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Published on: August 21, 2020
Clinical study of biocompatibility between open and closed heparin-coated cardiopulmonary bypass circuits
Hiroyuki Tanaka1, Takanori Oshiyama, Takashi Narisawa
1Department of Thoracic Cardiovascular Surgery, Showa University Fujigaoka Hospital, 1-30 Fujigaoka, Aoba-ku, 227-8501, Yokohama, Japan. h.tanaka@showa-university-fujigaoka.gr.jp
Insights
This study compared closed versus open cardiopulmonary bypass (CPB) circuits in valvular surgery. Researchers found no significant biocompatibility differences between the two systems regarding coagulation, fibrinolysis, or inflammatory response.
Area of Science:
- Cardiovascular Surgery
- Biomedical Engineering
- Hematology
Background:
- Cardiopulmonary bypass (CPB) is essential for cardiac surgery.
- Heparin-coated circuits are used to improve biocompatibility.
- The impact of closed vs. open CPB circuits on patient response requires further investigation.
Purpose of the Study:
- To compare the clinical performance of closed and open circuit systems in heparin-coated CPB.
- To evaluate differences in coagulation, fibrinolysis, and inflammatory responses between the two systems.
- To assess the biocompatibility of closed versus open CPB circuits in valvular heart surgery.
Main Methods:
- Nineteen patients undergoing valvular heart surgery were randomly assigned to either a closed or open CPB circuit.
- Coagulation markers (platelets, fibrinogen, thrombin-antithrombin III complex), fibrinolysis markers (D-dimer, plasmin-Alpha2 plasmin inhibitor complex), and inflammatory markers (interleukin-6, polymorphic neutrophil-elastase) were measured.
- Plasma free hemoglobin and white blood cell count were also assessed at multiple time points.
Main Results:
- Both closed and open CPB circuits activated coagulation, fibrinolysis, and inflammatory responses during perfusion.
- No statistically significant differences were observed between the closed and open circuit groups for any of the measured parameters.
- The study included suction and cell-saving systems in the clinical investigation.
Conclusions:
- In valvular heart surgery utilizing suction and cell-saving systems, a closed CPB circuit did not demonstrate superior biocompatibility compared to an open circuit.
- The findings suggest that current clinical practices with open circuits are comparable to closed circuits in terms of biocompatibility outcomes.
- Further research may explore specific patient populations or different CPB configurations to identify potential advantages of closed systems.
Abstract:
The objective of this study was to investigate the difference between the closed circuit system and the open circuit system in clinical heparin-coated cardiopulmonary bypass (CPB) circuits with a centrifugal pump. We evaluated the coagulation, fibrinolysis, and inflammatory response in valvular heart surgery. Nineteen patients were assigned at random to a group for the closed circuit system or the open circuit system. This is the first report on the effect of a closed circuit in valvular surgery. We measured the platelet count, white blood cell count, plasma fibrinogen concentration, thrombin-antithrombin III complex, plasmin-Alpha2 plasmin inhibitor complex, D-dimer, interleukin-6, polymorphic neutrophil-elastase, and the plasma free hemoglobin. Blood samples were collected before the start of perfusion, 15 and 60 min after the start of perfusion, 60 min after the administration of protamine, and 1 day after the operation. During the perfusion, coagulation, fibrinolysis, and inflammatory responses were activated; however, no significant differences between the two groups were noted. In this clinical investigation with suction and the cell saving system, the closed circuit was not found to be superior to the open circuit with regard to biocompatibility.
