Amelioration of the bleeding tendency of preoperative aspirin after aortocoronary bypass grafting.
BACKGROUND
Aspirin therapy is widely used in the treatment of cardiac disease. It has been recognized as a causative factor for increased bleeding and blood loss after open heart operations.


METHODS
To determine whether high-dose aprotinin maintained its efficacy in reducing blood loss in the presence of aspirin pretreatment in patients undergoing aortocoronary bypass, we performed a double blind study on 60 adult patients. Half received high-dose aprotinin (Trasylol) and half placebo.


RESULTS
Total hemoglobin loss, the primary efficacy variable was reduced from 36.1 +/- 31.4 g (mean +/- SD) to 14.1 +/- 16.0 g (p = 0.002). Blood loss was reduced intraoperatively and total loss was reduced from 837.3 mL +/- 404.9 mL to 368.7 mL +/- 164.3 mL (p < 0.001). The number of patients who did not receive any donor blood products was significantly higher in the aprotinin-treated patients (56.7% versus 23.3%, p = 0.008). Activation of the clotting cascade was significantly less in the treated patients toward the end of cardiopulmonary bypass both by measurement of thrombin-antithrombin III complex (p < 0.0001) and prothrombin fragment 1 + 2 (p < 0.0001). D-Dimer generation was significantly less from the onset of bypass and after reversal of heparin in the aprotinin-treated patients (p < 0.0001).


CONCLUSIONS
High-dose aprotinin was highly effective in reducing bleeding in this high-risk group of patients. Biochemical analyses suggest the mechanism by which aspirin increases blood loss after cardiopulmonary bypass is different from the blood-preserving effects of aprotinin, which is acting as an antifibrinolytic agent.
Bidstrup
B P
BP
Wellington Hospital, London, England. b.bidstrup@mailbox.uq.edu.au
Hunt
B J
BJ
Sheikh
S
S
Parratt
R N
RN
Bidstrup
J M
JM
Sapsford
R N
RN
D000328:Adult; D000933:Antifibrinolytic Agents / Q000627:therapeutic use*; D000990:Antithrombin III / Q000032:analysis; D007611:Aprotinin / Q000627:therapeutic use*; D001241:Aspirin / Q000009:adverse effects*; D016063:Blood Loss, Surgical / Q000517:prevention & control*; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000601:surgery; D004311:Double-Blind Method; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects*; D006490:Hemostatics / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000032:analysis; D011300:Preoperative Care; D011498:Protein Precursors / Q000032:analysis; D011516:Prothrombin / Q000032:analysis
D000933:Antifibrinolytic Agents; D005343:Fibrinolytic Agents; D006490:Hemostatics; D010446:Peptide Fragments; D011498:Protein Precursors; C029733:prothrombin fragment 1; C044183:prothrombin fragment 2; D000990:Antithrombin III; D011516:Prothrombin; D007611:Aprotinin; D001241:Aspirin