Preemptive Epidural Analgesia for Postoperative Pain Relief Revisited: Comparison of Combination of Buprenorphine and Neostigmine with Combination of Buprenorphine and Ketamine in Lower Abdominal Surgeries, A Double-blind Randomized Trial

ED90 of epidural esketamine with 0.075% ropivacaine for labor analgesia in nulliparous parturients: a prospective, randomized and dose-finding study

Background: Because it has been reported that racemic ketamine had a local anesthetic-sparing effect when used for epidural analgesia this would suggest the likelihood of a potential advantage (less pruritus) over opioid drugs. Esketamine has greater analgesic efficacy than racemic ketamine, but the optimum dosage regimen for epidural use is undetermined. The aim of this study was to determine the ED₉₀ of epidural esketamine when coadministered with 0.075% ropivacaine for labor analgesia. Methods: A total of 65 laboring nulliparous patients were enrolled in this study from 16 March 2022 to 15 October 2022. The patients were randomly assigned to receive 0, 0.25, 0.5, 0.75 or 1.0 mg/mL esketamine with 0.075% ropivacaine epidurally. An effective response to the epidural loading dose was defined as numerical rating scale pain score ≤3 at 30 min after the end of the epidural loading dose (10 mL of the ropivacaine 0.075% solution with the added esketamine). The ED₉₀ of epidural esketamine coadministered with 0.075% ropivacaine with 95% confidence intervals for labor analgesia was determined using probit regression. Secondary outcomes and side effects were recorded. Results: The estimated value of ED₉₀ with 95% CIs for epidural esketamine with 0.075% ropivacaine was 0.983 (0.704-2.468) mg/mL. The characteristics of sensory and motor block, consumption of ropivacaine per hour, duration of first or second stage, Apgar scores did not differ among the five groups. The incidence of mild dizziness in Group esketamine 1.0 mg/mL was significantly higher than that in other groups (p < 0.05). No statistical differences were found in other side effects among groups. Conclusion: The ED₉₀ value of epidural esketamine coadministered with 0.075% ropivacaine for labor analgesia in nulliparous parturients was about 1.0 mg/mL. Furthermore, our results suggested that epidural esketamine would cause dose-dependent mild dizziness especially at doses up to 1.0 mg/mL. As a single epidural additive, esketamine may not be suitable for labor analgesia. Future studies may investigate the appropriate dosage of esketamine at slightly higher concentrations of local anesthetics or larger initial volume of analgesia, or explore other potential advantages of esketamine. Clinical Trial Registration: (https://www.chictr.org.cn/bin/project/edit?pid=159764), identifier (ChiCTR2200057662).

Analgesic effect of preoperative dezocine-based local anesthesia in patients undergoing inguinal hernia repair

Objective

This study was performed to investigate the analgesic effects of intramuscular injection of dezocine-based local anesthesia in patients undergoing inguinal hernia repair.

Methods

A total of 120 patients underwent local herniorrhaphy from July 2015 to December 2016 and were randomly divided into 2 groups: the dezocine group, in which a preoperative intramuscular injection of dezocine was administered, and the control group, in which no dezocine injection was administered. The patients’ pain and comfort levels were evaluated at 30 minutes, 2 hours, 6 hours, 12 hours, and 24 hours postoperatively.

Results

The visual analog scale scores at 30 minutes, 2 hours, 6 hours, 12 hours, and 24 hours were significantly lower in the dezocine than control group. In the Bruggemann comfort scale evaluation, patients who received dezocine injections showed significantly greater comfort than those in the control group at 30 minutes, 2 hours, 6 hours, 12 hours, and 24 hours. No adverse reactions occurred in the dezocine group.

Conclusions

Dezocine-based local anesthesia can attenuate postoperative pain and increase the comfort level during and after herniorrhaphy.