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.

Comparison Between Two Volumes of 70% Alcohol in Single Injection Ultrasound-Guided Celiac Plexus Neurolysis: A Randomized Controlled Trial

BACKGROUND

Pain due to inoperable upper abdominal malignancies is a challenging condition that needs a multimodal analgesic regimen to be managed properly. Celiac plexus alcohol neurolysis was proved to be effective in relieving such type of pain; however, there is no consistent data about the optimal volume to be used to maintain the balance between the neurolytic effect and the destructive effect of alcohol.

OBJECTIVES

We aim to compare the analgesic effect of 2 different volumes of alcohol to improve the outcome of interventional management.

STUDY DESIGN

This was a randomized controlled double-blinded interventional clinical trial.

SETTING

Single university hospital.

METHODS

Thirty-two patients who suffered from abdominal pain due to unresectable abdominal malignancies were randomly allocated to receive in a single injection ultrasound-guided celiac plexus neurolysis (CPN) with injection of either 20 mL 70% alcohol (CPN20 group) or 40 mL 70% alcohol (CPN40 group). The primary outcome was the post-procedure pain score, while the secondary outcomes included the post-procedure total daily opioid consumption and quality of life (QOL).

RESULTS

There was no statistically significant difference between both groups regarding visual analog scale (VAS) scores at all time points (P-value > 0.05); however, comparisons in each group revealed significantly reduced VAS scores at all time points following the intervention when compared to the baseline. Daily morphine equivalent consumption doses showed statistically significant differences between the baseline and each time point in both groups (P value < 0.05), with no significant difference between both groups at each time point (P value > 0.05). There was no statistically significant difference between the study groups regarding all domains in quality of life assessment at all time points (P value > 0.05). The scores of most time points in all domains were different significantly when compared to the baseline readings in both groups, with a tendency to decline over time in both groups approaching the baseline values.

LIMITATIONS

This was a single-center study with a relatively small sample size. Further prospective, multicenter, randomized, and controlled studies with a larger sample size are required to confirm the effects in this study.

CONCLUSIONS

During ultrasound-guided CPN for patients with inoperable upper abdominal cancers who failed medical management, a volume of 20 mL is as effective as 40 mL of 70% alcohol regarding pain control, opioid consumption, quality of life, and procedure-related complications.

Effects of Intravenous Dexmedetomidine Versus Lidocaine on Postoperative Pain, Analgesic Consumption and Functional Recovery After Abdominal Gynecological Surgery: A Randomized Placebo-controlled Double Blind Study

BACKGROUND

The management of acute postoperative pain remains challenging, and the search for adjuvants to reduce opioid use continues.

OBJECTIVES

We studied the effect of intravenous dexmedetomidine and lidocaine on postoperative pain, opioid consumption, and functional recovery.

STUDY DESIGN

A randomized controlled trial was performed.

SETTING

The trial was conducted at Aretaieio University Hospital, Athens, Greece.

METHODS

In this double-blind study, 91 women, 30-70 years old, with an American Society of Anesthesiologists Physical Status of I or II, scheduled for abdominal hysterectomy or myomectomy, were randomized to receive either dexmedetomidine (DEX group), lidocaine (LIDO group), or placebo (CONTROL group). Before anesthesia induction, a loading intravenous dose of one of the aforementioned drugs was given to all patients (0.9mL/kg/h for 10 minutes), followed by 0.15mL/kg/h infusion until the last suture. Identical 50 mL syringes containing dexmedetomidine 4 mg/mL (bolus: 0.6 µg/kg, infusion: 0.6 µg/kg/h), or lidocaine 10 mg/mL (bolus: 1.5 mg/kg, infusion: 1.5 mg/kg/ h), or NaCl 0.9% were used. The main outcomes were cumulative morphine consumption and postoperative pain at rest and cough (Numeric Rating Scale, [NRS]: 0-10). Other measurements included anesthetic (sevoflurane) consumption, nausea/vomiting, postoperative sedation, time to first passage of flatus/stool, mobilization, sleep quality, satisfaction, discharge time, and drug side effects. Measurements were performed at Post-anesthesia Care Unit (PACU), 2 hours, 4 hours, 8 hours, 24 hours, and 48 hours.

RESULTS

Data from 81 patients were analyzed (DEX group:26, LIDO group:29, CONTROL group:26). Cumulative morphine consumption (mg) was significantly lower in the LIDO group versus the CONTROL group in the PACU (LIDO group: 8.41 ± 1.45, CONTROL group: 10.4 ± 3.29, P = 0.017); at 24 hours (LIDO group: 16.86 ± 5.85, CONTROL group: 23.4 ± 9.54, P = 0.036); and 48 hours (LIDO group: 20.45 ± 6.58, CONTROL group: 28.87 ± 12.55, P = 0.022). The DEX group experienced significantly less nausea compared to the CONTROL group in the PACU (P = 0.041). Finally, the use of vasoconstrictors was higher in the treatment groups, especially in the DEX group compared to the CONTROL group (P = 0.012). The rest of the measurements regarding NRS scores, sevoflurane consumption, bowel function, and other recovery characteristics, satisfaction, discharge time, and drug side effects did not differ significantly among the groups.

LIMITATIONS

Different doses of the studied medications were not assessed, drugs were administered only pre- and intraoperatively, and pain was not managed according to the World Health Organization (WHO) pain relief ladder. However, all patients were adequately covered with patient-controlled anesthesia morphine and acetaminophen; parecoxib (not approved for use in the United States) was preserved as a rescue analgesic.

CONCLUSIONS

Dexmedetomidine and lidocaine could be useful adjuvants for analgesia after abdominal surgery. Lidocaine significantly reduced postoperative opioid consumption, while dexmedetomidine prevented early postoperative nausea. However, hypotension and the need for vasopressors was common with both agents, especially with dexmedetomidine.