Background and Aims:
Total knee arthroplasty (TKA) may result in blood loss with anaemia and need of blood transfusion.That increases the risk of complications delaying mobilization and increasing length of stay. Multiples strategies have been developed to prevent blood loss,such as use of fibrinolytics agents (like tranexamic acid-TXA) and use of local infiltration anaesthesia (LIA) incorporating vasoconstrictors.
Methods:
In this retrospective observational study, 21 patients submitted to primary TKA were recruited. Spinal anaesthesia was performed in all patients. In 11 patients control analgesia (PCA) with femoral nerve block plus catheter was performed. In the other 10 patients, the same femoral nerve block was performed with the addition of LIA technique (Intracapsular: 80 mL Ropivacaine + Epinephrine 6 ug/ml. Subcutaneous: 20 mL Ropivacaine) and a dose of 1 g of intravenous TXA was administrated. Were analysed: haemoglobin values (preoperative and after 24 hours), amount of drainage output at Post Anesthesia Care Unit (PACU), transfusional requirements and length of stay.
Results
This preliminary study showed a reduction in the drainage volume at PACU in the LIA+TXA group (LIA+TXA group:260ml ± 130; control group: 479ml ± 323 p=0,072).The variation of haemoglobin after 24 hours was greater in the control group (LIA+TXA group: 2.9±0.84; control group 3.4±1.8 p=0,43).4 patients in control group and none in LIA+TXA group was transfused.There were no significant differences between the groups in terms of hospital stay.
Conclusions:
LIA and TXA in patients undergoing primary TKA seem to decrease postoperative bleeding,variation in haemoglobin and need of blood transfusion.However further studies are needed to establish the benefits.

LOCAL INFILTRATION ANAESTHESIA AND TRANEXAMIC ACID REDUCING BLOOD LOSS AND TRANSFUSION REQUERIMENTS IN TOTAL KNEE ARTHROPLASTY