Clinical, electrophysiological and histopathological effect of insulin on the sciatic nerve block created with bupivacaine in rabbits under sevofluran anesthesia

Aim: In this study; We aimed to demonstrate clinically, electrophysiologically and histopathologically the effects of insulin, which is preferred to eliminate the negative effects of long-acting local anesthetics by shortening the duration of action, and shortens the effect times of local anesthetics, on sciatic nerve blockade in rabbits administered sevoflurane anesthesia. Materials and Methods: The right hind extremity sciatic nerve of 32 New Zealand male rabbits was studied. 0.7 ml saline in Group 1 (Control, Sham), 0.5 U/kg insulin (0.7 ml) in Group 2 (Insulin), 0.5 mg/kg in Group 3 (Bupivacaine) bupivacaine (0.7 mL) and in Group 4 (Bupivacaine+Insulin) 0.5 mg/kg bupivacaine + 0.5 U/kg insulin (0.7 ml) was injected. Paw pulling response was monitored and recorded every 30 minutes after skin closure in all groups. Hot-plate test was used. Computer-assisted electrophysiological responses were recorded. In addition, samples were taken on the 1st and 14th days to examine the tissue histopathology. Results: Significant differences were found at 0th, 30th and 60th minutes in terms of Claw Pull Test sensory block, and at all time periods in terms of Claw Pull Test motor block. It was determined that the scores in Group 3 in terms of Claw Pull Test motor block were significantly different from the other groups. According to electrophysiological measurements, insulin has been shown to reduce the effect of bupivacaine. In histological evaluation, it was determined that fibrillary degeneration seen in the bupivacaine group was significantly reduced in the bupivacaine+insulin group. Conclusion: We have shown that insulin reduces the nerve blockage caused by bupivacaine clinically and electrophysiologically and may have positive contributions on tissue healing. Keywords: bupivacaine, insulin, sciatic block, sevoflurane, rabbit