title: Hemocompatibility of PMEA coated oxygenators used for extracorporeal circulation procedures.
abstract: An inflammatory response to cardiopulmonary bypass (CPB) caused by bioincompatibility of extracorporeal circuits is one of the major clinical issues in cardiac surgery. Recently a new coating material, poly-2-methoxyethylacrylate (PMEA), was developed to improve the biocompatibility of blood contacting surfaces. In a simulated cardiopulmonary bypass model, using fresh human whole blood, 15 membrane oxygenators (Capiox SX18, Terumo Corp., Tokyo, Japan) were compared. Five of them had the PMEA coating, five had a heparin-coated surface, and five had no surface treatment. Blood samples were taken at several time-points during a 90 minute circulation period. Changes in coagulation, complement, and blood cell alteration factors were measured by ELISA methods, plasma bradykinin levels were measured by radioimmunoassay, and expression of genes encoding cytokines TNF-alpha, interleukin-1beta, interleukin-6, and interleukin-8 was determined by semiquantitative real time RT-PCR. Platelet adhesion was significantly reduced in both the PMEA and the heparin coated circuits. Release of platelet activation marker beta-thromboglobulin was significantly higher in the uncoated control group (p < 0.01). After 5 minutes of blood circulation bradykinin levels significantly increased in all three groups (p < 0.01); however, the group with the PMEA coated oxygenators showed the lowest values. Expression of genes encoding proinflammatory cytokines in monocytes was increased in all groups, with the lowest being in the PMEA coated group. PMEA coated CPB surfaces in an in vitro experimental model showed an improved thrombogenicity, reduced bradykinin release, less platelet activation and less proinflammatory cytokines gene expression in comparison with a noncoated group. The authors assume that PMEA coating may ameliorate some of intra- and postperfusion syndromes, particularly hypotension, unspecific inflammation, hyperfibrinolysis, and blood loss.
authors.affiliation: Department of Thoracic, Cardiac, and Vascular Surgery, University of Tuebingen, Germany.
authors.forename: Anja K
authors.initials: AK
authors.lastname: Zimmermann
authors.forename: Hermann
authors.initials: H
authors.lastname: Aebert
authors.forename: Andrea
authors.initials: A
authors.lastname: Reiz
authors.forename: Mathias
authors.initials: M
authors.lastname: Freitag
authors.forename: Maria
authors.initials: M
authors.lastname: Husseini
authors.forename: Gerhard
authors.initials: G
authors.lastname: Ziemer
authors.forename: Hans P
authors.initials: HP
authors.lastname: Wendel
mesh_terms: D000179:Acrylates / Q000494:pharmacology*; D001777:Blood Coagulation; D001792:Blood Platelets / Q000378:metabolism; D001920:Bradykinin / Q000097:blood; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible; D004797:Enzyme-Linked Immunosorbent Assay; D006493:Heparin; D006801:Humans; D007249:Inflammation / Q000517:prevention & control*; D007375:Interleukin-1 / Q000097:blood / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood / Q000378:metabolism; D016209:Interleukin-8 / Q000097:blood / Q000378:metabolism; D008422:Materials Testing; D010107:Oxygenators, Membrane; D010973:Platelet Adhesiveness; D011108:Polymers / Q000494:pharmacology*; D011863:Radioimmunoassay; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015854:Up-Regulation; D001620:beta-Thromboglobulin / Q000378:metabolism
chemical_list: D000179:Acrylates; D020099:Coated Materials, Biocompatible; D007375:Interleukin-1; D015850:Interleukin-6; D016209:Interleukin-8; D011108:Polymers; D014409:Tumor Necrosis Factor-alpha; D001620:beta-Thromboglobulin; C413485:poly(2-methoxyethylacrylate); D006493:Heparin; D001920:Bradykinin