Background And Objectives: Ropivacaine is the S(-) propyl homolog of bupivacaine and mepivacaine. Studies in humans have confirmed the results of studies in laboratory animals that ropivacaine is a long-acting local anesthetic with an anesthetic profile similar to bupivacaine. Acute, intravenous systemic toxicity studies have been conducted in sheep and dogs. Local anesthetic efficacy has been studied after epidural administration in the dog. This study was initiated to determine the local anesthetic efficacy and pharmacokinetics of ropivacaine and bupivacaine after epidural administration in an experimental sheep model and to evaluate the sheep model as a model of experimental epidural anesthesia.
Methods: Twelve adult nonpregnant ewes were prepared with chronically implanted lumbar epidural catheters and arterial lines. Each sheep received injections of 5.0 mL ropivacaine and bupivacaine (0.5% and 0.75%) in a blinded, random, cross-over fashion. Onset and duration of sensory and motor blockade were evaluated. Arterial blood samples were drawn for serum drug concentration determinations and pharmacokinetic analysis.
Results: Onset and duration of motor blockade were similar for comparable concentrations of both drugs. Both concentrations of ropivacaine and bupivacaine 0.5% demonstrated differential neural blockade. The peak serum concentrations generally occurred within 8 minutes after administration. The terminal elimination half-life in serum was about 3.5-4.0 hours and 6 hours for ropivacaine and bupivacaine, respectively. No signs of systemic toxicity were observed. Results of sensory and motor blockade were consistent with previous studies in laboratory animals and humans.
Conclusions: Ropivacaine produces sensory and motor blockade which is similar to that produced by equal concentrations of bupivacaine after epidural administration in the sheep. Peak serum concentrations produced no signs of systemic toxicity. The results of this study are consistent with previously published data from studies in laboratory animals and humans. The sheep model of experimental epidural anesthesia appears to be a clinically relevant method to evaluate experimental local anesthetics.
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http://dx.doi.org/10.1016/s1098-7339(97)80033-8 | DOI Listing |
Clin Drug Investig
January 2025
Cali Biosciences, US, LLC, San Diego, CA, USA.
Background And Objective: There is a significant medical need for improved long-acting local anesthetics to decrease postsurgical pain and reduce postoperative opioid use. While ropivacaine is considered a safer local anesthetic than bupivacaine, no long-acting ropivacaine formulation is currently marketed. Available formulations of bupivacaine show inconsistent pharmacokinetics (PK) among different surgical models, and inconsistency in PK may lead to a reluctance to use the medication owing to fear of local anesthetic systemic toxicity (LAST) or unreliable efficacy.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Biochemistry, National Defense Medical Center, Taipei 114, Taiwan.
Local anesthetics are commonly used in various clinical settings for both prevention and symptom relief. Numerous clinical studies have demonstrated that intra-articular injections of local anesthetics achieve high success rates in orthopedic practices. However, several widely used local anesthetics, including bupivacaine, lidocaine, and ropivacaine, have been shown to exhibit toxicity to chondrocytes, with the underlying mechanisms of chondrotoxicity remaining poorly understood.
View Article and Find Full Text PDFCurr Pain Headache Rep
January 2025
Department of Anesthesiology, Perioperative, and Pain Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA.
Purpose Of Review: The rhomboid intercostal and subserratus plane (RISS) block is an effective, safer alternative for managing postoperative acute pain following abdominal surgeries. The RISS block offers several advantages over traditional approaches, including reduced incidence of puncture-related complications, lower rates of systemic opioid consumption, and more consistent analgesic coverage of lower thoracic dermatomes.
Recent Findings: Despite a favorable safety profile, the RISS block carries potential risks, such as pneumothorax and local anesthetic systemic toxicity, particularly when long-acting anesthetics such as bupivacaine or ropivacaine are used.
Drug Des Devel Ther
December 2024
Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian, People's Republic of China.
Purpose: Intrathecal morphine is increasingly used for pain management in laparoscopic colorectal surgery. While ropivacaine shows advantages of reduced cardiotoxicity and faster motor recovery compared to bupivacaine, the impact of intrathecal morphine-ropivacaine combination on postoperative recovery quality remains unclear. This study aimed to evaluate this combination's effect on recovery outcomes after laparoscopic colorectal surgery.
View Article and Find Full Text PDFAnesth Analg
December 2024
From the Department of Anesthesiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin Province, China.
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