Ropivacaine

Effective postoperative pain management remains a cornerstone of enhanced recovery protocols following total knee arthroplasty (TKA). Inadequate analgesia not only compromises patient satisfaction but also impedes early mobilization and rehabilitation, thereby increasing the risk of perioperative complications. Current multimodal analgesic strategies frequently incorporate regional techniques, with the adductor canal block (ACB) and infiltration between the popliteal artery and capsule of the knee (IPACK) block emerging as established modalities that provide motor-sparing analgesia. Despite their widespread adoption, the optimal local anesthetic regimen for these blocks remains undefined. While liposomal bupivacaine has garnered interest for its extended duration of action, its clinical efficacy relative to conventional local anesthetics combined with perineural adjuncts remains a subject of ongoing debate. Specifically, perineural dexamethasone and dexmedetomidine have each demonstrated the capacity to prolong the analgesic duration of ropivacaine; however, direct comparative data among these three distinct strategies-liposomal bupivacaine alone versus ropivacaine supplemented with either adjunct-are notably limited. Given the absence of head-to-head randomized trials evaluating these three clinically viable techniques, the optimal approach to maximize analgesic duration while minimizing opioid-related adverse effects remains unclear. This study therefore aims to compare the analgesic efficacy and safety profiles of liposomal bupivacaine, ropivacaine with perineural dexamethasone, and ropivacaine with perineural dexmedetomidine when administered via ACB and IPACK blocks in patients undergoing TKA.

With the changes in medical models and improvements in people's quality of life, parturients have higher demands for childbirth, making the alleviation and elimination of labor pain an important aspect of modern obstetrics. Intrathecal labor analgesia has been widely adopted in clinical practice to relieve pain. However, current studies mainly focus on parturients who are just beginning to receive labor analgesia, while for those experiencing prolonged analgesia, medical institutions still use traditional formulations, lacking relevant guidelines or expert consensus. In such cases, prolonged waiting and anxiety may lower the pain tolerance of parturients, leading to an increased need for higher concentrations of local anesthetics. To address this clinical gap, this study aims to explore the effects of different concentrations of ropivacaine in prolonged labor analgesia and has designed a prospective randomized controlled trial (RCT) to provide evidence for improving the analgesic regimen for this group of parturients.

The goal of this pilot clinical trial is to test the feasibility of conducting a randomized controlled trial that will examine the use of ropivacaine in the spinal anesthesia for patients undergoing elective 1- or 2-level lower spine surgery. This study aims to: * Determine the rates of eligibility, recruitment, consent, and attrition * Determine the acceptability among patients, surgeons, anesthesiologists, and nurses of doing spine surgery under spinal anesthesia * Gather preliminary data on outcomes relevant to a future dose-finding study Participants will be randomized to one of three treatment groups: * General anesthesia with endotracheal tube * Spinal anesthesia with bupivacaine * Spinal anesthesia with ropivacaine