Junsung Lim

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1. Introduction Opioid-induced hyperalgesia (OIH) is a condition in which the long-term use of high doses of opioids results in pain sensitization. Paradoxically, a painful stimulus with the same intensity may result in even more intense pain. OIH can cause delays in discharge and discomfort due to higher pain scores and increased use of analgesics and their related effects [1]. Remifentanil is a type of ultra-short-acting μ opioid receptor agonist that is commonly used in general anesthesia.

4. Discussion This meta-analysis of eight RCTs, including 802 patients (of whom 399 patients underwent PNBs and 403 patients underwent SA), demonstrated that the block performance time, onset of sensory and motor blocks, and duration of sensory and motor blocks were significantly shorter, the postoperative analgesics requirements were higher, and the SBP at 30 min was significantly lower in the SA group than in the PNB group.