Haemoadsorption: effective in reducing circulating fragments of the endothelial glycocalyx during cardiopulmonary bypass in patients undergoing on-pump cardiac surgery?

BACKGROUND The vascular endothelial glycocalyx is susceptible to ischaemia and hypoxia. Released soluble components of the endothelial glycocalyx (EG) have been identified as potential damage associated molecular patterns (DAMPs) able to enhance an ongoing inflammatory response. Shedding of the EG has been associated with released atrial-natriuretic peptide (ANP) during cardiac surgery procedures. A novel haemoadsorption technique (CytoSorb®) has been shown to effectively remove molecules up to 55 kDa unspecifically from circulation. It is not known whether ANP or glycocalyx components can be removed successfully by this technique. METHODS In 15 patients undergoing on-pump cardiac surgery, the haemoadsorption device was integrated in the cardiopulmonary bypass (CPB) circuit. Pre- and post-adsorber concentrations of ANP, heparan sulphate (HEP), syndecan-1 (SYN) and hyaluronan (HYA) were measured at 10 (T1), 30 (T2), and 60 (T3) minutes after aortic cross-clamping and complete CPB. RESULTS Haemoadsorption significantly reduced mean HEP concentrations (-157.5 [333.4] ng/ml; p<0.001) post adsorber. For ANP and SYN no statistically significant changes were detected whereas mean [SD] HYA concentrations even increased significantly (+21.6 [43.0] ng/ml; p < 0.001) post adsorber. CONCLUSIONS In this study representing a real-life scenario, we could demonstrate that the novel hemoadsorption device (CytoSorb®) was able to effectively adsorb HEP from the circulation if integrated in a CPB circuit. However, blood concentrations of HYA, SYN, and ANP could not be reduced during CPB in our investigation.