Effects of perineural administration of phenytoin in combination with levobupivacaine in a rat sciatic nerve block

Abstract

Öz:Peripheral nerve blocks are commonly preferred worldwide for the purposes of anesthesia application and postoperative analgesia. In this study, we investigated the effects of phenytoin which has a similar mechanism to local anesthetics in terms of the duration of analgesia and quality. The study was performed on 32 Sprague-Dawley male rats. Rats were randomly grouped into 4 groups. Group S: Sham group (n: 8); 0,2 ml saline perineural unilateral sciatic nerve. Group L: Perineural levobupivacaine (0,2 ml 0,5% levobupivacaine, n: 8); Group Ph: Perineural phenytoin (0,2 ml 62,5 mg / kg, n: 8); Group L + PH: Perineural phenytoin and levobupivacaine (0,2 ml 0,5% levobupivacaine + 62,5 mg / kg phenytoin, n: 8). Hot-plate and tail- flick tests were performed to measure acute thermal pain and histological changes were evaluated. The latency time at 30 minute in Group L+Ph were significantly increased when compared to the other groups during evaluation of the hot plate test. There was a significant difference in terms of latency time at 30 minute in Group L+Ph in the Tail Flick test and the latency time in Group L+Ph was longer when compared to the other groups (p<0,05) These results were obtained according to hot-plate and tail-flick tests and indicated that the analgesic quality. Perineural administration of phenytoin in combination with levobupivacaine did not affect the duration of the sensory and motor blockade at doses used in our study. However, phenytoin combined with levobupivacaine increased the duration and quality of the analgesia.