Efficacy of intraoperative intravenous lidocaine for postoperative analgesia following bariatric surgery: a meta-analysis of randomized controlled studies

Dosing optimisation of intravenous lidocaine in patients with class 1-3 obesity by population pharmacokinetic analysis

INTRODUCTION

Evidence to support intra-operative lidocaine infusion regimens in patients with obesity is lacking, risking underdosing or toxicity. We aimed to measure the plasma concentrations of lidocaine and its active metabolites to develop a pharmacokinetic model and optimised dosing regimen in patients with obesity.

METHODS

A standardised weight-based intravenous lidocaine regimen was administered to patients with a BMI ≥ 30 kg.m-2 undergoing elective laparoscopic abdominal surgery. Using lean body weight, a 1.5 mg.kg-1 loading dose over 10 min and infusion of 1.5 mg.kg-1.h-1 was administered intra-operatively. Arterial blood was sampled during and after the infusion. The total and unbound plasma concentrations of lidocaine, monoethylglycinexylidide and glycinexylidide were measured using liquid chromatography-mass spectrometry. Monolix was used for population pharmacokinetic analysis. Dosing simulations were performed using Simulx to develop a regimen that best targeted a therapeutic plasma concentration between 2.5 and 5 μg.ml-1.

RESULTS

Thirty patients provided 221 plasma samples (median (IQR [range]) age 51 (44-61 [32-76]) y and 21 female). Median (IQR [range]) total body weight was 107.0 (91.8-132.5 [80.0-189.0]) kg and BMI was 37.7 (33.6-46.5 [30.2-58.4]) kg.m-2. Using total and unbound plasma concentrations of lidocaine, monoethylglycinexylidide and glycinexylidide, a four-compartment model was developed. Unbound lidocaine volume of distribution was 2.1 l.kg-1 and clearance 1.7 l.kg-1.h-1. Simulations showed that doses used currently had a low probability of target attainment of 0%. A loading dose of 2 mg.kg-1 over 20 min followed by an infusion of 3 mg.kg-1.h-1 based on lean body weight improved probability of target attainment to 18.6%. The infusion should be reduced to 2 mg.kg-1.h-1 after 80 min.

DISCUSSION

Our simulated dosing regimen achieved therapeutic concentrations more successfully in patients with obesity. Further studies should evaluate the clinical safety and efficacy of this dosing regimen.

Efficacy of Erector Spinae Plane Block on Analgesic Outcomes in Patients Undergoing Metabolic Surgery: A Meta-Analysis of Randomized Controlled Trials

This meta-analysis evaluated the analgesic efficacy of erector spinae plane block (ESPB) in metabolic surgery through analysis of ten randomized controlled trials (786 patients). ESPB demonstrated superior pain control compared to placebo from 2-12 h postoperatively, with peak effect at 6 h and sustained movement-related pain reduction through 24 h. ESPB showed comparable analgesic efficacy to other nerve blocks within 24 h postoperatively. The technique significantly reduced intraoperative and postoperative opioid consumption, extended time to first analgesic requirement, and decreased rescue analgesia needs. Additionally, ESPB recipients experienced reduced postoperative nausea and vomiting and shorter hospital stays. These findings support ESPB as an effective component of multimodal analgesia protocols for metabolic surgery, though standardization of techniques and long-term outcome studies are needed.

Efficacy of nonopioid analgesics and adjuvants in multimodal analgesia for reducing postoperative opioid consumption and complications in obesity: a systematic review and network meta-analysis

BACKGROUND

Managing postoperative pain in patients with obesity is challenging. Although multimodal analgesia has proved effective for pain relief, the specific impacts of different nonopioid i.v. analgesics and adjuvants on these patients are not well-defined. This study aims to assess the effectiveness of nonsteroidal antiinflammatory drugs, paracetamol, ketamine, α-2 adrenergic receptor agonists, lidocaine, magnesium, and oral gabapentinoids in reducing perioperative opioid consumption and, secondarily, in mitigating the occurrence of general and postoperative pulmonary complications (POPCs), nausea, vomiting, PACU length of stay (LOS), and hospital LOS among surgical patients with obesity.

METHODS

A systematic review and network meta-analysis was performed. PubMed, Scopus, Web of Science, CINAHL, and EMBASE were searched. Only English-language RCTs investigating the use of nonopioid analgesics and adjuvants in adult surgical patients with obesity were included. The quality of evidence and certainty were assessed using the RoB 2 tool and GRADE framework, respectively.

RESULTS

In total, 37 RCTs involving 3602 patients were included in the quantitative analysis. Compared with placebo/no intervention or a comparator, dexmedetomidine, ketamine, lidocaine, magnesium, and gabapentin significantly reduced postoperative opioid consumption after surgery. Ketamine/esketamine also significantly reduced POPCs. Ibuprofen, dexmedetomidine, and lidocaine significantly reduced postoperative nausea, whereas dexmedetomidine, either alone or combined with pregabalin, and lidocaine reduced postoperative vomiting. Dexmedetomidine significantly reduced PACU LOS, whereas both paracetamol and lidocaine reduced hospital LOS.

CONCLUSIONS

Intravenous nonopioid analgesics and adjuvants are crucial in multimodal anaesthesia, reducing opioid consumption and enhancing postoperative care in adult surgical patients with obesity.

SYSTEMATIC REVIEW PROTOCOL

CRD42023399373 (PROSPERO).

Intravenous lidocaine for postoperative analgesia management in paediatrics: A systematic review with meta-analysis of published studies

BACKGROUND

The administration of intravenous lidocaine during the peri-operative period may improve pain management after paediatric surgery.

OBJECTIVE

To explore the decrease in postoperative pain intensity and opioid consumption associated with peri-operative lidocaine administration in the paediatric population.

DESIGN

A systematic review with meta-analysis of randomised controlled trials and a Grading of Recommendations Assessment, Development and Evaluation (GRADE) analysis.

DATA SOURCES

Extensive literature review.

ELIGIBILITY CRITERIA

This study includes clinical trials conducted during surgery that examined the effect of intravenous lidocaine compared with placebo on postoperative pain management.

RESULTS

Lidocaine administration decreased pain intensity in PACU (standardised mean difference (SMD) = -1.89 [-3.75, -0.03], I2  = 97%, P of I2  < 0.001) and on postoperative day 1 (SMD = -2.02 [-3.37, -0.66], I2  = 96%, P of I2  < 0.001, number of studies = 5). Lidocaine was associated with a decrease in opioid consumption on postoperative day 1 (SMD = -1.2 [-2.19, -0.2], I2  = 93%, P of I2  < 0.001) but not on postoperative day 2 (SMD = -1.73 [-3.9, 0.44], I2  = 96%, P of I2  < 0.001). GRADE analyses resulted in low-quality results. Subgroup analyses revealed that pain intensity in PACU and opioid consumption on postoperative day 1 decreased when lidocaine was administered during both the intra-operative and postoperative periods.

CONCLUSIONS

The use of lidocaine is associated with improved pain management. However, further studies are needed to increase the level of evidence and determine the optimal administration regimen for pain management.

Intraoperative application of low-dose dexmedetomidine or lidocaine for postoperative analgesia in pediatric patients following craniotomy: a randomized double-blind placebo-controlled trial

Background

Postoperative pain is a common occurrence in pediatric patients following craniotomy, often leading to negative outcomes. Intravenous dexmedetomidine and lidocaine are commonly used adjuvant medicines in general anesthesia to reduce perioperative opioid consumption and relieve postoperative pain in adults. While they show promise for use in pediatrics, the evidence of their application in pediatric craniotomy patients is limited. Therefore, we aimed to compare the effects of dexmedetomidine and lidocaine on postoperative pain in pediatric patients following craniotomy.

Methods

We conducted a randomized, double-blind, single-center trial on children scheduled for craniotomy. The 255 recruited participants aged 1-12 years were randomly assigned to intraoperatively receive a loading intravenous dose of either dexmedetomidine 1 μg·kg-1 or lidocaine 2 mg·kg-1 or normal saline for 15 min followed by dexmedetomidine 0.5 μg·kg-1·h-1 or lidocaine 1 mg·kg-1·h-1 or normal saline until the sutures of endocranium were completed. The primary outcome was the cumulative sufentanil consumption within 24 h post-surgery.

Results

A total of 241 patients were included in the statistical analysis. The primary outcome did not show any significant differences among the three groups (median (IQR) lidocaine group: 3.36 (1.32-5.64) μg vs. dexmedetomidine group: 3.12 (1.36-6.39) μg vs. control group 3.46 (1.77-7.62) μg, p = 0.485). Among the secondary outcomes, there was a statistically significant but small reduction in sufentanil consumption within 2 h, postoperative FLACC/WBFS/NRS pain scores within 4 h after surgery and postoperative Ramsay sedation scores in dexmedetomidine group (p < 0.05). Regarding postoperative complications, the incidence of electrolyte disturbance within 24 and 48 h after surgery was significantly higher in control group compared to the other two groups. There were no significant differences in intraoperative opioid consumption, postoperative frequency of remedy medication, or length of hospitalization among the three groups. No adverse events related to lidocaine or dexmedetomidine were observed.

Conclusions

There were no significant differences in the primary outcome among the three groups. Although dexmedetomidine showed some benefits in reducing postoperative opioid consumption within the first 2 h and pain intensity within the first 4 h post-surgery, these findings should be interpreted with caution. Further research is required to comprehensively assess the outcomes and determine the optimal administration strategy.

Clinical Trial Registration

[http://www.chictr.org.cn/index.aspx], identifier [ChiCTR1800019411].

Effects of intravenous lidocaine on postoperative pain and gastrointestinal function recovery following gastrointestinal surgery: a meta-analysis

INTRODUCTION

The full extent of intravenous lidocaine's effectiveness in alleviating postoperative pain and enhancing gastrointestinal function recovery remains uncertain.

EVIDENCE ACQUISITION

We conducted an exhaustive search of databases to identify randomized controlled trials that compared intravenous lidocaine infusion's efficacy to that of a placebo or routine care in patients undergoing gastrointestinal surgery. The primary outcome measure was resting pain scores 24 h postoperatively. We utilized a random-effects model based on the intention-to-treat principle for the overall results.

EVIDENCE SYNTHESIS

This study included twenty-four trials with 1533 patients. Intravenous lidocaine significantly reduced resting pain scores 24 h after gastrointestinal surgery (twenty trials, SMD -0.67, 95% CI -1.09 to -0.24, P=0.002, I2 = 90%). This finding was consistent in subgroup analyses and sensitivity analyses. The benefit was also observed at other resting and moving time points (1, 2, 4, and 12 h) postoperatively. Intravenous lidocaine significantly decreased opioid consumption within 24 h after surgery (eleven trials, SMD: -1.19; 95% CI: -1.99 to -0.39; P=0.003). Intravenous lidocaine also shortened the time to bowel sound (MD: -8.51; 95% CI: -14.59 to -2.44; P=0.006), time to first flatus (MD: -6.00; 95% CI: -9.87 to -2.13; P=0.002), and time to first defecation (MD: -9.77; 95% CI: -17.19 to -2.36; P=0.01).

CONCLUSIONS

Perioperative intravenous lidocaine can alleviate acute pain and expedite gastrointestinal function recovery in patients undergoing gastrointestinal surgery. However, the results should be interpreted with caution due to substantial heterogeneity. Further large-scale studies are necessary to validate these findings.

Non-Opioid Analgesics and Adjuvants after Surgery in Adults with Obesity: Systematic Review with Network Meta-Analysis of Randomized Controlled Trials

Background/Objectives: Managing postoperative pain in patients with obesity is challenging. Although using a combination of pain relief methods is recommended for these patients, the true effectiveness of various intravenous non-opioid analgesics and adjuvants in multimodal anesthesia needs to be better defined. Methods: A systematic review and network meta-analysis was performed to evaluate the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, ketamine, α-2 agonists, lidocaine, magnesium, and oral gabapentinoids in adult surgical patients with obesity. The analysis aimed to compare these treatments to a placebo/no treatment or alternative analgesics, with a primary focus on postoperative pain and secondary endpoints including rescue analgesia, postoperative nausea and vomiting (PONV), and recovery quality. English-language randomized controlled trials across PubMed, Scopus, Web of Science, CINAHL, and EMBASE were considered. Quality and evidence certainty were assessed with the RoB 2 tool and GRADE, and data was analyzed with R software. Results: NSAIDs, along with acetaminophen, lidocaine, α-2 agonists, ketamine, and oral gabapentinoids, effectively reduce early postoperative pain. NSAIDs, particularly ibuprofen, as well as acetaminophen, ketamine, and lidocaine, also show benefits in later postoperative stages. Intravenous non-opioid analgesics and adjuvants show some degree of benefit in reducing PONV and the need for rescue analgesic therapy when using α-2 agonists alone or combined with oral gabapentinoids, notably decreasing the likelihood of PONV. Ketamine, lidocaine, and α-2 agonists are shown to enhance postoperative recovery and care quality. Conclusions: Intravenous non-opioid analgesics and adjuvants are valuable in multimodal anesthesia for pain management in adult surgical patients suffering from obesity.

Systemic Anti-Inflammatory Effects of Intravenous Lidocaine in Surgical Patients: A Systematic Review and Meta-Analysis

There has recently been increasing evidence that the use of perioperative intravenous lidocaine infusion possesses analgesic, opioid-sparing and anti-inflammatory effects in surgical patients. Although opioid-sparing and analgesic properties have been strongly supported, the anti-inflammatory features are not well established in elective surgery. Therefore, the aim of this systematic review is to examine the effect of perioperative intravenous lidocaine infusion on postoperative anti-inflammatory status in patients undergoing elective surgery. A search strategy was created to identify suitable randomised clinical trials (RCTs) in PubMed, Scopus, Web of Science and Clinicaltrials.gov databases until January 2023. RCTs that evaluated the effect of intravenous lidocaine infusion, compared with placebo, on adult patients who underwent elective surgery, in inflammatory markers response were included. Exclusion criteria consisted of paediatric patients, animal studies, non-RCT methodology, intervention without intravenous lidocaine, inadequate control group, duplicated samples, ongoing studies and lack of any relevant clinical outcome measures. The following inflammatory markers-interleukin (IL)-6, tumour necrosis factor (TNF)-α, IL-1RA, IL-8, IL-10, C-reactive protein (CRP), IL-1, IL-1β, interferon (IFN)-γ, cortisol, IL-4, IL-17, high-mobility group protein B1 (HMGB1) and transforming growth factor (TGF)-β-were evaluated as outcomes in this review. A total of 21 studies, including 1254 patients, were identified. Intravenous lidocaine infusion significantly reduced the change from IL-6 baseline levels at the end of surgery compared to a placebo (standardised mean difference [SMD]: -0.647, 95% confidence interval [CI]: -1.034 to -0.260). Usage of lidocaine was associated with a significant reduction in other postoperative pro-inflammatory markers, such as TNF-α, IL-1RA, IL-8, IL-17, HMGB-1 and CRP. There was no significant difference in other markers, such as IL-10, IL-1β, IL-1, IFN-γ, IL-4, TGF-β and cortisol. This systematic review and meta-analysis provide support for the administration of perioperative intravenous lidocaine infusion as an anti-inflammatory strategy in elective surgery.

Impact of Opioid-Free Anesthesia on Analgesia and Recovery Following Bariatric Surgery: a Meta-Analysis of Randomized Controlled Studies

This meta-analysis aimed at exploring the impact of opioid-free anesthesia (OFA) on pain score and opioid consumption in patients undergoing bariatric surgery (BS). Literature search identified eight eligible trials. Forest plot revealed a significantly lower pain score (mean difference (MD) =  - 0.96, p = 0.0002; 318 patients), but not morphine consumption (MD =  - 5.85 mg, p = 0.1; 318 patients) at postoperative 24 h in patients with OFA than in those without. Pooled analysis also showed a lower pain score (p = 0.002), morphine consumption (p = 0.0003) in the postanesthetic care unit, and risk of postoperative nausea/vomiting (p = 0.0003) in the OFA group compared to the controls. In conclusion, this meta-analysis demonstrated that opioid-free anesthesia improved pain outcomes immediately and at 24 h after surgery without a beneficial impact on opioid consumption at postoperative 24 h. KEY POINTS: • Roles of opioid-free anesthesia (OFA) in bariatric surgery (BS) were investigated. • Outcomes included postoperative pain score, opioid use, and nausea/vomiting risk. • OFA was associated with lower 24-h pain score but not opioid consumption. • Lower pain score and opioid consumption were noted in the postanesthetic care unit. • OFA correlated with a lower risk of postoperative nausea/vomiting.

Effect of intravenous lidocaine on pain after head and neck cancer surgery (ELICO trial): A randomised controlled trial

BACKGROUND

Treatment of postoperative pain after ear, nose and throat (ENT) cancer surgery is mainly morphine administration. Additional systemic lidocaine has shown promising results in some surgical procedures.

OBJECTIVE

The main objective was to evaluate morphine consumption in the first 48 postoperative hours after intra-operative lidocaine infusion during major ENT cancer surgery.

DESIGN

A randomised, double-blind, placebo-controlled trial.

SETTING

Bicentric study including a university hospital and a major cancer centre, conducted from December 2016 to December 2019.

PATIENTS

A total of 144 patients undergoing major ENT cancer surgery were included.

INTERVENTION

The patients were randomly assigned to receive intravenous lidocaine or placebo during surgery and in the recovery room.

MAIN OUTCOME MEASURES

Endpoints were postoperative morphine consumption in the first 24 and 48 h postoperatively, intra-operative remifentanil consumption, adverse events occurrence and assessment 3 to 6 months after surgery with the McGill pain questionnaire.

RESULTS

A total of 118 patients were included (lidocaine n  = 57; placebo n  = 61, 26 patients were excluded). There was no significant difference in morphine consumption during the first 48 postoperative hours in the lidocaine group compared with the placebo group with a median [IQR] of 0.60 [0.30 to 1.03] mg kg -1 vs. 0.57 [0.37 to 0.96] mg kg -1 , total dose 44 [21 to 73.3] mg vs. 38 [23.3 to 56.5] mg, P  = 0.92.There was no significant difference between the two groups in any of the other endpoints, including at follow up 3 to 6 months after surgery.

CONCLUSION

Intravenous lidocaine in ENT cancer surgery did not show any additional analgesic or morphine-sparing effect 48 h after surgery. Three to six months after surgery, there was no significant difference in pain scores or consumption of analgesics. Patients treated pre-operatively with opioids were not evaluated in the study.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02894710 and EUDRACT number 2015-005799-90.

Analgesic Efficacy of Gabapentin and Pregabalin in Patients Undergoing Laparoscopic Bariatric Surgeries: a Systematic Review and Meta-analysis

This meta-analysis investigated the effect of oral gabapentinoids (i.e., pregabalin and gabapentin) on analgesic consumption (i.e., primary outcome) and pain relief (i.e., secondary outcome) in patients following bariatric surgery. Analysis of five eligible trials published between 2010 and 2019 including 363 participants receiving gabapentinoids revealed a significantly lower morphine consumption [mean difference (MD) =  - 15.1 mg, p = 0.004; evidence certainty: low] and risk of nausea/vomiting [risk ratio (RR) = 0.49, p = 0.002; evidence certainty: high] at postoperative 6-24 h. There was also a lower pain score at postoperative 0-4 h (MD =  - 1.41, p < 0.00001; evidence certainty: low) and 6-12 h (MD =  - 0.9, p = 0.007; evidence certainty: low) compared with controls, while pain severity at postoperative 24 h was comparable between two groups. In summary, preoperative oral gabapentinoids optimized postoperative pain outcomes and reduced risk of nausea/vomiting following bariatric surgery.