Review of naloxone safety for opioid overdose: practical considerations for new technology and expanded public access

High-dose naloxone formulations are not as essential as we thought

Naloxone is an effective 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 investigates the adequacy of two doses of standard IM or IN naloxone in reversing fentanyl overdoses compared to newer high-dose naloxone formulations. Moreover, our initiative incorporates the experiences of people who use drugs, enabling a more practical and contextually-grounded analysis. The evidence indicates that the vast majority of fentanyl overdoses can be successfully reversed using two standard IM or IN dosages. Exceptions include cases of carfentanil overdose, which necessitates ≥ 3 doses for reversal. Multiple studies documented the risk of precipitated withdrawal using ≥ 2 doses of naloxone, notably including the possibility of recurring overdose symptoms after resuscitation, contingent upon the half-life of the specific opioid involved. We recommend distributing multiple doses of standard IM or IN naloxone to bystanders and educating individuals on the adequacy of two doses in reversing fentanyl overdoses. Individuals should continue administration until the recipient is revived, ensuring appropriate intervals between each dose along with rescue breaths, and calling emergency medical services if the individual is unresponsive after two doses. We do not recommend high-dose naloxone formulations as a substitute for four doses of IM or IN naloxone due to the higher cost, risk of precipitated withdrawal, and limited evidence compared to standard doses. Future research must take into consideration lived and living experience, scientific evidence, conflicts of interest, and the bodily autonomy of people who use drugs.

Psychosocial factors associated with overdose subsequent to Illicit Drug use: a systematic review and narrative synthesis

BACKGROUND AND AIMS

Psychological and social status, and environmental context, may mediate the likelihood of experiencing overdose subsequent to illicit drug use. The aim of this systematic review was to identify and synthesise psychosocial factors associated with overdose among people who use drugs.

METHODS

This review was registered on Prospero (CRD42021242495). Systematic record searches were undertaken in databases of peer-reviewed literature (Medline, Embase, PsycINFO, and Cinahl) and grey literature sources (Google Scholar) for work published up to and including 14 February 2023. Reference lists of selected full-text papers were searched for additional records. Studies were eligible if they included people who use drugs with a focus on relationships between psychosocial factors and overdose subsequent to illicit drug use. Results were tabulated and narratively synthesised.

RESULTS

Twenty-six studies were included in the review, with 150,625 participants: of those 3,383-4072 (3%) experienced overdose. Twenty-one (81%) studies were conducted in North America and 23 (89%) reported polydrug use. Psychosocial factors associated with risk of overdose (n = 103) were identified and thematically organised into ten groups. These were: income; housing instability; incarceration; traumatic experiences; overdose risk perception and past experience; healthcare experiences; perception of own drug use and injecting skills; injecting setting; conditions with physical environment; and social network traits.

CONCLUSIONS

Global rates of overdose continue to increase, and many guidelines recommend psychosocial interventions for dependent drug use. The factors identified here provide useful targets for practitioners to focus on at the individual level, but many identified will require wider policy changes to affect positive change. Future research should seek to develop and trial interventions targeting factors identified, whilst advocacy for key policy reforms to reduce harm must continue.

Users' Acceptability and Perceived Efficacy of mHealth for Opioid Use Disorder: Scoping Review

BACKGROUND

The opioid crisis continues to pose significant challenges to global public health, necessitating the development of novel interventions to support individuals in managing their substance use and preventing overdose-related deaths. Mobile health (mHealth), as a promising platform for addressing opioid use disorder, requires a comprehensive understanding of user perspectives to minimize barriers to care and optimize the benefits of mHealth interventions.

OBJECTIVE

This study aims to synthesize qualitative insights into opioid users' acceptability and perceived efficacy of mHealth and wearable technologies for opioid use disorder.

METHODS

A scoping review of PubMed (MEDLINE) and Google Scholar databases was conducted to identify research on opioid user perspectives concerning mHealth-assisted interventions, including wearable sensors, SMS text messaging, and app-based technology.

RESULTS

Overall, users demonstrate a high willingness to engage with mHealth interventions to prevent overdose-related deaths and manage opioid use. Users perceive mHealth as an opportunity to access care and desire the involvement of trusted health care professionals in these technologies. User comfort with wearing opioid sensors emerged as a significant factor. Personally tailored content, social support, and encouragement are preferred by users. Privacy concerns and limited access to technology pose barriers to care.

CONCLUSIONS

To maximize benefits and minimize risks for users, it is crucial to implement robust privacy measures, provide comprehensive user training, integrate behavior change techniques, offer professional and peer support, deliver tailored messages, incorporate behavior change theories, assess readiness for change, design stigma-reducing apps, use visual elements, and conduct user-focused research for effective opioid management in mHealth interventions. mHealth demonstrates considerable potential as a tool for addressing opioid use disorder and preventing overdose-related deaths, given the high acceptability and perceived benefits reported by users.

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.

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.

Fact vs. fiction: naloxone in the treatment of opioid-induced respiratory depression in the current era of synthetic opioids

Opioid-induced respiratory depression (OIRD) deaths are ~80,000 a year in the US and are a major public health issue. Approximately 90% of fatal opioid-related deaths are due to synthetic opioids such as fentanyl, most of which is illicitly manufactured and distributed either on its own or as an adulterant to other drugs of abuse such as cocaine or methamphetamine. Other potent opioids such as nitazenes are also increasingly present in the illicit drug supply, and xylazine, a veterinary tranquilizer, is a prevalent additive to opioids and other drugs of abuse. Naloxone is the main treatment used to reverse OIRD and is available as nasal sprays, prefilled naloxone injection devices, and generic naloxone for injection. An overdose needs to be treated as soon as possible to avoid death, and synthetic opioids such as fentanyl are up to 50 times more potent than heroin, so the availability of new, higher-dose, 5-mg prefilled injection or 8-mg intranasal spray naloxone preparations are important additions for emergency treatment of OIRDs, especially by lay people in the community. Higher naloxone doses are expected to reverse a synthetic overdose more rapidly and the current formulations are ideal for use by untrained lay people in the community. There are potential concerns about severe withdrawal symptoms, or pulmonary edema from treatment with high-dose naloxone. However, from the perspective of first responders, the balance of risks would point to administration of naloxone at the dose required to combat the overdose where the risk of death is very high. The presence of xylazines as an adulterant complicates the treatment of OIRDs, as naloxone is probably ineffective, although it will reverse the respiratory depression due to the opioid. For these patients, hospitalization is particularly vital. Education about the benefits of naloxone remains important not only in informing people about how to treat emergency OIRDs but also how to obtain naloxone. A call to emergency services is also essential after administering naloxone because, although the patient may revive, they may overdose again later because of the short half-life of naloxone and the long-lasting potency of fentanyl and its analogs.

Epidemiological Aspects of Opioid Poisoning in Northern Iran: A Registry-Based Clinical Study

Opioids are a class of drugs that are commonly used to manage pain due to their analgesic and sedative effects. However, the high consumption of opioids in the community has led to an increase in the incidence of overdoses and poisonings caused by various types of these drugs, whether intentional or unintentional. Therefore, comprehending the epidemiological features of patients experiencing opioid poisoning is crucial. We decided to investigate various epidemiological aspects of patients with opioid poisoning in the Mazandaran province, located in northern Iran, during the period of 2020 to 2021. The present investigation was conducted as a descriptive cross-sectional study, wherein we collected data on patients registered in the Mazandaran Registry Center of Opioid Poisoning (MRCOP) who had a history of using any kind of opioid. We collected information on various parameters, including patient demographics, the type of opioid consumed, the mode of consumption, and clinical outcomes. A total of 240 patients were initially registered at the registry center. However, 17 cases were excluded with personal consent, and eventually, a total of 223 patients were included in the investigation. The majority of the patients 70.9% (n = 158) were male, and the average age was 34.4 ± 16.55 years. The most common cause of poisoning reported in our study was intentional, which was mainly due to a suicide attempt. Furthermore, the most prevalent type of opioid consumed was methadone. The most frequently observed symptoms of poisoning among the patients were drowsiness, a decreased level of consciousness, and reduced arterial oxygen saturation levels. Based on the results of our study, several factors were found to be significant in methadone poisoning, including addiction, age, gender, suicide attempt, and a history of psychiatric disorder. These findings highlight the need for public education and awareness campaigns on the risks associated with opioid use, particularly methadone.

Harm reduction workforce, behavioral health, and service delivery in the USA: a cross-sectional study

BACKGROUND

Despite recent financial and policy support for harm reduction in the USA, information on the types of workers within organizations who design, implement, and actualize harm reduction services remains nascent. Little is known about how variability in the harm reduction workforce impacts referrals and linkages to other community supports. This exploratory mixed-methods study asked: (1) Who constitutes the harm reduction workforce? (2) Who provides behavioral health services within harm reduction organizations? (3) Are referral services offered and by whom? (4) Do referrals differ by type of harm reduction worker?

METHODS

Purposive sampling techniques were used to distribute an electronic survey to U.S.-based harm reduction organizations. Descriptive statistics were conducted. Multivariate binary logistic regression models examined the associations (a) between the odds of the referral processes at harm reduction organizations and (b) between the provision of behavioral health services and distinct types of organizational staff. Qualitative data were analyzed using a hybrid approach of inductive and thematic analysis.

RESULTS

Data from 41 states and Washington, D.C. were collected (N = 168; 48% response rate). Four primary types of workers were identified: community health/peer specialists (87%); medical/nursing staff (55%); behavioral health (49%); and others (34%). About 43% of organizations had a formal referral process; among these, only 32% had follow-up protocols. Qualitative findings highlighted the broad spectrum of behavioral health services offered and a broad behavioral health workforce heavily reliant on peers. Unadjusted results from multivariate models found that harm reduction organizations were more than 5 times more likely (95% CI [1.91, 13.38]) to have a formal referral process and 6 times more likely (95% CI [1.74, 21.52]) to have follow-up processes when behavioral health services were offered. Organizations were more than two times more likely (95% CI [1.09, 4.46]) to have a formal referral process and 2.36 (95% CI [1.11, 5.0]) times more likely to have follow-up processes for referrals when behavioral health providers were included.

CONCLUSIONS

The composition of the harm reduction workforce is occupationally diverse. Understanding the types of services offered, as well as the workforce who provides those services, offers valuable insights into staffing and service delivery needs of frontline organizations working to reduce morbidity and mortality among those who use substances. Workforce considerations within U.S.-based harm reduction organizations are increasingly important as harm reduction services continue to expand.

Interventions to increase naloxone access for undergraduate students: A systematic review of the literature

OBJECTIVE

To identify and describe interventions that increase access to naloxone for undergraduate students.

METHODS

A systematic review across 4 databases identified interventions that expand access to naloxone at colleges in the United States from 2015-2023. Three reviewers extracted the following data to create a narrative synthesis and summary of program elements: setting, rationale for intervention, timeline, intervention components, study size, collaboration, sustainability, outcomes and results.

RESULTS

Seven articles met inclusion criteria. Institutions' implemented naloxone interventions due to concerns for student safety and/or student overdose fatalities. Three universities collaborated with their School of Pharmacy for program design and/or dissemination, while two partnered with state-based naloxone distribution programs. Most programs combined opioid-overdose/naloxone training; four distributed naloxone kits. Three studies included pre/post-outcomes, and all reported increases in participant knowledge, attitudes, and/or ability to respond to an overdose.

CONCLUSIONS

Our results indicates an opportunity for wide-scale implementation of undergraduate naloxone programs within US colleges. However, more rigorous implementation research is needed to identify barriers and facilitators to program feasibility, acceptability, and participation.

Remaking the 'angry Narcanned subject': Affording new subject positions through take-home naloxone training

Naloxone is a medication used to reverse opioid overdose. Alongside its lifesaving effects, it also has a reputation for producing distress, aggression and occasionally violence upon administration. This article analyses how take-home naloxone (THN) training initiatives address naloxone's reputation for producing aggression and conflict, and how new subject positions emerge in the context of this training. While the role of naloxone in producing aggression has been discussed in a range of research, this work emphasises that such conflict is neither inevitable nor even likely because it is contingent on several other issues such as administration practices. Building on this scholarship, we work with Bruno Latour's theorisation of technological 'affordances' to analyse THN as a socially co-produced technology that, rather than either determining or neutrally communicating actions and effects, 'affords' possibilities, capacities and subjects. Analysing data drawn from observations of THN training in Victoria, Australia, and in-depth interviews with training participants, we argue that the issue of conflict upon revival affords a subject position we term the 'angry Narcanned subject'. This subject, we note, has come to hold a powerful position in understandings of naloxone, not least because it tends to accord with stereotypes of antisocial drug users. From here, we argue that a much of THN training is focused on challenging and reframing naloxone's reputation for conflict and questioning related subject positions, especially that of the angry Narcanned subject. We argue that this process of challenging and reframing affords two new subject positions for consumers: the 'capable administrator' and the 'calmer revivee'. We conclude that while THN training affords multiple, potentially positive, subject positions, unless these initiatives are accompanied by broader interventions such as decriminalisation campaigns, they may inadvertently responsibilise people who consume opioids for addressing overdose and erase the role of prohibition, criminalisation and stigmatisation in producing overdose events.

On-Demand Opioid Effect Reversal with an Injectable Light-Triggered Polymer-Naloxone Conjugate

Misuse of opioids can lead to a potential lethal overdose. Timely administration of naloxone is critical for survival. Here, we designed a polymer-naloxone conjugate that can provide on-demand phototriggered opioid reversal. Naloxone was attached to the polymer poly(lactic-co-glycolic acid) via a photocleavable coumarin linkage and formulated as injectable nanoparticles. In the absence of irradiation, the formulation did not release naloxone. Upon irradiation with blue (400 nm) light, the nanoparticles released free naloxone, reversing the effect of morphine in mice. Such triggered events could be performed days and weeks after the initial administration of the nanoparticles and could be performed repeatedly.

Human IPSC-Derived PreBötC-Like Neurons and Development of an Opiate Overdose and Recovery Model

Opioid overdose is the leading cause of drug overdose lethality, posing an urgent need for investigation. The key brain region for inspiratory rhythm regulation and opioid-induced respiratory depression (OIRD) is the preBötzinger Complex (preBötC) and current knowledge has mainly been obtained from animal systems. This study aims to establish a protocol to generate human preBötC neurons from induced pluripotent cells (iPSCs) and develop an opioid overdose and recovery model utilizing these iPSC-preBötC neurons. A de novo protocol to differentiate preBötC-like neurons from human iPSCs is established. These neurons express essential preBötC markers analyzed by immunocytochemistry and demonstrate expected electrophysiological responses to preBötC modulators analyzed by patch clamp electrophysiology. The correlation of the specific biomarkers and function analysis strongly suggests a preBötC-like phenotype. Moreover, the dose-dependent inhibition of these neurons' activity is demonstrated for four different opioids with identified IC50's comparable to the literature. Inhibition is rescued by naloxone in a concentration-dependent manner. This iPSC-preBötC mimic is crucial for investigating OIRD and combating the overdose crisis and a first step for the integration of a functional overdose model into microphysiological systems.

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.

Characterizing and combating the opioid epidemic in the Los Angeles County jail system

INTRODUCTION

Opioid overdose-related morbidity and mortality is a pressing public health crisis. Successful overdose reversal through bystander administration of naloxone is well documented, but there is an absence of literature on the implementation and impact of widespread naloxone access in a correctional setting during incarceration. The objective of this study was to describe our efforts to combat opioid overdose, prevent deaths, and examine and identify opioid use and predictors of opioid use through factors including age, sex assigned at birth, and ethnicity among the incarcerated population within the Los Angeles County jail system.

METHODS

We retrospectively analyzed self-reported substance use information from all newly incarcerated persons from September 2018 to December 2020 to characterize opioid use in the Los Angeles County Jail system and used multivariable logistic regression analysis to determine predictors of substance use. We analyzed data on all cases of naloxone administration by custody personnel (i.e., all correctional officers) during the same period by examining patient demographic information, hospital discharge diagnosis, and patient outcome information. To describe naloxone training and access for incarcerated persons as an overdose prevention strategy, we reviewed electronic health record data on patient health outcomes for all cases of naloxone administration by an incarcerated person.

RESULTS

A total of 6.4 % (11,881 of 187,528) of incarcerated persons reported opioid use. In the multivariable analysis, reported substance use was most significantly associated with any ethnicity other than Black (aOR for White =11.2; 95 % CI 10.4, 12.0, aOR for Hispanic/Latinx 3.0; 95 % CI 2.8, 3.2, aOR for All Others; 5.2 95 % CI 4.6, 5.8) and being <65 years old. Naloxone was administered by custody personnel to a total of 129 patients, where 122 (94.6 %) survived and 7 (5.4 %) died. After the deployment of naloxone in jail housing units, there were two instances of bystander naloxone administration by incarcerated persons that led to successful opioid overdose reversal and survival.

CONCLUSIONS

The expansion of naloxone availability to both custody personnel and incarcerated persons is an effective and warranted method to ensure timely naloxone administration and successful overdose reversal in a correctional setting.

Differences in Self-identification of Opioid Overdose Risk and Naloxone Perceptions Between Therapeutic and Nontherapeutic Opioid Populations

OBJECTIVES

Efforts to improve low naloxone uptake to mitigate the current opioid crisis have included coprescribing naloxone with opioid medications and, more recently, expansion through over-the-counter availability, the latter of which necessitates self-identification of overdose risk by consumers. This study sought to understand perceptions of opioid overdose risk and naloxone among distinct opioid populations at elevated risk for overdose.

METHODS

A cross-sectional, online survey was provided to 2 opioid populations in June 2020. First, chronic pain opioid managed (CPOM; n = 190) individuals currently treated with an opioid prescription (either >50 daily morphine milligram equivalents [73.2%] or benzodiazepine co-use [52.6%]), restricted by confounders. Second, individuals with a history of opioid use disorder (OUD; n = 152) previously participating in a national opioid surveillance study of new entrants to substance use treatment centers.

RESULTS

Risk perceptions significantly differed, with 60.0% (CPOM) versus 28.9% (OUD) reporting that they were "not at all concerned about overdosing," and 62.1% (CPOM) versus 19.1% (OUD) perceiving themselves as having "no risk" of overdose. Perceived need for naloxone was lower among CPOM versus OUD patients (48.3% and 71.8%, respectively), whereas 22.6% and 35.0%, respectively, indicated any likelihood of obtaining naloxone in the future.

CONCLUSIONS

Results suggest that a significant proportion of both samples lacked the ability to self-identify their risk of overdose and self-select themselves as needing naloxone, with gaps being more prominent in the CPOM sample. A multi-intervention framework that addresses distinct pathways of behavioral change between unique opioid populations should be considered in conversations surrounding potential transitions to over-the-counter naloxone.

Iron Acquisition Proteins of Pseudomonas aeruginosa as Potential Vaccine Targets: In Silico Analysis and In Vivo Evaluation of Protective Efficacy of the Hemophore HasAp

BACKGROUND

Pseudomonas aeruginosa (PA) is a Gram-negative pathogen responsible for fatal nosocomial infections worldwide. Iron is essential for Gram-negative bacteria to establish an infection. Therefore, iron acquisition proteins (IAPs) of bacteria are attractive vaccine targets.

METHODOLOGY

A "Reverse Vaccinology" approach was employed in the current study. Expression levels of 37 IAPs in various types of PA infections were analyzed in seven previously published studies. The IAP vaccine candidate was selected based on multiple criteria, including a high level of expression, high antigenicity, solubility, and conservation among PA strains, utilizing suitable bioinformatics analysis tools. The selected IAP candidate was recombinantly expressed in Escherichia coli and purified using metal affinity chromatography. It was further evaluated in vivo for protection efficacy. The novel immune adjuvant, naloxone (NAL), was used.

RESULTS AND DISCUSSION

HasAp antigen met all the in silico selection criteria, being highly antigenic, soluble, and conserved. In addition, it was the most highly expressed IAP in terms of average fold change compared to control. Although HasAp did excel in the in silico evaluation, subcutaneous immunization with recombinant HasAp alone or recombinant HasAp plus NAL (HasAP-NAL) did not provide the expected protection compared to controls. Immunized mice showed a low IgG2a/IgG1 ratio, indicating a T-helper type 2 (Th2)-oriented immune response that is suboptimal for protection against PA infections. Surprisingly, the bacterial count in livers of both NAL- and HasAp-NAL-immunized mice was significantly lower than the count in the HasAp and saline groups. The same trend was observed in kidneys and lungs obtained from these groups, although the difference was not significant. Such protection could be attributed to the enhancement of innate immunity by NAL.

CONCLUSIONS

We provided a detailed in silico analysis of IAPs of PA followed by in vivo evaluation of the best IAP, HasAp. Despite the promising in silico results, HasAp did not provide the anticipated vaccine efficacy. HasAp should be further evaluated as a vaccine candidate through varying the immunization regimens, models of infection, and immunoadjuvants. Combination with other IAPs might also improve vaccination efficacy. We also shed light on several highly expressed promising IAPs whose efficacy as vaccine candidates is worthy of further investigation.

Qualitative exploration of public health vending machines in young adults who misuse opioids: A promising strategy to increase naloxone access in a high risk underserved population

Background

Take home naloxone (THN) programs have been shown to effectively reverse opioid overdose events with limited adverse events, yet often miss young adults who use opioids. To identify opportunities for naloxone expansion, we conducted interviews with young adults who had used opioids. We explored young adults' experience with current THN programs, and perspectives on ideal THN programs and emerging naloxone public health vending machine (PHVM) programs shown to increase access to sterile syringes in young adults.

Methods

We interviewed 16 young adults receiving substance treatment services within an integrated safety net healthcare system. Participants were 18-30 years of age with a history of nonmedical prescription opioid use. Interviews obtained the patient perspective of current THN, ideal THN and PHVM programs. Interviews were transcribed and coded by team-based methods. Themes were developed using an inductive-deductive iterative approach and defined through consensus.

Results

Treatment was often the first exposure to naloxone. Participants recommended easy to access programs for ideal naloxone distribution and had overall positive feedback on PHVMs. Three key themes were identified to improve naloxone uptake: knowledge, convenience, and privacy. Participants identified safety, lack of police presence, and low costs as important vending machine features.

Conclusions

Our results identified implementation opportunities to increase naloxone uptake including convenient location and hours, privacy, and using trusted sources of information to improve program awareness. PHVMs present an opportunity to maximize these opportunities and increase access to naloxone in young adults.

Naloxone administration by law enforcement officers in New York State (2015-2020)

BACKGROUND

The COVID-19 pandemic has amplified the need for wide deployment of effective harm reduction strategies in preventing opioid overdose mortality. Placing naloxone in the hands of key responders, including law enforcement officers who are often first on the scene of a suspected overdose, is one such strategy. New York State (NYS) was one of the first states to implement a statewide law enforcement naloxone administration program. This article provides an overview of the law enforcement administration of naloxone in NYS between 2015 and 2020 and highlights key characteristics of over 9000 opioid overdose reversal events.

METHODS

Data in naloxone usage report forms completed by police officers were compiled and analyzed. Data included 9133 naloxone administration reports by 5835 unique officers located in 60 counties across NYS. Descriptive statistics were used to examine attributes of the aided individuals, including differences between fatal and non-fatal incidents. Additional descriptive analyses were conducted for incidents in which law enforcement officers arrived first at the scene of suspected overdose. Comparisons were made to examine year-over-year trends in administration as naloxone formulations were changed. Quantitative analysis was supplemented by content analysis of officers' notes (n = 2192).

RESULTS

In 85.9% of cases, law enforcement officers arrived at the scene of a suspected overdose prior to emergency medical services (EMS) personnel. These officers assessed the likelihood of an opioid overdose having occurred based on the aided person's breathing status and other information obtained on the scene. They administered an average of 2 doses of naloxone to aided individuals. In 36.8% of cases, they reported additional administration of naloxone by other responders including EMS, fire departments, and laypersons. Data indicated the aided survived the suspected overdose in 87.4% of cases.

CONCLUSIONS

With appropriate training, law enforcement personnel were able to recognize opioid overdoses and prevent fatalities by administering naloxone and carrying out time-sensitive medical interventions. These officers provided life-saving services to aided individuals alongside other responders including EMS, fire departments, and bystanders. Further expansion of law enforcement naloxone administration nationally and internationally could help decrease opioid overdose mortality.

Individual Medical Emergencies Occurring at School

Children and adults may face emergency medical situations because of injuries, complications of chronic health conditions, or unexpected major illnesses that occur in schools. The American Academy of Pediatrics published a policy statement in 2001 titled "Guidelines for Emergency Medical Care in Schools," and in 2008, published its revision, "Medical Emergencies Occurring at School." Those statements focused on the preparedness of schools to address individual student emergencies. The increase in the number of children with special health care needs and chronic medical conditions attending schools, together with the added challenges faced by school districts to ensure that schools have access to on-site, licensed health care professionals on an ongoing basis, have contributed to added risks that medical and nonmedical personnel face in dealing with medical emergencies in schools. This newly revised policy statement serves as an update of the statement published in 2008 and reaffirmed in 2017, and intends to increase pediatricians' awareness of schools' roles in preparing for individual student emergencies and provide recommendations for the medical home and school physicians on how to assist and support school personnel. This statement does not address schoolwide or communitywide emergencies that might occur as a result of natural or man-made disasters.

Evaluating the population-level effects of overdose prevention sites and supervised consumption sites in British Columbia, Canada: Controlled interrupted time series

Background

On 14 April 2016, British Columbia’s Provincial Medical Health Officer declared the overdose crisis a public health emergency, sanctioning the implementation of new overdose prevention sites (OPS) and supervised consumption sites (SCS) across the province.

Methods

We used the BC Centre for Disease Control’s Provincial Overdose Cohort of all overdose events between 1 January 2015 and 31 December 2017 to evaluate the population-level effects of OPSs and SCSs on acute health service use and mortality. We matched local health areas (LHA) that implemented any site with propensity score matched controls and conducted controlled interrupted time series analysis.

Results

During the study period, twenty-five OPSs and SCSs opened across fourteen of British Columbia’s 89 LHAs. Results from analysis of LHAs with matched controls (i.e. excluding Vancouver DTES) were mixed. Significant declines in reported overdose events, paramedic attendance, and emergency department visits were observed. However, there were no changes to trends in monthly hospitalization or mortality rates. Extensive sensitivity analyses found these results persisted.

Conclusions

We found OPSs and SCSs reduce opioid-related paramedic attendance and emergency department visit rates but no evidence that they reduce local hospitalization or mortality rates.

Ineffectiveness of paramedic naloxone administration as a standalone metric for community opioid overdoses and the increasing use of naloxone by community members

Introduction:With Canada's growing opioid crisis, many communities are attempting to monitor cases in real-time. Paramedic Naloxone Administration (PNA) has become a common metric for monitoring overdoses. We evaluate whether the use of naloxone administration counts represents an effective monitoring tool for community opioid overdoses.Methods:The electronic ambulance call report database of Peterborough Paramedics (Ontario, Canada) was examined. De-identified records from 2016-2019 with problem codes of "Opioid Overdose", along with all patients documented as receiving naloxone were extracted. Chi-square and Bonferroni-adjusted post hoc proportion tests were used for comparison of counts.Results:558 opioid overdoses were identified, 124 (22%) of which had PNA documented, 181(32%) had naloxone prior to arrival documented and 264 (47%) received no naloxone. Over the three years, the annual number of overdose cases increased, while the proportion of patients receiving PNA decreased significantly each year. PNA was also associated with calls in a residence. Naloxone was administered by a non-paramedic in 262 cases, with 181 of these identified as opioid overdoses and was more common in later years and in cases occurring in public places.Conclusion:PNA calls did not account for a significant percentage of opioid overdoses attended to by paramedics. The strong association between PNA and call location being a residence, along with increasing use of community naloxone kits, may cause certain populations to be under-represent if PNA is used as a standalone metric. The decreasing association with time may also lead to a falsely improving metric further reducing its effectiveness. Thus, PNA when used alone may no longer be a suitable metric for opioid overdose tracking.

Broadening access to naloxone: Community predictors of standing order naloxone distribution in Massachusetts

BACKGROUND

Naloxone is a prescription medication that reverses opioid overdoses. Allowing naloxone to be dispensed directly by a pharmacist without an individual prescription under a naloxone standing order (NSO) can expand access. The community-level factors associated with naloxone dispensed under NSO are unknown.

METHODS

Using a dataset comprised of pharmacy reports of naloxone dispensed under NSO from 70% of Massachusetts retail pharmacies, we examined relationships between community-level demographics, rurality, measures of treatment for opioid use disorder, and overdose deaths with naloxone dispensed under NSO per ZIP Code-quarter from 2014 until 2018. We used a multi-variable zero-inflated negative binomial model, assessing odds of any naloxone dispensed under NSO, as well as a multi-variable negative binomial model assessing quantities of naloxone dispensed under NSO.

RESULTS

From 2014-2018, quantities of naloxone dispensed under NSO and the number of pharmacies dispensing any naloxone under NSO increased over time. However, communities with greater percentages of people with Hispanic ethnicity (aOR 0.91, 95% CI 0.86-0.96 per 5% increase), and rural communities compared to urban communities (aOR 0.81, 95% CI 0.73-0.90) were less likely to dispense any naloxone by NSO. Communities with more individuals treated with buprenorphine dispensed more naloxone under NSO, as did communities with more opioid-related overdose deaths.

CONCLUSION

Naloxone dispensing has substantially increased, in part driven by standing orders. A lower likelihood of naloxone being dispensed under NSO in communities with larger Hispanic populations and in more rural communities suggests the need for more equitable access to, and uptake of, lifesaving medications like naloxone.

Effectiveness and implementability of state-level naloxone access policies: Expert consensus from an online modified-Delphi process

BACKGROUND

Naloxone distribution, a key global strategy to prevent fatal opioid overdose, has been a recent target of legislation in the U.S., but there is insufficient empirical evidence from causal inference methods to identify which components of these policies successfully reduce opioid-related harms. This study aimed to examine expert consensus on the effectiveness and implementability of various state-level naloxone policies.

METHODS

We used the online ExpertLens platform to conduct a three-round modified-Delphi process with a purposive sample of 46 key stakeholders (advocates, healthcare providers, human/social service practitioners, policymakers, and researchers) with naloxone policy expertise. The Effectiveness Panel (n = 24) rated average effects of 15 types of policies on naloxone pharmacy distribution, opioid use disorder (OUD) prevalence, nonfatal opioid-related overdoses, and opioid-related overdose mortality. The Implementation Panel (n = 22) rated the same policies on acceptability, feasibility, affordability, and equitability. We compared ratings across policies using medians and inter-percentile ranges, with consensus measured using the RAND/UCLA Appropriateness Method Inter-Percentile Range Adjusted for Symmetry technique.

RESULTS

Experts reached consensus on all items. Except for liability protections and required provision of education or training, experts perceived all policies to generate moderate-to-large increases in naloxone pharmacy distribution. However, only three policies were expected to yield substantive decreases on fatal overdose: statewide standing/protocol order, over-the-counter supply, and statewide "free naloxone." Of these, experts rated only statewide standing/protocol orders as highly affordable and equitable, and unlikely to generate meaningful population-level effects on OUD or nonfatal opioid-related overdose. Across all policies, experts rated naloxone prescribing mandates relatively lower in acceptability, feasibility, affordability, and equitability.

CONCLUSION

Experts believe statewide standing/protocol orders are an effective, implementable, and equitable policy for addressing opioid-related overdose mortality. While experts believe many other broad policies are effective in reducing opioid-related harms, they also believe these policies face implementation challenges related to cost and reaching vulnerable populations.

Isolation, Identification and Structural Verification of a Methylene-Bridged Naloxone "Dimer" Formed by Formaldehyde

We report the isolation and characterization of a methylene bridged "dimer" of the opioid antagonist Naloxone, previously detected in experimental Buprenorphine-Naloxone oral films. This compound was found to form via an aldol addition followed by a condensation reaction under acidic conditions between two units of Naloxone and one unit of formaldehyde. HPLC-UV-HRMS analysis revealed the formation of three individual stereoisomers during this reaction, which were separately isolated using solid-phase extraction. These isomers were shown to freely react into one another in solvent, forming an equilibrium. The structure of the unknown compound was determined via HRMS spectrometry and 1D and 2D NMR spectroscopy.

Adverse events related to bystander naloxone administration in cases of suspected opioid overdose in British Columbia: An observational study

Introduction

Take-Home Naloxone programs have been introduced across North America in response to rising opioid overdose deaths. There is currently limited real-world data on bystander naloxone administration, overdose outcomes, and evidence related to adverse events following bystander naloxone administration.

Methods

The research team used descriptive statistics from Take-Home Naloxone administration forms. We explored reported demographic variables and adverse events among people who received by-stander administered naloxone in a suspected opioid overdose event between August 31, 2012 and December 31, 2018 in British Columbia. We examined and contextualized differences across years given policy, program and drug toxicity changes. We used multivariate logistic regression to examine whether an association exists between number of ampoules of naloxone administered and the odds that the recipient will experience withdrawal symptoms.

Results

A large majority (98.1%) of individuals who were administered naloxone survived their overdose and 69.2% had no or only mild withdrawal symptoms. Receiving three (Adjusted Odds Ratio (AOR) 1.64 (95% Confidence Interval (CI): 1.08–2.48)) or four or more (AOR 2.19 (95% CI: 1.32–3.62)) ampoules of naloxone was significantly associated with odds of moderate or severe withdrawal compared to receiving one ampoule of naloxone.

Conclusions

This study provides evidence from thousands of bystander reversed opioid overdoses using Take-Home Naloxone kits in British Columbia, and suggests bystander-administered naloxone is safe and effective for opioid overdose reversal. Data suggests an emphasis on titration during bystander naloxone training in situations where the person experiencing overdose can be adequately ventilated may help avoid severe withdrawal symptoms. We identified a decreasing trend in the likelihood of moderate or severe withdrawal over the study period.

Fentanyl causes naloxone-resistant vocal cord closure: A platform for testing opioid overdose treatments

BACKGROUND

High doses of the synthetic opioid fentanyl cause rapid and sustained vocal cord closure (VCC) leading to airway obstruction that prevents overdose victims from breathing. This airway effect is not caused by morphine-derived opiates (e.g. heroin), is distinct from respiratory depression, resistant to naloxone, and can be lethal. However, VCC has not been previously included in animal models of opioid overdose.

METHODS

Video laryngoscopy was used to monitor vocal cord movement in anesthetized Sprague-Dawley rats. Rats were administered saline, fentanyl (5, 25, or 50 μg/kg) or morphine (5 mg/kg) in an intravenous (IV) bolus delivered over a 10 s period. The mu opioid receptor (MOR) antagonist naloxone was administered as a pre-treatment (1 mg/kg, IV) 5 min prior to fentanyl (25 μg/kg) or a post-treatment (1 and 2 mg/kg) 1 min after fentanyl (25 μg/kg).

RESULTS

Fentanyl (25 and 50 μg/kg) caused sustained and lethal VCC within 10 s. Morphine (5 mg/kg) and fentanyl (5 μg/kg) caused only brief laryngospasm with full recovery. Pre-treatment with naloxone (1 mg/kg) prevented fentanyl-induced VCC, but naloxone (1 and 2 mg/kg) was unable to reverse VCC when administered after fentanyl.

CONCLUSIONS

These results indicate sustained VCC is a lethal physiological reaction, specific to fentanyl and resistant to naloxone treatment. While pre-treatment with naloxone prevented fentanyl-induced VCC, naloxone was unable to reverse the effect, suggesting a non-opioid receptor-mediated mechanism. These findings demonstrate the necessity of VCC inclusion in animal models of synthetic opioid overdose and the urgent need for more effective treatments for fentanyl-related overdoses.

Multi-informant Implementation and Intervention Outcomes of Opioid Overdose Education and Naloxone Distribution in New York City

Overdose Education and Naloxone Distribution (OEND) is an effective public health intervention to reduce opioid overdose fatalities (McDonald and Strang, Addiction 111:1177-1187, 2016). However, we know little about OEND implementation outcomes (i.e., indicators of implementation success), specifically the fidelity of training delivery, and how these may relate to intervention outcomes (i.e., indicators of the success or effectiveness of an intervention), such as overdose knowledge and attitudes. This study evaluated 16 OEND trainings conducted at different Opioid Overdose Prevention Programs in New York City. Trainees (N = 75) completed the Opioid Overdose Knowledge and Attitude Scales before and after training (intervention outcomes). Implementation outcomes were fidelity (competence and adherence of the trainer, N = 10; modified Fidelity Checklist) and acceptability of OEND (Acceptability of Intervention Measure), assessed from multiple perspectives (trainees, trainers, and an independent observer). Trainees' overdose knowledge, t(71) = - 8.12, p < 0.001, 95% CI [- 6.54, - 3.96], and attitudes, t(65) = - 6.85, p < 0.001, 95% CI [- 0.59, - 0.33], improved significantly from pre- to post-training. Stepwise multiple regression models indicated that adherence of the trainer rated from the observer perspective added significantly to the prediction of changes in overdose knowledge, F(1, 67) = 9.81, p = 0.003, and explained 13% of the variance in outcome. However, fidelity measures from the perspective of trainees or trainers and acceptability of OEND were not associated with changes in trainees' overdose knowledge or attitudes. OEND implementation outcomes and their relationship with intervention outcomes differed depending on the role of the fidelity rater in relation to the intervention. Specifically, our findings indicate that fidelity should be measured from an independent perspective (i.e., an individual who is experienced with fidelity rating but not directly involved in the intervention).

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s43477-021-00021-4.

Emotional reactions of trained overdose responders who use opioids following intervention in an overdose event

Background: Our aim was to explore emotional reactions to intervening in an overdose event from the perspective of individuals who use opioids (peer responders). In addition, we were interested in the impact this experience may have on peer responders' feelings about helping in an overdose situation in the future. Methods: For this qualitative sub-study of a randomized controlled trial (RCT), data from 61 interviews were analyzed thematically using an inductive approach. Results: Peer responders had diverse emotional reactions to the overdose event. These ranged from a sense of pride and other positive feelings associated with their ability to help to ambivalence about being involved in situations perceived as challenging and burdensome. There were few reports of the overdose event as an exclusively negative experience. Many peer responders perceived it as their duty to use naloxone again if required. However, some had ambivalent feelings toward this responsibility, which may be related to negative experiences with previous intervention efforts. Conclusions: The capacity of people who use opioids to help reduce the harms associated with opioid overdose is experienced as empowering by some. Nonetheless, engaging peer responders in strategies to reduce opioid-related mortality should be coupled with appropriate resources to process their experiences and emotional responses.

Use of Naloxone in 9-1-1 Patients without Respiratory Depression in Los Angeles County, California (USA)

INTRODUCTION

Along with an increase in opioid deaths, there has been a desire to increase the accessibility of naloxone. However, in the absence of respiratory depression, naloxone is unlikely to be beneficial and may be deleterious if it precipitates withdrawal in individuals with central nervous system (CNS) depression due to non-opioid etiologies.

OBJECTIVE

The aim of this study was to evaluate how effective prehospital providers were in administering naloxone.

METHODS

This is a retrospective study of naloxone administration in two large urban Emergency Medical Service (EMS) systems. The proportion of patients who had a respiratory rate of at least 12 breaths per minute at the time of naloxone administration by prehospital providers was determined.

RESULTS

During the two-year study period, 2,580 patients who received naloxone by prehospital providers were identified. The median (interquartile range) respiratory rate prior to naloxone administration was 12 (6-16) breaths per minute. Using an a priori respiratory rate of under 12 breaths per minute to define respiratory depression, only 1,232 (47.8%; 95% CI, 50.3%-54.2%) subjects who received naloxone by prehospital providers had respiratory depression.

CONCLUSION

This study showed that EMS providers in Los Angeles County, California (USA) frequently administered naloxone to individuals without respiratory depression.

Analisi di Budget Impact della formulazione depot di buprenorfina a rilascio prolungato per la gestione di pazienti affetti da disturbo da uso di oppiacei

Background:

Opioid use disorder (OUD) is a disorder associated with significant rate of morbidity and mortality. Frequent clinic attendance for supervised consumption of sublingual buprenorphine is common. Prolonged-release buprenorphine (PRB) allows a management based on weekly or monthly subcutaneous injections, thus limiting the burdens of clinic attendance and the risks associated with sublingual formulations.

Objective:

To determine the price level of PRB that allows to obtain a neutral impact from the point of view of the economic resources absorbed, in comparison with the alternatives currently available in the Italian context for the management of patients suffering from OUD.

Methods:

The analysis assumes a daily PRB cost of € 8.526 (neutral cost). The analysis aims to determine the economic impact associated with the introduction of PRB in the Italian context for the management of OUD patients. Results are expressed in terms of differential resources absorbed in the alternative scenarios. A one-way sensitivity analysis was also carried out to test the robustness of the results.

Results:

The introduction of PRB implies an increase in the drug acquisition costs over the 5-year time horizon of € 23,016,194.61: such costs are fully compensated by the other cost driver considered in the analysis (drug tests provided, health professionals’ time destined to the provision of the treatment, indirect costs, for savings equal to € 7,255,602.59, € 10,714,320.08 and € 5,046,271.94 respectively) demonstrating its effectiveness in particular by an organizational point of view. Lower price levels for PRB would imply significant savings for the SSN.

Conclusions:

PRB resulted to be associated to a lower level of resources’ absorption in the Italian sector as compared with the available alternatives thus allowing to re-allocate health founds to other fields of the care sector ensuring greater safety for patients and a decreased misuse and diversion rate.

Safety, Efficacy, and Cost of 0.4-mg Versus 2-mg Intranasal Naloxone for Treatment of Prehospital Opioid Overdose

BACKGROUND

Intranasal naloxone is commonly used to treat prehospital opioid overdose. However, the optimal dose is unclear, and currently, no study exists comparing the clinical effect of intranasal naloxone at different doses.

OBJECTIVE

The goal of this investigation was to compare the safety, efficacy, and cost of 0.4- versus 2-mg intranasal naloxone for treatment of prehospital opioid overdose.

METHODS

A retrospective, cross-sectional study was performed of 218 consecutive adult patients receiving intranasal naloxone in 2 neighboring counties in Southeast Michigan: one that used a 0.4-mg protocol and one that used a 2-mg protocol. Primary outcomes were response to initial dose, requirement of additional dosing, and incidence of adverse effects. Unpooled, 2-tailed, 2-sample t-tests and χ² tests for homogeneity were performed with statistical significance defined as P <0.05.

RESULTS

There was no statistically significant difference between the 2 populations in age, mass, gender, proportion of exposures suspected as heroin, response to initial dose, required redosing, or total number of doses by any route. The overall rate of adverse effects was 2.1% under the lower-dose protocol and 29% under the higher-dose protocol (P < 0.001). The lower-dose protocol was 79% less costly.

CONCLUSION AND RELEVANCE

Treatment of prehospital opioid overdose using intranasal naloxone at an initial dose of 0.4 mg was equally effective during the prehospital period as treatment at an initial dose of 2 mg, was associated with a lower rate of adverse effects, and represented a 79% reduction in cost.

Overdoses due to fentanyl and its analogues (F/FAs) push naloxone to the limit

WHAT IS KNOWN AND OBJECTIVE

Food and Drug Administration (FDA) risk evaluation and mitigation strategies (REMs) encourage emergency responders, paramedics, law enforcement agents, and even laypeople to be trained in the administration of naloxone with the intent of rescuing individuals from a known or suspected opioid overdose.

COMMENT

Although naloxone is generally safe and effective at reversing respiratory depression caused by a conventional opioid such as morphine or heroin by competing with the opioid and displacing it from the μ-opioid receptor, questions increasingly are arising as to whether naloxone can adequately reverse opioid overdoses that may involve the potent opioids fentanyl and its analogues (F/FAs). In other words, as more and more opioid overdoses involve F/FAs, can naloxone keep up?

WHAT IS NEW AND CONCLUSION

As a competitive antagonist at μ-opioid receptors, naloxone is often a life-saving agent in cases of overdose caused by conventional opioids, but it may not be versatile or powerful enough to combat the rising tide of overdoses due to fentanyl and its illicit analogues, or in cases of overdose involving combinations of opioids and non-opioids.

The effects of naloxone, diazepam, and quercetin on seizure and sedation in acute on chronic tramadol administration: an experimental study

Background

Tramadol is a widely used synthetic opioid. Substantial research has previously focused on the neurological effects of this drug, while the efficacy of various treatments to reduce the associated side effects has not been well studied. This study aimed to evaluate the protective effects of naloxone, diazepam, and quercetin on tramadol overdose-induced seizure and sedation level in male rats.

Methods

The project was performed with 72 male Wistar rats with an average weight of 200–250 g. The rats were randomly assigned to eight groups. Tramadol was administered intraperitoneally at an initial dose of 25 mg/kg/day. On the 14th day, tramadol was injected at 75 mg/kg, either alone or together with naloxone, diazepam, and quercetin (acute and chronic) individually or in combination. The rats were monitored for 6 h on the last day, and the number, the duration, and the severity of seizures (using the criteria of Racine) were measured over a 6-h observation period. The sedation level was also assessed based on a 4-point criterion, ranging from 0 to 3. Data were analyzed in SPSS software using Kruskal–Wallis, Chi-square, regression analysis, and generalized estimating equation (GEE) tests. The significance level was set at P < 0.05.

Results

The naloxone-diazepam combination reduced the number, severity, and cumulative duration of seizures compared to tramadol use alone and reduced the number of higher-intensity seizures (level 3, 4) to a greater extent than other treatments. Naloxone alone reduced the number and duration of seizures but increased the number of mild seizures (level 2). Diazepam decreased the severity and duration of seizures. However, it increased the number of mild seizures (level 2). In comparison with the tramadol alone group, the acute quercetin group exhibited higher numbers of mild (level 2) and moderate (level 3) seizures. Chronic quercetin administration significantly increased the number of mild seizures. In the GEE model, all groups had higher sedation levels than the saline only group (P < 0.001). None of the protocols had a significant effect on sedation levels compared to the tramadol group.

Conclusion

The combined administration of naloxone and diazepam in acute-on-chronic tramadol poisoning can effectively reduce most seizure variables compared to tramadol use alone. However, none of the treatments improved sedation levels.

Modifying and Evaluating the Opioid Overdose Knowledge Scale for Prescription Opioids: A Pilot Study of the Rx-OOKS

OBJECTIVE

To develop a validated instrument that measures knowledge about prescription opioid overdose.

METHODS

Within an integrated health care system, we adapted, piloted, and tested the reliability and predictive validity of a modified Opioid Overdose Knowledge Scale (OOKS) instrument specific to prescription opioids (Rx-OOKS) with a patient population prescribed long-term opioid therapy and potentially at risk of opioid overdose. We used an interdisciplinary team approach and patient interviews to adapt the instrument. We then piloted the survey on a patient sample and assessed it using Cronbach's alpha and logistic regression.

RESULTS

Rx-OOKS (N = 56) resulted in a three-construct, 25-item instrument. Internal consistency was acceptable for the following constructs: "signs of an overdose" (10 items) at α = 0.851, "action to take with opioid overdose" (seven items) at α = 0.692, and "naloxone use knowledge" (eight items) at α = 0.729. One construct, "risks of an overdose" (three items), had an α of 0.365 and was subsequently eliminated from analysis due to poor performance. We conducted logistic regression to determine if any of the constructs was strongly associated with future naloxone receipt. Higher scores on "actions to take in an overdose" had nine times the odds of receiving naloxone (odds ratio [OR] = 9.00, 95% confidence interval [CI] = 1.42-57.12); higher "naloxone use knowledge" scores were 15.8 times more likely to receive naloxone than those with lower scores (OR = 15.83, 95% CI = 1.68-149.17).

CONCLUSIONS

The Rx-OOKS survey instrument can reliably measure knowledge about prescription opioid overdose recognition and naloxone use. Further, knowledge about actions to take during an opioid overdose and naloxone use were associated with future receipt of naloxone.

Methocinnamox Reverses and Prevents Fentanyl-Induced Ventilatory Depression in Rats

Opioid use disorder affects over 2 million Americans with an increasing number of deaths due to overdose from the synthetic opioid fentanyl and its analogs. The Food and Drug Administration-approved opioid receptor antagonist naloxone (e.g., Narcan) is used currently to treat overdose; however, a short duration of action limits its clinical utility. Methocinnamox (MCAM) is a long-lasting opioid receptor antagonist that may reverse and prevent the ventilatory-depressant effects of fentanyl. This study compared the ability of naloxone (0.0001-10 mg/kg) and MCAM (0.0001-10 mg/kg) to reverse and prevent ventilatory depression by fentanyl and compared the duration of action of MCAM intravenously and subcutaneously in two procedures: ventilation and warm-water tail withdrawal. In male Sprague-Dawley rats (N = 8), fentanyl (0.0032-0.178 mg/kg, i.v.) decreased minute volume in a dose- and time-dependent manner with a dose of 0.178 mg/kg decreasing V_E to less than 40% of control. MCAM and naloxone reversed the ventilatory-depressant effects of 0.178 mg/kg fentanyl in a dose-related manner. The day after antagonist administration, MCAM but not naloxone attenuated the ventilatory-depressant effects of fentanyl. The duration of action of MCAM lasted up to 3 days and at least 2 weeks after intravenous and subcutaneous administration, respectively. MCAM attenuated the antinociceptive effects of fentanyl, with antagonism lasting up to 5 days and more than 2 weeks after intravenous and subcutaneous administration, respectively. Reversal and prolonged antagonism by MCAM might provide an effective treatment option for the opioid crisis, particularly toxicity from fentanyl and related highly potent analogs. SIGNIFICANCE STATEMENT: This study demonstrates that like naloxone, methocinnamox (MCAM) reverses the ventilatory-depressant effects of fentanyl in a time- and dose-related manner. However, unlike naloxone, the duration of action of MCAM was greater than 2 weeks when administered subcutaneously and up to 5 days when administered intravenously. These data suggest that MCAM might be particularly useful for rescuing individuals from opioid overdose, including fentanyl overdose, as well as protecting against the reemergence of ventilatory depression (renarconization).

Analgesic opioid use disorders in patients with chronic non-cancer pain: A holistic approach for tailored management

Chronic pain is a major public health issue that frequently leads to analgesic opioid prescriptions. These prescriptions could cause addiction issues in high-risk patients with associated comorbidities, especially those of a psychiatric, addictive, and social nature. Pain management in dependent patients is complex and is yet to be established. By combining the views of professionals from various specialties, we conducted an integrative review on this scope. This methodology synthesizes knowledge and results of significant practical studies to provide a narrative overview of the literature. The main results consisted in first proposing definitions that could allow shared vocabulary among health professionals regardless of their specialties. Next, a discussion was conducted around the main strategies for managing prescription opioid dependence, as well as pain in the context of opioid dependence and associated comorbidities. As a conclusion, we proposed to define the contours of holistic management by outlining the main guidelines for creating a multidisciplinary care framework for multi-comorbid patients with chronic pathologies.

Stakeholders' Perceptions of Factors Influencing the Use of Take-Home-Naloxone

Background and Aims: Opioid associated death and overdose is a growing burden in societies all over the world. In recent years, legislative changes have increased access to naloxone in the take-home setting for use by patients with a substance use disorder and bystanders, to prevent opioid overdose deaths. However, few studies have explored the factors influencing the uptake by its multiple stakeholders. The aim of this scoping review was to explore the factors influencing the use of take-home naloxone from the perspectives of different stakeholders. Methods: A scoping review methodology was adopted with a systematic search of databases EMBASE, MEDLINE and PubMed. A variation of the search words “naloxone”, “opioid” and “overdose” were used in each database. The articles were screened according to the predetermined inclusion/exclusion criteria and categorized based on their key perspective or target population. Results: The initial database search yielded a total of 1483 articles. After a series of screening processes, 51 articles were included for analysis. Two key stakeholder perspectives emerged: patients and bystanders (n = 36), and healthcare professionals (n = 15). Within the patient and bystander group, a strong consensus arose that there were positive outcomes from increased access to take-home naloxone and relevant training programs. Despite these positive outcomes, some healthcare professionals were concerned that take-home naloxone would encourage high-risk opioid use. Conclusion: Take-home naloxone is slowly being introduced into community practice, with a sense of enthusiasm from patients and bystanders. There are still a number of barriers that need to be addressed from healthcare professionals’ perspective. Future research should be aimed at emergency care professionals outside of the US, who are most experienced with naloxone and its potential impact on the community.

Model and approach for assessing implementation context and fidelity in the HEALing Communities Study

BACKGROUND

In response to the U.S. opioid epidemic, the HEALing (Helping to End Addiction Long-term^SM) Communities Study (HCS) is a multisite, wait-listed, community-level cluster-randomized trial that aims to test the novel Communities That HEAL (CTH) intervention, in 67 communities. CTH will expand an integrated set of evidence-based practices (EBPs) across health care, behavioral health, justice, and other community-based settings to reduce opioid overdose deaths. We present the rationale for and adaptation of the RE-AIM/PRISM framework and methodological approach used to capture the CTH implementation context and to evaluate implementation fidelity.

METHODS

HCS measures key domains of the internal and external CTH implementation context with repeated annual surveys and qualitative interviews with community coalition members and key stakeholders. Core constructs of fidelity include dosage, adherence, quality, and program differentiation-the adaptation of the CTH intervention to fit each community's needs. Fidelity measures include a monthly CTH checklist, collation of artifacts produced during CTH activities, coalition and workgroup attendance, and coalition meeting minutes. Training and technical assistance delivered by the research sites to the communities are tracked monthly.

DISCUSSION

To help attenuate the nation's opioid epidemic, the adoption of EBPs must be increased in communities. The HCS represents one of the largest and most complex implementation research experiments yet conducted. Our systematic examination of implementation context and fidelity will significantly advance understanding of how to best evaluate community-level implementation of EBPs and assess relations among implementation context, fidelity, and intervention impact.

Evaluation of Injectable Naloxone-Releasing Hydrogels

The opioid epidemic in the United States is a serious public health crisis affecting over 1.7 million Americans. In the last two decades, almost 450 000 people have died from an opioid overdose, with nearly 20% of these deaths occurring in 2017 and 2018 alone. During an overdose, overstimulation of the μ-opioid receptor leads to severe and potentially fatal respiratory depression. Naloxone is a competitive μ-opioid-receptor antagonist that is widely used to displace opioids and rescue from an overdose. Here, we describe the development of a slow-release, subcutaneous naloxone formulation for potential management of opioid overdose, chronic pain, and opioid-induced constipation. Naloxone is loaded into self-assembling peptide hydrogels for controlled drug release. The mechanical, chemical, and structural properties of the nanofibrous hydrogel enable subcutaneous administration and slow, diffusion-based release kinetics of naloxone over 30 days in vitro. The naloxone hydrogel scaffold showed cytocompatibility and did not alter the β-sheet secondary structure or thixotropic properties characteristic of self-assembling peptide hydrogels. Our results show that this biocompatible and injectable self-assembling peptide hydrogel may be useful as a vehicle for tunable, sustained release of therapeutic naloxone. This therapy may be particularly suited for preventing renarcotization in patients who refuse additional medical assistance following an overdose.

Adult Basic Life Support: International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Adult Basic Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This2020 International Consensus on Cardiopulmonary Resuscitation(CPR)and Emergency Cardiovascular Care Science With Treatment Recommendationson basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Opioid overdose reversals using naloxone in New York City by people who use opioids: Implications for public health and overdose harm reduction approaches from a qualitative study

BACKGROUND

Adverse reactions to naloxone, such as withdrawal symptoms and aggression, are widely recognised in the literature by pharmaceutical manufacturers and clinical practitioners as standard reactions of individuals who are physically dependent upon opioid drugs following the reversal of potentially fatal opioid overdose. This paper seeks to provide a differentiated view on reactions to naloxone that may have important implications for public health and harm reduction approaches.

METHODS

Analyses from a qualitative investigation embedded within a 5-year Randomised Controlled Trial (RCT) examined the risks and benefits of Overdose Education and Naloxone Distribution (OEND) training models (brief or extended training) in various populations of people who use opioids in New York City. The qualitative experiences (obtained through semi-structured interviews) of 46 people who use opioids and who were each involved in the delivery of naloxone, during 56 separate overdose events that occurred throughout 2016-2018, were studied. Situational analysis and inductive content analysis of interview data focused upon overdose reversals in an attempt to provide understandings of the various adverse effects associated with naloxone from their perspective. These analyses were supplemented by data sessions within the research team during which the findings obtained from situational analysis and inductive content analysis were reviewed and complemented by deductive (clinical) appraisals of the various physical and psychological effects associated with the overdose reversals.

RESULTS

People who use opioids recognise three distinct and interconnected outcomes that may follow a successful opioid overdose reversal after intramuscular or intranasal administration of naloxone. These outcomes are here termed, (i) 'rage' (describing a wide range of angry, hostile and/or aggressive outbursts), (ii) 'withdrawal symptoms,' and (iii) 'not rage, not withdrawal' (i.e., a wide range of short-lived, 'harmless' conditions (such as temporary amnesia, mild emotional outbursts, or physical discomfort) that do not include rage or withdrawal symptoms).

CONCLUSION

Physical and psychological reactions to naloxone should not be understood exclusively as a consequence of acute, opioid-related, withdrawal symptoms. The three distinct and interconnected reversal outcomes identified in this study are considered from a harm reduction policy perspective and are further framed by concepts associated with 'mediated toxicity' (i.e., harm triggered by medicine). The overall conclusion is that harm reduction training programmes that are aligned to the policy and practice of take home naloxone may be strengthened by including awareness and training in how to best respond to 'rage' associated with overdose reversal following naloxone administration by people who use opioids and other laypersons.

Opportunities for Emergency Medical Services Intervention to Prevent Opioid Overdose Mortality

OBJECTIVES

The opioid crisis is a growing cause of mortality in the United States and may be mitigated by innovative approaches to identifying individuals at-risk of fatal opioid overdose. We examined Emergency Medical Services (EMS) utilization among a cohort of individuals who died from opioid overdose in order to identify potential opportunities for intervention. Methods: Individuals who died of unintentional opioid overdose in a large North Carolina county between 01/01/2014 and 12/31/2016 were studied in a retrospective cohort. Death records obtained from North Carolina Vital Records were linked to EMS patient care records obtained from the county EMS System in order to describe the EMS encounters of each decedent in the year preceding their death. Patient demographics and EMS encounters were assessed to identify encounter characteristics that may be targeted for intervention. Chi-square tests and odds ratios were used to evaluate and characterize the statistical significance of differences in EMS utilization. Results: Of the 218 individuals who died from unintentional opioid overdose in the study interval, 30% (n = 66) utilized EMS in the year before their death and 17% (n = 38) had at least one EMS encounter with documented drug or alcohol use (i.e. "drug-related encounter"). The mean age at death was 38 (range 19-74) years, 30% were female, 89% were White, and 8% were Black/African American. Factors associated with higher incidence of EMS utilization included age (P<.001), gender (P=.006), and race (P<.001). Decedents aged 56-65 had the highest EMS utilization (47%) and patients aged <25 and 25-35 had more drug-related EMS encounters (29% and 20%, respectively). The most common reasons for EMS utilization were "other medical" (27%), "non-traumatic pain" (20%), "traumatic injury" (16%), and "poisoning/drug ingestion" (14%). Drug or alcohol use was documented by EMS in 33% of all encounters and an opioid prescription was reported in 22% of encounters. Conclusions: Nearly one-third of individuals who died from accidental opioid overdose utilized EMS in the year before their death and nearly one-fifth had a drug-related encounter. EMS encounters may present an opportunity to identify individuals at-risk of opioid overdose and, ultimately, reduce overdose mortality.

A descriptive study of racial and ethnic differences of drug overdoses and naloxone administration in Pennsylvania

INTRODUCTION

Drug overdose is a significant public health problem, yet little is known about racial/ethnic differences in drug overdose rates and/or in responses to a drug overdose following naloxone administration. This paper examines differences in rates of survivorship, response, revival and administration of naloxone by race and ethnicity among those who experienced a drug overdose in Pennsylvania between January 1, 2018 and December 31, 2019. Spatio-temporal variations in drug overdose locations were examined to facilitate understanding of service development, planning, and delivery of effective treatment need.

METHODS

Ten thousand two hundred and ninety drug overdose incidents were analyzed from the Pennsylvania Overdose Information Network (ODIN). The ODIN is a centralized repository that contains information on drug overdoses victims including age, gender and race/ethnicity, naloxone administrations and survivorship, drug(s) suspected of causing the overdose, victim outcomes (e.g. hospitalizations and arrests) and average naloxone dosage per victim. Between group differences were tested using χ2 -tests of independence. Multivariate logistic regression was used to estimate the predicted probability of survivorship according to victim characteristics. All statistical analyses and mapping were performed using the R statistical programming environment.

RESULTS

About eighty-seven percent of drug overdose response victims were white, and seventy-one percent were between the ages of 20-39. White females were more likely to receive an overdose response compared to black or Hispanic females. A non-opioid was indicated more frequently in overdoses involving black victims compared to either whites or Latinos. Latinos and blacks were more likely to survive a drug overdose. However, following naloxone administration, no racial or ethnic differences in survivorship were noted. Differences in responsiveness to naloxone and transitions to care following the drug overdose event were also found. Finally, overdoses among Blacks and Latinos demonstrated a stronger spatial patterning across counties compared to whites.

CONCLUSIONS

This study found a significant, disparate impact of race/ethnicity on fatal drug overdoses when naloxone is not administered. Further, individuals who were administered naloxone and subsequently received medical care in a hospital experienced lower drug-related mortality, suggesting that first responders are critical intervention points for individuals in need of medical treatment following a drug overdose. However, while naloxone administration is a necessary first step in the recovery process, longitudinal pathways towards treatment are critical to stem the drug overdose crisis.

Comparison of the efficacy of an infusion pump or standard IV push injection to deliver naloxone in treatment of opioid toxicity

Background:

The optimal goal of naloxone infusion in intensive care units is to ameliorate opioid-induced side effects in therapy or eliminate the symptoms of opioid toxicity in overdoses. Accurately monitoring and regulating the doses is critical to prevent adverse effects related to naloxone administration. The present study aimed to compare treatment outcomes when using two methods of intravenous naloxone infusion: an infusion pump or the standard method.

Methods:

This study involved 80 patients with signs and symptoms of opioid overdose. The patients were randomly assigned into two groups with respect to intravenous infusion of naloxone by either an infusion pump or the standard method.

Results:

Comparison of study parameters between the two groups at 12 and 24 hours after intervention showed significantly more compensatory acid-base imbalance in the naloxone infusion pump group. In the group that received naloxone by pump, only one patient experienced withdrawal symptoms, but withdrawal symptoms appeared in 12 patients (30.0%) in the standard intravenous infusion group within 12 hours and in seven additional patients (17.5%) within 24 hours of intervention. In the group receiving pump-based naloxone infusion therapy, no another complications were reported; however in the standard infusion group, the 12-hour and 24-hour complication rates were 55.0% and 32.5%, respectively. The length of hospital stay was 2.85±1.05 and 4.22±0.92 days for the pump and standard infusion groups, respectively (P<0.001).

Conclusions:

Naloxone infusion using an infusion pump may be safer with regard to hemodynamic stability, resulting in shorter hospitalization periods, and fewer posttreatment complications.

Regional and temporal effects of naloxone access laws on opioid overdose mortality

BACKGROUND

Naloxone is a drug that reverses opioid overdose. Naloxone Access Laws (NALs) increase public access to naloxone and have been considered as one promising solution to reducing opioid-related harm. However, previous studies on whether NALs are effective in reducing opioid overdose mortality found somewhat contradictory results. Our study attempts to provide a more definitive answer to this question by utilizing an approach that matches NAL vs non-NAL states and stratifies by US region and years of implementation. Methods: We assess the causal impact of NALs on state-level opioid-related mortality rate by constructing a comparison group using matching to produce a valid counterfactual scenario, and estimating the effects of NAL using a semi-dynamic staggered difference in differences (DID) model that allows heterogeneous effects across regions and years of implementation. State-level opioid-related mortality data from CDC's WONDER database and NALs effective from 1999 to 2014 were utilized. Results: We find that NAL effects have reduced fatal opioid-related overdose in western states and have produced minimal or no effects for other regions. Conclusions: The effects of NALs vary across regions and years of implementation. It is important to study the successful experience of the western states.