Randomized, Double-Blind Study of the Effect of Intraoperative Intravenous Lidocaine on the Opioid Consumption and Criteria for Hospital Discharge After Bariatric Surgery

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).

Effects of Intravenous Lidocaine on Quality of Recovery After Laparoscopic Bariatric Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This systematic review and meta-analysis aimed to assess the effects of pre and intraoperative lidocaine infusion on short-term recovery quality after laparoscopic bariatric surgeries. In the search across MEDLINE, Embase, and Cochrane databases, we considered randomized controlled trials comparing intravenous lidocaine vs placebo (saline) for patients with obesity undergoing laparoscopic bariatric surgery. Seven studies (640 patients) were included. The lidocaine group had a significantly higher recovery quality score, a lower morphine consumption, and a notably reduced rate of nausea and vomiting compared with the placebo group. Additionally, Lidocaine infusion was associated with a shorter hospital stay, while no significant difference was observed in the time to bowel function recovery between both groups. In conclusion, lidocaine infusion before and during laparoscopic bariatric surgery contributes to an enhanced quality of recovery.

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.

Opioid-Free Anesthesia in Bariatric Surgery: Is It the One and Only? A Comprehensive Review of the Current Literature

Opioid-free anesthesia (OFA) is a heterogeneous group of general anesthesia techniques in which the intraoperative use of opioids is eliminated. This strategy aims to decrease the risk of complications and improve the patient's safety and comfort. Such potential advantages are particularly beneficial for selected groups of patients, among them obese patients undergoing laparoscopic bariatric surgery. Opioids have been traditionally used as an element of balanced anesthesia, and replacing them requires using a combination of coanalgesics and various types of local and regional anesthesia, which also have their side effects, limitations, and potential disadvantages. Moreover, despite the growing amount of evidence, the empirical data on the superiority of OFA compared to standard anesthesia with multimodal analgesia are contradictory, and potential benefits in many studies are being questioned. Additionally, little is known about the long-term sequelae of such a strategy. Considering the above-mentioned issues, this study aims to present the potential benefits, risks, and difficulties of implementing OFA in bariatric surgery, considering the current state of knowledge and literature.

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.

Guidelines on perioperative optimization protocol for the adult patient 2023

OBJECTIVE

The French Society of Anesthesiology and Intensive Care Medicine [Société Française d'Anesthésie et de Réanimation (SFAR)] aimed at providing guidelines for the implementation of perioperative optimization programs.

DESIGN

A consensus committee of 29 experts from the SFAR was convened. A formal conflict-of-interest policy was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence.

METHODS

Four fields were defined: 1) Generalities on perioperative optimization programs; 2) Preoperative measures; 3) Intraoperative measures and; 4) Postoperative measures. For each field, the objective of the recommendations was to answer a number of questions formulated according to the PICO model (population, intervention, comparison, and outcomes). Based on these questions, an extensive bibliographic search was carried out using predefined keywords according to PRISMA guidelines and analyzed using the GRADE® methodology. The recommendations were formulated according to the GRADE® methodology and then voted on by all the experts according to the GRADE grid method. As the GRADE® methodology could have been fully applied for the vast majority of questions, the recommendations were formulated using a "formalized expert recommendations" format.

RESULTS

The experts' work on synthesis and application of the GRADE® method resulted in 30 recommendations. Among the formalized recommendations, 19 were found to have a high level of evidence (GRADE 1±) and ten a low level of evidence (GRADE 2±). For one recommendation, the GRADE methodology could not be fully applied, resulting in an expert opinion. Two questions did not find any response in the literature. After two rounds of rating and several amendments, strong agreement was reached for all the recommendations.

CONCLUSIONS

Strong agreement among the experts was obtained to provide 30 recommendations for the elaboration and/or implementation of perioperative optimization programs in the highest number of surgical fields.

Analgesic efficacy of systemic lidocaine using lean body mass based dosing regime versus placebo in bariatric surgery: a prospective, randomised, double-blinded, placebo-controlled, single centre study

BACKGROUND

Intravenous lidocaine is used as an adjuvant analgesic agent in perioperative settings. It has been investigated in various patient populations and surgical interventions, but there are limited data on its efficacy, particularly for patients undergoing bariatric surgery. Obese patients are at high risk of postoperative respiratory complications and can be expected to benefit from anaesthetic techniques that minimise opioid administration.

METHODS

We studied administration of lidocaine hydrochloride 1% i.v. to general anaesthesia at a dose of 1.5 mg kg^-1 (lean body mass×1.28) or placebo in patients undergoing bariatric surgery. Subjects randomly assigned to each group were surveyed for 48 h after surgery for experienced pain (primary outcome), and administered opioids, postoperative nausea and vomiting (PONV), resumption of bowel function, and length of hospital stay (secondary outcomes).

RESULTS

We recruited and randomised 140 subjects to either the lidocaine or placebo group; 137 completed the study. Subjects with pain numeric rating scale (NRS) >3 within the first 4 h postoperatively were similar in both groups (proportion of any NRS >3 within first 4 h lidocaine group: 47/68 (69%) vs placebo group: 44/69 (63%), P=0.507; within first h P=0.177, within second h P=0.513, within third h P=0.145, within fourth h P=0.510). There was no difference in maximal pain score, opioid consumption, recovery of bowel function, incidence of PONV, or length of hospital stay.

CONCLUSIONS

Lidocaine does not improve postoperative pain scores, analgesia, or any secondary outcomes in patients undergoing bariatric surgery.

CLINICAL TRIAL REGISTRATION

NCT03667001.

Intravenous lidocaine infusion compared to thoracic epidural analgesia in cytoreductive surgery with or without heated intraperitoneal chemotherapy. A retrospective case-cohort study

BACKGROUND

Intravenous (IV) lidocaine is a proven analgesic therapy but has not been evaluated in extensive procedures such as cytoreductive surgery (CRS). Our aim was to assess the effectiveness and safety of IV lidocaine in this setting.

METHODS

This is a retrospective hybrid case-cohort study investigating analgesic effectiveness and complications of perioperative IV lidocaine at 1.5 mg/kg/h for 48 h compared to thoracic epidural anaesthesia (TEA) among patients undergoing CRS in a high-volume centre.

RESULTS

Sixty patients were included, 20 received IV lidocaine and 40 underwent TEA. Pain scores were low (median ≤2) and similar in both groups (p = 0.88). At 72 h, the lidocaine group had a lower median pain score (p = 0.03). Overall opioid consumption in the first 48 h was lower in the lidocaine compared to the TEA group (median 0 (IQR 0-9.5) mg vs. 45.4 (0-62.4) MME respectively, p = 0.001). Opioid consumption was also lower in the lidocaine compared to the TEA group during the whole 5-day period (median 1 (IQR 1-13.5) mg vs. 112 (36.6-137.85) MME respectively, p = 0.000). The incidence of PONV was significantly lower in the lidocaine group (27.5% vs 5%, p = 0.047) with no difference in other complications or length of in-hospital stay.

CONCLUSION

Intravenous lidocaine infusion may be a safe and effective analgesic approach in CRS and is associated with a significant reduction of opioid use and PONV compared to opioid-containing TEA.

Ultrasound-guided erector spinae plane block for postoperative analgesia in Chinese patients undergoing laparoscopic cholecystectomy: a double-blind randomized controlled trial

PURPOSE

Pain management after laparoscopic cholecystectomy (LC) is a main concern for Chinese clinicians. This study aims to explore the effect of erector spinae plane block (ESPB) on the postoperative analgesia of patients undergoing LC in China.

METHODS

In this randomized controlled trial (RCT), 220 patients were randomized into the ESPB group and control group. Patients in the ESPB group received a bilateral ESPB, and patients in the control group were injected saline. Lornoxicam (0.08 mg/mL, 100 mL) was used as routine analgesia for both groups after the surgery. Visual analog scale (VAS) score at rest state at 12 h postoperative was the primary outcome and divided into no pain, mild pain, moderate pain, and severe pain.

RESULTS

Finally, 197 patients were included for analysis. At postoperative 12 h, ESPB group observed less patients with moderate pain (0% vs. 8.91%) and severe pain (0% vs. 0.99%) than the control group (P < 0.001). Moreover, ESPB group found less dose of additional sufentanil (5.55 ± 1.37 μg vs. 10.67 ± 5.05 μg), less requirement for rescue analgesia (13.54% vs. 31.68%), earlier first time to leave bed (10 h vs. 18 h), and earlier first exhaust time (17.5 h vs. 25 h), less adverse reactions (5.21% vs. 17.82%), and higher satisfaction degree (78.13% vs. 31.68%) (all P < 0.05).

CONCLUSIONS

ESPB was followed by better postoperative analgesia and less opioid consumption.

Comparison of Ketamine, Dexmedetomidine and Lidocaine in Multimodal Analgesia Management Following Sleeve Gastrectomy Surgery: A Randomized Double-Blind Trial

PURPOSE

The aim of this study was to compare the effects of ketamine, dexmedetomidine, and lidocaine infusions added to the multimodal analgesia regimen on pain scores and analgesic requirement in laparoscopic sleeve gastrectomy.

DESIGN

A prospective randomized double-blind trial. Seventy-three patients aged 18 to 65 years (ASA II-III) undergoing laparoscopic sleeve gastrectomy were included. The patients were divided into 3 groups. Intravenous (IV) ketamine (0.5 mg/kg/h), dexmedetomidine (0.5 mcg/kg/h), and lidocaine (2 mg/kg/h) were administered to Groups K, D and L, respectively. Postoperative infusions were continued for 12 hours.

METHODS

Visual Analog Scale (VAS) scores (during rest and movement) in the admission to postanesthesia care unit, 1, 3, 6, 12, 24, 48 hours, and on day 15 were assessed postoperatively. Rescue analgesia requirement, the number of patients with nausea, retching, and vomiting, time to mobilization, and hospital length of stay (LOS) were recorded.

FINDINGS

VAS_rest values during all measurements in the first 24 hours, and VAS_movement values in the first 6 hours and at 24 hours were lower in Group L when compared to Group K and Group D (P < .001, P < .001, P = .008, respectively). VAS_rest at 48 hours and VAS_movement at 12 and 48 hours were lower in Group L when compared to Group K (P = .044, P = .001 and P = .011, respectively). There was no statistically significant difference between Group D compared to the other two groups at these times (P > .05). The requirement of rescue analgesia on postoperative day 1 was significantly higher in Group K (P < .001). Hospital LOS was shorter in Group L than in the other groups (P = .002).

CONCLUSIONS

IV lidocaine added to multimodal analgesia provided better pain control in the early postoperative period compared to dexmedetomidine and ketamine and decreased the hospital LOS.

Effect of Ultrasound-Guided Transversus Abdominis Plane Block Combined with Patient-Controlled Intravenous Analgesia on Postoperative Analgesia After Laparoscopic Cholecystectomy: a Double-Blind, Randomized Controlled Trial

PURPOSE

To compare the effect of ultrasound-guided transversus abdominis plane block (TAPB) combined with patient-controlled intravenous analgesia (PCIA) and PCIA alone on analgesia after laparoscopic cholecystectomy (LC).

METHODS

In this double-blind, randomized controlled trial, 160 patients undergoing LC were randomized into the TAPB group (n = 80) and PCIA group (n = 80). Bilateral ultrasound-guided TAPB was performed with 20 mL 0.5% ropivacaine and the PCIA pump was given after LC in the TAPB group. The PCIA group received the PCIA pump alone as a control group. The primary outcome was postoperative pain, assessed by the visual analog scale (VAS).

RESULTS

VAS pain (including abdominal wall pain or visceral pain) scores at rest and coughing were significantly lower in the TAPB group at 1, 4, 12, 24, 36, and 48 h after LC (P < 0.05). Postoperative additional analgesic needs, analgesic pump compressions, and PCIA analgesic dosages, and total morphine equivalents were significantly reduced in the TAPB group, and postoperative hospital stay, total hospitalization expenses, expenses within 24 h or 48 h (from analgesia and adverse reactions), and patient satisfaction were significantly higher in the TAPB group than the PCIA group (all P < 0.05). No significant between-group differences were observed in operation time, intraoperative blood loss, unplugging the analgesic pump due to adverse reactions, first exhaust time, and postoperative adverse events between the two groups.

CONCLUSIONS

Ultrasound-guided TAPB combined with PCIA was an effective and safe perioperative analgesic technique for patients undergoing LC compared to PCIA only.

Anesthesia and Enhanced Recovery After Surgery in Bariatric Surgery

The Enhanced Recovery After Surgery Society published guidelines for bariatric surgery reviewing the evidence and providing specific care recommendations. These guidelines emphasize preoperative nutrition, multimodal analgesia, postoperative nausea and vomiting prophylaxis, anesthetic technique, nutrition, and mobilization. Several studies have since evaluated these pathways, showing them to be safe and effective at decreasing hospital length of stay and postoperative nausea and vomiting. This article emphasizes anesthetic management in the perioperative period and outlines future directions, including the application of Enhanced Recovery After Surgery principles in patients with extreme obesity, diabetes, and metabolic disease and standardization of the pathways to decrease heterogeneity.

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

BACKGROUND

The impact of intravenous lidocaine in adults undergoing laparoscopic bariatric surgeries (LBS) remains unclear.

OBJECTIVES

This study aimed at investigating the effect of intravenous lidocaine on postoperative opioid consumption and recovery following LBS.

SETTING

Meta-analysis.

METHODS

We searched databases including MEDLINE, Embase, Google Scholar, and the Cochrane Library for randomized controlled trials that evaluated the use of intravenous lidocaine compared to placebo only prior to May 2021. The primary outcome was 24-hour postoperative opioid consumption, while secondary outcomes included pain score, quality of recovery (QOR)-40 score, length of hospital stay (LOS), and postoperative nausea/vomiting (PONV).

RESULTS

Seven trials (496 participants) were included. Intraoperative intravenous lidocaine significantly reduced 24-hour equivalent morphine consumption (mean difference [MD]: -11.97 mg; 95% confidence interval [CI]: -23.12 to -.83), pain score at 1 to 3 hours (MD: -.77; 95% CI: -1.5 to -.04), and LOS (MD: -8.93 hr; 95% CI: -13.41 to -4.44) without positive impact on 24-hour pain score and PONV. There was also an increase in time to first opioid requirement (MD: 20.23 min; 95% CI: 11.76-28.7) and QOR-40 score (MD: 24.38; 95% CI: 5.57-43.18). However, sensitivity analysis demonstrated evidence supporting the beneficial effect of lidocaine only for time to first opioid requirement and QOR-40. The associations of intraoperative intravenous lidocaine with reductions in morphine consumption, pain score at 1 to 3 hours, and LOS after LBS were also weak.

CONCLUSION

Intraoperative intravenous lidocaine during LBS prolonged time to first opioid requirement and improved quality of recovery postoperatively without 24-hour pain or nausea/vomiting benefits. Due to the small number of trials, larger studies are warranted to verify our findings.

The effect of systemic lidocaine on post-operative opioid consumption in ambulatory surgical patients: a meta-analysis of randomized controlled trials

Background

Ambulatory surgical procedures continue to grow in relevance to perioperative medicine. Clinical studies have examined the use of systemic lidocaine as a component of multimodal analgesia in various surgeries with mixed results. A quantitative review of the opioid-sparing effects of systemic lidocaine in ambulatory surgery has not been investigated. The primary objective of this study was to systematically review the effectiveness of systemic lidocaine on postoperative analgesic outcomes in patients undergoing ambulatory surgery.

Methods

We performed a quantitative systematic review of randomized controlled trials in electronic databases (Cochrane Library, Embase, PubMed, and Google Scholar) from their inception through February 2019. Included trials investigated the effects of intraoperative systemic lidocaine on postoperative analgesic outcomes, time to hospital discharge, and adverse events. Methodological quality was evaluated using Cochrane Collaboration’s tool and the level of evidence was assessed using GRADE criteria. Data was combined in a meta-analysis using random-effects models.

Results

Five trials evaluating 297 patients were included in the analysis. The pooled effect of systemic lidocaine on postoperative opioid consumption at post-anesthesia care unit revealed a significant effect, weighted mean difference (95% CI) of − 4.23 (− 7.3 to 1.2, P = 0.007), and, at 24 h, weighted mean difference (95% CI) of − 1.91 (− 3.80 to − 0.03, P = 0.04) mg intravenous morphine equivalents. Postoperative pain control during both time intervals, postoperative nausea and vomiting reported at post anesthesia care unit, and time to hospital discharge were not different between groups. The incidence rate of self-limiting adverse events of the included studies is 0.007 (2/297).

Conclusion

Our results suggest that intraoperative systemic lidocaine as treatment for postoperative pain has a moderate opioid-sparing effect in post anesthesia care unit with limited effect at 24 h after ambulatory surgery. Moreover, the opioid-sparing effect did not impact the analgesia or the presence of nausea and vomiting immediately or 24 h after surgery. Clinical trials with larger sample sizes are necessary to further confirm the short-term analgesic benefit of systemic lidocaine following ambulatory surgery.

Trial registration

PROSPERO (CRD42019142229)

Supplementary Information

The online version contains supplementary material available at 10.1186/s13741-021-00181-9.

Intravenous Infusion of Lidocaine Can Accelerate Postoperative Early Recovery in Patients Undergoing Surgery for Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is defined by intermittent and recurrent episodes of partial or complete obstruction of the upper airway during sleep. Intermittent and recurrent hypoxia/reoxygenation is the main pathophysiological mechanism of OSA. Its consequences include systemic inflammation, activation of the sympathetic nervous system, and release of oxygen free radicals. Infusion of intravenous (IV) lidocaine has anti-inflammatory, antihyperalgesic, and analgesic properties, supporting its use as an anesthetic adjuvant. Lidocaine can reduce nociception and/or cardiovascular responses to surgical stress, as well as postoperative pain and/or analgesic requirements. Because of the high prevalence of OSA in obese patients, the use of opioids to manage postoperative pain in that population is often accompanied by the development of adverse respiratory events, such as hypoventilation and hypoxemia. IV infusion of lidocaine has been shown to enhance the quality of early recovery after laparoscopic bariatric and upper airway surgery. However, limited evidence exists regarding its use in patients undergoing surgery for OSA. In addition, whether IV infusion of lidocaine can improve postoperative early recovery in patients undergoing surgery for OSA remains unknown. Therefore, we hypothesized that IV infusion of lidocaine can improve postoperative early recovery in patients undergoing surgery for OSA. Perioperative infusion also may be a promising analgesic adjunct to enhanced recovery after surgery (ERAS) protocols.

Effect of intra-operative intravenous lidocaine on opioid consumption after bariatric surgery: a prospective, randomised, blinded, placebo-controlled study

Peri-operative lidocaine infusion warrants investigation in bariatric surgery because obese patients present different physiological and pharmacological risks. This single-centre, prospective, randomised double-blind placebo-controlled study enrolled obese patients scheduled for laparoscopic bariatric surgery using an enhanced recovery protocol. Patients received either lidocaine (bolus of 1.5 mg.kg^-1 , then a continuous infusion of 2 mg.kg^-1 .h^-1 until the end of the surgery, then 1 mg.kg^-1 .h^-1 for 1 h in the recovery area) or identical volumes and rates of 0.9% saline. The primary outcome was the consumption of the equivalent of oxycodone consumption over the first 3 postoperative days. Secondary outcomes were: postoperative pain; incidence of nausea and vomiting; bowel function recovery; and lengths of stay in the recovery area and in hospital. Plasma concentrations of lidocaine were measured. On the 178 patients recruited, data were analysed from 176. The median (IQR [range]) equivalent intravenous oxycodone consumption was 3.3 mg (0.0-6.0 [0.0-14.5]) and 5.0 mg (3.3-7.0 [3.3-20.0]) in the lidocaine and saline groups, respectively (difference between medians (95%CI): 1.7 (0.6-3.4) mg; p = 0.004). Length of stay in the recovery area, postoperative pain, nausea and vomiting, day of recovery of bowel function, and length of stay in hospital were not different between groups. Mean (SD) lidocaine plasma concentrations were 2.44 (0.70) µg.ml^-1 and 1.77 (0.51) µg.ml^-1 at the end of surgery and 1 hour after the end of infusion, respectively. Lidocaine infusion during bariatric surgery resulted in a clinically non-relevant difference in postoperative oxycodone consumption.

Assessment of the Effect of Perioperative Venous Lidocaine on the Intensity of Pain and IL-6 Concentration After Laparoscopic Gastroplasty

BACKGROUND AND OBJECTIVES

Opioids are associated with sedation and respiratory depression. The primary objective of this study was to assess pain intensity after gastric bypass with lidocaine. The secondary objective was to assess the IL-6 concentration, consumption of morphine, time to morphine request, time to extubation, and side effects.

METHODS

Sixty patients aged 18 to 60 years, with ASA (American Society of Anesthesiologists) scores of 2 or 3, who underwent bariatric surgery were allocated to two groups. Patients in group 1 were administered lidocaine (1.5 mg/kg) 5 min before the induction of anesthesia, and group 2 was administered 0.9% saline solution in an equal volume. Subsequently, lidocaine (2 mg/kg/h) or 0.9% saline was infused during the entire surgical procedure. Anesthesia was performed with fentanyl (5 μg/kg), propofol, rocuronium, and sevoflurane. Postoperative patient-controlled analgesia was provided with morphine. The following were evaluated: pain intensity, IL-6, 24-h consumption of morphine, time to the morphine request, time to extubation, and adverse effects.

RESULTS

The lidocaine group had a lower pain intensity than the saline group for up to 1 h, with no differences between groups in IL-6 and time to extubation. The lidocaine group consumed less morphine within 24 h, had a longer time until the first supplemental morphine request, and had a lower incidence of nausea.

CONCLUSIONS

Lidocaine reduced the intensity of early postoperative pain, incidence of nausea, and consumption of morphine within 24 h and increased time to the first morphine request, without reducing the plasma concentrations of IL-6.