Fig. 3. Brain tissue damage score in neocortex and hippocampus on postoperative day 2 after cardiopulmonary bypass and deep hypothermic circulatory arrest in the desflurane and fentanyl groups. A neuronal damage score of 0 (best) represents normal structure (no damage), and a score of 5 (worst) represents severe damage (extensive infarction). Horizontal bars represent medians; n = 10 for desflurane and n = 9 for fentanyl (neurologic death occurred in 1 animal before histopathology).