Related Experiment Video
Updated: Apr 17, 2026

Preparation, Procedures and Evaluation of Platelet-Rich Plasma Injection in the Treatment of Knee Osteoarthritis
Published on: January 4, 2019
Ropivacaine plasma levels following high-dose local infiltration analgesia for total knee arthroplasty
A S Brydone1, R Souvatzoglou2, M Abbas3
1Department of Orthopaedic Surgery, Golden Jubilee National Hospital, Glasgow, UK.
Abstract:
We measured total and free plasma concentrations of ropivacaine following high-volume, high-dose local infiltration analgesia in 28 patients aged 65 years or over undergoing unilateral total knee arthroplasty. Patients received infiltration of ropivacaine 400 mg followed by infusion at 20 mg.h(-1) through an intra-articular catheter. Total and free plasma levels of ropivacaine were measured at specified time intervals during a 24-h period after tourniquet release. Patients were monitored for symptoms and signs of local anaesthetic toxicity. Total levels of plasma ropivacaine varied from 0.147 to 3.093 μg.ml(-1) (mean (SD) 1.105 (0.518) μg.ml(-1) ). Free levels of plasma ropivaca-ine varied from 0.001 to 0.104 μg.ml(-1) (mean (SD) 0.037 (0.020) μg.ml(-1) ). Six samples had total plasma ropivacaine levels greater the toxic threshold of 2.2 μg.ml(-1) . No samples reached the toxic threshold for free venous ropivacaine concentration. We conclude that the use of high-dose ropivacaine infiltration and catheter infusion for total knee arthroplasty in an elderly population does not result in free plasma ropivacaine levels previously associated with toxicity but that raised total plasma levels may be observed.
Related Concept Videos
Local Anesthetics: Clinical Application as Intravenous Regional Anesthesia
One of the advantages of...
Local Anesthetics: Clinical Application as Epidural Anesthesia
Since epidural anesthetics can be infused through an epidural catheter, all types of drugs, including short-acting ones, can be administered. Chloroprocaine and lidocaine are examples of short and long-duration anesthetics, respectively. Bupivacaine...
Local Anesthetics: Pharmacokinetics
Local Anesthetics: Clinical Application as Spinal Anesthesia
Local Anesthetics: Adverse Effects
Once absorbed into the systemic circulation, local anesthetics can affect the organs that depend on the functioning of sodium...
Local Anesthetics: Clinical Application as Surface, Infiltration, and Conduction Block Anesthesia

