Tranexamic Acid (TXA) — Detail
Cyklokapron · Lysteda (PO)
Antifibrinolytic / synthetic lysine analog
Synthetic lysine analog. Competitively binds plasminogen LYSINE binding sites, preventing plasminogen activation to plasmin. Inhibits fibrinolysis without inducing hypercoagulability per se.
Indications
- •Trauma hemorrhage (CRASH-2: 1g IV over 10 min + 1g over 8 h within first 3 h reduces all-cause mortality)
- •Postpartum hemorrhage (WOMAN trial: 1g IV reduces death from bleeding)
- •Cardiac surgery (reduces blood loss + transfusion)
- •Spine surgery, total joint, liver transplant
- •Hereditary angioedema prophylaxis
- •Heavy menstrual bleeding (PO formulation)
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Trauma (CRASH-2) | 1 g IV over 10 min within FIRST 3 H of injury, then 1 g over 8 h | — |
| Postpartum hemorrhage (WOMAN) | 1 g IV over 10 min as soon as PPH diagnosed; can repeat 30 min later | — |
| Cardiac surgery | Loading 10-30 mg/kg IV + infusion 1-16 mg/kg/h | — |
| Spine/major ortho | 10-15 mg/kg IV at incision; some institutions add infusion | — |
| Topical (joint, surgical field) | 1-3 g in 100-200 mL saline applied topically | — |
| Pediatric (e.g. congenital cardiac) | (weight-based) | 10 mg/kg IV at induction + 1 mg/kg/h infusion |
Pharmacokinetics
Onset 5-10 min IV. Half-life ~2-3 h. Renal excretion >95% unchanged.
Hemodynamic effects
Hemodynamically neutral. Rapid IV bolus may cause transient hypotension or visual disturbances — give over 10 min for 1 g dose.
Side effects
- !Visual disturbances + hypotension (rapid bolus) — give over ≥10 min
- !Seizures (high-dose cardiac surgery — TXA is GABAA antagonist; reduce dose with CSF leak / BBB disruption)
- !Theoretical thromboembolism increase — meta-analyses show no clear increase
- !GI upset (PO)
- !Headache + nausea
Contraindications
- ×Active intravascular thrombosis (PE, DVT being treated)
- ×Subarachnoid hemorrhage (some debate)
- ×Severe renal impairment (dose reduction)
- ×Acute color vision deficit
Clinical pearls
- ★TIMING for trauma: 1 g WITHIN 3 HOURS reduces mortality. After 3 hours, NOT beneficial and may HARM.
- ★PPH: 1 g IV as soon as diagnosed; can repeat 30 min later.
- ★CARDIAC SURGERY: reduces bleeding + transfusion ~25%. Seizure risk at high-dose protocols (>50 mg/kg) — modern dose more conservative (10-30 mg/kg).
- ★SPINE SURGERY: 15 mg/kg IV at incision is standard — reduces blood loss + transfusion in scoliosis + multilevel fusion.
- ★TOPICAL: 1-3 g in saline applied to surgical wound (knee, hip) reduces bleeding without systemic exposure.
- ★Approximately $5-10 per dose IV — extreme cost-effectiveness.
📊 Related teaching panels
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