Effect of Local Anesthetics on Postoperative Pain in Patients Undergoing Gynecologic Laparoscopy: A Systematic Review and Meta-analysis of Randomized Trials

The impact of timing, type, and method of instillation of intraperitoneal local anaesthetic in laparoscopic abdominal surgery: a systematic review and network meta-analysis

BACKGROUND

Pain is common after laparoscopic abdominal surgery. Intraperitoneal local anaesthetic (IPLA) is effective in reducing pain and opioid use after laparoscopic surgery, although the optimum type, timing, and method of administration remains uncertain. We aimed to determine the optimal approach for delivering IPLA which minimises opioid consumption and pain after laparoscopic abdominal surgery.

METHODS

MEDLINE, Embase, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were systematically searched for randomised controlled trials comparing different combinations of the type (bupivacaine vs lidocaine vs levobupivacaine vs ropivacaine), timing (pre-vs post-pneumoperitoneum at the beginning or end of surgery), and method (aerosol vs liquid) of IPLA instillation in patients undergoing any laparoscopic abdominal surgery. A network meta-analysis was conducted to ascertain the optimum approach for delivering IPLA resulting in the least cumulative opioid consumption and pain (overall and localising to the shoulder) 24 h after surgery. Certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) assessments (PROSPERO ID: CRD42022307595).

RESULTS

Twenty-five RCTs were included, among which 15 different combinations of delivering IPLA were analysed across 2401 participants. Aerosolised bupivacaine instilled at the end of surgery, before deflation of the pneumoperitoneum, was associated with significantly less postoperative opioid consumption compared with all other approaches for delivering IPLA (98.7% of comparisons; moderate certainty), aside from liquid levobupivacaine instilled before surgery and during or after creation of the pneumoperitoneum (mean difference -11.6, 95% credible interval: -26.1 to 2.5 i.v. morphine equivalent doses). There were no significant differences between different IPLA approaches regarding overall pain scores and incidence of shoulder pain up to 24 h after surgery.

CONCLUSIONS

There are limited studies and low-quality evidence to conclude on the optimum method of delivering IPLA in laparoscopic abdominal surgery. While aerosolised bupivacaine instilled at the end of surgery but before deflation of the pneumoperitoneum minimises postoperative opioid consumption, pain scores up to 24 h did not differ between the different modalities of delivering IPLA. The generalisability of these results is limited by the lack of utilisation of non-opioid analgesics in most trials.

SYSTEMATIC REVIEW PROTOCOL REGISTRATION

PROSPERO CRD42022307595.

Liposomal Bupivacaine Injection for Analgesia During Minimally Invasive Supracervical Hysterectomy

Objective

To evaluate the efficacy of intracervical injection of liposomal bupivacaine for postoperative pain control among women undergoing minimally invasive supracervical hysterectomy.

Methods

A randomized double-blinded placebo-controlled trial of intracervical injection of combination liposomal bupivacaine and bupivacaine for postoperative pain among patients undergoing laparoscopic and robotic supracervical hysterectomy. Patients were enrolled between October 1, 2018 and April 30, 2019. The primary outcome was pain at 12 hours postoperatively using a numeric rating scale from zero to 10. Pain scores were also recorded pre-operatively, immediately postoperatively, at 12, 24, and 48 hours postoperatively. The secondary outcome was the number of patients who required opioid analgesic medications up to 48 hours postoperatively.

Results

Sixty participants were randomized into the control (n = 30) and intervention (n = 30) groups. Pain scores were 1 and 1.75 (p = 0.89) immediately postoperatively, 3 and 3.5 (p = 0.85) at 12 hours, 3.5 and 5 (p = 0.22) at 24 hours, and 2.75 and 4 (p = 0.18) at 48 hours for the control and intervention groups, respectively. Within the first 24 hours, 10 patients in the control and 14 patients in the intervention group used narcotics (p = 0.37). From the 24 to 48 hours window, 6 and 8 patients in the control and intervention groups used narcotics (p = 0.74), respectively.

Conclusion

There was no statistically significant difference in pain scores between patients receiving combination liposomal bupivacaine and bupivacaine intracervical block and those receiving placebo in the first 48 hours after surgery. There was no difference in analgesic use between the two study groups.