Ultrasound-guided dexmedetomidine combination with modified high fascia iliaca compartment block for arthroscopic knee surgery: what is the optimal dose of dexmedetomidine?

Abstract

BackgroundTotal knee arthroplasty (TKA) is a common orthopedic procedure for end-stage knee osteoarthritis. Although effective in relieving pain and improving function, postoperative pain is still a common and distressing problem for many patients. This study aims to investigate efficacy of combined administration of dexmedetomidine and modified high fascia iliaca compartment block (H-FICB) in managing acute and chronic pain after TKA, as well as to identify the optimal dosage of dexmedetomidine.MethodsA double-blind, randomized controlled trial was conducted to evaluate the effects of dexmedetomidine in patients undergoing TKA. A total of 96 patients undergoing TKA were randomly assigned to one of three groups, were treated with different doses of dexmedetomidine All groups received H-FIB. Pain scores, opioid consumption, side effects, and quality of life were recorded 48 h postoperatively.ResultsThe intraoperative consumption of remifentanil and propofol in Group Db was significantly reduced compared with that in Group D0 and Da (P < 0.05). Compared with D0 and Da group, Db group had the lowest number of rescue analgesia, analgesia time and morphine accumulative dosage 48 h after operation (P < 0.05). The Db group had the lowest scores on the numerical rating scale at rest (P < 0.05) and during movement (P < 0.01), followed by the Da group and then the D0 group. Additionally, the incidence of nausea and vomiting was significantly reduced in the Db group (P < 0.05). Furthermore, the Db group had the lowest incidence of chronic pain (P < 0.05).DiscussionIn comparison to the other two groups, the administration of combined dexmedetomidine and H-FIB resulted in a significant reduction in pain scores, opioid consumption, and side effects. The optimal dosage of dexmedetomidine was determined to be 1 μg/kg, which provided the most favorable pain relief with minimal adverse effects.