A Comparison of Anaesthetic Methods for Total Knee Replacement Surgery

Overview

Open-labelled, randomised controlled trial. Patients will be assessed pre-operatively, at 24 and 48 hours for the primary outcome and secondary outcomes (except for Oxford Knee Score which will be assessed pre-operatively and at 6 months post-operatively by the ortho-paedic team). Primary Objective: To demonstrate whether adductor canal nerve infusions result in superior patient mobilisation within the first 48 hours following total knee replacement compared to femoral nerve catheter infusions. Secondary Objective: To identify whether adductor canal nerve infusions result in superior analgesia within the first 48 hours following total knee replacement compared to femoral nerve catheter infusions.

We are comparing a continuous adductor canal block with a low concentration continuous femoral nerve block. We currently use a low dose femoral nerve catheter based technique as part of our standard treatment strategy for total knee arthroplasty. The use of a catheter provides prolonged analgesia compared to a single shot block, and also allows a lower concentration of local anaesthetic to be employed, thus potentially reducing the incidence of motor blockade. The concentration of local anaesthetic employed in our routine practice (0.0625% L- Bupivacaine) is lower than that routinely used in many other centres, and most clinical studies have compared higher concentrations of local anaesthetic - this might be expected to produce more motor blockade. The concentration we use is higher than the minimum effective concentration for a femoral catheter infusion for knee arthroplasty.

Conditions