Evaluation of the effects of bupivacaine combined with sugammadex on the duration of the nociceptive blockade in sciatic nerve blocks: a controlled, double-blind animal study

Background Animal and other experimental studies have demonstrated increased block time and quality when alpha and beta cyclodextrin drugs are combined with the local anesthetic. However, to our knowledge there exists no study that has utilized gamma cyclodextrins in such a combination. In this present study we used an animal model to evaluate the effect of different doses of combined administration of gamma cyclodextrin (sugammadex) and bupivacaine on sciatic nerve blockage times in rats. Methods Sciatic block was performed with 0.20 mL mixture in all groups. This mixture consisted of 0.2ml saline in the Sham group, 0.2ml sugammadex in Group S and 0.16ml bupivacaine 0.5% and 0.04ml saline in Group B. In the experimental groups, in addition to 0.16ml bupivacaine 0.5%, 0.01 ml sugammadex and 0.03ml saline was added in Group BS1 0.02ml sugammadex and 0.02ml saline was added in Group BS2 and 0.04ml sugammadex was added in Group BS4. Proprioception, nociception and motor function was evaluated until sciatic block was completely reversed. Results Motor, proprioceptive and nociceptive block occurred in all experimental groups within 5 minutes. In Group BS4 the duration of motor, proprioceptive and nociceptive blocks significantly increased compared with other experimental groups. However in Group BS1 and Group BS2, only the duration of nociceptive block significantly increased. Conclusion Combined administration of sugammadex and bupivacaine when performing sciatic nerve block in rats leads to a significant prolongation of motor, proprioceptive and nociceptive block times.