Fig. 5. Central venous pressure (CVP), mean arterial pressure (MAP), and intestinal microvascular oxygen partial pressure (μPo²) during extreme normovolemic hemodilution in the rat. Stepwise hemodilution was performed with pasteurized protein solution. After hemodilution, a bolus dose of 2.5 ml pasteurized protein solution was infused over 10 min. Data represent mean ± SD (n = 4). ○μPo²:P < 0.05 versus  baseline; *MAP:P < 0.05 versus  baseline. MAP and μPo²decreased significantly, whereas CVP did not change throughout the experiment, indicating that isovolemia was maintained. Fluid challenge decreased hematocrit (Ht) from 8% to 6% but did not result in a significant change in the other parameters.