilution. Stars = halothane 1.0 MAC group;squares = halothane 1.5 MAC group. (Bottom ) Hemoglobin–Do²relationship in the two ketamine groups during stepwise hemodilution. Stars = ketamine low-dose group;squares = ketamine high-dose group.