Contributions
Abstract: PB1824
Type: Publication Only
Session title: Thrombosis and vascular biology - Biology & Translational Research
Background
Cardiac surgery under cardiopulmonary bypass (CBP) still involve major bleeding of which platelet injury is generally believed to be its primary nonsurgical cause. However, in some patients, excessive fibrinolysis may be the primary etiology of blood loss in postoperative period. The D-dimer assay, a measure of cross-linked fibrin degradation product, constitutes a specific test for fibrinolysis.
Aims
In this present study, we sought to assess the changes of D-dimers concentrations in cardiac patients before and after CBP and whether the D-dimers formation correlates with postoperative bleeding.
Methods
A total of 30 patients undergoing cardiac surgery under CBP were included in a prospective observational study. Patients’ variables, postoperative bleeding volume, transfusions during the operation and 24 hours after, laboratory variables in preoperative, intraoperative and postoperative period (hemoglobin, hematocrit, platelet count, prothrombin rate, activated partial thromboplastin time, fibrinogen level) were registered. D-dimers concentration was measured using an enzyme-linked immunosorbent assay (ELISA) technique VIDAS before CBP and 5 minutes after heparin neutralization.
Results
There were 30 patients with an average age of 54.4 years old (18-79 years old).Based on the surgery indication, Patients were split up into three groups : coronary insufficiency (P)(N=12), valvulopathy (V)(N=14) and other reasons (C) (N=4). The mean preoperative D-dimers concentration was 509ng/ml ranging from 150ng/ml to 2200ng/ml. Among groups, the mean D-dimers levels were estimated as follows: 438ng/ml in group P, 625ng/ml in group V and 314ng/ml in group C. In postoperative time, D-dimers levels were significantly increased (p=0.01).In fact, the mean D-dimers concentration were 889ng/ml ranging from 270ng/ml to 3940ng/ml. Regarding groups, the D-dimers levels were respectively 527ng/ml, 1320ng/ml and 468ng/ml in group P, group V and group C with a statistically significant difference (p=0.05).Therefore, group V showed the highest increase of D-dimers level after CBP. This latter group consisted predominantly of female patients (H/F=4/10), showed the longest aortic cross clamp time (65.5min), had the highest mean number of red blood cell units transfused within and after surgery (1±0.96 and 1±1.24 units respectively) and the highest mean number of fresh frozen plasma transfused ( 2±2.9 units). On the other side, based on the median value of the rate of fall of hemoglobin between preoperative and postoperative time which was estimated at 2.5 g/dl, we defined two groups (N=15).There was no statistically significant difference in the mean D-dimers levels in the two groups (P=0.08) contrary to preoperative hemoglobin level and postoperative bleeding volume 24 hours after surgery. Furthermore, our study didn’t demonstrate a correlation between D-dimers concentration and postoperative bleeding loss.
Conclusion
In summary, our results indicate, in small number, that there is an activation of fibrinolysis in patients undergoing CBP surgery as shown by the elevation of D-dimers level in the early postoperative period. A large study is desirable to study fibrinolysis in patients undergoing CBP, its pathophysiological implications and its correlation with hemorrhage complications
Keyword(s):
Abstract: PB1824
Type: Publication Only
Session title: Thrombosis and vascular biology - Biology & Translational Research
Background
Cardiac surgery under cardiopulmonary bypass (CBP) still involve major bleeding of which platelet injury is generally believed to be its primary nonsurgical cause. However, in some patients, excessive fibrinolysis may be the primary etiology of blood loss in postoperative period. The D-dimer assay, a measure of cross-linked fibrin degradation product, constitutes a specific test for fibrinolysis.
Aims
In this present study, we sought to assess the changes of D-dimers concentrations in cardiac patients before and after CBP and whether the D-dimers formation correlates with postoperative bleeding.
Methods
A total of 30 patients undergoing cardiac surgery under CBP were included in a prospective observational study. Patients’ variables, postoperative bleeding volume, transfusions during the operation and 24 hours after, laboratory variables in preoperative, intraoperative and postoperative period (hemoglobin, hematocrit, platelet count, prothrombin rate, activated partial thromboplastin time, fibrinogen level) were registered. D-dimers concentration was measured using an enzyme-linked immunosorbent assay (ELISA) technique VIDAS before CBP and 5 minutes after heparin neutralization.
Results
There were 30 patients with an average age of 54.4 years old (18-79 years old).Based on the surgery indication, Patients were split up into three groups : coronary insufficiency (P)(N=12), valvulopathy (V)(N=14) and other reasons (C) (N=4). The mean preoperative D-dimers concentration was 509ng/ml ranging from 150ng/ml to 2200ng/ml. Among groups, the mean D-dimers levels were estimated as follows: 438ng/ml in group P, 625ng/ml in group V and 314ng/ml in group C. In postoperative time, D-dimers levels were significantly increased (p=0.01).In fact, the mean D-dimers concentration were 889ng/ml ranging from 270ng/ml to 3940ng/ml. Regarding groups, the D-dimers levels were respectively 527ng/ml, 1320ng/ml and 468ng/ml in group P, group V and group C with a statistically significant difference (p=0.05).Therefore, group V showed the highest increase of D-dimers level after CBP. This latter group consisted predominantly of female patients (H/F=4/10), showed the longest aortic cross clamp time (65.5min), had the highest mean number of red blood cell units transfused within and after surgery (1±0.96 and 1±1.24 units respectively) and the highest mean number of fresh frozen plasma transfused ( 2±2.9 units). On the other side, based on the median value of the rate of fall of hemoglobin between preoperative and postoperative time which was estimated at 2.5 g/dl, we defined two groups (N=15).There was no statistically significant difference in the mean D-dimers levels in the two groups (P=0.08) contrary to preoperative hemoglobin level and postoperative bleeding volume 24 hours after surgery. Furthermore, our study didn’t demonstrate a correlation between D-dimers concentration and postoperative bleeding loss.
Conclusion
In summary, our results indicate, in small number, that there is an activation of fibrinolysis in patients undergoing CBP surgery as shown by the elevation of D-dimers level in the early postoperative period. A large study is desirable to study fibrinolysis in patients undergoing CBP, its pathophysiological implications and its correlation with hemorrhage complications
Keyword(s):