A Systematic Review and Meta-analysis of the Analgesic Effects of Lidocaine Administered Intravenously or Intraperitoneally Post-Abdominal Surgery

BACKGROUND

Reducing postoperative pain is still a tremendous challenge for perioperative clinicians. Lidocaine is a local anesthetic that belongs to the amide class and has anti-inflammatory, anti-hyperalgesic, and analgesic effects. Extensive research has been conducted to determine the optimal route for its administration.

OBJECTIVE

To compare the efficacy of perioperative intravenous lidocaine with that of intraperitoneal lidocaine on postoperative analgesia in patients undergoing abdominal surgery.

STUDY DESIGN

EMBASE, PubMed, and The Cochrane Library were searched for randomized controlled trials published through December 2022 that compared patients receiving perioperative intravenous lidocaine with those receiving intraperitoneal lidocaine. The primary outcome measures included the pain score, as evaluated by the Visual Analog Scale, and opioid analgesia requirements. The secondary outcome measures were hospitalization length, gastrointestinal function recovery, etc. The data were acquired and recorded in electronic spreadsheets that had been designed for this purpose.

METHODS

This systematic review's design was based on the Cochrane Handbook for Systematic Reviews of Interventions and was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) method was used to examine the certainty of the evidence. Furthermore, we examined the dependability of the calculated (favorable) treatment effects through considerations of information size and modified significance thresholds (trial sequential analysis).

RESULTS

Seven trials including 478 patients were included. Our meta-analysis demonstrates that compared with intravenous lidocaine, patients who received intraperitoneal lidocaine had lower pain scores at 4 hours (mean difference [MD] 1.40; 95% CI, 0.22 to 2.59); 12 hours (MD 0.18; 95% CI, 0.06 to 0.30); and 24 hours (MD -0.12; 95% CI -0.40 to 0.17) postsurgery. However, no obvious difference in opioid consumption (P > 0.05) was found. In addition, the intraperitoneal lidocaine group had a longer postsurgery hospital stay than the intravenous lidocaine group (95%CI, -0.17 to -0.00; I2 = 0%). Intravenous lidocaine was more beneficial for achieving gastrointestinal return than intraperitoneal lidocaine (95% CI, -0.26 to -0.10; I2 = 2%).

LIMITATIONS

The sample size of enrolled RCTs was small, which could potentially result in an overestimation or underestimation of the treatment effect in the collected data. There was high heterogeneity among the studies.

CONCLUSION

This meta-analysis suggests that post-abdominal surgery intraperitoneal lidocaine administration has a better analgesic effect than intravenous lidocaine, with a lower pain score. However, intravenous lidocaine is more beneficial for gastrointestinal recovery after abdominal surgery.

Effect of S-ketamine on Postoperative Pain in Adults Post-Abdominal Surgery: A Systematic Review and Meta-analysis

BACKGROUND

S-ketamine is the S-enantiomer of ketamine, which exerts anesthetic and analgesic effects through noncompetitive antagonism of N-methyl-D-aspartate (NMDA) receptors.

OBJECTIVE

We aimed to define the relative risk of post-abdominal surgery pain in adults who were administered perioperative S-ketamine.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

Two reviewers independently screened the articles from the titles and abstracts based on our eligibility criteria, evaluated the risk of bias by using the Cochrane Collaboration Risk of Bias tool in randomized controlled trials, and extracted the data from the included studies according to a prespecified protocol; any disagreements were solved by consultation. The level of certainty for the main results were evaluated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.

RESULTS

Of the 1,621 studies identified, 9 studies were included; they were published from 2004 through 2022. Only one study involved epidural anesthesia, whereas the other 8 studies included general anesthesia. The pain at rest scores at 4 and 24 hours post-abdominal surgery were significantly lower in the S-ketamine group, respectively. However, there was no significant difference between the 2 groups in the pain at rest scores at 48 hours post-abdominal surgery. S-ketamine infusion reduced pain during movement 24 hours post-abdominal surgery, but not at 48 hours, respectively. The incidence of postoperative nausea and vomiting, as well as psychotomimetic adverse effects post-abdominal surgery were similar between the 2 groups, respectively. A subgroup analysis revealed that the pain at rest score at 4 hours post-abdominal surgery in patients in the intraoperative use group was remarkably reduced, compared with the patients who received S-ketamine perioperatively. Otherwise, the pain at rest score at 24 hours post-abdominal surgery in the perioperative use group was significantly reduced versus intraoperative use group.

LIMITATION

The number of trials included was small. The remarkable heterogeneity found in the pooled results at each time point post-abdominal surgery might affect the credibility of the results.

CONCLUSIONS

S-ketamine is effective in reducing the early postoperative pain of patients who received abdominal surgery, and may not increase the incidence of postoperative complications.