# Predicting Blood Loss and Evaluating Tranexamic Acid Efficacy in Staged Bilateral Total Knee Arthroplasty

## TL;DR

This study examines how blood loss in the first knee surgery predicts loss in the second and how tranexamic acid timing affects bleeding in staged knee replacements.

## Contribution

The study introduces a novel approach to predicting blood loss and evaluating tranexamic acid efficacy in staged bilateral knee surgeries.

## Key findings

- First-stage blood loss moderately predicts second-stage loss in non-TXA cases.
- TXA administered in the second stage showed a trend toward reduced blood loss.
- TXA administered in both stages did not significantly reduce blood loss between legs.

## Abstract

Background

This retrospective study aimed to evaluate the predictive capacity of first-stage blood loss for second-stage blood loss and to assess the impact of varying tranexamic acid (TXA) administration timing on hemostatic efficacy within the same patient undergoing staged bilateral total knee arthroplasty (TKA).

Methods

A retrospective analysis was conducted on 100 patients (200 knees) who underwent staged bilateral primary TKA performed by a single surgeon. Patients were categorized into three groups based on TXA administration: no TXA (NT, 106 knees), TXA administered only during the second stage (H, 42 knees), and TXA administered during both procedures (T, 52 knees).

Results

In the NT group, a moderate correlation was observed between blood loss in the first and second legs (p=0.042, r=0.438), suggesting that first-stage blood loss can predict second-stage blood loss. The H group showed a trend towards reduced blood loss in the second, TXA-treated leg (p=0.068), indicating a potential benefit of TXA administration in the second stage. However, no significant difference in blood loss was observed between the two legs in the T group (p=0.657), and no correlation was found between blood loss in the two legs (p=0.070).

Conclusions

These findings suggest that in non-TXA cases, first-stage blood loss can be used to tailor perioperative management for the second stage. Furthermore, the variability in TXA efficacy highlights the need for individualized TXA dosing strategies. Future studies should investigate optimal TXA dosing and administration methods to enhance bleeding management in staged bilateral TKA.