Fig. 4. Sensory function after escalating volumes of cerebral air emboli (CAE) during cardiopulmonary bypass (CPB) or sham operation (sham). Logistic regression demonstrates a relation between survival without any sensory deficits and the logarithm of CAE volumes (mean value ± 95% confidence interval) with dose–effect curves shifted significantly leftward for CPB–CAE groups (ED50= 0.2 μl; 95% confidence interval, 0.0–0.4 μl) compared with the sham–CAE groups (ED50= 0.7 μl; 95% confidence interval, 0.2–1.3 μl; P =0.04). Treatment (xenon vs. nitrogen) showed no impact on motor outcome after CPB or sham operation. Therefore, dose–effect curves for the subgroups (xenon and nitrogen groups) are not displayed.