Safety and Efficacy of Intravenous Lidocaine for Pain Management in the Emergency Department: A Systematic Review

Magnesium Sulfate Versus Lidocaine as an Adjunct for Renal Colic in the Emergency Department: A Randomized, Double-Blind Controlled Trial

STUDY OBJECTIVE

We wished to determine whether the addition of magnesium sulfate (MgSO4) or lidocaine to diclofenac could improve the analgesic efficacy in emergency department (ED) patients with acute renal colic.

METHODS

In this prospective, double-blinded, randomized controlled trial of patients aged 18 to 65 years with suspected acute renal colic, we randomized them to receive 75 mg intramuscular (IM) diclofenac and then intravenous (IV) MgSO4, lidocaine, or saline solution control. Subjects reported their pain using a numerical rating scale (NRS) before drug administration and then 5, 10, 20, 30, 60, and 90 minutes afterwards. Our primary outcome was the proportion of participants achieving at least a 50% reduction in the NRS score 30 minutes after drug administration.

RESULTS

We enrolled 280 patients in each group. A 50% or greater reduction in the NRS score at 30 minutes occurred in 227 (81.7%) patients in the MgSO4 group, 204 (72.9%) in the lidocaine group, and 201 (71.8%) in the control group, with significant differences between MgSO4 and lidocaine (8.8%, 95% confidence interval [CI] [1.89 to 15.7], P=.013) and between MgSO4 and control (9.9%, 95% CI [2.95 to 16.84], P=.004). Despite this, differences between all groups at every time point were below the accepted 1.3 threshold for clinical importance. There were no observed differences between groups in the frequency of rescue analgesics and return visits to the ED for renal colic. There were more adverse events, although minor, in the MgSO4 group.

CONCLUSION

Adding intravenous MgSO4, but not lidocaine, to IM diclofenac offered superior pain relief but at levels below accepted thresholds for clinical importance.

Wilderness Medical Society Clinical Practice Guidelines for the Treatment of Acute Pain in Austere Environments: 2024 Update

The Wilderness Medical Society (WMS) convened an expert panel to develop evidence-based guidelines for the management of pain in austere environments. Recommendations are graded based on the quality of supporting evidence as defined by criteria put forth by the American College of Chest Physicians. This is an update of the 2014 version of the "WMS Practice Guidelines for the Treatment of Acute Pain in Remote Environments" published in Wilderness & Environmental Medicine 2014; 25:41-49.

The Use of Intravenous Lidocaine as an Analgesic Modality in the Austere Environment: Two Cases

Providing effective analgesia for trauma in austere settings is particularly difficult and often complicated by equipment and medication limitations and harsh environmental conditions. Common modalities that are employed in conventional clinical practices may not be available or pragmatic in austere environments. Furthermore, side effects such as sedation, altered mentation, or hypoxemia require additional resources and attention. We report 2 cases that demonstrate the use of intravenous lidocaine for the management of acute pain, secondary to trauma, in an austere environment. In the first, the administration of intravenous lidocaine reduced pain, secondary to a tibia fracture, thereby facilitating splinting. In the second, a patient, who had sustained rib fractures, was also treated with intravenous lidocaine. In this case, the analgesic effects of the medication resulted in reduction in pain and improvement in pulmonary function. Of note, the narrow therapeutic window of this modality was made evident as both patients transiently experienced tinnitus following the initial lidocaine bolus. This report describes 2 cases in which intravenous lidocaine was used to manage acute pain, in an austere environment, while avoiding many of the detrimental effects that accompany alternative analgesics.

The Use of Intravenous Lidocaine in Perioperative Medicine: Anaesthetic, Analgesic and Immune-Modulatory Aspects

This narrative review provides an update on the applied pharmacology of lidocaine, its clinical scope in anaesthesia, novel concepts of analgesic and immune-modulatory effects as well as the current controversy around its use in perioperative opioid-sparing multi-modal strategies. Potential benefits of intravenous lidocaine in the context of cancer, inflammation and chronic pain are discussed against concerns of safety, toxicity and medico-legal constraints.

Analgesic Treatment and the Patients' Opinion on the Hospital Emergency Department

Aim: The aim of the study was to analyze whether a patient’s opinion is related to the effect of analgesic treatment. Methods: The study was conducted using a survey questionnaire among adult patients admitted to the hospital emergency department in March 2021. The Numerical Rating Scale (NRS) was used to assess pain. Patients were asked to rate the intensity of pain during their stay in the emergency department in three situations: (1) at admission; (2) during the stay; and (3) upon discharge. The relationships between qualitative variables were assessed by the chi-squared test. Significance was set at p < 0.05. Results: There was no statistical dependence between the patient’s opinion about the medical institution and results of the effectiveness of analgesic treatments (p = 0.056). The highest percentage of patients satisfied with the received treatment were those who did not feel pain during ED discharge (94.12%), and the lowest were those who complained of severe pain during ED discharge (63.91%). The average mark for the functioning and organization of the emergency department was 7.44 (±2.04). Only 54 patients (29.83%) had taken pain medication before deciding to visit ED. Conclusions: No statistical dependency between the effect of the analgesic treatment and the patient’s opinion has been observed. The majority of patients with pain discomfort visit emergency departments without looking for consultation in other locations or without taking analgesics. In the considered institution, patients were satisfied with the analgesic treatment, staff performance, and with the organization of the department.

The canine chronic atrioventricular block model in cardiovascular preclinical drug research

Ventricular cardiac arrhythmia is a life threating condition arising from abnormal functioning of many factors in concert. Animal models mirroring human electrophysiology are essential to predict and understand the rare pro- and anti-arrhythmic effects of drugs. This is very well accomplished by the canine chronic atrioventricular block (CAVB) model. Here we summarize canine models for cardiovascular research, and describe the development of the CAVB model from its beginning. Understanding of the structural, contractile and electrical remodelling processes following atrioventricular (AV) block provides insight in the many factors contributing to drug-induced arrhythmia. We also review all safety pharmacology studies, efficacy and mechanistic studies on anti-arrhythmic drugs in CAVB dogs. Finally, we compare pros and cons with other in vivo preclinical animal models. In view of the tremendous amount of data obtained over the last 100 years from the CAVB dog model, it can be considered as man's best friend in preclinical drug research. LINKED ARTICLES: This article is part of a themed issue on Preclinical Models for Cardiovascular disease research (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.5/issuetoc.

Comparison of the Efficacy of Nonsteroidal Anti-Inflammatory Drugs and Opioids in the Treatment of Acute Renal Colic: A Systematic Review and Meta-Analysis

Background: Although multiple randomized controlled trials (RCTs) and systematic review and meta-analysis were performed to investigate the efficiency and safety of nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids in the treatment of acute renal colic, the therapeutic regimen of renal colic is still controversial. Therefore, the aim of this study was to derive a more concise comparison of the effectiveness and safety between NSAIDs and opioids in the treatment for patients with acute renal colic by a systematic review and meta-analysis.

Design: We searched PubMed, Embase, and Cochrane Central Register of controlled trials for seeking eligible studies. The pooled mean difference (MD) or risk ratio (RR) with 95% confidence interval (CI) was calculated using the random effects model. The primary outcome was assessed according to the Grading of Recommendations Assessment, Development and Evaluation.

Results: A total of 18 studies involving 3,121 participants were included in the systematic review and meta-analysis. No significant difference between the NSAID and opioid groups was observed, with changes in the visual analog scale (VAS) at 0–30 min (MD = 0.79, 95% CI: −0.51, 2.10). NSAIDs in the form of intravenous administration (IV) had no better effect on the changes in the VAS at 0–30 min, when compared to opioids (MD = 1.25, 95% Cl: −4.81, 7.3). The NSAIDs group in the form of IV had no better outcome compared to the opioids group, as well as the VAS at 30 min (MD = −1.18, 95% Cl: −3.82, 1.45; MD = −2.3, 95% Cl: −5.02, 0.42, respectively). Moreover, similar results of this outcome were also seen with the VAS at 45 min (MD = −1.36, 95% Cl: −5.24, 2.52). Besides, there was a statistical difference in the incidence of later rescue (RR = 0.76, 95% CI: 0.66, 0.89), drug-related adverse events (RR = 0.44, 95% CI: 0.27, 0.71), and vomiting (RR = 0.68, 95% CI: 0.49, 0.96).

Conclusion: There is no significant difference between the NSAIDs and opioids in the treatment of renal colic in many outcomes (e.g., the VAS over different periods using different injection methods at 30 and 60 min), which has been focused on in this study. However, the patients who were treated using NSAIDs by clinicians can benefit from fewer side effects.

Studies on local anesthetic lidocaine hydrochloride delivery via photo-triggered implantable polymeric microneedles as a patient-controlled transdermal analgesia system

This study aimed to develop photo-triggered implantable polymeric microneedles (MNs) for successful drug delivery in a transdermal analgesia system. The prepared iron oxide nanoparticles (Fe₃O₄NPs) were coated with polydopamine (PDA) followed by polyvinylpyrrolidone (PVP) and polycaprolactone (PCL). While the PCL/PVP-Fe₃O₄NPs synthesis, the absorption band of PVP at 1656 cm^-1 shifted to 1665 cm^-1 which indicate the presence of interaction between Fe⁺ and C = O groups. The size and morphology of PCL/PVP-Fe₃O₄NPs were examined by scanning electron microscope and transmission electron microscope (SEM and TEM) analysis. The results confirmed that the prepared PCL/PVP-Fe₃O₄NPs were spherical with sizes ranging from 9 to 11 nm. The lidocaine hydrochloride content in the microneedles was 3.72 ± 0.31 mg and A + 2.2S ≤ L representing that the drug was uniformly distributed. The insertion ability of lidocaine hydrochloride@PCL/PVP-Fe₃O₄NPs-DMNs was tested by porcine skin. The results demonstrated outstanding insertion ability and potential for drug delivery. In addition, near-infrared (NIR) irradiation has the potential to penetrate the skin and enhance lidocaine hydrochloride-releasing activity. The in vivo experimental data confirmed that lidocaine hydrochloride@PCL/PVP-Fe₃O₄NPs-DMNs allowed for painless drug delivery by breaking the barrier of the stratum corneum. To conclude, lidocaine hydrochloride can be safely delivered through the transdermal analgesic system, with a quick onset time.

Efficacy of Intravenous Lidocaine for Pain Relief in the Emergency Department: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare the efficacy of intravenous (IV) lidocaine with standard analgesics (NSAIDS, opioids) for pain control due to any cause in the emergency department.

METHODS

The electronic databases of PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar were explored from 1st January 2000 to 30th March 2021 and randomized controlled trials (RCTs) comparing IV lidocaine with a control group of standard analgesics were included.

RESULTS

Twelve RCTs including 1,351 patients were included. The cause of pain included abdominal pain, renal or biliary colic, traumatic pain, radicular low back pain, critical limb ischemia, migraine, tension-type headache, and pain of unknown origin. On pooled analysis, we found no statistically significant difference in pain scores between IV lidocaine and control group at 15 min (MD: -0.24 95% CI: -1.08, 0.61 I 2 = 81% p = 0.59), 30 min (MD: -0.24 95% CI: -1.03, 0.55 I 2 = 86% p = 0.55), 45 min (MD: 0.31 95% CI: -0.66, 1.29 I 2 = 66% p = 0.53), and 60 min (MD: 0.59 95% CI: -0.26, 1.44 I 2 = 75% p = 0.18). There was no statistically significant difference in the need for rescue analgesics between the two groups (OR: 1.45 95% CI: 0.82, 2.56 I 2 = 41% p = 0.20), but on subgroup analysis, the need for rescue analgesics was significantly higher with IV lidocaine in studies on abdominal pain but not for musculoskeletal pain. On meta-analysis, there was no statistically significant difference in the incidence of side-effects between the two study groups (OR: 1.09 95% CI: 0.59, 2.02 I 2 = 48% p = 0.78).

CONCLUSION

IV lidocaine can be considered as an alternative analgesic for pain control in the ED. However, its efficacy may not be higher than standard analgesics. Further RCTs with a large sample size are needed to corroborate the current conclusions.

Pain management in the emergency department: a clinical review

Pain is one of the most common reasons for patients to visit the emergency department. The ever-growing research on emergency department analgesia has challenged the current practices with respect to the optimal analgesic regimen for acute musculoskeletal pain, safe and judicious opioid prescribing, appropriate utilization of non-opioid therapeutics, and non-pharmacological treatment modalities. This clinical review is set to provide evidence-based answers to these challenging questions.

Less Exposure for Health Care Workers, More Comfort for Patients During COVID-19 Swab Testing

BACKGROUND

Nasopharyngeal (NP) and oropharyngeal (OP) swab sampling for coronavirus disease 2019 (COVID-19) diagnosis may lead to droplet and/or airborne particle transmission and increase the exposure risk for health care workers (HCWs). However, there is limited evidence for effective methods to reduce occupational exposure from NP and OP swab sampling. This study aimed to reduce droplet-forming responses (DFRs) and the related exposure risk of NP and OP swab sampling by administering 10% lidocaine spray (LS) to the NP and OP areas prior to conducting swab tests.

METHODS

This quasi-experimental study was conducted with 100 patients who presented to our tertiary care hospital with symptoms of COVID-19 between December 1 and 15, 2020. First, NP and OP swabbings were performed on each patient. Thereafter, LS was applied to the OP and NP regions, and the swab samples were taken once again. Frequency of DFRs and real-time polymerase chain reaction (RT-PCR) test results before and after LS application were recorded for comparison. In addition, the cycle threshold (Ct) was used as a proxy indicator for SARS-CoV-2 viral load in COVID-19 positive cases.

FINDINGS

Significant differences in OP DFR frequencies before and after LS intervention were found (37% and 9%, respectively), as well as before and after NP DFR (31% and 18%, respectively). The mean Ct values for the positive samples did not differ before and after applying LS.

CONCLUSION

Our results suggest that applying LS to the OP and NP area prior to swab testing reduces DFR frequencies without affecting (RT-PCR) test results for SARS-CoV-2 and may increase patient and practitioner comfort.

Key articles and guidelines for the emergency medicine clinical pharmacist: 2011-2018 update

PURPOSE

To summarize recently published research reports and practice guidelines on emergency medicine (EM)-related pharmacotherapy.

SUMMARY

Our author group was composed of 14 EM pharmacists, who used a systematic process to determine main sections and topics for the update as well as pertinent literature for inclusion. Main sections and topics were determined using a modified Delphi method, author and peer reviewer groups were formed, and articles were selected based on a comprehensive literature review and several criteria for each author-reviewer pair. These criteria included the document "Oxford Centre for Evidence-based Medicine - Levels of Evidence (March 2009)" but also clinical implications, interest to reader, and belief that a publication was a "key article" for the practicing EM pharmacist. A total of 105 articles published from January 2011 through July 2018 were objectively selected for inclusion in this review. This was not intended as a complete representation of all available pertinent literature. The reviewed publications address the management of a wide variety of disease states and topic areas that are commonly found in the emergency department: analgesia and sedation, anticoagulation, cardiovascular emergencies, emergency preparedness, endocrine emergencies, infectious diseases, neurology, pharmacy services and patient safety, respiratory care, shock, substance abuse, toxicology, and trauma.

CONCLUSION

There are many important recent additions to the EM-related pharmacotherapy literature. As is evident with the surge of new studies, guidelines, and reviews in recent years, it is vital for the EM pharmacist to continue to stay current with advancing practice changes.

Pre-procedure intravenous lidocaine administration on propofol consumption for endoscopic retrograde cholangiopancreatography: A prospective, randomized, double-blind study

BACKGROUND AND AIM

The endoscopic retrograde cholangiopancreatography (ERCP) procedure is generally performed in patients with high comorbidity. We aimed to reduce the consumption of propofol by adding lidocaine before ERCP.

METHODS

Eighty ERCP patients with ASA I-III, aged between 45-75 years, were randomly divided into two groups. Lidocaine group (group L, n = 40), received 1-mg midazolam, 1.5 mg/kg lidocaine, and 1 mg/kg propofol intravenously. The control group (group C, n = 40) received 1-mg midazolam, saline in the same volume as the lidocaine group, and 1 mg/kg propofol intravenously. Propofol was administered with intermittent bolus doses. Propofol consumption, oropharyngeal reflex, recovery time, endoscopist satisfaction, ketamine need, and side-effects were recorded.

RESULTS

Propofol consumption during the procedure was statistically lower in group L than in the control group (157.25 ± 39.16 mg vs 228.75 ± 64.62 mg respectively, P < 0.001). Additionally, recovery time was statistically faster in group L compared with the control group (7.78 ± 3.95 min vs 11.92 ± 3.24 min respectively, P < 0.001). The oropharyngeal reflex was less in group L than control group (6/40 vs 15/40 respectively, P = 0.042). There was no significant difference between the two groups regarding visual analogue scale scores and endoscopist satisfaction (P > 0.05).

CONCLUSIONS

We recommend the use of intravenous lidocaine before the ERCP procedure as it reduces propofol consumption, recovery times, and oropharyngeal reflex.

Does Inhaled Methoxyflurane Implement Fast and Efficient Pain Management in Trauma Patients? A Systematic Review and Meta-Analysis

Introduction

Evidence on the use of inhaled methoxyflurane in the management of trauma pain is conflicting and obfuscated. This study aimed to determine the efficacy and safety of inhaled methoxyflurane for trauma pain on the basis of published randomized controlled trials (RCTs).

Methods

RCTs assessing the efficacy of methoxyflurane in adults or adolescents with acute trauma pain published in PubMed, Web of Science, Embase, Cochrane Library, and Google Scholar were searched. The control groups were those that received placebo or standard analgesic treatment (SAT). The primary outcome was the change from baseline in pain scores during the first 30 min of treatment. Secondary outcomes included time to first pain relief, the proportion of patients experiencing pain relief, rescue analgesia rate, the treatment satisfaction of patients and investigators, and the methoxyflurane-related treatment-emergent adverse events (TEAEs).

Results

A total of nine RCTs (1806 patients) were identified. Results revealed that methoxyflurane provided a clinically unimportant benefit by improving the mean difference of change from baseline in pain intensity (from − 0.44 to − 1.23 cm, p < 0.001) at various time points within the first 20 min compared to control treatment. Besides, methoxyflurane decreased the time of onset of pain relief (mean difference − 5.29 min; 95% CI − 6.97 to − 3.62) and the proportion of patients who needed rescue analgesic medication (risk ratio 1.41; 95% CI 1.17–1.70) despite it increasing the risk of non-severe TEAEs (risk ratio 3.09; 95% CI 1.72–5.57). Notably, the benefit of almost all secondary pain-related outcomes was rendered clinically nonsignificant between methoxyflurane and SAT strata besides the time of onset of pain relief. The quality of evidence was low or very low in all outcomes.

Conclusions

In emergency situations without effective therapy, this systematic review and meta-analysis provides low-quality evidence that methoxyflurane can be used as a rapid-acting and effective treatment for acute trauma pain, although its utilization is associated a risk of non-severe TEAEs. However, the current evidence does not support the notion that inhaled methoxyflurane offered superior analgesic efficacy to SAT.

Clinical Trial Number

PROSPERO registration number CRD42020223000.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40122-021-00258-9.

Updates in our understanding of local anaesthetic systemic toxicity: a narrative review

Despite advances in clinical practice, local anaesthetic systemic toxicity continues to occur with the therapeutic use of local anaesthesia. Patterns of presentation have evolved over recent years due in part to the increasing use of ultrasound which has been demonstrated to reduce risk. Onset of toxicity is increasingly delayed, a greater proportion of clinical reports are secondary to fascial plane blocks, and cases are increasing where non-anaesthetist providers are involved. The evolving clinical context presents a challenge for diagnosis and requires education of all physicians, nurses and allied health professionals about these changing patterns and risks. This review discusses: mechanisms; prevention; diagnosis; and treatment of local anaesthetic systemic toxicity. The local anaesthetic and dose used, site of injection and block conduct and technique are all important determinants of local anaesthetic systemic toxicity, as are various patient factors. Risk mitigation is discussed including the care of at-risk groups, such as: those at the extremes of age; patients with cardiac, hepatic and specific metabolic diseases; and those who are pregnant. Advances in the changing clinical landscape with novel applications and settings for the use of local anaesthesia are also described. Finally, we signpost future directions to potentially improve the management of local anaesthetic systemic toxicity. The utility of local anaesthetics remains unquestionable in clinical practice, and thus maximising the safe and appropriate use of these drugs should translate to improvements in patient care.

Educating Nurses on Intravenous Lidocaine for Postoperative Pain Management

As healthcare practitioners continue to search for multimodal analgesic therapies to reduce postoperative opioid requirements, surgical ward nurses need to stay up to date on the status of emerging therapies. One of these is intravenous lidocaine for postoperative pain management. Unfortunately, there is a lack of resources to assist surgical ward nurses who are unfamiliar with lidocaine infusions for pain. This article aims to review the pharmacology of intravenous lidocaine for pain management, describe an experience of a university-affiliated Veterans Affairs hospital with implementation of intravenous lidocaine on the surgical ward, and suggest practical tools that can be used to develop protocols and educational content for nurses managing intravenous lidocaine infusions in the postoperative period.

Perioperative Intravenous Lidocaine Infusion Adverse Reaction: A Case Report

Intravenous lidocaine is increasingly being utilized as an opioid-sparing analgesic. A 55-year-old man with well-controlled human immunodeficiency virus on highly active antiretroviral therapy was prescribed a lidocaine infusion at 1 mg/kg/h for postoperative pain. On postoperative day 2, the patient experienced 4 unresponsive episodes with tachycardia, hypertension, and oxygen desaturation. Serum lidocaine level was available 2 days later (high 6.3 µg/mL, therapeutic range 2.5-3.5 µg/mL). There is significant pharmacokinetic interaction between lidocaine and this patient's human immunodeficiency virus medications. This case highlights the need for a readily accessible list of medications that caution against lidocaine. We propose in-house serum lidocaine levels to monitor patients at an increased risk for toxicity.

Global Emergency Medicine: A Review of the Literature from 2018

OBJECTIVES

The Global Emergency Medicine Literature Review (GEMLR) conducts a systematic annual search of peer-reviewed and gray literature relevant to global emergency medicine (EM) to identify, review, and disseminate the most rigorously conducted and widely relevant research in global EM.

METHODS

An electronic search of PubMed, a comprehensive retrieval of articles from specific journals, and search of the gray literature were conducted. Title and abstracts retrieved by these searches were screened by a total of 22 reviewers based on their relevance to the field of global EM, across the domains of disaster and humanitarian response (DHR), emergency care in resource-limited settings (ECRLS), and emergency medicine development (EMD). All articles that were deemed relevant by at least one reviewer, their editor, and the managing editor underwent formal scoring of overall methodologic quality and importance to global EM. Two independent reviewers scored all articles; editors provided a third score in cases of widely discrepant scores.

RESULTS

A total of 19,102 articles were identified by the searches and, after screening and removal of duplicates, a total of 517 articles underwent full review. Twenty-five percent were categorized as DHR, 61% as ECRLS, and 15% as EMD. Inter-rater reliability testing between the reviewers revealed a Cohen's kappa score of 0.213 when considering the complete score or 0.426 when excluding the more subjective half of the score. A total of 25 articles scored higher than 17.5 of 20; these were selected for a full summary and critique.

CONCLUSIONS

In 2018, the total number of articles relevant to global EM that were identified by our search continued to increase. Studies and reviews focusing on pediatric infections, several new and traditionally underrepresented topics, and landscape reviews that may help guide clinical care in new settings represented the majority of top-scoring articles. A shortage of articles related to the development of EM as a specialty was identified.

Beyond Opioids for Pain Management in Adult Critically Ill Patients

Critically ill patients commonly experience pain, and the provision of analgesia is an essential component of intensive care unit (ICU) care. Opioids are the mainstay of pain management in the ICU but are limited by their adverse effects, risk of addiction and abuse, and recent drug shortages of injectable formulations. A multimodal analgesia approach, utilizing nonopioid analgesics as adjuncts to opioid therapy, is recommended since they may modulate the pain response and reduce opioid requirements by acting on multiple pain mediators. Nonopioid analgesics discussed in detail in this article are acetaminophen, α-2 receptor agonists, gabapentinoids, ketamine, lidocaine, and nonsteroidal anti-inflammatory drugs. This literature review describes the clinical pharmacology, supportive ICU and relevant non-ICU data, and practical considerations associated with the administration of nonopioid analgesics in critically ill adult patients.

Randomized Trial of Intravenous Lidocaine Versus Hydromorphone for Acute Abdominal Pain in the Emergency Department

STUDY OBJECTIVE

We compare the efficacy and safety of intravenous lidocaine with that of hydromorphone for the treatment of acute abdominal pain in the emergency department (ED).

METHODS

This was a randomized, double-blind, clinical trial conducted in 2 EDs in the Bronx, NY. Adults weighing 60 to 120 kg were randomized to receive 120 mg of intravenous lidocaine or 1 mg of intravenous hydromorphone. Thirty minutes after administration of the first dose of the study drug, participants were asked whether they needed a second dose of the investigational medication to which they were randomized. Patients were also stratified according to clinical suspicion of nephrolithiasis. The primary outcome was improvement in pain scores of 0 to 10 between baseline and 90 minutes. An important secondary outcome was need for "off-protocol" parenteral analgesics, including opioids and nonsteroidal anti-inflammatory drugs.

RESULTS

We enrolled 154 patients, of whom 77 received lidocaine and 77 received hydromorphone. By 90 minutes, patients randomized to lidocaine improved by a mean of 3.8 points on the 0-to-10 scale, whereas those randomized to hydromorphone improved by a mean of 5.0 points (mean difference 1.2; 95% confidence interval 0.3 to 2.2). Need for off-protocol "rescue" analgesics occurred for 39 of 77 lidocaine patients (51%) and 20 of 77 hydromorphone patients (26%) (difference 25%; 95% confidence interval 10% to 40%). Adverse events were comparable between groups. Among the subset of 22 patients with nephrolithiasis, lidocaine patients reported a mean improvement of 3.4 points on the pain scale, whereas hydromorphone patients reported a mean improvement of 6.4 points (mean difference 3.0; 95% confidence interval 0.5 to 5.5).

CONCLUSION

Intravenous hydromorphone was superior to intravenous lidocaine both for general abdominal pain and a subset of patients with nephrolithiasis. A majority of patients randomly allocated to lidocaine required additional analgesics.

Comparison of intravenous lidocaine/ketorolac combination to either analgesic alone for suspected renal colic pain in the ED

STUDY OBJECTIVE

To compare analgesic efficacy and safety of intravenous lidocaine and ketorolac combination to each analgesic alone for ED patients with suspected renal colic.

METHODS

We conducted a randomized, double-blind trial comparing analgesic efficacy of a combination of intravenous lidocaine (1.5 mg/kg) and ketorolac (30 mg), to ketorolac (30 mg), and to lidocaine (1.5 mg/kg) in patients aged 18-64 presenting to the ED with suspected renal colic. Primary outcome included difference in pain scores between the groups at 30 min. Secondary outcomes included a comparative reduction in pain scores in each group from baseline to 30 and 60 min as well as rates of adverse events and need for rescue analgesia at 30 and 60 min.

RESULTS

We enrolled 150 subjects (50 per group). The difference in mean pain scores at 30 min between Lidocaine and Lidocaine/Ketorolac groups was -2.89 (95% CI: -4.39 to -1.39); between Ketorolac and Lidocaine/Ketorolac group was -0.92 (95% CI: -2.44 to 0.61); and between Ketorolac and Lidocaine was -1.98 (95% CI: -3.69 to -0.27). A comparative percentage of subjects in each group required rescue analgesia at 30 and 60 min. No clinically concerning changes in vital signs were observed. No serious adverse events occurred in either group. Commonly reported adverse effects were dizziness, nausea, and headache.

CONCLUSION

The administration of intravenous lidocaine/ketorolac combination to ED patients with suspected renal colic results in better analgesia in comparison to lidocaine alone but provides no analgesic advantages over ketorolac alone. Clinicaltrials.gov Registration: NCT02902770.