Scaling Emergency Department Opioid Use Disorder Treatment Across California to Reduce Overdose Deaths, 2019-2023.

Since April 2019, CA Bridge has worked with emergency departments (EDs) in diverse geographic and emergency care settings across California to scale up low-threshold buprenorphine access, patient navigation programs, harm reduction services, and take-home naloxone. Between April 2019 and June 2023, 268 (81.0%) of 331 acute care hospitals in California received funding and technical assistance from CA Bridge and completed data reporting. These hospitals provided navigation services during 279 025 patient encounters and gave patients buprenorphine in 89 549 ED visits. (Am J Public Health. 2024;114(9):874-878. https://doi.org/10.2105/AJPH.2024.307710).

Leveraging a Learning Collaborative Model to Develop and Pilot Quality Measures to Improve Opioid Prescribing in the Emergency Department.

The American College of Emergency Physicians (ACEP) Emergency Medicine Quality Network (E-QUAL) Opioid Initiative was launched in 2018 to advance the dissemination of evidence-based resources to promote the care of emergency department (ED) patients with opioid use disorder. This virtual platform-based national learning collaborative includes a low-burden, structured quality improvement project, data benchmarking, tailored educational content, and resources designed to support a nationwide network of EDs with limited administrative and research infrastructure. As a part of this collaboration, we convened a group of experts to identify and design a set of measures to improve opioid prescribing practices to provide safe analgesia while reducing opioid-related harms. We present those measures here, alongside initial performance data on those measures from a sample of 370 nationwide community EDs participating in the 2019 E-QUAL collaborative. Measures include proportion of opioid administration in the ED, proportion of alternatives to opioids as first-line treatment, proportion of opioid prescription, opioid pill count per prescription, and patient medication safety education among ED visits for atraumatic back pain, dental pain, or headache. The proportion of benzodiazepine and opioid coprescribing for ED visits for atraumatic back pain was also evaluated. This project developed and effectively implemented a collection of 6 potential measures to evaluate opioid analgesic prescribing across a national sample of community EDs, representing the first feasibility assessment of opioid prescribing-related measures from rural and community EDs.

Effectiveness of Substance Use Navigation for Emergency Department Patients With Substance Use Disorders: An Implementation Study.

STUDY OBJECTIVE: We implemented a whole person care-informed intervention delivered by substance use navigators (SUN) for emergency department (ED) patients with substance use disorders. METHODS: This was an implementation study of adult patients discharged from 3 public hospital EDs between September 1, 2021 through January 31, 2022 with cocaine, methamphetamine, alcohol, and opioid use-related diagnoses. The primary effectiveness outcome was treatment engagement within 30 days of ED discharge among patients with and without the SUN intervention. We used logistic regression and nearest neighbor propensity score matching without replacement to control for confounding effects. RESULTS: There were 1,328 patients in the cohort, and 119 (9.0%) received the SUN intervention; 50.4% of patients in the SUN intervention group and 15.9% of patients without the SUN intervention were engaged in outpatient treatment within 30 days of ED discharge (difference in proportions: 34.5%, 95% confidence interval [CI] 25.3% to 43.8%). In the unadjusted analysis, the SUN intervention was associated with higher rates of treatment engagement after ED discharge for patients with alcohol, opioid, and cocaine-related diagnoses; patients with methamphetamine-related diagnoses had low engagement rates with or without the SUN intervention. In addition, the SUN intervention was associated with higher odds of treatment engagement in the multivariable model (aOR 3.7, 95% CI 2.4 to 5.8) and in the propensity score-matched analysis (OR 2.1, 95% CI 1.2 to 3.5). CONCLUSION: A whole person care-informed intervention delivered by SUNs for ED patients with substance use disorders was strongly associated with higher engagement rates in addiction treatment after discharge.

National Institute on Drug Abuse Clinical Trials Network Meeting Report: Advancing Emergency Department Initiation of Buprenorphine for Opioid Use Disorder.

Opioid use disorder and opioid overdose deaths are a major public health crisis, yet highly effective evidence-based treatments are available that reduce morbidity and mortality. One such treatment, buprenorphine, can be initiated in the emergency department (ED). Despite evidence of efficacy and effectiveness for ED-initiated buprenorphine, universal uptake remains elusive. On November 15 and 16, 2021, the National Institute on Drug Abuse Clinical Trials Network convened a meeting of partners, experts, and federal officers to identify research priorities and knowledge gaps for ED-initiated buprenorphine. Meeting participants identified research and knowledge gaps in 8 categories, including ED staff and peer-based interventions; out-of-hospital buprenorphine initiation; buprenorphine dosing and formulations; linkage to care; strategies for scaling ED-initiated buprenorphine; the effect of ancillary technology-based interventions; quality measures; and economic considerations. Additional research and implementation strategies are needed to enhance adoption into standard emergency care and improve patient outcomes.

Prehospital Buprenorphine Treatment for Opioid Use Disorder by Paramedics: First Year Results of the EMS Buprenorphine Use Pilot.

BACKGROUND: Prehospital initiation of buprenorphine treatment for Opioid Use Disorder (OUD) by paramedics is an emerging potential intervention to reach patients at greatest risk for opioid-related death. Emergency medical services (EMS) patients who are at high risk for overdose deaths may never engage in treatment as they frequently refuse transport to the hospital after naloxone reversal. The potentially important role of EMS as the initiator for medication for opioid use disorder (MOUD) in the most high-risk patients has not been well described. SETTING: This project relies on four interventions: a public access naloxone distribution program, an electronic trigger and data sharing program, an "Overdose Receiving Center," and a paramedic-initiated buprenorphine treatment. For the final intervention, paramedics followed a protocol-based pilot that had an EMS physician consultation prior to administration. RESULTS: There were 36 patients enrolled in the trial study in the first year who received buprenorphine. Of those patients receiving buprenorphine, only one patient signed out against medical advice on scene. All other patients were transported to an emergency department and their clinical outcome and 7 and 30 day follow ups were determined by the substance use navigator (SUN). Thirty-six of 36 patients had follow up data obtained in the short term and none experienced any precipitated withdrawal or other adverse outcomes. Patients had a 50% (18/36) rate of treatment retention at 7 days and 36% (14/36) were in treatment at 30 days. CONCLUSION: In this small pilot project, paramedic-initiated buprenorphine in the setting of data sharing and linkage with treatment appears to be a safe intervention with a high rate of ongoing outpatient treatment for risk of fatal opioid overdoses.

URINE TOXICOLOGY PROFILES OF EMERGENCY DEPARTMENT PATIENTS WITH UNTREATED OPIOID USE DISORDER: A MULTI-SITE VIEW.

BACKGROUND: Opioid overdose deaths in 2021 were the highest ever, driven by fentanyl and polysubstance use. OBJECTIVE: The aim of the study was to characterize drug use, assessed by urine drug screens (UDSs), in patients with untreated opioid use disorder (OUD) presenting to 28 emergency departments (EDs) nationally and by region. METHODS: We analyzed UDSs from patients enrolled in the CTN-0099 ED-INNOVATION (Emergency Department-Initiated Buprenorphine Validation) trial between July 12, 2020 and March 9, 2022. Participants were adult ED patients with OUD not engaged in addiction treatment with a UDS positive for an opioid, but negative for methadone. Sites were divided into "East" and "West" regions. RESULTS: A UDS was available for all 925 enrolled participants, 543 from East and 382 from West. Fentanyl was in 702 specimens (76%) (n = 485 [89%] East vs. n = 217 [57%] West; p < 0.01) and was the only opioid in 269 (29%). After fentanyl, the most common opioids were morphine (presumably heroin; n = 411 [44%]; n = 192 [35%] East vs. n = 219 [57%] West; p < 0.01) and buprenorphine (n = 329 [36%]; n = 186 [35%] East vs. n = 143 [37%] West; p = 0.32). The most common drugs found with opioids were stimulants (n = 545 [59%]), tetrahydrocannabinol (n = 417 [45%]), and benzodiazepines (n = 151 [16%]). Amphetamine-type stimulants were more common in West (n = 209 [55%] vs. East (n = 125 [23%]). Cocaine was more common in East (n = 223 [41%]) vs. West (n = 82 [21%]). The presence of multiple drugs was common (n = 759 [82%]). CONCLUSIONS: Most participants had UDS specimens containing multiple substances; a high proportion had fentanyl, stimulants, and buprenorphine. Regional differences were noted. Given the increased risk of death with fentanyl and polysubstance use, ED providers should be providing risk reduction counseling, treatment, and referral.

A Neuropharmacological Model to Explain Buprenorphine Induction Challenges.

Buprenorphine induction for treating opioid use disorder is being implemented in emergency care. During this era of high-potency synthetic opioid use, novel and divergent algorithms for buprenorphine induction are emerging to optimize induction experience, facilitating continued treatment. Specifically, in patients with chronic fentanyl or other drug exposures, some clinicians are using alternative buprenorphine induction strategies, such as quickly maximizing buprenorphine agonist effects (eg, macrodosing) or, conversely, giving smaller initial doses and slowing the rate of buprenorphine dosing to avoid antagonist/withdrawal effects (eg, microdosing). However, there is a lack of foundational theory and empirical data to guide clinicians in evaluating such novel induction strategies. We present data from clinical studies of buprenorphine induction and propose a neuropharmacologic working model, which posits that acute clinical success of buprenorphine induction (achieving a positive agonist-to-withdrawal balance) is a nonlinear outcome of the opioid balance at the time of initial buprenorphine dose and mu-opioid-receptor affinity, lipophilicity, and mu-opioid-receptor intrinsic efficacy (the "ALE value") of the prior opioid. We discuss the rationale for administering smaller or larger doses of buprenorphine to optimize the patient induction experience during common clinical situations.

Prehospital Initiation of Buprenorphine Treatment for Opioid Use Disorder by Paramedics.

Prehospital initiation of buprenorphine treatment for Opioid Use Disorder (OUD) by paramedics is an emerging potential intervention. Many patients who may be at high risk for overdose deaths may never engage in treatment because they frequently refuse transport. Recent data have demonstrated a significant increase in both short and long term mortality following an opioid overdose. We describe 3 preliminary cases with a novel intervention of initiating Buprenorphine in the prehospital setting for symptoms of opioid withdrawal, regardless of etiology. In addition, we describe tracking of long term engagement in additional services as part of an integrated approach to combatting the opioid epidemic through EMS focused interventions.

Implementation of Oral and Extended-Release Naltrexone for the Treatment of Emergency Department Patients With Moderate to Severe Alcohol Use Disorder: Feasibility and Initial Outcomes.

STUDY OBJECTIVE: Despite evidence supporting naltrexone as an effective treatment for alcohol use disorder, its use in emergency department (ED) patients has not been described. We implemented a protocol that combined substance use navigation with either oral naltrexone or extended-release intramuscular naltrexone for patients with alcohol use disorder as a strategy to improve follow-up in addiction treatment after ED discharge. METHODS: In this descriptive study, we analyzed the results from adult patients discharged from the ED with moderate to severe alcohol use disorder who received either oral naltrexone or extended-release intramuscular naltrexone between May 1, 2020, and October 31, 2020, and assessed their engagement in formal addiction treatment within 30 days after discharge from the ED. RESULTS: Among 59 patients with moderate to severe alcohol use disorder who accepted naltrexone treatment, 41 received oral naltrexone and 18 received extended-release intramuscular naltrexone. The mean (SD) age of the patients was 45.2 (13.4) years; 22 patients (37.3%) were Latinx, 18 (30.5%) were Black, and 16 (27.1%) were White. Among all patients, 9 (15.3%) attended follow-up formal addiction treatment within 30 days after discharge; 5 patients (27.8%) who received extended-release intramuscular naltrexone and 4 patients (9.8%) who received oral naltrexone attended follow-up treatment within 30 days. CONCLUSION: We implemented a clinical protocol for ED patients with moderate to severe alcohol use disorder using oral naltrexone and extended-release intramuscular naltrexone together with substance use navigation. Identification of alcohol use disorder, a brief intervention, and initiation of naltrexone resulted in a 15% follow-up rate in formal addiction treatment. Future work should prospectively examine the effectiveness of naltrexone as well as the effect of substance use navigation for ED patients with alcohol use disorder.

Rapid Adoption of Low-Threshold Buprenorphine Treatment at California Emergency Departments Participating in the CA Bridge Program.

STUDY OBJECTIVE: We retrospectively evaluated the implementation of low-threshold emergency department (ED) buprenorphine treatment at 52 hospitals participating in the CA Bridge Program using the RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework. METHODS: The CA Bridge model included low-threshold buprenorphine, connection to outpatient care, and harm reduction. Implementation began in March 2019. Participating hospitals reported aggregated clinical data monthly after program initiation. Outcomes included identification of opioid use disorder, buprenorphine administration, and linkage to outpatient addiction treatment. Multivariable models assessed associations between hospital location (rural versus urban) and teaching status (clinical teaching hospital versus community hospital) and outcomes in adopting the CA Bridge Program. RESULTS: Reach: A diverse and geographically distributed group of 52 California hospitals were enrolled in 2 phases (March and August 2019); 12 (23%) were rural and 13 (25%) were teaching hospitals. Effectiveness: Over a 14-month implementation period, 12,009 opioid use disorder patient encounters were identified, including 7,179 (59.7%) where buprenorphine was administered and 4,818 (40.1%) where follow-up visits were attended. Adoption: In multivariable analysis, adoption did not differ significantly between rural and urban or teaching and nonteaching hospitals. IMPLEMENTATION: By program completion, all 52 (100%) hospitals treated opioid use disorder with buprenorphine; 45 (86.5%) administered buprenorphine after naloxone reversal; 41 (84.6%) offered buprenorphine for inpatients; 48 (92.3%) initiated buprenorphine in pregnant women; and 29 (55.8%) offered take-home naloxone. Maintenance: At 8-month follow-up, all 52 sites reported continued buprenorphine treatment. CONCLUSION: Low-threshold ED buprenorphine treatment implemented with a harm reduction approach and active navigation to outpatient addiction treatment was successful in achieving buprenorphine treatment for opioid use disorder in diverse California communities.

Overdose Receiving Centers - An Idea Whose Time Has Come?

Drug overdose deaths have been the leading cause of accidental death in the United States with two thirds involving opioids. Strong evidence supports the efficacy of medications for addiction treatment such as buprenorphine and harm reduction strategies such as naloxone distribution. While emergency medical service (EMS) systems have defined specialty centers for the treatment of many significant life threatening disease (trauma, stroke, myocardial infarction) implementation of opioid use disorder systems of care that integrate EMS are uncommon. As fentanyl drives the third wave of the opioid epidemic, EMS systems are uniquely positioned to direct patients to hospitals that can provide the best care for patients with Opiate Use Disorder (OUD.) Emergency Departments which have established systems for early intervention and treatment for patients with opioid use disorders have shown higher engagement in treatment programs. This, in turn, leads to lower mortality. EMS systems which designate specialty centers for overdose patients may show a public health mortality benefit.

Treatment of opioid and alcohol withdrawal in a cohort of emergency department patients.

BACKGROUND: The safety of combining buprenorphine with a benzodiazepine or barbiturate in the treatment of concurrent alcohol and opioid withdrawal has not been well established. In this study we examine a cohort of patients treated with buprenorphine and phenobarbital or benzodiazepines for co-occurring opioid and alcohol withdrawal. METHODS: This is a retrospective cohort study of ED patients treated for opioid and alcohol withdrawal from January through December 2018. The primary outcome was unexpected airway intervention, or the administration of naloxone for respiratory depression. RESULTS: There were 16 patients treated for opioid and alcohol withdrawal. The mean age was 44.3 (standard deviation [SD] 13.1), 12 (75.0%) were male, and 8 (50.0%) of the patients were admitted to the hospital. For opioid withdrawal, six patients received intravenous buprenorphine, with doses between 0.3 mg to 1.8 mg; 12 patients received sublingual buprenorphine, with doses between 4 mg to 32 mg. For alcohol withdrawal, 10 patients received lorazepam with doses between 1 mg and 8 mg; 10 patients received phenobarbital with doses between 260 mg to 1040 mg. There were no unexpected airway interventions related to medications used for opioid or alcohol withdrawal. One patient with severe pneumonia was an expected intubation for respiratory failure. CONCLUSIONS: We describe a cohort of patients treated for opioid and alcohol withdrawal in the ED. There were no serious adverse events related to the medications used to treat opioid or alcohol withdrawal. Further work should assess optimal use of medical therapy for opioid and alcohol withdrawal and the transition to maintenance treatment for substance use disorders.

A Nonopioid, Nonbenzodiazepine Treatment Approach for Intractable Nausea and Vomiting in the Emergency Department.

GOAL: We sought to assess the feasibility and efficacy of a treatment protocol for nausea and vomiting using the combination of chlorpromazine, a dopamine antagonist antiemetic, and ketamine, a nonopioid analgesic. BACKGROUND: Increasing numbers of patients with cannabis use disorder are presenting to emergency departments with a poorly understood syndrome characterized by intractable nausea and vomiting. METHODS: This is a prospective, observational study involving a convenience sample of patients with unexplained nausea and vomiting. Subjects were given ketamine 15 mg slow intravenous push and chlorpromazine 12.5 mg intravenous over 15 minutes. Outcomes were number of episodes of emesis after study drug administration; change in nausea severity; change in pain severity; adverse events; and patient satisfaction. RESULTS: We enrolled 28 subjects on 30 emergency department visits. Twenty-three subjects (82%) reported at least weekly cannabis use with 19 reporting daily use. Initial symptoms were severe, with median pain and nausea scores both 10. After receiving study medication, the mean decrease in pain score over 120 minutes was 4.1 (95% confidence interval: 3.2, 5.0) and the mean decrease in nausea score was 4.9 (95% confidence interval: 4.0, 5.8). There were no adverse events. All 28 subjects who were asked reported they would want to receive these medications again. CONCLUSION: In this single-center study, the majority of patients presenting with intractable nausea and vomiting reported heavy cannabis use, and symptoms were severe. The combination of chlorpromazine plus ketamine resulted in rapid, definitive cessation of symptoms in most of these patients without the need for opioids or benzodiazepines.

Successful emergency pain control for acute pancreatitis with ultrasound guided erector spinae plane blocks.

Pain control for patients in the Emergency Department (ED) with acute pancreatitis (AP) can be difficult and is often limited to intravenous opioids. The acute side effects from opioids are well known and their use in the treatment of AP is associated with prolonged length of hospitalization. Additionally, up to 10% of patients hospitalized for acute pancreatitis are still receiving opioids 6 months after discharge. Ultrasound-guided regional anesthesia by emergency physicians has increasingly proven to be an integral part of a multi-modal opioid sparing pain control strategy for patients in the ED. The ultrasound guided erector spinae plane block may be an ideal adjunct or alternative to opioids for analgesia from AP in the ED. The erector spinae plane block has already been successfully utilized by emergency physicians for pain control from rib fractures, herpes zoster, and more recently, acute appendicitis A lower thoracic erector spinae plane block targets sympathetic nerve fibers in addition to the dorsal and ventral rami via local anesthetic spread to the paravertebral space to provide both visceral and somatic analgesia. Herein, we present the first reported case of acute pancreatitis pain successfully managed by emergency physicians with the ESPB.

Circadian Profile of an Emergency Medicine Department: Scheduling Practices and Their Effects on Sleep and Performance.

BACKGROUND: Shiftwork causes circadian disruption and is the primary reason for attrition from Emergency Medicine. OBJECTIVES: We aimed to develop concrete recommendations to mitigate negative effects of shiftwork based on measures of work, sleep, alertness, and performance in emergency physicians. METHODS: Thirty-one Emergency Medicine residents were surveyed retrospectively about sleep and alertness on different shifts. Additionally, the sleep, performance, and alertness of 22 Emergency Medicine resident and attending physicians was tracked continuously over 4 weeks via sleep logs, actigraphy, real-time reported sleepiness, and performance on a vigilance task. Schedules were analyzed for circadian disruption. Physicians also predicted their sleep schedules, which were compared with actual schedules; participants tracked extensions of shifts, schedule changes, and shifts in other hospitals. RESULTS: Daily rhythms were apparent in real-time performance and alertness data, with peaks at around 4 pm. Sleep difficulty was highest, sleep shortest, and alertness and performance lowest for night shifts. Emergency Medicine residents tended to cluster multiple night shifts in a row, despite evidence of accumulating sleep debt over consecutive shifts. There were many shifts that caused high circadian disruption, which could be avoided by simple amendments to scheduling practices. CONCLUSIONS: Circadian principles should be applied as suggested by the American College of Emergency Physicians. Chronotype should be considered in scheduling. Night shifts, particularly, should not be extended. Clustering all night shifts in a row should probably be discouraged. The additional vulnerabilities for night shift could be mitigated by adopting napping mid- or post night shift and by providing pay differentials.

Intravenous Lidocaine Provides Similar Analgesia to Intravenous Morphine for Undifferentiated Severe Pain in the Emergency Department: A Pilot, Unblinded Randomized Controlled Trial.

OBJECTIVES: We compared the analgesic effects of intravenous (IV) lidocaine and IV morphine for the treatment of severe pain in the emergency department (ED). METHODS: This was a pilot, unblinded randomized controlled study comparing the efficacy of IV lidocaine vs IV morphine for patients aged ≥18 years with severe pain (numerical rating scale [NRS] ≥ 7). Participants were randomized to receive IV lidocaine (75 mg if <50 kg, 100 mg if 50-100 kg, and 150 mg if >100 kg) over 10 minutes, followed by a 50-minute IV lidocaine infusion of the same dose or provider-chosen dose of morphine. Participants were eligible for rescue morphine. The primary outcome was the difference in patients' mean reported pain at 60 minutes. Secondary outcomes included total morphine consumption, patient satisfaction, and side effects. RESULTS: Thirty-two patients were enrolled. The lidocaine arm's mean pain NRS at 60 minutes was 5.1 (95% confidence interval [CI] = 3.3 to 6.8) compared with 4.2 (95% CI = 3.0 to 5.4) in the morphine arm, and the absolute difference was 0.9 (95% CI = -1.2 to 2.9). Among participants in the lidocaine and morphine arms, 13% and 38%, respectively, had side effects. Patient satisfaction was similar in both arms (87% and 88%). Lidocaine arm patients averaged 4.5 mg of IV morphine (95% CI = 3.0 to 6.0) compared with 8.4 mg (95% CI = 6.9 to 9.8) in the morphine arm, an absolute difference of 3.9 mg (95% CI = 1.8 to 5.9). CONCLUSIONS: We found similar pain relief and satisfaction in both study arms. Lidocaine arm participants had fewer side effects and required less morphine. Lidocaine is a potential opioid-sparing analgesic that deserves further study for severe pain in ED patients.

Computed Tomography Use Plateaus Among Children With Emergency Visits for Abdominal Pain.

OBJECTIVES: Abdominal pain is a common pediatric complaint to emergency departments (EDs), and clinicians often rely on imaging for diagnosis. Studies have demonstrated an increase in computed tomography (CT) in this population. Following emphasis on radiation reduction by researchers and organizations, this study evaluates recent national trends in CT use among pediatric patients presenting to EDs with abdominal pain. METHODS: This is a cross-sectional analysis of ED patients 18 years or younger with chief complaint of abdominal pain in the National Hospital Ambulatory Medical Care Survey from 2008 to 2011. Outcomes include annual proportions of visits with x-ray, ultrasound, or CT, as well as diagnosis of appendicitis and hospital admission. RESULTS: Of 32,304 ED visits, 2120 (6.6%) were for abdominal pain. Proportions of visits using CT, ultrasound, and plain x-ray were 16.0%, 10.5%, and 23.4%, respectively. For all outcome measures, including imaging, hospital admission, and diagnosis of appendicitis, there was no change from 2008 to 2011. Considering previous data, there was a significant rise in ultrasound use from 5.4% (95% confidence interval, 2.4%-8.4%) in 1998 to 12.1% (95% confidence interval, 9.4%-13.7%) in 2011. Multivariate analysis of CT use found the strongest predictor to be increasing age. Females, black children, and those with Medicaid insurance had lower odds of having a CT. CONCLUSIONS: In contrast to the earlier dramatic increase in CT use for pediatric patients with abdominal pain, CT remained constant between 2008 and 2011. There was no associated change in the rate of diagnosis of appendicitis or hospitalization; however, ultrasound is increasing.

Interplay Between Hydroxyl Density and Relaxations in Poly(vinylbenzyltrimethylammonium)-b-poly(methylbutylene) Membranes for Electrochemical Applications.

Anion-exchange membranes (AEMs) consisting of poly(vinyl benzyl trimethylammonium)-b-poly(methylbutylene) of three different ion exchange capacities (IECs), 1.14, 1.64, and 2.03 mequiv g-1, are studied by High-Resolution Thermogravimetry, Modulated Differential Scanning Calorimetry, Dynamic Mechanical Analysis, and Broadband Electrical Spectroscopy in their OH- form. The thermal stability and transitions are elucidated, showing a low temperature Tg and a higher temperature transition assigned to a disorder-order transition, Tδ, which depends on the IEC of the material. The electric response is analyzed in detail, allowing the identification of three polarizations (only two of which contribute significantly to the overall conductivity, σEP and σIP,1) and two dielectric relaxation events (ß1 and ß2), one associated with the tolyl side groups (ß1) and one with the cationic side chains (ß2). The obtained results are integrated in a coherent picture and a conductivity mechanism is proposed, involving two distinct conduction pathways, σEP and σIP,1. Importantly, we observed a reordering of the ion pair dipoles which is responsible for the Tδ at temperatures higher than 20 °C, which results in a dramatic decrease of the ionic conductivity. Clustering is highly implicated in the higher IEC membrane in the hydroxyl form, which reduces the efficiency of the anionic transport.

Successful emergency pain control for posterior rib fractures with ultrasound-guided erector spinae plane block.

The Eastern Association for the Surgery of Trauma and Trauma Anesthesiology Society Guidelines recommend prompt and effective multimodal analgesia for rib fractures that combines regional anesthesia (RA) techniques with pharmacotherapy to treat pain, optimize pulmonary function, and reduce opioid related complications. However, RA techniques such as epidurals and paravertebral blocks, are generally underutilized or unavailable for emergency department (ED) patients. The recently described serratus anterior plane block (SAPB) is a promising technique, but failures with posterior rib fractures have been observed. The erector spinae plane block (ESPB) is conceptually similar to the SAPB, but targets the posterior thorax making it likely more effective for ED patients with posterior rib fractures. Our initial experience demonstrates consistent success with the ESPB for traumatic posterior rib fracture analgesia. Herein, we present the first description of the ESPB utilized in the ED.

Quantum-Mechanical Study of the Reaction Mechanism for 2π-2π Cycloaddition of Fluorinated Methylene Groups.

Perfluorocyclobutyl polymers are thermally and chemically stable, may be produced without a catalyst via thermal 2π-2π cycloaddition, and can form block structures, making them suitable for commercialization of specialty polymers. Thermal 2π-2π cycloaddition is a rare reaction that begins in the singlet state and proceeds through a triplet intermediate to form an energetically stable four-membered ring in the singlet state. This reaction involves two changes in spin state and, thus, two spin-crossover transitions. Presented here are density functional theory calculations that evaluate the energetics and reaction mechanisms for the dimerizations of two different polyfluorinated precursors, 1,1,2-trifluoro-2-(trifluoromethoxy)ethane and hexafluoropropylene. The spin-crossover transition states are thoroughly investigated, revealing important kinetics steps and an activation energy for the gas-phase cycloaddition of two hexafluoropropene molecules of 36.9 kcal/mol, which is in good agreement with the experimentally determined value of 34.3 kcal/mol. It is found that the first carbon-carbon bond formation is the rate-limiting step, followed by a rotation about the newly formed bond in the triplet state that results in the formation of the second carbon-carbon bond. Targeting the rotation of the C-C bond, a set of parameters were obtained that best produce high molecular weight polymers using this chemistry.