Introduction: Main goal of nerve blockade is to provide analgesia that will outlast duration of pain as long as possible. Deficiency of currently available local aneasthetics is relatively short duration of action. The aim of this study was to compare sensory and motor blockade after perineural application of liposomal bupivacaine, ropivacaine or lidocaine with addition of dexamethasone during peripheral nerve blockade in Wistar rats. Materials and methods: A rat sciatic nerve block model was used. The study was conducted in accordance with the principles of laboratory animal care and was approved by the Laboratory Animal Care and Use Committee. Thirty adult Wistar rats both sexes were studied. After induction of general anesthesia, and sciatic nerve was exposed unilaterally. Sciatic nerves were randomly assigned by the method of sealed envelopes to recive: 2 mL perineurally 1.33% liposomal bupivacaine, 1% ropivacaine or a solution of 2% lidocaine with addition of 4mg / ml of dexamethasone. Neurologic examination protocol was followed to determine motor function by extensor postural thrust and nociception by withdrawal reflex. Results: The rate of recovery of motor and sensory function after perineural administration of liposomal bupivacaine is statistically slower compared (<0.001) with perineural administration of ropivacaine or lidocaine with addition of dexamethasone. Liposomal bupivacaine significantly prolonged analgesic effect when used as a single – injection perineural sciatic block. Conclusion: Liposomal bupivacaine has a favorable profile when it comes to the duration of ation compared with lidocaine in combination with dexamethasone and ropivacaine.
