Ropivacaine plasma concentrations are similar during continuous lumbar plexus blockade using the anterior three-in-one and the posterior psoas compartment techniques.

Purpose: To compare ropivacaine blood concentrations obtained after a continuous lumbar plexus block performed either by the anterior three-in-one femoral (FEM) technique or the posterior (psoas compartment; PSOAS) technique.

Methods: As a substudy of a larger clinical trial, 24 patients were randomly allocated to receive a bolus of 30 mL of ropivacaine 0.5% plus epinephrine 1:200,000 followed by an infusion of ropivacaine 0.

The posterior lumbar plexus (psoas compartment) block and the three-in-one femoral nerve block provide similar postoperative analgesia after total knee replacement.

Purpose: To compare the efficacy of a continuous posterior lumbar plexus (PSOAS) block to a continuous three-in-one femoral nerve (FEM) block in patients undergoing primary total knee replacement (TKR).

Methods: Sixty patients were randomly allocated to receive iv patient-controlled morphine analgesia (PCA), PCA plus a continuous FEM block with 30 mL ropivacaine 0.5% and epinephrine 1:200,000 bolus followed by an infusion of ropivacaine 0.