Fig. 3
Significance of age and baseline blood flow velocity in middle cerebral artery for cerebral hyperperfusion during cardiopulmonary bypass. Blood flow velocity in the right middle cerebral artery (MCAV) was measured using transcranial Doppler sonography before cardiopulmonary bypass (CPB) and was termed MCAVbas. a Comparison of the patients’ baseline MCAV values (in cm/s), assessed before beginning of CPB, between the no-POD group and the POD group. b Association of the patients’ age with their measured MCAVbas values, with elderly patients having a reduced baseline blood flow velocity (Pearson product-moment correlation). The dashed curved lines indicate the confidence band. r = Pearson product-moment correlation coefficient, CI = confidence interval; mean ± SD (boxes) and minimum and maximum (whiskers); n = 32 (no delirium) and n = 12 (delirium); unpaired, two-tailed Student’s t-test (a); ** p < 0.01, *** p < 0.005