Local Anesthetic Systemic Toxicity Research Articles

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.

Local Anesthetic Systemic Toxicity (LAST) and Fascia Iliaca Compartment Block (FICB) Simulation: A Pilot Study

Local Anesthetic Systemic Toxicity (LAST) and Fascia Iliaca Compartment Block (FICB) Simulation: A Pilot Study

Development and validation of an assessment tool for adult simulated ultrasound-guided fascia iliaca block: a prospective monocentric study

BackgroundFascia iliaca block (FIB) is an effective technique for analgesia. While FIB using ultrasound is preferred, there is no current standardised training technique or assessment scale. We aimed to create...

A comparative study between 0.5% Ropivacaine with clonidine versus 0.5% Ropivacaine with dexmedetomidine in ultra sound guided supraclavicular brachial plexus block

Adjuvants in blockade of the brachial plexus can lengthen patient care and hasten the ambulation with stable hemodynamics. Brachial plexus block has possible complications like local anaesthetic systemic toxicity, pneumothorax, nerve injury etc. which can be overcome by use of ultrasound guidance with adjuvants like dexmedetomidine and clonidine for postoperative analgesia. Ropivacaine has higher motor to sensory differentiation and lesser cardiotoxicity.A prospective blinded study comprising of 90 subjects posted for elective upper extremity surgeries. To compare the onset, duration of sensory and motor blockade and analgesia of 0.5% ropivacaine with clonidine 1mg.kg- and 0.5% ropivacaine with dexmedetomidine 1mg.kg-. Ninety patients aged 18 – 60yrs were chosen and randomly allocated into two groups of 45 participants. 20mL of 0.5% Ropivacaine and dexmedetomidine 1mg.kg-was administered to Group A and Group B received Ropivacaine and clonidine 1mg.kg-. In Group A, 73.3% of the subjects showed onset of sensory block of 8 minutes while it was 10 minutes in 26.7% of the subjects. In Group B, 44.4% of the patients showed onset of sensory block of 8 minutes, and 26.7% of the patients showed onset of sensory block of 10 min. Statistically, subjects in Group A showed decrease in onset of block and a higher mean duration of sensory and motor block in contrast to Group B. Addition of dexmedetomidine to 0.5% ropivacaine in supraclavicular brachial plexus block decreased the time of onset of sensory and motor block and extended the period of analgesia.

Dose safety and pharmacodynamics of subcutaneous bupivacaine in a novel extended-release microparticle formulation: A phase 1, dose-ascending study in male volunteers.

A novel microparticle-based extended-release local anaesthetic containing a bupivacaine/poly-lactic-co-glycolic acid (PLGA; LIQ865A) or plain bupivacaine (LIQ865B) was examined in a first-in-human trial. The objectives were to examine the dose safety/tolerability and pharmacodynamics. Randomized subcutaneous injections of LIQ865A (n = 16) or LIQ865B (n = 12) and diluent, contralaterally, were administered in a dose-ascending manner (150- to 600-mg bupivacaine). Subjects were admitted 24 h post-injection and followed for 30 days post-injection. The risk ratios (RRs; 95% CI) of erythematous reactions for LIQ865A versus diluent was 9.00 (1.81-52.23; P = 0.006) and for LIQ865B versus diluent 2.50 (0.69-9.94; P = 0.37). The RR for the development of hematomas (LIQ865A versus diluent) were 3.25 (1.52-8.16; P = 0.004) and 4.00 (0.72-24.89; P = 0.32) (LIQ865B versus diluent). Subcutaneous indurations persisting for 4-13 weeks were seen in 6/16 subjects receiving LIQ865A. One subject receiving LIQ865A (600-mg bupivacaine) developed intermittent central nervous system (CNS) symptoms of local anaesthetic systemic toxicity (85 min to 51 h post-injection) coinciding with plasma peak bupivacaine concentrations (490-533 ng/ml). Both LIQ865 formulations demonstrated dose-dependent hypoesthesia and hypoalgesia. The duration of analgesia ranged between 37 and 86 h. The overall number of local adverse events, however, prohibits clinical application without further pharmacological modifications.

Use IV Lipid Emulsion for Local Anesthetic System Toxicity

Use IV Lipid Emulsion for Local Anesthetic System Toxicity

Preventing Local Anesthetic Systemic Toxicity After Administration of Long-Acting Local Anesthetics.

Preventing Local Anesthetic Systemic Toxicity After Administration of Long-Acting Local Anesthetics.

Inhibition of the glutamatergic PVT-NAc projections attenuates local anesthetic-induced neurotoxic behaviors

IntroductionLocal anesthetic-induced neurotoxicity contributes to perioperative nerve damage; however, the underlying mechanisms remain unclear. Here, we investigated the role of the paraventricular thalamus (PVT)-nucleus accumbens (NAc) projections in neurotoxicity induced...

Systematic Review of Local Anaesthetic Systemic Toxicity in Urology.

To systematically evaluate cases of local anaesthetic systemic toxicity (LAST) in adult urological patients. A search of the Cochrane, Embase, and Medline databases as well as grey literature from 1 January 1974 to 1 February 2023 was performed using reported methods. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Eligible studies were published in English, described LAST secondary to local anaesthetic administration by urological medical staff to an adult patient, and reported >1 symptom of LAST. One hundred fifty-seven publications were screened, and six eligible studies (all case reports) were identified, representing six cases of LAST in adult urological patients. Patients were aged 29-54 years and one was female. Cases occurred secondary to penile dorsal nerve block (two cases), scrotal self-injection (two), circumcision (one) or trans-vaginal tape insertion (one). Causative drugs were lidocaine (three patients; median dose 600mg) and bupivacaine (three; 200mg). While one patient was found deceased at home and received no treatment, five experienced LAST as inpatients and were discharged with no deficit. Three patients (50%) experienced a state of reduced consciousness or seizures, one experienced psychosis and one had asymptomatic tachyarrhythmia. Management consisted of supportive management (five patients), intravenous lipid emulsion (three) or intravenous thiopental and diazepam (one). Recommended tools suggested that two of these studies were at moderate or high risk of bias. LAST is seen only rarely in adult urology. Most iatrogenic cases occur due to penile dorsal nerve block and most patients have no long-term sequelae. Urologists should be familiar with its presentation and management, and minimise risk by adhering to local anaesthetic maximum safe dose ranges.

Local anesthetic systemic toxicity: An effort to identify knowledge gaps across specialties.

Physical medicine and rehabilitation (PM&R) physicians are trained to perform interventional procedures using local anesthetics (LAs) to reduce pain and enhance function and quality of life. LA administration is not benign and one potential complication is local anesthetic systemic toxicity (LAST). Anesthesiologists also perform interventions with LAs; however, training on LAST may differ between medical specialties. To investigate if a gap exists in the knowledge of LAST between physiatry and anesthesiology physicians. Prospective cross-sectional survey study. All residents, fellows, and attendings of the anesthesiology and PM&R departments at a single academic medical center. The primary outcome measures include participants' self-reported exposure to LAST education and comfort with their LAST knowledge as recorded on a Likert scale, as well as the percentage of correctly answered knowledge-based questions on the topic. Fifty-eight physicians including 28 PM&R and 30 anesthesiology physicians (24 attending and 34 trainees) participated. Anesthesiology trainees and attendings exhibited greater overall perceived knowledge of LAST (trainees U = 43, p < .001; attendings U = 9, p < .001), with greater exposure to LAST education (trainees U = 16.5, p < .001; attendings U = 12, p < .001). Assessment of responses to knowledge-based questions on LAST revealed a statistically significant knowledge gap between PM&R and anesthesia trainees (t = 6.62, p = <.001) as well as between attending groups (t = 3.25, p = <.01). This study reveals a distinction in both the subjective and objective knowledge of LAST between PM&R and anesthesiology physicians at a single academic institution. This suggests that there is opportunity for further assessment of the education on LAST among physiatrists and residents in training.

CRITICAL INCIDENTS AND PERIOPERATIVE EMERGENCIES: ARE FINAL YEAR RESIDENTS AND ANESTHESIOLOGISTS ARE READY?

A critical incident (CI) is any failed event that could have been prevented and carries the risk of undesirable consequences for the patient. The study of critical incidents and physicians' preparedness for their occurrence helps to reduce their consequences, risks of recurrence and improve patient safety. The aim of the study was to investigate how well are graduate residents and anesthesiologists prepare to manage critical incidents (CI) and perioperative emergencies (PE) during anesthesia. Methods and Materials: A prospective observational study was conducted at the Bogomolets National Medical University, the postgraduate department of surgery, anesthesiology and intensive care. The study was conducted from May 2022 to June 2023. Anesthesiologists and final year residents were assessed for the acquired competencies in the management of CI and PE: they conducted a self-assessment of their own competencies; passed 1 simulation scenario with an assessment on the CEХ scale during the scenario. Results. The study included 60 final year residents and 24 anesthesiologists. Many of residents (55 %) and anesthesiologists (63 %) generally assessed their readiness to manage CI and PE as high: 45% and 47% respectively considered their level of readiness to be insufficient, including 27% and 8% who assessed it as low. When stratified by the type of CI and PE, it was found that residents and anesthesiologists were best prepared to provide care in case of CI and PE from the side of breathing and airway patency cardiovascular system. Significantly worse anesthesiologists assessed their readiness for rare emergencies, such as malignant hyperthermia, anaphylaxis, local anesthetic systemic toxicity (LAST) (OR 0.35 [0.17- 0.74], p=0.009 for residents and OR 0.25 [0.07-0.8], p=0, 04 for anesthesiologists) and events related to apparatus malfunction, lack of power supply, and catching fire in the respiratory circuit (OR 0.4 [0.2-0.8], p=0.03 for residents and OR 0.25 [0.07-0.8], p=0.04 for anesthesiologists). Anesthesiologists had a significantly higher level of readiness and competence for all individual parameters and the overall mean score during simulation scenarios (7.69±0.53 vs. 5.94±1.6, p&lt;0.0001). Conclusions. Anesthesiologists generally showed higher results in readiness to manage CI and PE during anesthesia. Difficult competencies for both residents and anesthesiologists were the resource management, organizational competencies, and stress resistance.

Delayed lethal central nervous system toxicity induced by a low-dose intrathecal administration of bupivacaine: case report

Spinal anesthesia by intrathecal administration of local anesthetic (LA) is a routine practice. Local anesthetic system toxicity, occurring in the central nervous system (CNS) and cardiovascular system, is a common and life-threatening adverse event of LA through a variety of routes, but is rarely encountered in spinal anesthesia when a very low dose of LA is injected into the subarachnoid space. Here, we report a case with manifestations of delayed lethal CNS toxicity after spinal anesthesia. A 55-year-old man underwent elective repair surgery for a chronic ulcer after receiving 10 mg intrathecal administration of bupivacaine. He developed nausea, agitation, paresthesia and myoclonus on the arms, legs, and trunk, as well as a gradually reduced level of consciousness one hour after intrathecal administration. He was sedated, intubated, and transferred to the intensive care unit. Both CT and MRI scans of the brain and assessments of blood showed no abnormalities. The electroencephalogram showed spike waves occurring at electrodes C3, C4, P3, P4, and T5. The patient was sedated continuously and treated with valproate. These symptoms were completely resolved in the following days without residual neurological complications. No cardiovascular complications were observed during the entire process. The delayed lethal symptoms in this case were most likely to be CNS toxicity induced by intrathecal bupivacaine administration. CNS toxicity after spinal anesthesia may be underestimated and unpredictable and should be vigilantly cared for in clinical settings.

Continuous wound infusion catheter as part of a multimodal analgesia regimen for post-Caesarean delivery pain: a quality improvement impact study

BackgroundThe role of continuous wound infusion catheters as part of a multimodal analgesia strategy after Caesarean delivery is unclear. We introduced continuous wound infusion catheters to our multimodal analgesia regimen to evaluate the impact on analgesic outcomes after Caesarean delivery. MethodsAfter institutional review board (IRB) approval, a 4-month practice change was instituted as a quality improvement initiative. In addition to multimodal analgesia, continuous wound infusion catheters for up to 3 days were offered on alternate weeks for all women undergoing Caesarean deliveries. The primary outcome was postoperative in-hospital opioid consumption. Secondary outcomes were static and dynamic pain scores at 24 and 72 h, time until first analgesic request, opioid-related side-effects, length of stay, satisfaction (0–100%), and continuous wound infusion catheter-related complications. ResultsAll women scheduled for Caesarean delivery (n=139) in the 4-month period were included in the analysis, with 70 women receiving continuous wound infusion catheters, and 69 in the control group. Opioid consumption (continuous wound infusion catheter group 11.3 [7.5–61.9] mg morphine equivalents vs control group 30.0 [11.3–48.8] mg morphine equivalents), pain scores (except 24 h resting pain scores which were higher in the control group 2 [1–3] vs 1.5 [0–3] in the continous wound infusion catheters group; P=0.05), side-effects, length of stay, and complications were similar between groups. Satisfaction scores at 24 h were higher with continuous wound infusion catheters (100% [91–100%] vs 90% [86–100%]; P=0.003) with no differences at 72 h. One patient demonstrated symptoms of systemic local anaesthetic toxicity which resolved without significant harm. ConclusionsThe addition of continuous wound infusion catheters to a multimodal analgesia regimen for post-Caesarean delivery pain management demonstrated minimal clinically significant analgesic benefits. Future studies are needed to explore the use of continuous wound infusion catheters in populations that may benefit most from this intervention.

Local anaesthetics risks perception: A web-based survey

BackgroundThe use of local anaesthetics (LAs) is usually associated with few adverse effects, but local anaesthetic systemic toxicity (LAST) can result in serious harm and even death. However, practitioner awareness regarding this risk has been little studied. MethodsThis was a closed, web-based study carried out at two Swiss university hospitals using a fully automated questionnaire. The main objective was to evaluate LAST awareness and LA use among various medical practitioners. The secondary objective was to determine whether these physicians felt that a tool designed to compute maximum safe LA doses should be developed. ResultsThe overall participation rate was 40.2 % and was higher among anaesthesiologists (154/249, 61.8 % vs 159/530, 30.0 %; P < .001). Anaesthesiologists identified the risk of LAST and the systems involved more frequently than non-anaesthesiologists (85.1 % vs 43.4 %, P < .001). After adjusting for years of clinical experience, age, country of diploma, frequency of LA use, clinical position and being an anaesthesiologist, the only significant associations were this latter factor (P < .001) and clinical position (P = .016 for fellows and P = .046 for consultants, respectively). Most respondents supported the development of a tool designed to compute maximum safe LA doses (251/313, 80.2 %) and particularly of a mobile app (190/251, 75.7 %). ConclusionsLAST awareness is limited among practitioners who use LAs on a regular basis. Educational interventions should be created, and tools designed to help calculate maximum safe LA doses developed. The actual frequency of unsafe LA doses administration would also deserve further study.

Recognition and management of systemic toxicity of local anesthetics

Recognition and management of systemic toxicity of local anesthetics

Clinical Issues - November 2023.

Securing sterile drapes with skin staples Key words: sterile drapes, manufacturer's instructions for use, skin stapler, skin integrity, puncture wound. Sterility of rubber stoppers on medication vials Key words: rubber stopper, medication vial, alcohol swab, dust cover, contamination. Social media use in the OR Key words: social media, distractions, personal electronic device, Health Insurance Portability and Accountability Act (HIPAA), liability. Staffing for local-only anesthesia procedures Key words: staffing, RN circulator, patient acuity, monitoring, local anesthetic systemic toxicity (LAST).

Airway topicalization in pediatric anesthesia: An international cross-sectional study.

There is no national or international consensus or guideline on recommended dosing of lidocaine for airway topicalization in children. Doses quoted in the literature vary substantially. The primary aim of the study was to ascertain current international dosing practices (mg.kg-1 and concentration of solution) for lidocaine airway topicalization in children. The secondary aims included examining aftercare instructions for those receiving lidocaine airway topicalization and instances of local anesthetic systemic toxicity secondary to the use of lidocaine for airway topicalization in pediatric patients. This cross-sectional study consisted of 11-20 questions across three domains-population demographics, clinical practice, and local anesthetic systemic toxicity. It adhered to the consensus-based checklist for reporting of survey studies. Responses were collected over 14 weeks using a combination of probability (cluster and simple random) and nonprobability (purposive, convenience and snowball) sampling. Data were analyzed based on the response rate per question with proportions expressed as percentages and nonparametric data expressed as median (interquartile range [range]) in an effort to minimize nonresponse error. No weighting of items or propensity scoring was applied. After initial exclusions, 1501 participants from 69 countries, across six continents, were included. Consultant anesthetists or those with an equivalent level of experience accounted for 1262/1501 (84.1%) of responses. Results showed heterogeneity in dosing and timing regimens and evidence that dosing may contribute to adverse outcomes. The maximum dose reported by participants who use lidocaine for airway topicalization as part of their normal practice was 5 mg.kg-1 (4-6 mg.kg-1 [0.5-50]) median (interquartile range [range]) over 2 h (1-4 h [0-30]). The results support the need for further research and consensus in this area, in order to provide safe provision of lidocaine airway topicalization in children. It is hoped the results of this study can support future collaborative work in this area.

Incidents relating to paediatric regional anaesthesia in the first 8000 cases reported to webAIRS.

Regional anaesthesia is an essential tool in the armamentarium for paediatric anaesthesia. While largely safe and effective, a range of serious yet preventable adverse events can occur. Incidence and risk factors have been described, but few detailed case series exist relating to paediatric regional anaesthesia. Across Australia and New Zealand, a web-based anaesthesia incident reporting system enables voluntary reporting of detailed anaesthesia-related events in adults and children. From this database, all reports involving paediatric regional anaesthesia (age less than 17 years) were retrieved. Perioperative events and their outcomes were reviewed and analysed. When offered, the reported contributing or alleviating factors relating to the case and its management were noted. This paper provides a summary of these reports alongside an evidence review to support safe practice. Of 8000 reported incidents, 26 related to paediatric regional anaesthesia were identified. There were no deaths or reports of permanent harm. Nine reports of local anaesthetic systemic toxicity were included, seven equipment and technical issues, six errors in which regional anaesthesia made an indirect contribution and four logistical and communication issues. Most incidents involved single-shot techniques or a neuraxial approach. Common themes included variable local anaesthetic dosing, cognitive overload, inadequate preparation and communication breakdown. Neonates, infants and medically complex children were disproportionately represented, highlighting their inherent risk profile. A range of preventable incidents are reported relating to patient, systems and human factors, demonstrating several areas for improvement. Risk stratification, application of existing dosing and administration guidelines, and effective teamwork and communication are encouraged to ensure safe regional anaesthesia in the paediatric population.

Major complications of caudal block: A prospective survey of 973 cases in adult anorectal surgery

BackgroundWe conducted a prospective study of surgical inpatients at a teaching hospital to assess the incidence and potential risk factors for major complications of caudal anesthesia in anorectal surgery. MethodsA total of 973 patients undergoing anorectal surgery under caudal block were included in this prospective, observer-blinded trial after providing consent. Demographic information, detailed perioperative information, anesthesia-related complications and postoperative follow-up information were recorded. Meanwhile, the incidence and risk factors for major caudal anesthesia-related complications were analyzed. ResultsA total of 973 patients underwent caudal block. The effective rate was 95.38 % (928 cases). However, there were still 38 (3.91 %) cases with insufficient block and 7 (0.72 %) cases with no block. The major anesthesia-related complications were local anesthetic systemic toxicity (9, 0.92 %), cauda equine syndrome (1, 0.10 %), transient neurological symptoms (3, 0.31 %) and localized pain at the caudal insertion site (30, 3.08 %). The identified risk factor for local anesthetic systemic toxicity was multiple attempts locating the caudal space (OR = 5.30; 1.21–23.29). The identified risk factor for localized pain at the caudal insertion site was multiple attempts locating the caudal space (OR = 10.57; 4.89–22.86). ConclusionThe main complications of caudal block in adult patients are transient neurological symptoms, cauda equine syndrome, serious local anesthetic systemic toxicity and localized pain at the caudal insertion site. Overall, the incidence of complications is low and symptoms are mild. Caudal block is still a safe and reliable method for anesthesia in adult anorectal surgery.

Three Cases of Local Anesthetic Systemic Toxicity following regional infiltration analgesia: The need for prompt recognition and treatment

Introduction: The diagnosis and management of systemic toxicity in patients following regional infiltration analgesia is of paramount importance. While the mechanism and risk factors have been elucidated in previous studies, we believe that due to the potentially life-threatening nature of this rare occurrence, a greater focus on diagnostic precision and management enhancements is warranted. Cases: Here, we describe three cases of LAST, the first in a 59 year old female following elective L4-L5 laminectomy and L5-S1 fusion, who suffered a cardiac arrest after receiving local Exparel and Marcaine at the time of closure; the second in a 69 year old woman following a rib block using local Exparel and Marcaine for the management of multiple rib fractures, who had a witnessed tonic-clonic seizure requiring intubation. The third patient is an 80-year-old male, who after an elective L4-L5 laminectomy and fusion, suffered a cardiac arrest after receiving local anesthetic (Exparel and Marcaine) at the time of closure. All patients were treated with intralipids and eventually recovered with no lasting deficits. Conclusion: LAST events most commonly occur in the first minutes after injection, and are characterized by CNS and cardiovascular toxicities, as seen in these patients. Delayed presentations up to several days post exposure have been described. These cases exposed the opportunity for education in early recognition and most important, the need to improve the availability of intralipids. Prompt recognition and access to intralipid is critical to the treatment of LAST, and education regarding this rare but life-threatening condition is needed in surgical and trauma centers.