Surface modification of extracorporeal circuits: Is there really an impact on cerebral performance after cardiopulmonary bypass?

Background: Pathophysiology of extracorporeal circulation is multifactorial, and the link between newly developed "biomaterials" and clinical outcome is not easy to illustrate. Material and methods: We designed a randomized, double-blinded, prospective study in order to verify the impact of a new surface modification [SMAR(X)T] in combination with an optimized blood air interface, on the cerebral performance after cardiopulmonary bypass. 80 patients were randomly divided into two subgroups (SMARxT vs. standard PVC control) and analyzed for the kinetic of cerebral ischemia markers neuronspecific enolase, protein S100 and neuropsychologically tested with the Mini-Mental-Status Test (MMST) before and after the operation. Results: We could not show significant differences of protein S100 and neuron-specific enolase (NSE) levels between SMAR(X)T patients and the controls, but the incidence of neurological complications was exceptionally low. Although no statistically significant differences could be obtained for the MMST, the different pointloss between both groups trends toward a better cerebral performance in SMAR(X)T patients. Conclusion: The use of a biologically inert circuit in combination with an optimized perfusion management seems to be worthy of recommendation.