Safety and analgesic efficacy of intravenous dexmedetomidine in arthroscopic knee surgery

CONTEXT: Dexmedetomidine, a highly selective alpha-2 agonist has been used as an adjuvant analgesic in vascular, bariatric, and thoracic surgery. We assessed the efficacy of intravenous dexmedetomidine as an analgesic adjunct to local anesthetic infiltration for control of postoperative pain in arthroscopic knee surgery. SETTINGS AND DESIGN: This was a randomized control study performed in a Tertiary Care Hospital. MATERIALS AND METHODS: Forty-five adult patients scheduled for anterior/posterior cruciate ligament reconstruction were randomized into three groups. Group B (bupivacaine group) received bupivacaine intraarticularly and normal saline by the intravenous route. Group D (dexmedetomidine group) received Intravenous dexmedetomidine and normal saline intraarticularly. Group BD (bupivacaine + dexmedetomidine group) received a combination of intravenous dexmedetomidine and intraarticular bupivacaine. Patient's cardiorespiratory parameters, time to first rescue, total rescue analgesic consumption in first 24 h, visual analog scale for pain were assessed. STATISTICAL ANALYSIS: The data were analyzed using analysis of variance and Chi-square test. RESULTS: The time to first request for rescue analgesia was significantly prolonged in Group D and Group BD patients (P < 0.05) compared to Group B. Total rescue analgesic consumption was least in Group BD. Group D and Group BD patients had lower heart rate and systolic and diastolic blood pressure values. CONCLUSION: Intravenous dexmedetomidine in combination with intraarticular bupivacaine decreased perioperative analgesic requirement in patients undergoing arthroscopic knee surgery. However, monitoring and vigilance are essential if dexmedetomidine is used as part of a multimodal analgesic regimen in view of its hemodynamic side effects.