Abstract
Introduction
Tranexamic acid (TXA) reduces total knee replacement (TKR) & total hip replacement (THR) blood loss. We launched a ‘fast track’ protocol to reduce inpatient stay including a single 15mg/kg dose of TXA. We conducted a retrospective cohort analysis on haemoglobin balance and transfusion requirement before and after the protocol, which aimed to reduce blood loss during lower limb arthroplasty.
Methods
Patients undergoing primary cemented THR or TKR were drawn from the periods: control 1/10/06 to 31/3/07; fast track 1/4/08 -31/7/08. We identified pre- and post-operative Day 1 haemoglobin concentration (Hb g/dl), and transfusion number & timing. Transfusion trigger was Hb<8 unless symptomatic. In patients transfused before the Day 1 assay, we corrected Hb drop for number of units given, (1 unit ≍ 1g/dl). Outcome measures are Day 1 Hb drop corrected for transfusion (t-test) and number transfused (Chi-squared).
Results
We excluded 3 patients pre-operatively. All patients had pre-operative Hb & all apart from 9 (excluded) fast track patients had Day 1 Hb assay.
Conclusions
Correcting Hb drop for transfusion gives a single measure of blood loss independent of clinical management. The protocol demonstrated reduced blood loss of about 50% in TKR and 30% in THR, and reduced transfusion rates. Other studies show comparable reductions using maintenance dosing. A single dose of 15mg/Kg TXA before incision is as effective.
The fast track protocol reduced in-patient stay from 5.5 to 2.3 days. Reduction in peri-operative blood loss may make an important contribution to recovery.
