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Published on: September 15, 2023
Closed cardiopulmonary bypass circuits suppress thrombin generation during coronary artery bypass grafting
Atsushi Nakahira1, Yasuyuki Sasaki, Hidekazu Hirai
1Department of Cardiovascular Surgery, Osaka City University Graduate School of Medicine, Osaka City University Hospital, 1-4-3 Asahimachi, Abeno-ku, Osaka 545-0051, Japan. osushi123@med.osaka-cu.ac.jp
Insights
Closed cardiopulmonary bypass circuits significantly reduce thrombin generation and coagulofibrinolytic activation during coronary artery bypass grafting, minimizing harmful blood clotting markers.
Area of Science:
- Cardiovascular Surgery
- Hemostasis and Thrombosis
- Biomedical Engineering
Background:
- Thrombin generation is a significant concern during cardiopulmonary bypass (CPB) in cardiac surgery.
- Existing open-circuit systems with cardiotomy suction contribute to this activation.
- Minimizing thrombin generation is crucial for patient outcomes.
Purpose of the Study:
- To compare the impact of open versus closed CPB circuits on coagulation and fibrinolysis.
- To evaluate thrombin generation markers under standardized surgical conditions.
Main Methods:
- Randomized controlled trial with 30 coronary surgery patients.
- Comparison of open circuits (reservoirs, cardiotomy suction) vs. closed circuits (cell-saving device).
- Analysis of coagulation markers (TAT, fibrinogen degradation products, D-dimer) at eight time points.
Main Results:
- Closed circuits significantly suppressed thrombin-antithrombin III (TAT), fibrinogen degradation products, and D-dimer during CPB.
- Open circuits showed significant increases in these markers (P<0.0001).
- Peak TAT in the open group correlated with CPB time and D-dimer levels.
Conclusions:
- Closed CPB circuits effectively minimize thrombin generation and coagulofibrinolytic activation.
- This approach is beneficial during coronary artery bypass grafting.
- Further research is needed to isolate the specific contributions of open reservoirs and cardiotomy suction.
Abstract:
Thrombin generation is considered unavoidable during cardiac surgery using cardiopulmonary bypass (CPB). We compared the effects of open and closed circuits on coagulation and fibrinolysis under identical conditions of priming volume, heparin-coating, and anticoagulation and transfusion protocols. Thirty coronary surgery patients were randomized to surgery using open circuits with open reservoirs and cardiotomy suction (open group, n=15) or closed circuits without either (closed group, n=15). In the closed group, a cell-saving device was used instead of cardiotomy suction. Blood samples were collected at eight time points from before the operation to the first postoperative morning. Thrombin-antithrombin III (TAT), fibrinogen degradation products, and D-dimer were not elevated during CPB in the closed group, but were significantly increased in the open group (P<0.0001 for all markers). The peak TAT value at the termination of CPB in the open group was significantly correlated with CPB time (r(2)=0.879, P=0.037) and the simultaneous peak D-dimer value (r(2)=0.640, P=0.040). In conclusion, the use of closed circuits maximally suppressed thrombin generation and coagulofibrinolytic activation during coronary artery bypass grafting. The respective contribution of open reservoirs and cardiotomy suction to the perioperative thrombin generation remains to be elucidated.
