Heparin-coated bypass circuits: Effects on inflammatory response in pediatric cardiac operations
ABSTRACT This study was designed to investigate whether clinical signs of the inflammatory response in pediatric cardiac patients are reduced by heparin-coated cardiopulmonary bypass circuits and how this could be explained by differences in the pathophysiologic mechanisms involved.
In a randomized, prospective study 19 patients underwent cardiopulmonary bypass either with Carmeda BioActive Surface bypass circuits (n = 9) or with identical noncoated circuits (control, n = 10). Clinical parameters were recorded during the first 48 hours after the start of operation. Blood samples for determination of terminal complement complex, soluble form of E-selectin, and beta-thromboglobulin were obtained perioperatively up to 24 hours after operation.
All clinical and inflammatory mediators showed a tendency in favor of the group with heparin-coated circuits. When analyzed on a point-by-point basis there were significant differences in postoperative central body temperature, soluble E-selectin levels, and beta-thromboglobulin levels (all p < 0.05).
These data suggest that the use of heparin-coated cardiopulmonary bypass offers clinical benefit and tends to reduce the release of inflammatory mediators.
Full-textDOI: · Available from: Wim van Oeveren, Dec 30, 2013
- SourceAvailable from: Carsten Werner
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- "Numerous attempts to imitate the natural lining of the endothelium were undertaken by seeding endothelial cells on biomaterials but had limited success due to stability and vitality problems of the cells   . To avoid these problems molecular products or components of endothelial cells like heparin        , plasminogen-activators (tissue-and urokinase-type       ) and NO  were applied instead. "
ABSTRACT: Thrombomodulin (TM) serves as the endothelial cell receptor for thrombin and alters its characteristics from pro- to anticoagulant. Additionally, it promotes the formation of activated protein C. We evaluated the conservation of the overall outcome of these functions in recombinant TM linked to artificial surfaces by incubation with human whole blood in vitro. TM was covalently immobilized through poly(ethylene glycol) (PEG) spacers onto thin films of poly(octadecene alt maleic anhydride) covering planar glass substrates. TM binding to the polymer films was achieved after active ester formation at the carboxylic acid terminus of the PEG spacers and thoroughly characterized by HPLC-based amino acid analysis, immunofluorescence and ellipsometry. TM-coated samples were incubated for 3h with freshly drawn whole human blood anticoagulated with heparin (5IU/ml) using in-house developed incubation systems. The substantially reduced activation of blood coagulation (TAT) for TM-coated samples correlates well with the degree of contact activation (bradykinin and FXIIa formation) while no significant effects were observed for the platelet activation (PF4). Further, complement activation (C5a levels), was strongly diminished at the TM-containing surfaces. We conclude that the suggested method for preparation of TM immobilization may serve to prepare model substrates for studies on TM interactions but similarly provides a promising coating strategy for blood contacting medical devices.Biomaterials 10/2004; 25(21):5101-13. DOI:10.1016/j.biomaterials.2003.12.014 · 8.31 Impact Factor
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ABSTRACT: Cardiopulmonary bypass (CPB) is a technique that makes open heart surgery possible. When CPB is used the heart can be stopped while the blood circulation, oxygen delivery and carbon dioxide removal are guaranteed. In the last decades CPB has become much safer but still causes a systemic inflammation reaction (SIRS). SIRS may cause morbidity and, when severe, even mortality. SIRS reaction is worse in neonates and infants due to the immaturity of organs and the unfavourable ratio of CPB prime volume to patient circulating volume. This thesis focuses on different techniques that have been developed to decrease the deleterious effects of CPB in pediatric cardiac surgery.We compared in a retrospective way 2 groups of 99 patients each, in one group we used MUF and in the other group ultrafiltration was not used. We concluded that modified ultrafiltration decreases blood transfusion requirements and chest drain loss after pediatric cardiac surgery.The ratio between CPB prime solution and circulating blood volume is highest in the neonatal patient. It has been reported that neonates have a poor antioxidative and iron binding capacity. During CPB, prooxidative substances, such as nonprotein-bound iron, are released while the plasma antioxidant capacity decreases, resulting in excess accumulation of Radical Oxygen Species.Contact of blood with the non-biological surfaces of the CPB system has been designated as the main cause of complement activation. Improving the biocompatibility of CPB systems by means of decreasing the contact activation of blood elements and thereby attenuating the inflammatory response is evidently desired, and for this reason several coatings have been developed. Information is lacking about the interaction of medication and the CPB prime or the coating of a CPB system. We did not observe any interaction between dexamethasone and the PHISIOÂ® coating, b ut have observed that in the group with PHISIOÂ® coating without dexamethasone the production of IL-8 was significantly increased. In literature many controversies are found on the topic of CPB coatings. It is difficult to compare these studies due to different patient groups, differences in measured parameters and lack of proper control groups.