A heparinised CPB system in patients with unstable angina. Coagulation , complement and cytokine cascade effects

PURPOSE: To investigate assumed benefits of heparin coated cardiopulmonary bypass systems from standard non-coated CBP systems in unstable angina patients with preoperative heparinisation. STUDY DESIGN: Coagulation, complement, cytokine and Sonoclot parameters, were analyzed before total heparinisation prior to surgery, during cardiopulmonary bypass, after protamine to 48 hours after surgery. MATERIALS & METHODS: Twenty patients were randomized to either recieve a Bentley-Baxter Duraflo II heparin coated CBP-system (10 patients) or a non-coated Baxter system (10 patients). ACT-levels were kept over 480 sees in both groups with a with a schematic anticoagulation regime according to: 1. an initial 300 IU/kg BW heparin dose; 2. if necessary being repeated; 3. then ensued by plasma 2 + 2 units; 4. a third dose of heparin (300 ID/kg BW) was then administered; and finally 5. antithrombin concentrate was administered if ACT still level remained below 480 s. RESULTS: Soluble fibrin (s-fibrin) and thrombin-antithrombin complex (TAT) indicated an ongoing activation in spite of the preoperative heparinanticoagulation in unstable angina patients. Intaoperative analyses with both these assays indicated significantly lower thrombin activation with a heparin coated CBP-system. The results of the complement, cytokine and platelet function analyzes and clinical data evaluation will be presented at the meeting. CONCLUSION: A heparin coated cardiopulmonary bypass system induced less activation of the coagulation cascade in unstable angina patients. This could forward a reduction of heparin and reduced need for plasma /antihrombin in patients with unstable angina - increased rise for heparin resistance during CBP- when a heparin coated CBP-system is used, but remains to be studied.