S100β correlates with neurologic complications after aortic operation using circulatory arrest

Background. Astrocyte protein S100β is a potential serum marker for neurologic injury. The goals of this study were to determine whether elevated serum S100β correlates with neurologic complications in patients requiring hypothermic circulatory arrest (HCA) during thoracic aortic repair, and to determine the impact of retrograde cerebral perfusion (RCP) on S100β release in this setting.

Methods. Thirty-nine consecutive patients underwent thoracic aortic repairs during HCA; RCP was used in 25 patients. Serum S100β was measured preoperatively, after cardiopulmonary bypass, and 24 hours postoperatively.

Results. Neurologic complications occurred in 3 patients (8%). These patients had higher postbypass S100β levels (7.17 ± 1.01 μg/L) than those without neurologic complications (3.63 ± 2.31 μg/L, p = 0.013). Patients with S100β levels of 6.0 μg/L or more had a higher incidence of neurologic complications (3 of 7, 43%) compared with those who had levels less than 6.0 μg/L (0 of 30, p = 0.005). Retrograde cerebral perfusion did not affect S100β release.

Conclusions. Serum S100β levels of 6.0 μg/L or higher after HCA correlates with postoperative neurologic complications. Using serum S100β as a marker for brain injury, RCP does not provide improved cerebral protection over HCA alone.