Emergency Medicine Case Study on Local Anesthetic Systemic Toxicity.

The purpose of this case study on local anesthetic systemic toxicity (LAST), a potentially life-threatening complication of local anesthetic, is to ensure that emergency nurse practitioners (ENPs) are knowledgeable on this disease process. Local anesthetics are used frequently, often daily, by ENPs, as well as multiple other health care providers for various procedures. They should be knowledgeable of the steps to resuscitate a patient who may have severe LAST. This case study reviews the emergency management of LAST, including pharmacologic treatment, deviations from routine advanced resuscitative guidelines, and disposition of the patient upon successful resuscitation. Additionally, risk assessment and clinical manifestations will be discussed. After reviewing this case study, ENPs should be able to recognize the presentation of LAST and provide emergent management to reduce complications, comorbidities, and death.

Not just tachycardia: A pilot study examining wound­healing complications associated with the dose and volume of lignocaine in skin cancer excisions.

BACKGROUND AND OBJECTIVES: General practitioners excise many suspected skin cancers using local anaesthetics such as lignocaine, but the relationships between the dose and volume of the local anaesthetic and wound complications are unclear. This pilot study considers an association between the dose and volume and complications. METHOD: An audit was conducted of patient records from two time periods: one before and one after an education intervention. Data extracted included lignocaine (volume and dose), wound complications (dehiscence and infection) and the demographics of patients and clinicians. RESULTS: Both the dose and volume of lignocaine administered were significantly associated with complication rates (P=0.0084 and P=0.0209, respectively). In the post-intervention period, clinician behaviour changed, with a reduction in the volume and dose of lignocaine administered (P<0.001 and P<0.001, respectively) without episodes of inadequate analgesia. DISCUSSION: This pilot study reported a relationship between lidocaine dose and volume and rates of complications. Shortcomings of this study limit attribution of findings to clinical practice. However, the results justify further rigorous research.

Reevaluating the epinephrine myth: A comprehensive review.

ABSTRACT: The combination of local anesthetic drugs with epinephrine has conventionally been contraindicated in acral regions due to concerns of potential necrosis caused by compromised blood flow. However, this belief has been challenged since 2001, when studies demonstrated the safety and effectiveness of the combination. This review aims to analyze reported cases of acral area necrosis following the use of local anesthesia with epinephrine since 2001. A thorough search was conducted on PubMed and Google Scholar using specific keywords to identify articles reporting acral area necrosis caused using local anesthesia and epinephrine. Our search yielded eight publications describing a total of 13 cases of ischemic events in acral areas. These cases involved finger necrosis (five cases), scrotal skin necrosis (two cases), and eyelid necrosis (six cases), following the injection of a combination of epinephrine and lignocaine. The majority of affected patients were female who underwent surgical intervention and reconstruction. The use of epinephrine in local anesthesia offers significant advantages and is generally safe for acral areas. However, the risk of necrosis cannot be entirely eliminated, particularly in patients with compromised vascular function. Adhering to proper guidelines and selecting suitable patients can help mitigate the risk. Phentolamine serves as a potential rescue agent if vascular compromise occurs. Precautionary measures must be taken when using this combination in high-risk patients.

EMLA cream in burns: A systematic review of safety, analgesic efficacy, and effects on burn pathophysiology.

AIM: Management of procedural pain in burn care is challenging. Lidocaine-prilocaine cream 5%, eutectic mixture of local anesthetics (EMLA®), is a widely used, effective local anesthetic cream approved for normal intact skin, genital mucosa for superficial surgical procedures, and debridement of chronic leg ulcers. This comprehensive review aimed to determine the safety, analgesic efficacy, and effects of EMLA on burn pathophysiology to provide evidence-based clinical recommendations for introducing the topical anesthetic into burn care. METHODS: The PRISMA guidelines were followed for conducting a systematic PubMed search to include all relevant preclinical and clinical studies, according to pre-specified eligibility criteria. RESULTS: Fifteen studies were included in a qualitative synthesis, among which nine were human and six were animal studies. To date, safety and pharmacokinetic data on EMLA application in burns have been limited. Nevertheless, human studies indicated that EMLA is safe and provides adequate procedural-pain relief in adults when applied to smaller burns. Caution should be exercised when using EMLA in younger children, as systemic toxicity, pertaining to prilocaine-induced methemoglobinemia, has been reported owing to overdosing (high doses applied over large burn areas). Furthermore, animal studies demonstrate the potential beneficial effects of EMLA on burn pathophysiology such as anti-inflammatory, decreased capillary permeability to plasma proteins and edema formation, and improved tissue perfusion, which are factors that may impact burn wound progression. CONCLUSION: Current data on EMLA use in the management of procedural pain in small burns are sparse but suggest that EMLA is safe and effective in adults. Further clinical pharmacokinetic studies are warranted, especially for application on larger burn areas.

Chondrotoxicity of Intra-Articular Injection Treatment: A Scoping Review.

The purpose of this scoping review was to identify possible chondrotoxic effects caused by drugs usually used for intra-articular injections. PubMed, Scopus, Web of Science and Cochrane were searched. Inclusion criteria required randomized controlled trials written in English that evaluate the toxic effect that damages the cartilage. The literature search resulted in 185 unique articles. 133 full-text articles were screened for inclusion, of which 65 were included. Corticosteroids, with the exception of triamcinolone, along with local anaesthetics, potentially excluding ropivacaine and liposomal bupivacaine, and nonsteroidal anti-inflammatory drugs, exhibited insufficient safety profiles to warrant casual use in clinical settings. Hyaluronic acid, on the other hand, appears to demonstrate safety while also mitigating risks associated with concurrent compounds, thereby facilitating therapeutic combinations. Additionally, there remains a paucity of data regarding platelet-rich plasma, necessitating further evaluation of its potential efficacy and safety. Overall, it seems that results are significantly influenced by the dosage and frequency of injections administered, observed in both human and animal studies.

Subdural Spread of Local Anesthetic Mimicking Cerebrovascular Accident: A Case Report of Horner's Syndrome, Upper Limb Paresthesia, and Motor Weakness After Thoracic Epidural Analgesia.

A 53-year-old woman underwent a thoracic epidural placement for a scheduled laparotomy. Postoperatively the patient had no appreciable epidural level after multiple epidural boluses and was noted to be severely hypotensive with right upper extremity weakness and numbness. She subsequently developed right-sided Horner's syndrome with worsening right upper extremity weakness and decreased sensation from C6 to T1. She regained full motor and sensory function in her right upper extremity with epidural removal. This unusual case raises awareness of the variability in the presentation of subdural spread and provides an example of an epidural complication that can mimic a cerebrovascular accident (CVA).

Bupivacaine pleural effusion mimicking a hemothorax after a thoracoscopic microdiscectomy with epidural anesthesia.

PURPOSE: Post-operative pain after video-assisted thoracoscopic surgery is often treated using thoracic epidural analgesics or thoracic paravertebral analgesics. This article describes a case where a thoracic disc herniation is treated with a thoracoscopic microdiscectomy with post-operative thoracic epidural analgesics. The patient developed a bupivacaine pleural effusion which mimicked a hemothorax on computed tomography (CT). METHODS: The presence of bupivacaine in the pleural effusion was confirmed using a high performance liquid chromatography method. RESULTS: The patient underwent a re-exploration to relieve the pleural effusion. The patient showed a long-term recovery similar to what can be expected from an uncomplicated thoracoscopic microdiscectomy. CONCLUSION: A pleural effusion may occur when thoracic epidural analgesics are used in patents with a corridor between the pleural cavity and epidural space.

Occurrence of neurosensory disturbance after the use of articaine and lidocaine in the inferior alveolar nerve block: a double-blind randomised clinical trial.

This double-blind, randomised clinical trial aimed to find out whether there is a difference in the prevalence of neurosensory disturbance (NSD) between patients who received 2% lidocaine and those who received 4% articaine during inferior alveolar nerve blocks (IANBs). Patients who underwent third molar extraction were randomised into two groups. IANB was performed using 2% lidocaine in Group 1 and 4% articaine in Group 2. The occurrence of NSD was documented. Patients were visited within 48 hours and one week after the tooth was removed. The type of anaesthetic drug (4% articaine versus 2% lidocaine) was the study's predictive factor. A total of 2400 patients were studied in two groups (1200 in each group). The mean (range) age of the patients was 28.40 (18-44) years. Five patients (0.41%) in the lidocaine group and seven (0.58%) in the articaine group had NSD after injection (p = 0.77). The prevalence of NSD after IANB was no higher in the articaine group than in the lidocaine group.

A review of local anesthetic-induced heart toxicity using human induced pluripotent stem cell-derived cardiomyocytes.

Local anesthetic (LA) cardiotoxicity is one of the main health problems in anesthesiology and pain management. This study reviewed the reported LA-induced cardiac toxicity types, risk factors, management, and mechanisms, with attention to the use of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in heart toxicity research. Important scientific databases were searched to find relevant articles. We briefly assessed the reported cardiotoxic effects of different types of LA drugs, including ester- and amide-linked LA agents. Furthermore, cardiotoxic effects and clinical manifestations, strategies for preventing and managing LA-induced cardiotoxic effects, pharmacokinetics, pharmacodynamics, and sodium channel dynamics regarding individual variability and genetic influences were discussed in this review. The applications and importance of hiPSC-CMs cellular model for evaluating the cardiotoxic effects of LA drugs were discussed in detail. This review also explored hiPSC-CMs' potential in risk assessment, drug screening, and developing targeted therapies. The main mechanisms underlying LA-induced cardiotoxicity included perturbation in sodium channels, ROS production, and disorders in the immune system response due to the presence of LA drugs. Furthermore, drug-specific characteristics including pharmacokinetics and pharmacodynamics are important determinants after LA drug injection. In addition, individual patient factors such as age, comorbidities, and genetic variability emphasize the need for a personalized approach to mitigate risks and enhance patient safety. The strategies outlined for the prevention and management of LA cardiotoxicity underscore the importance of careful dosing, continuous monitoring, and the immediate availability of resuscitation equipment. This comprehensive review can be used to guide future investigations into better understanding LA cardiac toxicities and improving patient safety.

Prevention of persistent pain with lidocaine infusions in breast cancer surgery (PLAN): study protocol for a multicenter randomized controlled trial.

BACKGROUND: Persistent pain is a common yet debilitating complication after breast cancer surgery. Given the pervasive effects of this pain disorder on the patient and healthcare system, post-mastectomy pain syndrome (PMPS) is becoming a larger population health problem, especially as the prognosis and survivorship of breast cancer increases. Interventions that prevent persistent pain after breast surgery are needed to improve the quality of life of breast cancer survivors. An intraoperative intravenous lidocaine infusion has emerged as a potential intervention to decrease the incidence of PMPS. We aim to determine the definitive effects of this intervention in patients undergoing breast cancer surgery. METHODS: PLAN will be a multicenter, parallel-group, blinded, 1:1 randomized, placebo-controlled trial of 1,602 patients undergoing breast cancer surgery. Adult patients scheduled for a lumpectomy or mastectomy will be randomized to receive an intravenous 2% lidocaine bolus of 1.5 mg/kg with induction of anesthesia, followed by a 2.0 mg/kg/h infusion until the end of surgery, or placebo solution (normal saline) at the same volume. The primary outcome will be the incidence of persistent pain at 3 months. Secondary outcomes include the incidence of pain and opioid consumption at 1 h, 1-3 days, and 12 months after surgery, as well as emotional, physical, and functional parameters, and cost-effectiveness. DISCUSSION: This trial aims to provide definitive evidence on an intervention that could potentially prevent persistent pain after breast cancer surgery. If this trial is successful, lidocaine infusion would be integrated as standard of care in breast cancer management. This inexpensive, widely available, and easily administered intervention has the potential to reduce pain and suffering in an already afflicted patient population, decrease the substantial costs of chronic pain management, potentially decrease opioid use, and improve the quality of life in patients. TRIAL REGISTRATION: This trial has been registered on clinicaltrials.gov (NCT04874038, Dr. James Khan. Date of registration: May 5, 2021).

Regional Anesthesia Complications and Contraindications.

Regional anesthesia has a strong role in minimizing post-operative pain, decreasing narcotic use and PONV, and, therefore, speeding discharge times. However, as with any procedure, regional anesthesia has both benefits and risks. It is important to identify the complications and contraindications related to regional anesthesia, which patient populations are at highest risk, and how to mitigate those risks to the greatest extent possible. Overall, significant complications secondary to regional anesthesia remain low. While a variety of different regional anesthesia techniques exist, complications tend to fall within 4 broad categories: block failure, bleeding/hematoma, neurological injury, and local anesthetic toxicity.

Local Anesthetics, Local Anesthetic Systemic Toxicity (LAST), and Liposomal Bupivacaine.

Local anesthetics have played a vital role in the multimodal analgesia approach to patient care by decreasing the use of perioperative opioids, enhancing patient satisfaction, decreasing the incidence of postoperative nausea and vomiting, decreasing the length of hospital stay, and reducing the risk of chronic postsurgical pain. The opioid-reduced anesthetic management for perioperative analgesia has been largely successful with the use of local anesthetics during procedures such as peripheral nerve blocks and neuraxial analgesia. It is important that practitioners who use local anesthetics are aware of the risk factors, presentation, and management of local anesthetic systemic toxicity (LAST).

Local Anesthetic Systemic Toxicity (LAST): More Common Than You Think.

The number of anesthetic body procedures in the United States is rapidly increasing, with many being performed on an outpatient basis. These procedures are advertised as being safe, and many times the serious complications may not be discussed. Although local anesthetic systemic toxicity is a rare complication, it is associated with an increase in morbidity. The emergency department staff should be aware of the possibility of this rare complication, as well as the variety of resulting symptoms (from minor to severe), potential sequelae, and appropriate management for patients who have undergone an outpatient anesthetic body procedure. Multiple factors contribute to the development of local anesthetic systemic toxicity, resulting in life-threatening effects on the neurologic and cardiovascular systems. Also, the site of administration, along with the local anesthetic agent used, can impact the risk of the development of local anesthetic systemic toxicity. To minimize the risk and ensure the best possible outcome for these patients, emergency department staff must be highly aware of the mechanisms, risk factors, prevention, and management/treatment of local anesthetic systemic toxicity.

AG-920 (Articaine) Ophthalmic Solution: A Masked, Active-Controlled Evaluation of Its Local Anesthetic Efficacy and Safety in Pediatric Patients.

Purpose: The safety and efficacy of a novel topical ocular anesthetic (AG-920 sterile ophthalmic solution, 8%) was previously evaluated in adults. For both clinical and regulatory purposes, this new agent was evaluated in children. Methods: This was a Phase 3, randomized, active-controlled, single-masked, parallel-group design study in healthy pediatric subjects performed at a private practice retina clinic in the United States. The safety and anesthetic efficacy of AG-920 was compared with proparacaine hydrochloride ophthalmic solution 0.5% in 60 children undergoing ophthalmic examinations. The primary efficacy endpoint was whether the investigator was able to perform the eye examination. Results: In all subjects in each treatment group, the investigator was able to perform the eye examination without additional local anesthetic. There were no adverse events reported in this study. In both the study eye and fellow eye, there were no notable changes after dosing, and both treatment groups were similar. All external eye exams in all subjects in both treatment groups were normal. Conclusions: In this pediatric population aged 7 months to >11 years, AG-920 was therapeutically equivalent to marketed proparacaine with respect to having an ophthalmic examination performed without needing additional local anesthetic. Further, AG-920 was well tolerated, and there were no clinically significant safety findings.

Using part of the initial analgesic dose as the epidural test dose did not delay the onset of labor analgesia: a randomized controlled clinical trial.

BACKGROUND: Epidural test dose for labor analgesia is controversial and varies widely in clinical practice. It is currently unclear whether using a portion of the initial dose for analgesia as the test dose delays the onset time of analgesia, compared to the traditional test dose. METHODS: One hundred and twenty-six parturients who chose epidural analgesia during labor were randomly assigned to two groups. The first dose in group L was 3 ml 1.5% lidocaine, and in the RF group was 10 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. After 3 min of observation, both groups received 8 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. The onset time of analgesia, motor and sensory blockade level, numerical pain rating scale, patient satisfaction score, and side effects were recorded. RESULTS: The onset time of analgesia in group RF was similar to that in group L (group RF vs group L, 7.0 [5.0-9.0] minutes vs 8.0 [5.0-11.0] minutes, p = 0.197). The incidence of foot numbness (group RF vs group L, 34.9% vs 57.1%, p = 0.020) and foot warming (group RF vs group L, 15.9% vs 47.6%, p < 0.001) in group RF was significantly lower than that in group L. There was no difference between the two groups on other outcomes. CONCLUSIONS: Compared with 1.5% lidocaine 3 ml, 0.1% ropivacaine 10 ml combined with 2 µg/ml fentanyl as an epidural test dose did not delay the onset of labor analgesia, and the side effects were slightly reduced. CLINICAL TRIAL REGISTRATION: http://www.chictr.org.cn (ChiCTR2100043071).