A double-blind randomized study on the toxicity of lidocaine and ropivacaine on sciatic nerve and biceps muscle of rats

Abstract

The purpose of the study was to examine the damaging activity of Lidocaine and Ropivacaine on the sciatic nerve and biceps muscle of rats. A double blind randomized study was conducted. The control group received injectiona of 0.9% NaCl. The following concentrations of Lidocaine were examined – 0.5, 1, 1.5, and 2. For Ropivacaine, these concentrations were 0.25, 0.5, 0.75, and 1. Under the US control, 0.2 ml were injected along the perineural sciatic nerve and 0.2 ml into the two-headed muscle. The drugs were taken out in 1 hour after their injection. When injecting 0.9% NaCl no cell necrosis or apoptosis in the muscle and nerve were found, only single cells of inflammatory type were found. The administration of all concentrations of local anesthetics caused inflammatory filtration and damage to muscle tissue and nerve stems compared to 0.9% NaCl. Increased expression of damage and inflammatory infiltration depended on the concentration of the local anesthetic. The higher the concentration of Lidocaine or Ropivacaine was, the greater were the damage and inflammatory changes. The study demonstrated neurotoxic and miotoxic activity of all concentrations of Lidocaine and Ropivacaine compared to 0.9% NaCl. The dependence of damage strengthening and the growth of inflammatory filtration in the muscle and peripheral nerve on the increased concentration of the local anesthetic was revealed.

Keywords

• albino rat
• bupivacaine
• lidocaine
• local anesthetic
• myotoxicity
• neurotoxicity
• skeletal muscles
• sciatic nerve