Abstract
Intravenous (IV) dexmedetomidine is reported to prolong analgesia following peripheral nerve blocks. Popliteal sciatic nerve block provides effective postoperative analgesia, but some patients still experience severe pain during the early postoperative period. We aimed to evaluate the postoperative analgesic effects of IV dexmedetomidine versus propofol in patients undergoing foot surgeries under popliteal sciatic nerve block. Forty patients were enrolled and randomly assigned to receive either IV propofol (n = 20) or IV dexmedetomidine (n = 20) for intraoperative sedation. All the patients received continuous popliteal sciatic nerve block. The corresponding drug infusion rate was adjusted to achieve a modified observer’s assessment of alertness/sedation score of 3 or 4. The primary outcome was postoperative cumulative opioid consumption during the first 24 h after surgery. Thirty-nine patients were analyzed. The median (interquartile ranges) postoperative cumulative opioid consumption during the first 24 h after surgery was significantly lower in the dexmedetomidine group (15 (7.5–16.9) mg) than in the propofol group (17.5 (15–25) mg) (p = 0.019). The time to first rescue analgesic request was significantly greater in the dexmedetomidine group than in the propofol group (11.8 ± 2.2 h vs. 10.0 ± 2.7 h, p = 0.030) without the prolonged motor blockade (p = 0.321). Intraoperative sedation with dexmedetomidine reduced postoperative opioid consumption and prolonged analgesic duration after a popliteal sciatic nerve block.
Highlights
Major foot surgery is associated with moderate to severe postoperative pain [1]
From November 2018 to December 2019, 44 patients scheduled for major foot surgery under popliteal sciatic nerve block were assessed for eligibility, and four patients who did not meet the inclusion criteria were excluded (Figure 2)
One patient allocated to the propofol group was excluded after receiving the popliteal sciatic nerve block, because the surgical plan was changed to bilateral feet, and the anesthetic plan was changed to general anesthesia
Summary
Continuous popliteal sciatic nerve block with perineural local anesthetic infusion has emerged as an efficient component of acute pain management after various foot surgeries. Continuous popliteal sciatic nerve block has many benefits, including effective postoperative analgesia, reduced opioid consumption, and improved patient satisfaction [2,3,4,5], a significant number of patients still experience severe pain during the first 24 h after surgery [4]. Intravenous (IV) dexmedetomidine as a sedative for surgery under regional anesthesia has been studied widely because it produces the unconsciousness similar to that of natural sleep without respiratory depression [7], and reduces postoperative pain and opioid consumption [8,9]. More recent studies assessed the effect of dexmedetomidine as an intraoperative sedative drug on the analgesic duration under spinal anesthesia [8,9], but the evidence of its efficacy on popliteal sciatic nerve block is still lacking
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
