Pranas Grybauskas

Influence of aspirin or heparin on platelet function and postoperative blood loss after coronary artery bypass surgery

The aim of the study was to assess the effect of aspirin or heparin pretreatment on platelet function and bleeding in the early postoperative period after coronary artery bypass grafting (CABG) surgery. Seventy-five male patients with coronary artery disease who underwent CABG with cardiopulmonary bypass (CPB) were studied. The patients were divided into three groups: Group 1 (n = 25) included patients receiving aspirin pretreatment, Group 2 (n = 22) received heparin pretreatment, and Group 3 (n = 28) included patients who received no antiplatelet or anticoagulant pretreatment. Twenty-four hours after surgery, all patients were administered aspirin therapy that was continued throughout their hospitalization period. We assessed the following preoperative blood coagulation indices: activated partial thromboplastin time (aPTT), international normalized ratio (INR), and fibrinogen. We compared platelet count and platelet aggregation induced by adenosinediphosphate (ADP) before surgery, 1 h after surgery, 20 h after surgery and on the seventh postoperative day. We assessed drained blood loss within 20 postoperative hours. Preoperative blood coagulation indices did not differ among the groups. Platelet count was also similar. One hour after surgery, platelet count significantly decreased in all groups (p <0.001), after 20 postoperative hours it did not undergo any marked changes, and on the seventh postoperative day, it significantly increased in all groups (p <0.001). Before surgery, the lowest index of ADP-induced platelet aggregation was found in Group 1 (p <0.05). One hour after surgery, platelet aggregation significantly decreased in all groups, most markedly in Group 3 (p <0.001), yet after 20 h, its restitution tendency and a significant increase in all groups was noted. On the seventh day, a further increase in the statistical mean platelet aggregation value was noted in Groups 2 and 3. Comparison of platelet aggregation after 20 postoperative hours and on the seventh day after surgery revealed a significantly higher than 10% increase of the index in 32% of patients in Group 1 (p <0.05), 27.3% of patients in Group 2 (p <0.05) and in 35.7% of patients in Group 3 (p <0.001). The lowest statistically significant value of postoperative blood loss was noted in Group 2 (p <0.01). Our study has shown that aspirin or heparin pretreatment had no impact on the dynamics of platelet function in the early postoperative period after CABG. The lowest postoperative blood loss was noted in patients pretreated with heparin.

Influence of early re-infusion of autologous shed mediastinal blood on clinical outcome after cardiac surgery

Various strategies have been proposed to decrease allogeneic blood transfusion requirements after cardiac surgery. The aim of the study was to evaluate the efficacy of collected and re-infused autologous shed mediastinal blood on a patients postoperative course. Ninety patients who underwent heart surgery with cardiopulmonary bypass (CPB) were studied. The patients were divided into two groups: Group 1 (n = 41) received the centrifuged autologous shed mediastinal blood collected from the cardiotomy reservoir 4 hours after surgery; in Group 2 (n = 49) all shed mediastinal blood was discarded (control group). Haemoglobin (Hb), haematocrit (Hct), C-reactive protein values, and leucocyte count were compared before surgery, at 4 h and 20 h after surgery, and on the fifth postoperative day. We have measured serum procalcitonin (PCT) concentration at 4 h and 20 h after CPB. We assessed drained blood loss within 20 postoperative hours. Leucocyte count, Hb, Hct values, C-reactive protein, and procalcitonin concentration did not differ between the groups before and at 4 h after surgery. Hb, Hct level, and leucocyte count were similar at 20 hours and on the fifth day after surgery. At 20 hours after surgery, an increase of serum PCT concentration (>0.5—2 ng/mL) was more frequent in Group 2 (58.3% vs. 33.3%; p = 0.03). On the fifth postoperative day, C-reactive protein concentration was lower in Group 1 (71.74 ± 15.23; p < 0.01) compared to Group 2 (93.53 ± 20.3). Postoperative blood loss did not differ between the groups. Requirement for allogeneic blood transfusion was significantly lower in Group 1 (14.6% vs. 38.8%; p < 0.02). Patients in Group 1 developed less infective complications compared with Group 2 (2.4% and 16.3%, respectively; p < 0.05). The length of postoperative in-hospital stay was shorter in Group 1 compared with Group 2 (9.32 ± 2.55 and 16.45 ± 6.5, respectively; p < 0.05). We conclude that postoperative re-infusion of autologous red blood cells processed from shed mediastinal blood did not increase bleeding tendency and systemic inflammatory response and was effective in reducing the requirement for allogeneic transfusion, the rate of infective complications and the length of postoperative in-hospital stay. Perfusion (2007) 22, 345—352.

Influence of Radiofrequency Catheter Ablation on Platelet Aggregation

the objective of this article was to find out how radiofrequency catheter ablation (RFA) influences platelet aggregation (PA), and the dependence on the total energy (TE) of RFA used and the cause of arrhythmia. We investigated 97 patients. PA was analyzed before, after, and in 24 hours after RFA. ADP- and epinephrine-induced PA significantly decreased after RFA by 5% and 8.9% (P < .001), respectively, and increased in 24 hours close to baseline. PA induced by ADP and collagen did not radically depend on the TE. Epinephrine-induced PA decreased after RFA by 0%, 8% (P < .05), and 16.9% (P < .01) in groups of patients where the TEs used were <4000 J, 4000 to 15 000 J, and >15 000 J, respectively. There were no significant differences in PA between groups based on the cause of arrhythmia. ADP- and epinephrine-induced PA significantly decreased after RFA and returned close to baseline in 24 hours. Epinephrine-induced PA was inversely associated with the TE used for RFA.