Management of opioid analgesic overdose

Impact of UNODC/WHO S-O-S (stop-overdose-safely) training on opioid overdose knowledge and attitudes among people at high or low risk of opioid overdose in Kazakhstan, Kyrgyzstan, Tajikistan and Ukraine

INTRODUCTION

Opioid overdose education and naloxone distribution (OEND) is an evidence-based strategy to reduce opioid overdose deaths in line with guidance provided by the World Health Organization (WHO) and United Nations Office on Drugs and Crime (UNODC). However, OEND effectiveness has rarely been examined in low- and middle-income countries (LMICs). The WHO/UNODC Stop Overdose Safely (S-O-S) project involved training of > 14,000 potential opioid overdose witnesses in opioid overdose response (including the administration of naloxone) in Kazakhstan, Kyrgyzstan, Tajikistan and Ukraine. We examined the impact of training using the S-O-S training package, developed within the framework of the S-O-S project, on knowledge of and attitudes towards, opioid overdose as well as effective opioid overdose response amongst participants stratified by high and low personal risk of opioid overdose.

DESIGN AND METHODS

A sample of S-O-S project participants were recruited into a cohort study to evaluate the effects of training using the S-O-S training package. Of these participants, 1481 at high or low personal risk of opioid overdose completed pre- and post-S-O-S training questionnaires that incorporated sections of the Brief Opioid Overdose Knowledge (BOOK) and Opioid Overdose Attitudes Scale (OOAS) instruments. Outcomes examined included overall scale scores as well as scores on instrument sub-scales. Mean change scores, stratified by personal risk of opioid overdose, were calculated and compared using repeated measures t-tests. Variation in overall change scores according to select participant characteristics (e.g., age, sex) was also examined using multivariable linear regression.

RESULTS

After training there were increases in overall BOOK and OOAS mean scores with a similar pattern evident in mean scores for all instrument subscales. Observed changes were larger for participants at low personal risk of opioid overdose (between 11% and 112%, depending on measure) compared to those who were at high personal risk of overdose (between 5% and 33% depending on measure), reflecting higher baseline scores for those at high personal risk of opioid overdose. We observed few variations in change scores across other participant characteristics. However, amongst those at high personal risk of opioid overdose, no personal experience of an overdose (β=-0.3; 95%CI=-0.5-0) and not currently being in drug treatment (β=-0.6; 95%CI=-0.4-0.8) was associated with a higher BOOK change score. Reporting not having witnessed an overdose previously was associated with higher BOOK change scores amongst those at low personal opioid overdose risk (β = 0.5; 95%CI = 0.2-0.8). Not currently being in drug treatment (β=-1.3; 95%CI=-0.1-2.4) was associated with a higher OOAS change score amongst those at high personal risk of opioid overdose.

DISCUSSION

OEND training using the S-O-S training package resulted in substantial improvements in knowledge and attitudes related to opioid overdose and responses in the four countries, with improvements most notable amongst those at lower personal risk of opioid overdose. Widespread implementation of OEND using the S-O-S training package or similar could improve opioid overdose response in LMICs.

Investigation of powder properties and application aspects impacting nasal deposition of spray dried powders in a nasal cast

In this study, spray-dried formulations differing in morphology (spherical and wrinkled), surface polarity (hydrophilic and hydrophobic), and size (20-30 µm and 3 µm) were evaluated in a nasal cast to assess their deposition profiles. The objective was to identify how formulation properties and application aspects influence the deposition profile. For this purpose, the formulations were administered at different application angles (45° and 60°), fill weights (20 mg and 40 mg), and airflow rates (0 L/min and 15 L/min) in conjunction with a UDS powder device. The results indicate a more posterior deposition profile for 45° compared to 60° due to increased deposition in the turbinate region; conversely, deposition profiles between fill weights were comparable. Application with simultaneous airflow should be avoided because of an increasing postnasal fraction. No influence of morphology could be observed, but for the surface polarity an influence was apparent, if the powder was applied with a simulated inspiration. In these cases, a hydrophobic formulation was better dispersible than a hydrophilic formulation, which led to an increased postnasal fraction. A particle size for pulmonary application demonstrated comparable results to nasal formulations with respect to the turbinate deposition but exhibited a high postnasal fraction for hydrophobic formulations.

Predictive modeling of methadone poisoning outcomes in children ≤ 5 years: utilizing machine learning and the National Poison Data System for improved clinical decision-making

The escalating therapeutic use of methadone has coincided with an increase in accidental ingestions, particularly among children ≤ 5 years. This study utilized machine learning (ML) methodologies on data from the National Poison Data System (NPDS) to predict pediatric methadone poisoning outcomes to enhance clinical decision-making. We analyzed 140 medical parameters from pediatric patient records. Pre-processing steps, including synthetic oversampling, addressed the imbalanced distribution of the outcome variable. We evaluated various ML models in multiclass classification tasks. Random forest showed versatility with an accuracy of 0.96 and a strong receiver operating characteristic area under the curve (ROC AUC) (0.98). Meanwhile, the support vector machine (SVM) had the highest negative predictive value (NPV) (0.64). Shapley Additive exPlanation (SHAP) analysis identified key predictors such as coma, cyanosis, respiratory arrest, and respiratory depression for predicting serious outcomes.

CONCLUSION

This research emphasizes the utility of ML in clinical settings for early detection and intervention in methadone poisoning events in children, highlighting the synergy between data science and clinical expertise.

WHAT IS KNOWN

• The increased use of methadone for treatment has been associated with a rise in accidental ingestions, particularly in children under five years old. • Methadone poisoning in young children can lead to severe outcomes, including respiratory depression and coma, requiring urgent medical intervention.

WHAT IS NEW

• Machine learning models, particularly Random Forest and Bagging, outperform traditional methods in predicting methadone poisoning outcomes in children. • SHAP analysis provides novel insights into key predictors of severe outcomes, enabling improved clinical decision-making and risk stratification.

Poisoning and overdose at a glance

Poisoning and overdose are significant public health concerns in the UK, with poisoning accounting for more than 115000 hospital presentations in England in 2021-2022. Nurses are crucial in managing patients from triage to discharge. Nurses' role in treating poisoning and overdose cases involves recognising toxidromes, initial stabilisation and symptom management. Commonly ingested substances include paracetamol, ibuprofen and illicit drugs; pharmacological interventions available include antidotes such as acetylcysteine and naloxone. Patients require a multidisciplinary approach, and collaborative care may involve clinical toxicologists, mental health professionals and social services to ensure comprehensive recovery. Ethical considerations of poisoning treatment include patient consent and the complexities of intentional overdoses. By understanding the nuances of poisoning and overdose treatment, health professionals can offer compassionate, evidence-based care.

Intranasal overdose reversal formulations: a rapid review of available agents

The opioid epidemic continues to pose a significant threat to public health. Naloxone, a potent opioid antagonist, has proven to be a crucial tool in reversing opioid overdoses. Efforts to increase access to overdose reversal agents, initially given by injection in hospitals and emergency environments, resulted in the development of intranasal (IN) forms of naloxone, and more recently, nalmefene. This rapid review examines the currently available IN overdose reversal agents in the United States, focusing on their dosing, efficacy, and prescription status.We conducted a comprehensive search of the FDA Electronic Drug and Listing System (eDRLS) to identify all approved naloxone and nalmefene formulations in 2024. The search yielded nine available overdose reversal agents, including generic formulations of naloxone available over the counter and accessible to the public. Additionally, newer agents, such as nalmefene, offer longer-acting effects and may provide additional benefits in certain overdose scenarios.As the opioid crisis evolves, it is essential to stay informed about the latest advancements in formulations of reversal agents. By understanding the characteristics and availability status of available agents, health care providers, public health officials, and individuals can make informed decisions about the most appropriate overdose treatment strategies.

Opioid-induced respiratory depression: clinical aspects and pathophysiology of the respiratory network effects

Important insights and consensus remain lacking for risk prediction of opioid-induced respiratory depression (OIRD), reversal of respiratory depression (RD), the pathophysiology of OIRD, and which sites make the most significant contribution to its induction. The ventilatory response to inhaled carbon dioxide is the most sensitive biomarker of OIRD. To accurately predict respiratory depression (RD), a multivariant RD prospective trial using continuous capnography and oximetry examining five independent variables, age ≥60, sex, opioid naivety, sleep disorders, and chronic heart failure (PRODIGY trial), were undertaken. Intermittent oximetry alone substantially underestimates the incidence of RD. Naloxone, with an elimination half-life of ∼33 min (cf. morphine 2-3 h; fentanyl and congeners only 5-15 min), has limitations for the rescue of patients with severe OIRD. Buprenorphine is potentially valuable in patients being treated long term since its high µ-receptor (MOR) affinity makes it difficult for an opioid of lower affinity (e.g., fentanyl) to displace it from the receptor. In the last decade, synthetic opioids, for example, fentanyl, its potent analogs such as carfentanil, and the benzimidazole derivative nitazene "superagonists" have contributed to the exponential growth in opioid deaths due to RD. The MOR, encoded by gene Oprm1, is widely expressed in the central and peripheral nervous systems, including centers that modulate breathing. Opioids bind to the receptors, but consensus is lacking on which site(s) makes the most significant contribution to the induction of OIRD. Both the preBötzinger complex (preBötC), the inspiratory rhythm generator, and the Kölliker-Fuse nucleus (KFN), the respiratory modulator, contribute to RD, but receptor binding is not restricted to a single site. Breathing is composed of three phases, inspiration, postinspiration, and active expiration, each generated by distinct rhythm-generating networks: the preBötC, the postinspiratory complex (PiCo), and the lateral parafacial nucleus (pFL), respectively. Somatostatin-expressing mouse cells involved in breathing regulation are not involved in opioid-induced RD.

Development and preclinical testing of a naloxone prodrug depot for extended protection against opioid overdose

The opioid crisis, driven by synthetic opioids like fentanyl, demands innovative solutions. The opioid antidote naloxone has a short action ( ~ 1 hour), requiring repeated doses. To address this, we present a new and simple naloxone prodrug delivery system repurposing a hydrophilic derivative of acoramidis, a potent transthyretin ligand. When the fully soluble prodrug solution is administered subcutaneously, the prodrug forms a zwitterionic depot at physiological pH, enabling extended naloxone release. This non-polymeric depot-forming approach is rare and employs carboxylesterase 2 for selective bioactivation, ensuring controlled drug release. In male rats and cynomolgus monkeys, a single subcutaneous dose provides steady naloxone release over several days, reducing blood-brain barrier diffusion, withdrawal symptoms, and CNS toxicity. Preclinical studies demonstrated efficacy in rat overdose models and achieved monkey naloxone levels matching effective human therapeutic levels. Although monkey efficacy was not assessed, combined rat efficacy and monkey pharmacokinetics suggest strong potential for successful human translation.

Pediatric Emergency Medical Services Activations Involving Naloxone Administration

Objectives: Fatal and nonfatal pediatric opioid poisonings have increased in recent years. Emergency medical services (EMS) clinicians are often the first to respond to an opioid poisoning and administer opioid reversal therapy. Currently, the epidemiology of prehospital naloxone use among children and adolescents is incompletely characterized. Thus, our study objective was to describe naloxone administrations reported by EMS clinicians during pediatric activations in the United States. Methods: We performed a cross-sectional study using the National Emergency Medical Services Information System (NEMSIS). Within NEMSIS, we identified emergency responses where children 1 day through 17 years old were documented by EMS to have received ≥1 dose of naloxone in 2022. We analyzed demographic and EMS characteristics and age-specific prevalence rates of activations where naloxone was reported. Results: In 2022, 6,215 activations involved naloxone administration to children. Most activations involved males (55.4%, 3,435 of 6,201) and occurred in urban settings (85.7%, 5,214 of 6,083). Naloxone administration prevalence per 10,000 activations was highest among the 13-17 year age group (57.5), followed by the 1 day to <1 year (17.9) age group. A dispatch complaint of an overdose or poisoning was documented in 28.9% (1,797 of 6,215) of activations and was more common among activations involving adolescents aged 13-17 years (31.5%, 1,555 of 4,937) than infants 1 day to <1 year (12.8%, 48 of 375). The first naloxone dose was documented to improve clinical status in 54.1% (3,136 of 5,793) of activations. Naloxone was documented to worsen clinical status in only 0.2% (11 of 5,793) of activations. Conclusions: In pediatric activations involving naloxone, less than one-third were dispatched as an overdose or poisoning but over half were documented to clinically improve after the first dose of naloxone. Naloxone was rarely documented to worsen clinical status. Our findings highlight the safety of prehospital naloxone use, as well as the importance of a high index of suspicion for opioid poisoning in the pediatric population. Opportunities exist to leverage linked data sources to develop interventions to improve prehospital opioid poisoning recognition and management.

Challenges with current diagnosis and treatment strategies for precipitated opioid withdrawal in the emergency department and the role of the pharmacist

PURPOSE

To demonstrate the challenges with current diagnosis and treatment strategies for precipitated opioid withdrawal secondary to naloxone the emergency department (ED) setting and describe the role of the emergency medicine (EM) pharmacist in its management.

SUMMARY

There are no standardized criteria to define precipitated opioid withdrawal syndrome, so the diagnosis is typically based on sentinel signs and symptoms and time course. Complicating factors include a positive urine toxicology screen for nonopioid substances, comorbidities and associated medications prior to admission, medications given in the ED, and a fluctuating patient course during the ED stay that likely involves all these issues. Although buprenorphine is frequently recommended as the primary treatment for precipitated withdrawal, its use can be complicated if patients are on methadone maintenance or other long-acting opioids. The EM pharmacist plays a key role in managing patients with precipitated withdrawal.

CONCLUSION

Practice changes related to the diagnosis and treatment of opioid use disorder (OUD) with precipitated withdrawal in the ED are needed. EM pharmacists as part of the interprofessional care team have an important role in the management of patients with OUD, including those patients undergoing possible precipitated withdrawal.

2024 American Heart Association and American Red Cross Guidelines for First Aid

Codeveloped by the American Heart Association and the American Red Cross, these guidelines represent the first comprehensive update of first aid treatment recommendations since 2010. Incorporating the results of structured evidence reviews from the International Liaison Committee on Resuscitation, these guidelines cover first aid treatment for critical and common medical, traumatic, environmental, and toxicological conditions. This update emphasizes the continuous evolution of evidence evaluation and the necessity of adapting educational strategies to local needs and diverse community demographics. Existing guidelines remain relevant unless specifically updated in this publication. Key topics that are new, are substantially revised, or have significant new literature include opioid overdose, bleeding control, open chest wounds, spinal motion restriction, hypothermia, frostbite, presyncope, anaphylaxis, snakebite, oxygen administration, and the use of pulse oximetry in first aid, with the inclusion of pediatric-specific guidance as warranted.

Identification and Health Risks of an Emerging Means of Drug Use in Correctional Facilities

Importance

Recreational use of drug-soaked paper strips (hereafter, strips) in correctional facilities poses a major public health risk owing to the diverse and potentially severe toxic effects of the substances they contain. Understanding the clinical manifestations and outcomes of exposure to these strips is important for developing effective management and prevention strategies.

Objective

To characterize the clinical manifestations, management, and outcomes of intoxication from strips in a correctional facility population, and to identify the specific substances present in these strips.

Design, Setting, and Participants

This is a case series with a retrospective medical record review and biospecimen analysis. Participants were incarcerated individuals from a county jail who presented to the emergency department of an urban hospital in Atlanta, Georgia, with suspected strip exposure between August 1, 2022, and November 1, 2023. Strip samples were tested using gas chromatography-mass spectrometry and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), and serum samples were analyzed via LC-QTOF-MS.

Exposures

All patients had suspected exposure to strips, thought to contain opioids, synthetic cannabinoid receptor agonists (SCRAs), and other novel synthetic drugs.

Main Outcomes and Measures

The primary outcomes were clinical manifestations of strip exposure, including clinical signs and symptoms, vital sign derangements, laboratory and imaging findings, treatments administered, and patient outcomes.

Results

There were 18 patients (all male; median [IQR] age, 27.5 [18.0-45.0] years) in total. Bradycardia (11 patients [61%]) and central nervous system depression (17 patients [94%]) were the most common clinical findings. Other symptoms included agitation (6 patients [33%]) and seizures (4 patients [22%]). Treatment primarily involved supportive care, with 2 patients requiring intubation. One patient died as a result of hypoxic ischemic encephalopathy. Analysis of strip samples revealed the presence of synthetic cannabinoids and benzimidazole opioids, but no household cleaners or pesticides. Serum testing confirmed the presence of SCRAs and their metabolites.

Conclusions and Relevance

In this case series study of strip intoxication among incarcerated individuals, severe and variable clinical manifestations were observed, predominantly associated with their SCRA content. Bradycardia in the context of major central nervous system depression was an indicator of severe SCRA toxic effects. Further research is needed to better understand strip use and to develop effective prevention and treatment strategies.

Diagnostic Approach to the Patient with Altered Mental Status

Acute encephalopathy is a common presenting symptom in the emergency room and complicates many hospital and intensive care unit admissions. The evaluation of patients with encephalopathy poses several challenges: limited history and examination due to the patient's mental status, broad differential diagnosis of systemic and neurologic etiologies, low yield of neurodiagnostic testing due to the high base rate of systemic causes, and the importance of identifying less common neurologic causes of encephalopathy that can be life-threatening if not identified and treated. This article discusses the differential diagnosis of acute encephalopathy, presents an approach to the history and examination in a patient with encephalopathy, reviews the literature on the yield of neurodiagnostic testing in this population, and provides a diagnostic framework for the evaluation of patients with altered mental status.

An autonomous implantable device for the prevention of death from opioid overdose

Opioid overdose accounts for nearly 75,000 deaths per year in the United States, now a leading cause of mortality among young people aged 18 to 45 years. At overdose levels, opioid-induced respiratory depression becomes fatal without the administration of naloxone within minutes. Currently, overdose survival relies on bystander intervention, requiring a nearby person to find the overdosed individual and have immediate access to naloxone to administer. To circumvent the bystander requirement, we developed the Naloximeter: a class of life-saving implantable devices that autonomously detect and treat overdose while simultaneously contacting first responders. We present three Naloximeter platforms, for fundamental research and clinical translation, all equipped with optical sensors, drug delivery mechanisms, and a supporting ecosystem of technology to counteract opioid-induced respiratory depression. In small and large animal studies, the Naloximeter rescues from otherwise fatal opioid overdose within minutes. This work introduces life-changing, clinically translatable technologies that can broadly benefit a susceptible population recovering from opioid use disorder.

An implantable system for opioid safety

Naloxone can effectively rescue victims from opioid overdose, but less than 5% survive due to delayed or absent first responder intervention. Current overdose reversal systems face key limitations, including low user adherence, false positive detection, and slow antidote delivery. Here, we describe a subcutaneously implanted robotic first responder to overcome these challenges. This implantable system for opioid safety continuously monitors vital signs, detecting opioid overdose through an algorithm analyzing the interplay of cardiorespiratory responses. To address battery concerns with continuous monitoring and multi-sensing modality, an adaptive algorithm dynamically adjusts sensor resolution, reducing the need for frequent charging. Furthermore, the implant includes an ultra-rapid naloxone delivery pump, delivering the 10-mg antidote within 10 s. In animal trials, the robotic first responder successfully revived 96% of overdosed pigs (n = 25) within 3.2 min, showcasing its potential to dramatically improve survival rates and combat the opioid epidemic.

Total-body imaging of mu-opioid receptors with [11C]carfentanil in non-human primates

PURPOSE

Mu-opioid receptors (MORs) are widely expressed in the central nervous system (CNS), peripheral organs, and immune system. This study measured the whole body distribution of MORs in rhesus macaques using the MOR selective radioligand [11C]carfentanil ([11C]CFN) on the PennPET Explorer. Both baseline and blocking studies were conducted using either naloxone or GSK1521498 to measure the effect of the antagonists on MOR binding in both CNS and peripheral organs.

METHODS

The PennPET Explorer was used for MOR total-body PET imaging in four rhesus macaques using [11C]CFN under baseline, naloxone pretreatment, and naloxone or GSK1521498 displacement conditions. Logan distribution volume ratio (DVR) was calculated by using a reference model to quantitate brain regions, and the standard uptake value ratios (SUVRs) were calculated for peripheral organs. The percent receptor occupancy (%RO) was calculated to establish the blocking effect of 0.14 mg/kg naloxone or GSK1521498.

RESULTS

The %RO in MOR-abundant brain regions was 75-90% for naloxone and 72-84% for GSK1521498 in blocking studies. A higher than 90% of %RO were observed in cervical spinal cord for both naloxone and GSK1521498. It took approximately 4-6 min for naloxone or GSK1521498 to distribute to CNS and displace [11C]CFN from the MOR. A smaller effect was observed in heart wall in the naloxone and GSK1521498 blocking studies.

CONCLUSION

[11C]CFN total-body PET scans could be a useful approach for studying mechanism of action of MOR drugs used in the treatment of acute and chronic opioid use disorder and their effect on the biodistribution of synthetic opioids such as CFN. GSK1521498 could be a potential naloxone alternative to reverse opioid overdose.

Synthetic opioids have disrupted conventional wisdom for treating opioid overdose

More than 90 % of opioid overdose deaths in North America are now caused by synthetic opioids, and while they are not as prevalent in the European illicit drug market, there are indications that they may become so in the near future. Multiple publications have argued that neither higher doses of naloxone nor more potent opioid receptor antagonists are needed to reverse a synthetic opioid overdose. However, the unique physicochemical properties of synthetic opioids result in a very rapid onset of respiratory depression compared to opium-based molecules, reducing the margin of opportunity to reverse an overdose. While intravenous administration rapidly delivers the high naloxone concentrations needed to reverse a synthetic opioid overdose, this option is often unavailable to first responders. A translational mechanistic model of opioid overdose developed by the FDA's Division of Applied Regulatory Science provides an unbiased approach to evaluate the effectiveness of overdose reversal strategies. Reports using this model demonstrated the naloxone tools (2 mg intramuscular and 4 mg intranasal) used by many first responders can result in an unacceptable loss of life following a synthetic opioid (fentanyl, carfentanil) overdose. Moreover, sequential (2.5 minutes between doses) administration of up to four doses of intranasal naloxone was no more effective at reducing the incidence of cardiac arrest (a surrogate endpoint for lethality) than a single dose, suggesting that attempts at titration may not provide the rapid absorption required to reverse a synthetic opioid overdose. This model was also used to compare the effectiveness of intranasal naloxone to intranasal nalmefene, a recently FDA-approved opioid receptor antagonist with a more rapid absorption and a higher affinity at mu-opioid receptors compared to intranasal naloxone. Intranasal nalmefene resulted in large and clinically meaningful reductions in the incidence of cardiac arrest compared to intranasal naloxone. Furthermore, simultaneous administration of four doses of intranasal naloxone was needed to reduce the incidence of cardiac arrest to levels approaching those produced by a single dose of intranasal nalmefene. These data are consistent with evidence that synthetics have indeed disrupted conventional wisdom in the treatment of opioid overdose.

Heroin-induced leukoencephalopathy: Chasing the imaging findings

We present a case of a 29-year-old male who was brought into the hospital due to unresponsiveness and found to have heroin inhalational leukoencephalopathy (HLE). HLE is one component of a broad spectrum of opioid encephalopathies that is associated with heroin inhalation and other opioids. There is considerable overlap of HLE with other toxic and hypoxic-ischemic encephalopathies; however, the specific territories of brain involvement help distinguish it from other cerebral insults. The goal of this study is to help elucidate the findings of HLE and compare these findings to other toxic and hypoxic-ischemic encephalopathies.

A Case Report of Delayed Opioid Toxidrome After Administration of Naloxone

Introduction

Opioid use is an epidemic that plagues the United States. Patients frequently present to the emergency department (ED) after opioid toxicity, which can lead to respiratory failure, apnea, and death. Although there is an effective antidote, naloxone, the current guidelines surrounding post-naloxone administration monitoring are loosely defined.

Case Report

We present a case in which an individual was administered naloxone after an intentional opioid overdose and was monitored for four hours, as is standard in our institution. He remained in the ED for additional workup following this observation period and subsequently experienced signs of severe respiratory depression, requiring bag-valve-mask ventilation, naloxone, and admission. Had he been discharged, as is typical after a four-hour observation period, the consequences could have been fatal. We present multiple theories as to why his opioid toxidrome may have presented in a delayed manner, including ingestion of fentanyl analogues and variability in metabolization of both opioids and naloxone. We also explore alternative overdose antidote products approved by the US Food and Drug Administration, which may impact post overdose care.

Conclusion

This case suggests that the correct amount of time to monitor patients after naloxone administration may be longer than originally thought. Our aim in this article was to further the discussion regarding the most appropriate observation period in cases of opioid toxicity.

An Autonomous Implantable Device for the Prevention of Death from Opioid Overdose

Opioid overdose accounts for nearly 75,000 deaths per year in the United States, representing a leading cause of mortality amongst the prime working age population (25-54 years). At overdose levels, opioid-induced respiratory depression becomes fatal without timely administration of the rescue drug naloxone. Currently, overdose survival relies entirely on bystander intervention, requiring a nearby person to discover and identify the overdosed individual, and have immediate access to naloxone to administer. Government efforts have focused on providing naloxone in abundance but do not address the equally critical component for overdose rescue: a willing and informed bystander. To address this unmet need, we developed the Naloximeter: a class of life-saving implantable devices that autonomously detect and treat overdose, with the ability to simultaneously contact first-responders. We present three Naloximeter platforms, for both fundamental research and clinical translation, all equipped with optical sensors, drug delivery mechanisms, and a supporting ecosystem of technology to counteract opioid-induced respiratory depression. In small and large animal studies, the Naloximeter rescues from otherwise fatal opioid overdose within minutes. This work introduces life-changing, clinically translatable technologies that broadly benefit a susceptible population recovering from opioid use disorder.

Implementing a text-message-based intervention to increase access to naloxone for patients on chronic opioid therapy

OBJECTIVE

To implement a text-message-based intervention for primary care patients taking chronic opioid therapy to increase access to naloxone.

DESIGN

Retrospective analysis of a hospital quality improvement initiative.

SETTING

This study was conducted with selected primary care practices affiliated with an academic medical center between March and July 2022.

PARTICIPANTS

Patients were eligible for receiving the intervention if they had chronic (≥90 days) opioid use of ≥50 morphine milligram equivalents/day and had not previously opted out of receiving text messages.

INTERVENTIONS

Text messages were sent to patients inquiring about interest in obtaining a naloxone kit, which prompted a pharmacist to contact the patient and provide the medication by mail.

MAIN OUTCOME MEASURES

We examined response rates to text messages and numbers of naloxone kits dispensed.

RESULTS

There were 243 patients identified who were sent the text message. Of these, 230 (94.7 percent) had a primary language of English, 150 (61.7 percent) were White, and 57 (23.5 percent) were Black/African American. The mean age was 57.3 years. After receiving the text messages, 64 (26.3 percent) of the 243 patients responded with "unsubscribe." Thirty-five (14.4 percent) patients responded to the message, and 18 patients (51.4 percent of those who responded or 7.4 percent of all included patients) wanted the medication and were contacted by a pharmacist who filled and mailed the prescription to them.

CONCLUSIONS

A text-message-based program to provide naloxone to patients with chronic opioid use was feasible. However, fewer than 15 percent of patients responded to the message, and just half of those wanted the medicine.

Reversal of Opioid-Induced Respiratory Depression in Healthy Volunteers: Comparison of Intranasal Nalmefene and Intranasal Naloxone

An open-label, randomized, crossover study in healthy volunteers compared the reversal of remifentanil-induced respiratory depression by intranasal (IN) naloxone hydrochloride (4 mg) to IN nalmefene (2.7 mg) (NCT04828005). Subjects were administered a hypercapnic gas mixture which produces an elevation in minute ventilation (MV), a result of the ventilatory response to hypercapnia. Subjects breathed a hypercapnic gas mixture through a tight-fitting mask for an initial period of 46 min prior to a series of mask "holidays" introduced to reduce subject discomfort and encourage study completion. Ten minutes after initiating the hypercapnic gas mixture, a remifentanil bolus was administered, and an infusion continued for the study duration. Subjects were administered either naloxone or nalmefene 15 min after initiating the remifentanil infusion and MV monitored for 21 min followed by a mask holiday. Both nalmefene and naloxone produced a time-dependent reversal of remifentanil-induced reductions in MV measured 2.5-20 min post administration. At the primary endpoint (5 min post administration), nalmefene increases in MV (5.75 L/min) were nearly twice that produced by naloxone (3.01 L/min) (P < .0009); the point estimate favors nalmefene, demonstrating non-inferiority and superiority. In this model of opioid-induced respiratory depression, nalmefene has a more rapid onset of action than naloxone, which required 20 min to achieve a comparable reversal of respiratory depression. Both nalmefene and naloxone were well tolerated by healthy volunteers. This rapid onset of action may prove particularly valuable in an era when over 90% of fatalities are linked to synthetic opioid overdose.

Comparison of intranasal naloxone and intranasal nalmefene in a translational model assessing the impact of synthetic opioid overdose on respiratory depression and cardiac arrest

Introduction

Using a validated translational model that quantitatively predicts opioid-induced respiratory depression and cardiac arrest, we compared cardiac arrest events caused by synthetic opioids (fentanyl, carfentanil) following rescue by intranasal (IN) administration of the μ-opioid receptor antagonists naloxone and nalmefene.

Methods

This translational model was originally developed by Mann et al. (Clin Pharmacol Ther 2022) to evaluate the effectiveness of intramuscular (IM) naloxone. We initially implemented this model using published codes, reproducing the effects reported by Mann et al. on the incidence of cardiac arrest events following intravenous doses of fentanyl and carfentanil as well as the reduction in cardiac arrest events following a standard 2 mg IM dose of naloxone. We then expanded the model in terms of pharmacokinetic and µ-opioid receptor binding parameters to simulate effects of 4 mg naloxone hydrochloride IN and 3 mg nalmefene hydrochloride IN, both FDA-approved for the treatment of opioid overdose. Model simulations were conducted to quantify the percentage of cardiac arrest in 2000 virtual patients in both the presence and absence of IN antagonist treatment.

Results

Following simulated overdoses with both fentanyl and carfentanil in chronic opioid users, IN nalmefene produced a substantially greater reduction in the incidence of cardiac arrest compared to IN naloxone. For example, following a dose of fentanyl (1.63 mg) producing cardiac arrest in 52.1% (95% confidence interval, 47.3-56.8) of simulated patients, IN nalmefene reduced this rate to 2.2% (1.0-3.8) compared to 19.2% (15.5-23.3) for IN naloxone. Nalmefene also produced large and clinically meaningful reductions in the incidence of cardiac arrests in opioid naïve subjects. Across dosing scenarios, simultaneous administration of four doses of IN naloxone were needed to reduce the percentage of cardiac arrest events to levels that approached those produced by a single dose of IN nalmefene.

Conclusion

Simulations using this validated translational model of opioid overdose demonstrate that a single dose of IN nalmefene produces clinically meaningful reductions in the incidence of cardiac arrest compared to IN naloxone following a synthetic opioid overdose. These findings are especially impactful in an era when >90% of all opioid overdose deaths are linked to synthetic opioids such as fentanyl.

Case of pediatric cerebellar, hippocampal, and basal nuclei transient edema with restricted diffusion (CHANTER) syndrome in a 2-year-old girl

Cerebellar, hippocampal, and basal nuclei transient edema with restricted diffusion (CHANTER) syndrome is a recently described entity that refers to a specific pattern of cerebellar edema with restricted diffusion and crowding of the fourth ventricle among other findings. The syndrome is commonly associated with toxic opioid exposure. While most commonly seen in adults, we present a case of a 2-year-old girl who survived characteristic history and imaging findings of CHANTER syndrome.

Clinical Pharmacokinetics and Pharmacodynamics of Naloxone

Naloxone is a World Health Organization (WHO)-listed essential medicine and is the first choice for treating the respiratory depression of opioids, also by lay-people witnessing an opioid overdose. Naloxone acts by competitive displacement of opioid agonists at the μ-opioid receptor (MOR). Its effect depends on pharmacological characteristics of the opioid agonist, such as dissociation rate from the MOR receptor and constitution of the victim. Aim of treatment is a balancing act between restoration of respiration (not consciousness) and avoidance of withdrawal, achieved by titration to response after initial doses of 0.4-2 mg. Naloxone is rapidly eliminated [half-life (t1/2) 60-120 min] due to high clearance. Metabolites are inactive. Major routes for administration are intravenous, intramuscular, and intranasal, the latter primarily for take-home naloxone. Nasal bioavailability is about 50%. Nasal uptake [mean time to maximum concentration (Tmax) 15-30 min] is likely slower than intramuscular, as reversal of respiration lag behind intramuscular naloxone in overdose victims. The intraindividual, interindividual and between-study variability in pharmacokinetics in volunteers are large. Variability in the target population is unknown. The duration of action of 1 mg intravenous (IV) is 2 h, possibly longer by intramuscular and intranasal administration. Initial parenteral doses of 0.4-0.8 mg are usually sufficient to restore breathing after heroin overdose. Fentanyl overdoses likely require higher doses of naloxone. Controlled clinical trials are feasible in opioid overdose but are absent in cohorts with synthetic opioids. Modeling studies provide valuable insight in pharmacotherapy but cannot replace clinical trials. Laypeople should always have access to at least two dose kits for their interim intervention.

A Wearable Device Towards Automatic Detection and Treatment of Opioid Overdose

Opioid-induced overdose is one of the leading causes of death among the US population under the age of 50. In 2021 alone, the death toll among opioid users rose to a devastating number of over 80,000. The overdose process can be reversed by the administration of naloxone, an opioid antagonist that rapidly counteracts the effects of opioid-induced respiratory depression. The idea of a closed-loop opioid overdose detection and naloxone delivery has emerged as a potential engineered solution to mitigate the deadly effects of the opioid epidemic. In this work, we introduce a wrist-worn wearable device that overcomes the portability issues of our previous work to create a closed-loop drug-delivery system, which includes (1) a Near-Infrared Spectroscopy (NIRS) sensor to detect a hypoxia-driven opioid overdose event, (2) a MOSFET switch, and (3) a Zero-Voltage Switching (ZVS) electromagnetic heater. Using brachial artery occlusion (BAO) with human subjects (n = 8), we demonstrated consistent low oxygenation events. Furthermore, we proved our device's capability to release the drug within 10 s after detecting a hypoxic event. We found that the changes in the oxyhemoglobin, deoxyhemoglobin and oxygenation saturation levels ( SpO2) were different before and after the low-oxygenation events ( 0.001). Although additional human experiments are needed, our results to date point towards a potential tool in the battle to mitigate the effects of the opioid epidemic.

Psychostimulant drug co-ingestion in non-fatal opioid overdose

Introduction

In 2019, there were over 16,000 deaths from psychostimulant overdose with 53.5% also involving an opioid. Given the substantial mortality stemming from opioid and psychostimulant co-exposure, evaluation of clinical management in this population is critical but remains understudied. This study aims to characterize and compare clinical management and outcomes in emergency department (ED) overdose patients with analytically confirmed exposure to both opioids and psychostimulants with those exposed to opioids alone.

Methods

This was a secondary analysis of a prospective consecutive cohort of ED patients age 18+ with opioid overdose at 9 hospital sites from September 21, 2020 to August 17, 2021. Toxicologic analysis was performed using liquid chromatography quadrupole time-of-flight mass spectrometry. Patients were divided into opioid-only (OO) and opioid plus psychostimulants (OS) groups. The primary outcome was total naloxone bolus dose administered. Secondary outcomes included endotracheal intubation, cardiac arrest, troponin elevation, and abnormal presenting vital signs. We employed t-tests, chi-squared analyses and multivariable regression models to compare outcomes between OO and OS groups.

Results

Of 378 enrollees with confirmed opioid overdose, 207 (54.8%) had psychostimulants present. OO patients were significantly older (mean 45.2 versus 40.6 years, p < 0.01). OS patients had significantly higher total naloxone requirements (mean total dose 2.79 mg versus 2.12 mg, p = 0.009). There were no significant differences in secondary outcomes.

Conclusion

Approximately half of ED patients with confirmed opioid exposures were also positive for psychostimulants. Patients in the OS group required significantly higher naloxone doses, suggesting potential greater overdose severity.

Feeling safer: effectiveness, feasibility, and acceptability of continuous pulse oximetry for people who smoke opioids at overdose prevention services in British Columbia, Canada

BACKGROUND

Smoking is the most common mode of unregulated opioid consumption overall and implicated in fatal overdoses in British Columbia (BC). In part, perception of decreased risk (e.g., fewer who smoke carry naloxone kits) and limited smoking-specific harm reduction services contribute to overdose deaths. Overdose prevention services (OPS) offer supervised settings for drug use. Continuous pulse oximetry, common in acute care, allows real-time, remote oxygen monitoring. We evaluated the effectiveness of a novel continuous pulse oximetry protocol aimed at allowing physical distancing (as required by COVID-19, secluded spaces, and to avoid staff exposure to vaporized opioids), its feasibility, and acceptability at OPS for people who smoke opioids.

METHODS

This was a mixed methods survey study. We developed a continuous pulse oximetry protocol in collaboration with clinical experts and people with lived/living experience of substance use. We implemented our protocol from March to August 2021 at four OPS in BC permitting smoking. We included adults (≥ 18 years) presenting to OPS to smoke opioids. Peer researchers collected demographic, health, and substance use information, and conducted structured observations. OPS clients participating in our study, OPS staff, and peer researchers completed post-monitoring surveys. We analyzed responses using a thematic inductive approach and validated themes with peer researchers.

RESULTS

We included 599 smoking events. OPS clients participating in our study had a mean age of 38.5 years; 73% were male. Most (98%) reported using "down", heroin, or fentanyl; 48% concurrently used other substances (32% of whom reported stimulants); 76% reported smoking alone in the last 3 days; and 36% reported an overdose while smoking. Respondents reported that the protocol facilitated physical distancing, was easy to use, high satisfaction, improved confidence, improved sense of safety, and that they would use it again.

CONCLUSIONS

Continuous pulse oximetry allowed safe physical distancing, was feasible, and acceptable in monitoring people who smoke opioids at OPS.

Intranasal Naloxone Repeat Dosing Strategies and Fentanyl Overdose: A Simulation-Based Randomized Clinical Trial

Importance

Questions have emerged as to whether standard intranasal naloxone dosing recommendations (ie, 1 dose with readministration every 2-3 minutes if needed) are adequate in the era of illicitly manufactured fentanyl and its derivatives (hereinafter, fentanyl).

Objective

To compare naloxone plasma concentrations between different intranasal naloxone repeat dosing strategies and to estimate their effect on fentanyl overdose.

Design, Setting, and Participants

This unblinded crossover randomized clinical trial was conducted with healthy participants in a clinical pharmacology unit (Spaulding Clinical Research, West Bend, Wisconsin) in March 2021. Inclusion criteria included age 18 to 55 years, nonsmoking status, and negative test results for the presence of alcohol or drugs of abuse. Data analysis was performed from October 2021 to May 2023.

Intervention

Naloxone administered as 1 dose (4 mg/0.1 mL) at 0, 2.5, 5, and 7.5 minutes (test), 2 doses at 0 and 2.5 minutes (test), and 1 dose at 0 and 2.5 minutes (reference).

Main Outcomes and Measures

The primary outcome was the first prespecified time with higher naloxone plasma concentration. The secondary outcome was estimated brain hypoxia time following simulated fentanyl overdoses using a physiologic pharmacokinetic-pharmacodynamic model. Naloxone concentrations were compared using paired tests at 3 prespecified times across the 3 groups, and simulation results were summarized using descriptive statistics.

Results

This study included 21 participants, and 18 (86%) completed the trial. The median participant age was 34 years (IQR, 27-50 years), and slightly more than half of participants were men (11 [52%]). Compared with 1 naloxone dose at 0 and 2.5 minutes, 1 dose at 0, 2.5, 5, and 7.5 minutes significantly increased naloxone plasma concentration at 10 minutes (7.95 vs 4.42 ng/mL; geometric mean ratio, 1.95 [1-sided 97.8% CI, 1.28-∞]), whereas 2 doses at 0 and 2.5 minutes significantly increased the plasma concentration at 4.5 minutes (2.24 vs 1.23 ng/mL; geometric mean ratio, 1.98 [1-sided 97.8% CI, 1.03-∞]). No drug-related serious adverse events were reported. The median brain hypoxia time after a simulated fentanyl 2.97-mg intravenous bolus was 4.5 minutes (IQR, 2.1-∞ minutes) with 1 naloxone dose at 0 and 2.5 minutes, 4.5 minutes (IQR, 2.1-∞ minutes) with 1 naloxone dose at 0, 2.5, 5, and 7.5 minutes, and 3.7 minutes (IQR, 1.5-∞ minutes) with 2 naloxone doses at 0 and 2.5 minutes.

Conclusions and Relevance

In this clinical trial with healthy participants, compared with 1 intranasal naloxone dose administered at 0 and 2.5 minutes, 1 dose at 0, 2.5, 5, and 7.5 minutes significantly increased naloxone plasma concentration at 10 minutes, whereas 2 doses at 0 and 2.5 minutes significantly increased naloxone plasma concentration at 4.5 minutes. Additional research is needed to determine optimal naloxone dosing in the community setting.

Trial Registration

ClinicalTrials.gov Identifier: NCT04764630.

Deciphering the Causality between Gut Microbiota Dysbiosis and Poisoning by Narcotics and Psychodysleptics: A Mendelian Randomization Analysis

BACKGROUND

This study investigates the connection between gut microbiota and poisoning caused by narcotics and psychodysleptics, using Mendelian randomization (MR) to explore possible causal relationships.

METHODS

The study employed the MR analysis, leveraging genetic variants as instrumental variables to facilitate robust causal inference. Data for gut microbiota was extracted from the MiBioGen study, integrating genome-wide genotyping data with 16S fecal microbiota profiles. Outcome metrics were based on the Finngen study. Genetic instruments were meticulously extracted based on stringent criteria, and harmonized with SNP outcomes associated with "Poisoning by narcotics and psychodysleptics (hallucinogens)". The inverse-variance weighted (IVW) method was utilized for MR analysis, supplemented by sensitivity analyses including MR-Egger Regression, Weighted Median Approach, and Leave-One-Out Cross-Validation.

RESULTS

Among various microbial groups, nine showed significant statistical links. Specifically, Class Negativicutes (OR 5.68, 95% CI 2.13-15.16, p = 0.0005) and Order Selenomonadales (OR 5.68, 95% CI 2.13-15.16, p = 0.0005) were notably associated. These findings were consistent across different sensitivity analyses.

CONCLUSION

The relationship between gut microbiota and the adverse effects of narcotics and psychodysleptics is an emerging area of research. Our MR study identifies certain microbes that might influence the body's response to these substances. These insights could help in predicting and treating the effects of narcotics and psychodysleptics in the future.

Opioid Misuse Harm Reduction

BACKGROUND/AIMS

The misuse of opioids by the public is a major health issue. Prescription opioids and nonprescription opioids, such as heroin and opium, are misused in epidemic proportions. When opioids are used incorrectly or illegally, they can lead to drug dependence, addiction, morbidity, and mortality. This program is in collaboration with the Jolt Foundation that provides resources to prevent opioid overdose deaths.

DESIGN/METHODS

This program involves community education on the dangers of opioid use and training on the use of naloxone rescue procedures to prevent overdose deaths. A pretest-posttest design was employed to determine if participants gained knowledge regarding the naloxone administration procedures.

PARTICIPANTS

The researcher presented 10 community naloxone trainings that included staff from 20 different social service agencies, two schools, and three local churches. Each agency received at least one naloxone kit.

FINDINGS

The outcomes were met and included educating 137 participants on the risk factors and signs and symptoms of opioid overdose and the proper procedure to administer naloxone. One hundred twenty-eight posttests were returned and showed that the objectives for the project were met. The overall mean score for the pretests was 65.00 ( n = 126) with a standard deviation of 19.01, and the overall mean for the posttests was 86.64 ( n = 128) with a standard deviation of 14.60.

CONCLUSIONS

Community social service agency staff were successfully educated to respond appropriately to overdose situations in a group training setting as evidenced by significant posttest scores.

Trends and correlates of naloxone possession and use among people who inject drugs in Seattle, Washington

BACKGROUND

Naloxone distribution has been implemented as an essential opioid overdose prevention measure for people who inject drugs (PWID), and many jurisdictions in the United States have implemented policy change to increase naloxone access. This project describes temporal trends in and correlates of naloxone possession and use among PWID in the Seattle area of Washington State.

METHODS

Using a repeat cross-sectional design, we utilized two sets of serial cross-sectional surveys of PWID, which included biennial surveys of Seattle area syringe service program (SSP) clients and community-based National HIV Behavioral Surveillance surveys of PWID (NHBS-PWID) conducted from 2012-2019. Survey participant characteristics were descriptively compared between participants reporting naloxone possession to those not reporting naloxone possession. Multivariable Poisson regression was used to calculate prevalence ratios for naloxone possession comparing later to earlier survey years, adjusting for age, gender, race/ethnicity, primary drug, and experiencing and witnessing an overdose in the past 12 months.

RESULTS

Naloxone possession and use increased in both survey populations. The prevalence of possessing naloxone was 2.8 times greater [2019 vs. 2013= 95% CI: 2.40-3.33] among SSP participants and 2.8 times greater [2018 vs. 2012=95% CI: 2.41-3.16] among NHBS-PWID participants for the most recent time period. The prevalence of naloxone use was 1.3 times greater [2019 vs. 2017= 95% CI: 1.13-1.58] and 2.1 times greater [2015 vs. 2012=95% CI:1.62-2.73] among SSP and NHBS-PWID participants, respectively, for the most recent time period.

CONCLUSION

Naloxone possession and use increased in PWID in the Seattle area from 2012-2019, and is, at least in part, likely the result of numerous policy and programmatic efforts to facilitate easier naloxone accessibility in the wake of dramatic increases in overdose mortality. Further research on disparities in naloxone possession are needed to ensure equitable access.

Association Between Naloxone Coprescription Mandates and Postoperative Outcomes

INTRODUCTION

The opioid epidemic is a public health issue in the United States. The objective of this study was to evaluate the association between naloxone coprescription mandates and postoperative outcomes.

BACKGROUND

Data on naloxone coprescription mandates show mixed evidence for fatal overdoses in the broader population. How these mandates have impacted surgical patients has not been fully explored.

METHODS

Healthcare claims data were used to identify all patients undergoing 1 of 50 common procedures between January 1, 2004, and June 30, 2019, and categorized as high risk for opioid overdose. The primary outcomes were an emergency department visit or hospital admission within 30 postoperative days. To reduce confounding, the association between this outcome and the implementation of naloxone coprescription mandates was estimated using a difference-in-differences approach.

RESULTS

The study included 429,878 surgical patients with an average age of 54.8 years (SD=15.9 years) and with 257,728 females (60.0%). There was no significant association between naloxone prescribing mandates and the primary outcomes. After adjustment for potential confounders, the incidence of hospital admission was 3.26% after implementation of a naloxone coprescription mandate compared with 3.33% before (difference change: -0.08%, 95% CI: -0.44% to 0.29%, P =0.68). The incidence of an emergency department visit was 7.06% after implementation of a naloxone coprescription mandate compared with 7.73% before (difference: -0.67%, 95% CI: -1.39% to 0.05%, P =0.07). These results were robust to a variety of sensitivity and subgroup analyses.

CONCLUSIONS

Naloxone coprescription mandates were not associated with a statistically or clinically significant change in emergency department visits or hospital admissions within 30 postoperative days.

Community pharmacists' naloxone counseling: A theory-informed qualitative study

BACKGROUND

Opioid-related overdose (ORO) deaths have reached a record high in the United States. Naloxone is an opioid antagonist that can rapidly reverse an opioid overdose. Pharmacists are in an ideal position to provide naloxone and related counseling, given their accessibility and expertise. However, minimal research is available on community pharmacists' naloxone counseling.

OBJECTIVES

The aim of this study was to investigate Georgia community pharmacists' naloxone counseling as well as explore their attitudes, subjective norms, and perceived behavioral control toward counseling.

METHODS

Semi-structured telephone interviews were conducted to elicit pharmacists' beliefs and practices regarding naloxone counseling. The interviews were guided by open-ended questions based on the theory of planned behavior (TPB). Thematic analysis was performed to identify the modal salient beliefs expressed by the pharmacists. The Consolidated Criteria for Reporting Qualitative Research was used to report the study findings.

RESULTS

A total of 12 community pharmacists participated. Pharmacists held mixed attitudes toward naloxone counseling. While they recognized it as a vital part of their profession to prevent ORO deaths, they also expressed concerns about offending patients. Regarding normative beliefs, pharmacists identified several groups, including regulatory agencies (e.g., Board of Pharmacy, CDC), managers, news/media, patients, and doctors, influencing their provision of naloxone counseling. Facilitators to counseling included receiving naloxone training and having access to counseling guidelines and resources. Reimbursement issues, high costs of naloxone, and lack of patient awareness were the most commonly cited barriers. Pharmacists reported participating in counseling and providing information on identifying signs of opioid overdose and administering naloxone.

CONCLUSIONS

The TPB is a useful framework for understanding community pharmacists' beliefs and practices regarding naloxone counseling. Capitalizing on facilitators and targeting barriers related to pharmacists' reimbursement issues, high costs of naloxone, and increasing patients' awareness of naloxone use and benefits may enhance pharmacists' naloxone counseling.

[Opioid overdose prevention and naloxone diffusion (POP program): Results of an overview conducted among addiction specialized centres]

INTRODUCTION

In France, opioids are responsible for the majority of overdose deaths in France. The antidote naloxone is available in France in take home formulations since 2016. Addiction specialized centres are in front-line for naloxone diffusion. The objective was to provide an overview of professional practices, difficulties and needs regarding overdose prevention and naloxone diffusion in these centres of the Provence-Alpes-Côte d'Azur (PACA) region.

METHODS

The POP programme "Prevention and harm reduction of opioid overdoses in PACA region" aims to improve the care of patients at risk of overdose and facilitate naloxone diffusion. The 75 addiction specialized centres of the PACA region were invited to respond to a semi-structured interview or a telephone questionnaire. Data collected included 2020 centres' activity and professionals' perceptions of overdose risk in their active file, their practices, difficulties and needs.

RESULTS

Overall, 33 centres answered. Among them, 22 were dispensing naloxone with a mean of 20 kits dispensed in 2020 (min-max: 1-100). Two strategies were pointed out: systematically offering of naloxone to all opioids users or targeting people considered at risk. Several difficulties limiting naloxone diffusion were expressed: a lack of knowledge from opioids users, refusal from people not feeling concerned or refusing the injectable formulation, a lack of training of some professionals to be comfortable with the tool or reglementary or time constraints.

CONCLUSION

Naloxone diffusion is incrementally getting into common practices. However barriers are persisting. On the basis of expressed difficulties and needs, information and training materials were co-designed and diffused.

Possible Delay in Symptomatology of a Methadone Overdose in a Patient Ingesting an Energy Drink and Dextroamphetamine/Amphetamine

Introduction: Methadone is a mu-opioid agonist with a delayed time to peak concentration that requires an extended period of monitoring following an overdose. Available data suggests that the combination of psychostimulants with methadone may augment antinociception and tolerance to opioids. Case Report: A 26-year-old male (83.9 kg) presented to the ED approximately 1 hour after unintentionally ingesting 200-250 mg of liquid methadone and an energy drink, along with 20 mg of dextroamphetamine/amphetamine prior to the event. Vital signs were: blood pressure (BP), 143/91 mmHg; heart rate (HR), 74; respirations (RR), 16; oxygen saturation 95% on room air. His urine drug screen was positive for amphetamines and methadone. Patient was monitored for 4 hours with no change in status and was discharged home. Approximately 26 hours later patient was found cyanotic and apneic. Patient was given 2 mg of naloxone and awoke with normal mental status. On presentation the patient's vital signs were: BP, 114/70 mmHg; HR, 114; RR 16; oxygen saturation 94% on 3 liters nasal cannula. During his ED stay, he required 2 doses of naloxone secondary to oxygen desaturation and was admitted to the hospital. His repeat urine drug screen was positive for amphetamines and methadone. The patient was discharged the following day. Discussion: This case illustrates an unintentional methadone overdose combined with the intentional ingestion of an energy drink and dextroamphetamine/amphetamine that possibly masked the toxicity for over 24 hrs. Monitoring parameters for methadone overdoses may need re-evaluation in the setting of the co-ingestion of a stimulant.

High-Dose Naloxone Formulations Are Not as Essential as We Thought

Naloxone is a U.S. Food and Drug Administration (FDA) approved opioid antagonist for reversing opioid overdoses. Naloxone is available to the public, and can be administered through intramuscular (IM), intravenous (IV), and intranasal spray (IN) routes. Our literature review aimed to improve understanding regarding the adequacy of the regularly distributed two doses of low-dose IM or IN naloxone in effectively reversing fentanyl overdoses and whether high-dose naloxone formulations (HDNF) formulations are an optimal solution to this problem. Moreover, our initiative incorporated the perspectives and experiences of people who use drugs (PWUD), enabling a more practical and contextually-grounded analysis. We began by discussing the knowledge and perspectives of Tennessee Harm Reduction, a small peer-led harm reduction organization. A comprehensive literature review was then conducted to gather relevant scholarly works on the subject matter. The evidence indicates that, although higher doses of naloxone have been administered in both clinical and community settings, the vast majority of fentanyl overdoses can be successfully reversed using standard IM dosages with the exception of carfentanil overdoses and other more potent fentanyl analogs, which necessitate three or more doses for effective reversal. Multiple studies documented the risk of precipitated withdrawal using high doses of naloxone. Notably, the possibility of recurring overdose symptoms after resuscitation exists, contingent upon the half-life of the specific opioid. Considering these findings and the current community practice of distributing multiple doses, we recommend providing at least four standard doses of IN or IM naloxone to each potential bystander, and training them to continue administration until the recipient achieves stability, ensuring appropriate intervals between each dose. Based on the evidence, we do not recommend HDNF in the place of providing four doses of standard naloxone due to the higher cost, risk of precipitated withdrawal and limited evidence compared to standard IN and IM. All results must be taken into consideration with the inclusion of the lived experiences, individual requirements, and consent of PWUD as crucial factors. It is imperative to refrain from formulating decisions concerning PWUD in their absence, as their participation and voices should be integral to the decision-making process.

Experiences Administering Naloxone Among People in Different Social Roles: People Who Use Opioids and Family Members and Friends

Unintentional drug overdose deaths continue to be a critical public health issue. Naloxone, a nonscheduled, safe, and effective drug that reverses opioid-involved overdoses is available to non-medically trained individuals ("lay people"), but there is scant information about how people in different social roles experience naloxone administration. We conducted 24 in-depth interviews with people who use opioids (PWUO; n = 15) and family members and friends of people who use opioids (FF; n = 9) who had administered naloxone in response to an opioid overdose. Compared with PWUO, members of the FF group were less reticent to administer naloxone in response to an overdose. PWUO and FF had different perspectives of law enforcement and demonstrated varied knowledge of the Good Samaritan Law. While PWUO found that having and administering naloxone was empowering, FF took a more pragmatic approach, reporting the need for naloxone as an unfortunate reality of their loved one's drug use.

The Opioid Overdose Resuscitation Education for Addiction Counselors and Trainees (Opioid Overdose REACT) naloxone response education pilot project improved confidence and knowledge among addiction counselors and trainees

INTRODUCTION

Community programs to teach nonmedical laypeople how to recognize an opioid overdose and effectively resuscitate the victim using naloxone have proliferated recently as a significant component of harm-reduction efforts. Although many such programs target laypeople like first responders or friends and family members of people who use drugs, there are currently no programs that specifically target addiction counselors, despite their work with a client population at high risk of an opioid overdose.

METHODS

The four-hour curriculum designed by the authors covered opioid agonist and antagonist pharmacology; opioid toxidrome signs; legal implications and indications for using the naloxone kits; and hands-on training. Participants were two cohorts of addiction counselors and addiction counseling trainees at our institution and an affiliated Opioid Treatment Program methadone clinic. Surveys testing participant knowledge and confidence were conducted at baseline, immediately post-training, six months post-training, and 12 months post-training.

RESULTS

Overall, opioid and naloxone pharmacology knowledge, as well as the confidence to intervene in an overdose emergency, improved among participants in both cohorts. Knowledge scores at baseline (n = 36, median 5/10) improved significantly immediately post-training (n = 31, median 7/10, P < 0.0001, Wilcoxon signed-rank test) and were sustained six (n = 19) and 12 months (n = 11) later. Two participants reported using their naloxone kits to successfully reverse a client overdose in the 12 months after taking the course.

DISCUSSION

These results from our knowledge translation pilot project suggest that our educational program to train addiction counselors in opioid pharmacology and toxicology, allowing them to recognize and respond to an opioid overdose, is feasible and could be effective. Specific barriers to implementing such educational programs include cost, stigma, and unclear best practice for designing and conducting these programs.

CONCLUSIONS

Further study of providing opioid pharmacology education and overdose and naloxone training to addiction counselors and counseling trainees appears to be warranted.

Comparison of rhabdomyolysis in acutely intoxicated patients with psychotropic and chemical substances

INTRODUCTION

Rhabdomyolysis is characterized by a muscle injury that leads to the release of intracellular muscle contents/constituents into the systemic circulation.

A pharmacologically pre-contracted smooth muscle bowel model for the study of highly-potent opioid receptor agonists and antagonists

Isolated organ models are a versatile tool for pharmacological and toxicological research. Small bowel has been used to assess the inhibition of smooth muscle contraction by opioids. In the present study, we set out to establish a pharmacologically stimulated rat bowel model. The effects of carfentanil, remifentanil and the new synthetic opioid U-48800 and their respective antagonists naloxone, nalmefene and naltrexone were studied in a small bowel model in rats. The IC₅₀ values of the tested opioids were as follows: carfentanil (IC₅₀ = 0.02 µmol/L, CI 0.02-0.03 µmol/L) ≫ remifentanil (IC₅₀ = 0.51 µmol/L, CI 0.40-0.66 µmol/L) ≫ U-48800 (IC₅₀ = 1.36 µmol/L, CI 1.20-1.54 µmol/L). The administration of the opioid receptor antagonists naloxone, naltrexone and nalmefene led to progressive, parallel rightward shifts of the dose-response curves. Naltrexone was most potent in antagonizing the effects of U-48800, whereas naltrexone and nalmefene were most effective in antagonizing the effects of carfentanil. In summary, the current model seems to be a robust tool to study opioid effects in a small bowel model without the necessity of using electrical stimulation.

The human neurosecretome: extracellular vesicles and particles (EVPs) of the brain for intercellular communication, therapy, and liquid-biopsy applications

Emerging evidence suggests that brain derived extracellular vesicles (EVs) and particles (EPs) can cross blood-brain barrier and mediate communication among neurons, astrocytes, microglial, and other cells of the central nervous system (CNS). Yet, a complete understanding of the molecular landscape and function of circulating EVs & EPs (EVPs) remain a major gap in knowledge. This is mainly due to the lack of technologies to isolate and separate all EVPs of heterogeneous dimensions and low buoyant density. In this review, we aim to provide a comprehensive understanding of the neurosecretome, including the extracellular vesicles that carry the molecular signature of the brain in both its microenvironment and the systemic circulation. We discuss the biogenesis of EVPs, their function, cell-to-cell communication, past and emerging isolation technologies, therapeutics, and liquid-biopsy applications. It is important to highlight that the landscape of EVPs is in a constant state of evolution; hence, we not only discuss the past literature and current landscape of the EVPs, but we also speculate as to how novel EVPs may contribute to the etiology of addiction, depression, psychiatric, neurodegenerative diseases, and aid in the real time monitoring of the "living brain". Overall, the neurosecretome is a concept we introduce here to embody the compendium of circulating particles of the brain for their function and disease pathogenesis. Finally, for the purpose of inclusion of all extracellular particles, we have used the term EVPs as defined by the International Society of Extracellular Vesicles (ISEV).

Catalytic Antibody Blunts Carfentanil-Induced Respiratory Depression

Carfentanil, the most potent of the fentanyl analogues, is at the forefront of synthetic opioid-related deaths, second to fentanyl. Moreover, the administration of the opioid receptor antagonist naloxone has proven inadequate for an increasing number of opioid-related conditions, often requiring higher/additional doses to be effective, as such interest in alternative strategies to combat more potent synthetic opioids has intensified. Increasing drug metabolism would be one strategy to detoxify carfentanil; however, carfentanil's major metabolic pathways involve N-dealkylation or monohydroxylation, which do not lend themselves readily to exogenous enzyme addition. Herein, we report, to our knowledge, the first demonstration that carfentanil's methyl ester when hydrolyzed to its acid was found to be 40,000 times less potent than carfentanil in activating the μ-opioid receptor. Physiological consequences of carfentanil and its acid were also examined through plethysmography, and carfentanil's acid was found to be incapable of inducing respiratory depression. Based upon this information, a hapten was chemically synthesized and immunized, allowing the generation of antibodies that were screened for carfentanil ester hydrolysis. From the screening campaign, three antibodies were found to accelerate the hydrolysis of carfentanil's methyl ester. From this series of catalytic antibodies, the most active underwent extensive kinetic analysis, allowing us to postulate its mechanism of hydrolysis against this synthetic opioid. In the context of potential clinical applications, the antibody, when passively administered, was able to reduce respiratory depression induced by carfentanil. The data presented supports further development of antibody catalysis as a biologic strategy to complement carfentanil overdose reversal.

Public health and medical preparedness for mass casualties from the deliberate release of synthetic opioids

The large amounts of opioids and the emergence of increasingly potent illicitly manufactured synthetic opioids circulating in the unregulated drug supply in North America and Europe are fueling not only the ongoing public health crisis of overdose deaths but also raise the risk of another type of disaster: deliberate opioid release with the intention to cause mass harm. Synthetic opioids are highly potent, rapidly acting, can cause fatal ventilatory depression, are widely available, and have the potential to be disseminated for mass exposure, for example, if effectively formulated, via inhalation or ingestion. As in many other chemical incidents, the health consequences of a deliberate release of synthetic opioid would manifest quickly, within minutes. Such an incident is unlikely, but the consequences could be grave. Awareness of the risk of this type of incident and preparedness to respond are required to save lives and reduce illness. Coordinated planning across the entire local community emergency response system is also critical. The ability to rapidly recognize the opioid toxidrome, education on personal protective actions, and training in medical management of individuals experiencing an opioid overdose are key components of preparedness for an opioid mass casualty incident.

"It's just another tool on my toolbelt": New York state law enforcement officer experiences administering naloxone

BACKGROUND

Although naloxone is widely acknowledged as a life-saving intervention and a critical tool for first responders, there remains a need to explore how law enforcement officers have adapted to a shifting scope of work. Past research has focused mainly on officer training, their abilities to administer naloxone, and to a lesser extent on their experiences and interactions working with people who use drugs (PWUD).

METHODS

A qualitative approach was used to explore officer perspectives and behaviors surrounding responses to incidents of suspected opioid overdose. Between the months of March and September 2017, semi-structured interviews were conducted with 38 officers from 17 counties across New York state (NYS).

RESULTS

Analysis of in-depth interviews revealed that officers generally considered the additional responsibility of administering naloxone to have become "part of the job". Many officers reported feeling as though they are expected to wear multiple hats, functioning as both law enforcement and medical personnel and at times juggling contradictory roles. Evolving views on drugs and drug use defined many interviews, as well as the recognition that a punitive approach to working with PWUD is not the solution, emphasizing the need for cohesive, community-wide support strategies. Notable differences in attitudes toward PWUD appeared to be influenced by an officer's connection to someone who uses drugs and/or due to a background in emergency medical services.

CONCLUSION

Law enforcement officers in NYS are emerging as an integral part of the continuum of care for PWUD. Our findings are capturing a time of transition as more traditional approaches to law enforcement appear to be shifting toward those prioritizing prevention and diversion. Widespread adoption of naloxone administration by law enforcement officers in NYS is a powerful example of the successful integration of a public health intervention into police work.

DO HIGHER DOSES OF NALOXONE INCREASE THE RISK OF PULMONARY COMPLICATIONS?

BACKGROUND

Although naloxone has proven to be an effective opioid reversal agent, concern that high doses of naloxone can cause pulmonary edema may prevent health care providers from administering it in initial high doses.

OBJECTIVE

Our aim was to determine whether increased doses of naloxone are correlated with an increase in pulmonary complications in patients presenting to the emergency department (ED) after an opioid overdose.

METHODS

This was a retrospective study of patients treated with naloxone by emergency medical services (EMS) or in the ED at an urban level I trauma center and three associated freestanding EDs. Data were queried from EMS run reports and the medical record and included demographic characteristics, naloxone dosing, administration route, and pulmonary complications. Patients were grouped by naloxone dose received, defined as low (≤ 2 mg), moderate (> 2 mg to ≤ 4 mg), and high (> 4 mg).

RESULTS

Of the 639 patients included, 13 (2.0%) were diagnosed with a pulmonary complication. There was no difference in the development of pulmonary complications across groups (p = 0.676). There was no difference in pulmonary complications based on the route of administration (p = 0.342). The administration of higher doses of naloxone was not associated with longer hospital stays (p = 0.0327).

CONCLUSIONS

Study results suggest that the reluctance of many health care providers to administer larger doses of naloxone on initial treatment may not be warranted. In this investigation, there were no poor outcomes associated with an increase in naloxone administration. Further investigation in a more diverse population is warranted.

High-potency benzodiazepine misuse in opioid-dependent patients: use naloxone with care

The misuse of highly potent benzodiazepines is increasing in the UK, particularly among the opioid-using population in Scotland. Differentiating opioid from benzodiazepine toxicity is not always straightforward in patients with reduced level of consciousness following drug overdose. Patients on long-term opioid substitution who present with acute benzodiazepine intoxication and are given naloxone may develop severe opioid withdrawal while still obtunded from benzodiazepines. This situation can be difficult to manage, and these patients may be at increased risk of vomiting while still unable to protect their airway. Fortunately, the short half-life of naloxone means that the situation is generally short-lived. Naloxone should never be withheld from patients with life-threatening respiratory depression where opioids may be contributing, particularly in community and prehospital settings; however, where appropriate clinical experience exists, naloxone should ideally be administered in small incremental intravenous doses with close monitoring of respiratory function. Increased awareness of the potential risks of naloxone in opioid-dependent patients acutely intoxicated with benzodiazepines may reduce the risk of iatrogenic harm in an already very vulnerable population.

Patching holes in the mechanism of opioid tolerance

Tolerance is a significant obstacle to use of opioids as safe pain relieving drugs, but the cellular processes that result in tolerance have remained elusive. A new study by Maza and colleagues identifies the protein Patched domain-containing 1 (PTCHD1) and its effects on cellular cholesterol as potential targets for preventing opioid tolerance.

College students' knowledge about opioids and implications for the opioid crisis

OBJECTIVE

This study assessed undergraduate unhealthy substance use, levels of knowledge about opioid pharmacology, unhealthy use and safety, and students' perceptions about their level of knowledge.

PARTICIPANTS

Participants were undergraduate students at a large, private university in the Northeast.

METHODS

This study employed a cross-sectional study design using an online survey. A convenience sample of undergraduate students (N = 317) described their actual and perceived levels of opioid knowledge and their self-reported substance use.

RESULTS

Objective answers to quiz-style questions about opioids showed knowledge deficits. Participants rated themselves as slightly less knowledgeable than the "average student." Ten percent of students surveyed had used opioids unhealthily at some point in their lifetime. Those reporting unhealthy opioid use had higher subjective and objective opioid knowledge scores.

CONCLUSIONS

University students' subjective and objective knowledge of opioids warrants more effective and engaging substance use education on college campuses.