Combined monitoring of rSO₂ and SSEP is routinely performed during cardiopulmonary bypass (CPB), but it is not sensitive enough to detect focal lesions of the brain. Thus, we assessed whether simultaneous measurement of S-100β is able to enhance diagnostic sensitivity or not. Between September 1999 and February 2000, serial measurement of plasma levels of S-100β and SSEP and rSO₂ monitoring during CPB were simultaneously performed in 26 consecutive patients (19 men and 7 women). Ages ranged from 46 to 85 (mean 67±10 years). Neurological complications developed in 5 (19.2%). Among those patients, hemiplegia developed in 2, and dementia, temporary convulsion, and deep coma in 1 each. Three of them showed abnormally low rSO₂ levels during surgery, but no patient showed abnormal change in SSEP waves after surgery. There was no significant difference in S-100β level 1h after CPB between patients associated with or without neurological complications (1.98±0.48 vs. 1.89±1.65), however, its level 24h after CPB remained significantly higher in patients with neurological complications (1.01±1.14 vs. 0.22±0.24). S-100β level 24h after CPB appears to improve diagnostic sensitivity for detecting such focal brain damage lesions as those in which SSEP or rSO₂ are not efficient enough to make a diagnosis. However, further study is required to evaluate how fast it can differentiate patients with and without brain damage.

A 67-year-old woman had left lateral chest pain. CT scan and digital subtraction angiography revealed coarctation of the abdominal aorta just distal from the renal artery and a fusiform aneurysm of the descending thoracic aorta with a maximum diameter of 60mm. The meandering mesenteric artery was significantly dilated as a collateral vessel from the superior mesenteric artery to the inferior mesenteric artery. Aortitis syndrome was suspected from the angiographic findings although inflammatory changes in laboratory data were not observed. She underwent aneurysmectomy followed by prosthetic graft replacement of the descending thoracic aorta under femoro-femoral bypass and an extraanatomical bypass grafting from the replaced graft to the abdominal aorta proximal to the aortic bifurcation via the retroperitoneal space. She was discharged on the 42nd day after operation without any complications and in the past year has returned to her usual daily life without any anastomotic site trouble.