Effect of Clonidine and Bupivacaine in Intrathecal Versus Peripheral Nerve Block Routes in Arthroscopic Knee Surgery: Prospective Observational Study

Abstract Background and Aims: A large number of patients undergoing arthroscopic knee surgeries complain of inadequate pain relief. Clonidine and bupivacaine were administered through intrathecal route and femorosciatic nerve block route and evaluated for more favourable perioperative outcome between them. Methods: An open label randomized controlled trial was planned in a tertiary care hospital in Eastern India in which 50 American Society of Anaesthesiologists I and II patients undergoing arthroscopic knee surgery were enrolled. They were divided into two groups-Group IT and Group NB, by using computer-generated block randomization technique. Group IT received 1 μg/kg of clonidine along with 0.5% hyperbaric bupivacaine, whereas Group NB received 0.25% bupivacaine and 1 μg/kg clonidine in femorosciatic nerve block (FSNB). Postoperative pain-free interval and block characteristics were the primary outcomes studied. Results: Pain-free duration was 522.08(±21.18) min in Group NB (P < 0.001) in comparison to 325.33(±17.85) min in Group IT. Sensory block and motor blockade in NB were 469.58(± 15.17) and 264.88(±14.87) min, respectively, and was significantly prolonged in comparison to Group IT (P < 0.001). The mean rescue analgesic requirement was less in Group NB as compared to Group IT. Conclusion: Clonidine in a dose of 1 μg/kg with bupivacaine has better perioperative outcome through FSNB route in comparison to its use via intrathecal route in arthroscopic knee surgery. It provided stable haemodynamic and respiratory parameters intra and postoperatively, increased duration of sensory block and pain-free period, lesser 24 h rescue analgesic requirement making it ideal for post knee surgery pain.