Mahmut Durmus, Mukadder Sanli, Erdogan Ozturk, Aytac Yucel, Nurcin Gulhas, M. Ozcan Ersoy

Effects of Adding Dexmedetomidine to Amitriptyline on Sciatic Nerve Blockadge in Rats

Abstract Neurotoxic effects of amitriptyline which is a tricyclic antidepressant limit its use as a local anesthetic. In this study, comparing the effect of combination of different amitrptyline doses with dexmedetomidine on block initiation and termination time in sciatic nerve blockadge with amitrptyline and bupivacaine alone was aimed. A total of 42 male Sprague-Dawley rats were divided into groups with 7 rats in each. These groups were randomly divided into 6 groups as amitriptyline 0.625 mg (Group 1), amitriptyline 0.312 mg (Group 2), dexmedetomidine 10 Î¼g (Group 3), amitriptyline 0.625 mg and dexmedetomidine 10 Î¼g (Group 4), amitriptyline 0.312 mg and dexmedetomidine 10 Î¼g (Group 5), bupivacaine 0.5% (Group 6). In the right arm with posterior approach, 0.2 mL of local anesthetic was injected with lateral incision . Effectiveness of local anesthetic was determined in terms of motor function, proprioseptive, nosiseptive sensation. In our study, amitriptyline and combination of amitrpityline-dexmedetomidine showed longer local anesthetic effect compared to bupivacaine. Mean block initiation times were shorter in bupivacaine group compared to amitriptyline group though it was not statistically significant. Adding 10 Î¼g of dexmedetomidine to 0.625 mg amitriptyline prolonged block termination times significantly compared to 0.625 mg amitriptyline alone (p<0.05). In this study, combination of amitriptyline and dexmedetomidine was shown to prolong block time in peripheral nerve blockadge and aditive interaction generated in increased doses was shown to be able to be more. Adding dexmedetomidine was detected to delay block initiation times.

Keywords:

Sciatic Nerve Blockadge, Amitriptyline, Dexmedetomidine, Bupivacaine,

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