Figure 1. Concentration (mean +/- SD) of lactate in the blood (circle) and in cerebrospinal fluid (CSF; triangle) three groups of patients: those with normal body temperature but without distal femoral bypass (solid line; n = 6); those with normal body temperature and distal femoral bypass (dotted line; n = 7); and those with hypothermia and distal femoral bypass (dashed line; n = 8). The increase in blood and CSF lactate with release of the proximal aortic cross clamp (AXC off) and, later, release of the distal clamp (all AXC off) was significant compared with baseline (BL) in all groups (P < 0.001 to 0.05). The difference in blood and CSF lactate among groups was also significant:*P < 0.01 between blood lactate concentrations and CSF lactate in the two normothermic groups;**P < 0.001 between the CSF lactate concentrations in the hypothermic group and CSF lactate in the two normothermic groups (probability value determined by analysis of variance).