Tranexamic Acid Dosing for Cardiac Surgical Patients With Chronic Renal Dysfunction

METHODS: This prospective cohort study enrolled 48 patients with stages 1–5 CRD, classified by Kidney Disease Outcome Quality Initiative. Patients were separated into 2 treatment groups. A “low-risk” group underwent simple aortocoronary bypass or single-valve repair/replacement and received a 50 mg/kg TXA bolus. A “high-risk” group underwent redo, aortic, multiple valve or combination surgery and received the Blood Conservation Using Anti-fibrinolytics Trial dosing regimen (loading dose 30 mg/kg, infusion 16 mg/kg/h with 2 mg/kg in pump prime). Primary outcome identified changes in TXA clearance and distribution volume, which provided the rationale for dose adjustment. Descriptive clinical outcomes assessed postoperative seizures, blood loss, ischemic-thrombotic complications, in-hospital mortality, and length of hospital stay.

RESULTS: TXA concentrations were elevated and sustained above the therapeutic threshold for approximately 12 hours in high-risk stages 3–5 groups, in accordance to CRD severity.

CONCLUSIONS: Using a pharmacokinetic model, we propose a simple new TXA dosing regimen that optimizes maximal antifibrinolysis and avoids excessive drug dosing.