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Correspondence  |   July 2003
About Dosage Schemes and Safety of Tranexamic Acid in Cardiac Surgery
Author Affiliations & Notes
  • Jacek M. Karski, F.R.C.P.C.
    *
  • *Toronto General Hospital, Toronto, Ontario, Canada.
Article Information
Correspondence
Correspondence   |   July 2003
About Dosage Schemes and Safety of Tranexamic Acid in Cardiac Surgery
Anesthesiology 7 2003, Vol.99, 236. doi:
Anesthesiology 7 2003, Vol.99, 236. doi:
In Reply:—
We appreciate your interest in our work and would like to take this opportunity to reply to your comments. First, we would like to apologize for misquoting your tranexamic acid (TA) administration regimen. However, we think that the principal behind the administration of a loading dose remains the same (1 g of TA over 20 min).
Regarding the criticism with respect to validity of increased TA dosage for patients undergoing complex cardiac surgery, we would like to emphasize that our previous studies (J Thorac Cardiovasc Surg  1995; 110:835–42) showed that higher TA dose regimens were more effective in reducing postoperative bleeding compared to a lower single-dose regimen.
With respect to safety aspects of TA, we must admit that we have never claimed that the use of any antifibrinolytics during cardiac surgery is a safe practice in the face of circulatory arrest. All information in the literature about vascular thrombosis after the use of antifibrinolytics in cardiac surgery is anecdotal. We have recently reviewed stroke rates (as an indicator of vascular thrombosis) in our prospectively collected database of 18,000 primary coronary artery bypass graft patients with respect to utilization of TA. Stroke rates of 1.2–1.4% were similar between the two groups of patients, regardless of TA assignment. Furthermore, we have conducted a prospective randomized placebo controlled trial that demonstrated that there was no difference in early coronary graft patency between high-dose TA and placebo groups.