Evaluation of adjunctive ketamine to benzodiazepines for management of alcohol withdrawal syndrome

Epigenetic drugs and psychedelics as emerging therapies for alcohol use disorder: insights from preclinical studies

Alcohol use disorder (AUD) is a public health issue that affects millions of people worldwide leading to physical, mental and socio-economic consequences. While current treatments for AUD have provided relief to individuals, their effectiveness on the long term is often limited, leaving a number of affected individuals without sustainable solutions. In this review, we aim to explore two emerging approaches for AUD: psychedelics and epigenetic drugs (i.e., epidrugs). By examining preclinical studies, different animal species and procedures, we delve into the potential benefits of each of these treatments in terms of addictive behaviors (alcohol drinking and seeking, motivation to drink alcohol and prevention of relapse). Because psychedelics and epidrugs may share common and complementary mechanisms of action, there is an exciting opportunity for exploring synergies between these approaches and their parallel effectiveness in treating AUD and the diverse associated psychiatric conditions.

Ketamine in Critically Ill Patients: Use, Perceptions, and Potential Barriers

Objective: To evaluate practitioner use of ketamine and identify potential barriers to use in acutely and critically ill patients. To compare characteristics, beliefs, and practices of ketamine frequent users and non-users. Methods: An online survey developed by members of the Society of Critical Care Medicine (SCCM) Clinical Pharmacy and Pharmacology Section was distributed to physician, pharmacist, nurse practitioner, physician assistant and nurse members of SCCM. The online survey queried SCCM members on self-reported practices regarding ketamine use and potential barriers in acute and critically ill patients. Results: Respondents, 341 analyzed, were mostly adult physicians, practicing in the United States at academic medical centers. Clinicians were comfortable or very comfortable using ketamine to facilitate intubation (80.0%), for analgesia (77.9%), procedural sedation (79.4%), continuous ICU sedation (65.8%), dressing changes (62.4%), or for asthma exacerbation and status epilepticus (58.8% and 40.4%). Clinicians were least comfortable with ketamine use for alcohol withdrawal and opioid detoxification (24.7% and 23.2%). Most respondents reported "never" or "infrequently" using ketamine preferentially for continuous IV analgesia (55.6%) or sedation (61%). Responses were mixed across dosing ranges and duration. The most common barriers to ketamine use were adverse effects (42.6%), other practitioners not routinely using the medication (41.5%), lack of evidence (33.5%), lack of familiarity (33.1%), and hospital/institutional policy guiding the indication for use (32.3%). Conclusion: Although most critical care practitioners report feeling comfortable using ketamine, there are many inconsistencies in practice regarding dose, duration, and reasons to avoid or limit ketamine use. Further educational tools may be targeted at practitioners to improve appropriate ketamine use.

Substitution therapy for patients with alcohol dependence: Mechanisms of action and efficacy

New approaches for the treatment of alcohol dependence (AD) may improve patient outcomes. Substitution maintenance therapy is one of the most effective treatment options for opioid and nicotine use disorders. So far, there has been little attention to substitution therapy for the treatment of AD. Here, we explain the mechanistic foundations of alcohol substitution maintenance therapy. Alcohol has many primary targets in the brain (and other organs) and the physical interaction of ethanol molecules with these specific ethanol-sensitive sites on a variety of ionotropic receptors (e.g. GABA-A, NMDA, and nicotinic acetylcholine (nACh) receptors) and ion channels provides the rationale for substitution. As such, a variety of compounds can interact with those ethanol-sensitive sites and can thus substitute for some of the effects of alcohol. For some of these compounds, alcohol discrimination studies have shown their substitution potential. Accordingly, potential substitution treatments include agonists acting at GABA receptors such as sodium oxybate, baclofen and benzodiazepines, NMDA receptor antagonists such as ketamine and memantine, or nAChRs agonists such as varenicline. All these compounds are already approved for other indications and we present clinical evidence for these drugs in the treatment of alcohol withdrawal syndrome (AWS) and in the long-term treatment of AD, and outline future steps for their acceptance as substitution treatment in AD. Finally, we discuss the substitution approach of managed alcohol programs for the most severely affected homeless populations. Results showed that sodium oxybate is probably the closest to a substitution therapy for AD and is already approved for the treatment of AWS and in the long-term treatment of AD in some countries. In conclusion, we argue that better AD treatment can be provided if substitution maintenance treatments for alcohol are implemented at a similar scale as for opioid and nicotine use disorder.

The SLC6A15-SLC6A20 Neutral Amino Acid Transporter Subfamily: Functions, Diseases, and Their Therapeutic Relevance

The neutral amino acid transporter subfamily that consists of six members, consecutively SLC6A15-SLC620, also called orphan transporters, represents membrane, sodium-dependent symporter proteins that belong to the family of solute carrier 6 (SLC6). Primarily, they mediate the transport of neutral amino acids from the extracellular milieu toward cell or storage vesicles utilizing an electric membrane potential as the driving force. Orphan transporters are widely distributed throughout the body, covering many systems; for instance, the central nervous, renal, or intestinal system, supplying cells into molecules used in biochemical, signaling, and building pathways afterward. They are responsible for intestinal absorption and renal reabsorption of amino acids. In the central nervous system, orphan transporters constitute a significant medium for the provision of neurotransmitter precursors. Diseases related with aforementioned transporters highlight their significance; SLC6A19 mutations are associated with metabolic Hartnup disorder, whereas altered expression of SLC6A15 has been associated with a depression/stress-related disorders. Mutations of SLC6A18-SLCA20 cause iminoglycinuria and/or hyperglycinuria. SLC6A18-SLC6A20 to reach the cellular membrane require an ancillary unit ACE2 that is a molecular target for the spike protein of the SARS-CoV-2 virus. SLC6A19 has been proposed as a molecular target for the treatment of metabolic disorders resembling gastric surgery bypass. Inhibition of SLC6A15 appears to have a promising outcome in the treatment of psychiatric disorders. SLC6A19 and SLC6A20 have been suggested as potential targets in the treatment of COVID-19. In this review, we gathered recent advances on orphan transporters, their structure, functions, related disorders, and diseases, and in particular their relevance as therapeutic targets. SIGNIFICANCE STATEMENT: The following review systematizes current knowledge about the SLC6A15-SLCA20 neutral amino acid transporter subfamily and their therapeutic relevance in the treatment of different diseases.

[Interest and mechanisms of action of ketamine in alcohol addiction- A review of clinical and preclinical studies]

Alcohol Use Disorder (AUD) is a psychiatric condition characterized by chronic and excessive drinking despite negative consequences on overall health and social or occupational functioning. There are currently limited treatment options available for AUD, and the effects size and the response rates to these treatments are often low to moderate. The World Health Organization has identified the development of medications to treat AUD as one of its 24 priorities. This past decade was marked by a renewed interest in psychedelic use in psychiatry. At the centre of this renaissance, ketamine, an atypical psychedelic already used in the treatment of major depression, is an NMDA receptor antagonist that exists as a racemic compound made of two enantiomers, S-ketamine, and R-ketamine. Each form can be metabolized into different metabolites, some of which having antidepressant properties. In this article, we review both clinical and preclinical studies on ketamine and its metabolites in the treatment of AUD. Preclinical as well as clinical studies have revealed that ketamine is effective in reducing withdrawal symptoms and alcohol craving. Convergent data showed that antidepressant properties of ketamine largely contribute to the decreased likelihood of alcohol relapse, especially in patients undergoing ketamine-assisted psychotherapies. Its effectiveness is believed to be linked with its ability to regulate the glutamatergic pathway, enhance neuroplasticity, rewire brain resting state network functional connectivity and decrease depressive-like states. However, it remains to further investigate (i) why strong differences exist between male and female responses in preclinical studies and (ii) the respective roles of each of the metabolites in the ketamine effects in both genders. Interestingly, current studies are also focusing on ketamine addiction and the comorbidity between alcohol addiction and depression occurring more frequently in females.

Ketamine Treatment for Alcohol Use Disorder: A Systematic Review

Alcohol use disorder (AUD) is a chronic, recurrent condition that demonstrates significant heterogeneity in treatment response to first-line agents. Ketamine may have a therapeutic role in substance use disorders; however, research on this topic is limited. The objective of this systematic review is to qualitatively synthesize the current evidence of ketamine treatment for alcohol use disorder and evaluate its efficacy. A systematic review of Medline, PsycINFO, CINAHL, the Cochrane Library, and Google Scholar was performed to identify completed human studies in English or Spanish (from inception to July 2022) that assess the effectiveness of ketamine therapy for alcohol use disorder. This review was registered on the Open Science Framework. Data were descriptively summarized and presented in tables and tested via narrative synthesis methodology. The risk of bias was measured with Cochrane Collaboration tools and a case series quality assessment tool. A total of 11 studies with 854 adult patients in three different countries (the USA, the UK, and Russia) were analyzed. Sample sizes ranged from 5 to 211 people. Seven studies included patients with alcohol use disorder, one study focused on heavy drinkers, and three studies elaborated extensively on alcohol withdrawal. The overall proportion of patients achieving abstinence and reduced consumption was most favorable in people receiving combination ketamine and psychotherapy treatment. The results were mixed with respect to relapse, craving, and withdrawal. Ketamine may be an effective therapeutic modality for people with alcohol use disorders who fail to respond to FDA-approved first-line agents. More robust clinical trials are necessary to provide a more accurate assessment of efficacy, safety profile, and dosing strategies for ketamine utilization in alcohol use disorder.

The Treatment of Substance Use Disorders: Recent Developments and New Perspectives

Substance-related disorders are complex psychiatric disorders that are characterized by continued consumption in spite of harmful consequences. Addiction affects various brain networks critically involved in learning, reward, and motivation, as well as inhibitory control. Currently applied therapeutic approaches aim at modification of behavior that ultimately leads to decrease of consumption or abstinence in individuals with substance use disorders. However, traditional treatment methods might benefit from recent neurobiological and cognitive neuroscientific research findings. Novel cognitive-behavioral approaches in the treatment of addictive behavior aim at enhancement of strategies to cope with stressful conditions as well as craving-inducing cues and target erroneous learning mechanisms, including cognitive bias modification, reconsolidation-based interventions, mindfulness-based interventions, virtual-reality-based cue exposure therapy as well as pharmacological augmentation strategies. This review discusses therapeutic strategies that target dysregulated neurocognitive processes associated with the development and maintenance of disordered substance use and may hold promise as effective treatments for substance-related disorders.

Ketamine and esketamine for crisis management in patients with depression: Why, whom, and how?

Currently, only a limited number of interventions can rapidly relieve depressive symptomatology in patients with major depressive disorder or bipolar disorder experiencing extreme distress. Such crises, especially when suicide attempt or ideation is involved, are a major risk factor of suicide. Ketamine, a N-methyl-d-aspartate glutamate receptor antagonist, and its enantiomer esketamine rapidly reduce depressive symptoms in depressed patients with current suicidal ideation. Recently, esketamine has been approved for use in patients with depression at risk of suicide and for psychiatric emergency by major medical agencies in the United States and Europe, whereas ketamine is increasingly used off-label. However, there is currently limited guidance on why, when, and how to use these drugs in patients with depression to treat a crisis. In this review article, we provide a succinct overview of the cellular and molecular mechanisms of action of ketamine and esketamine, and of the functional brain changes following their administration. We also summarize the major clinical studies on ketamine and esketamine efficacy in patients experiencing a crisis (generally, suicidal ideation), and propose a profile of patients who can benefit most from such drugs, on the basis of neurobiological and clinical observations. Finally, we describe the administration mode, the efficacy and tolerability profiles, the side effect management, possible concomitant treatments and the issue of deprescribing.

Ketamine use in critically ill patients: a narrative review

Ketamine is unique among anesthetics and analgesics. The drug is a rapid-acting general anesthetic that produces an anesthetic state characterized by profound analgesia, preserved pharyngeal-laryngeal reflexes, normal or slightly enhanced skeletal muscle tone, cardiovascular and respiratory stimulation, and occasionally a transient and minimal respiratory depression. Research has demonstrated the efficacy of its use on anesthesia, pain, palliative care, and intensive care. Recently, it has been used for postoperative and chronic pain, as an adjunct in psychotherapy, as a treatment for depression and posttraumatic stress disorder, as a procedural sedative, and as a treatment for respiratory and/or neurologic clinical conditions. Despite being a safe and widely used drug, many physicians, such as intensivists and those practicing in emergency care, are not aware of the current clinical applications of ketamine. The objective of this narrative literature review is to present the theoretical and practical aspects of clinical applications of ketamine in intensive care unit and emergency department settings.

Ketamine for the treatment of mental health and substance use disorders: comprehensive systematic review

BACKGROUND

In the past two decades, subanaesthetic doses of ketamine have been demonstrated to have rapid and sustained antidepressant effects, and accumulating research has demonstrated ketamine's therapeutic effects for a range of psychiatric conditions.

AIMS

In light of these findings surrounding ketamine's psychotherapeutic potential, we systematically review the extant evidence on ketamine's effects in treating mental health disorders.

METHOD

The systematic review protocol was registered in PROSPERO (identifier CRD42019130636). Human studies investigating the therapeutic effects of ketamine in the treatment of mental health disorders were included. Because of the extensive research in depression, bipolar disorder and suicidal ideation, only systematic reviews and meta-analyses were included. We searched Medline and PsycINFO on 21 October 2020. Risk-of-bias analysis was assessed with the Cochrane Risk of Bias tools and A Measurement Tool to Assess Systematic Reviews (AMSTAR) Checklist.

RESULTS

We included 83 published reports in the final review: 33 systematic reviews, 29 randomised controlled trials, two randomised trials without placebo, three non-randomised trials with controls, six open-label trials and ten retrospective reviews. The results were presented via narrative synthesis.

CONCLUSIONS

Systematic reviews and meta-analyses provide support for robust, rapid and transient antidepressant and anti-suicidal effects of ketamine. Evidence for other indications is less robust, but suggests similarly positive and short-lived effects. The conclusions should be interpreted with caution because of the high risk of bias of included studies. Optimal dosing, modes of administration and the most effective forms of adjunctive psychotherapeutic support should be examined further.

Therapeutic Potentials of Ketamine and Esketamine in Obsessive-Compulsive Disorder (OCD), Substance Use Disorders (SUD) and Eating Disorders (ED): A Review of the Current Literature

The obsessive–compulsive spectrum refers to disorders drawn from several diagnostic categories that share core features related to obsessive–compulsive disorder (OCD), such as obsessive thoughts, compulsive behaviors and anxiety. Disorders that include these features can be grouped according to the focus of the symptoms, e.g., bodily preoccupation (i.e., eating disorders, ED) or impulse control (i.e., substance use disorders, SUD), and they exhibit intriguing similarities in phenomenology, etiology, pathophysiology, patient characteristics and clinical outcomes. The non-competitive N-methyl-D-aspartate receptor (NMDAr) antagonist ketamine has been indicated to produce remarkable results in patients with treatment-resistant depression, post-traumatic stress disorder and OCD in dozens of small studies accrued over the past decade, and it appears to be promising in the treatment of SUD and ED. However, despite many small studies, solid evidence for the benefits of its use in the treatment of OCD spectrum and addiction is still lacking. Thus, the aim of this perspective article is to examine the potential for ketamine and esketamine in treating OCD, ED and SUD, which all involve recurring and intrusive thoughts and generate associated compulsive behavior. A comprehensive and updated overview of the literature regarding the pharmacological mechanisms of action of both ketamine and esketamine, as well as their therapeutic advantages over current treatments, are provided in this paper. An electronic search was performed, including all papers published up to April 2021, using the following keywords (“ketamine” or “esketamine”) AND (“obsessive” OR “compulsive” OR “OCD” OR “SUD” OR “substance use disorder” OR “addiction” OR “craving” OR “eating” OR “anorexia”) NOT review NOT animal NOT “in vitro”, on the PubMed, Cochrane Library and Web of Science online databases. The review was conducted in accordance with preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The use and efficacy of ketamine in SUD, ED and OCD is supported by glutamatergic neurotransmission dysregulation, which plays an important role in these conditions. Ketamine’s use is increasing, and preliminary data are optimistic. Further studies are needed in order to better clarify the many unknowns related to the use of both ketamine and esketamine in SUD, ED and OCD, and to understand their long-term effectiveness.

The Reemergence of Ketamine for Treatment in Critically Ill Adults

OBJECTIVES

To assess the evidence and discuss the risks and clinical relevance of ketamine for the treatment of various disease states impacting the adult critically ill population.

DATA SOURCES

A literature review was performed using PubMed evaluating primary literature published until August 2018.

STUDY SELECTION

Case reports, observational studies (cohort, case-control), and randomized controlled trials involving patients 18 years and older in a nonperioperative setting using either IV or intramuscular ketamine were included for analysis. Uses of ketamine discussed focused on critically ill patients in the ICU and emergency department settings.

DATA EXTRACTION

Included studies were evaluated for dosing, outcomes, and adverse effects of ketamine. For each study, the design, population, intervention, investigated outcomes, and results were assessed.

DATA SYNTHESIS

The evidence was organized according to use of ketamine, which included pain, sedation, status asthmaticus, alcohol withdrawal syndrome, status epilepticus, and acute behavioral psychologic disturbances. Evaluation of the evidence was based on the included primary literature along with any related guideline recommendations.

CONCLUSIONS

Ketamine has suggested potential benefit in several disease states impacting critically ill patients including pain, alcohol withdrawal syndrome, status epilepticus, and acute agitation. Further supporting evidence is needed to validate its use in the setting of critical illness.

Comeback of ketamine: resurfacing facts and dispelling myths

Initially known as CI-581, ketamine was first synthesized in 1962 as a replacement from phencyclidine. It has since been used as an anesthetic and analgesic. In addition, it has bronchodilating, sedative, and amnestic properties, preserving airway reflexes and sympathetic nervous system tone. Since the discovery of ketamine, it has been a major topic of discussion due to controversies regarding its usage in particular sets of patients. In the past 50 years, despite its potential benefits, it is not commonly used because of concerns of "emergence phenomenon," its use as a substance of abuse, and its systemic side effects. Since 2012, three World Health Organization reviews on ketamine have addressed its international control. Researchers have been studying this wonder drug for a decade worldwide. Many myths of ketamine regarding emergence phenomenon and its use in traumatic brain injury and open eye injury have been disproved in recent times. It is becoming popular in pre-hospital settings, critical care, emergency medicine, low-dose acute pain services, and adjuvant in regional anesthesia techniques. This review highlights the current consensus on the various applications of ketamine in the literature.

Principles of Pharmacotherapy of Seizures and Status Epilepticus

Status epilepticus is a neurological emergency with an outcome that is highly associated with the initial pharmacotherapy management that must be administered in a timely fashion. Beyond first-line therapy of status epilepticus, treatment is not guided by robust evidence. Optimal pharmacotherapy selection for individual patients is essential in the management of seizures and status epilepticus with careful evaluation of pharmacokinetic and pharmacodynamic factors. With the addition of newer antiseizure agents to the market, understanding their role in the management of status epilepticus is critical. Etiology-guided therapy should be considered in certain patients with drug-induced seizures, alcohol withdrawal, or autoimmune encephalitis. Some patient populations warrant special consideration, such as pediatric, pregnant, elderly, and the critically ill. Seizure prophylaxis is indicated in select patients with acute neurological injury and should be limited to the acute postinjury period.

Alcohol Withdrawal Syndrome in Neurocritical Care Unit: Assessment and Treatment Challenges

Alcohol withdrawal syndrome (AWS) can range from mild jittery movements, nausea, sweating to more severe symptoms such as seizure and death. Severe AWS can worsen cognitive function, increase hospital length of stay, and in-hospital mortality and morbidity. Due to a lack of reliable history of present illness in many patients with neurological injury as well as similarities in clinical presentation of AWS and some commonly encountered neurological syndromes, the true incidence of AWS in neurocritical care patients remains unknown. This review discusses challenges in the assessment and treatment of AWS in patients with neurological injury, including the utility of different scoring systems such as the Clinical Institute Withdrawal Assessment and the Minnesota Detoxification Scale as well as the reliability of admission alcohol levels in predicting AWS. Treatment strategies such as symptom-based versus fixed dose benzodiazepine therapy and alternative agents such as baclofen, carbamazepine, dexmedetomidine, gabapentin, phenobarbital, ketamine, propofol, and valproic acid are also discussed. Finally, a treatment algorithm considering the neurocritical care patient is proposed to help guide therapy in this setting.

Front-loaded diazepam versus lorazepam for treatment of alcohol withdrawal agitated delirium

BACKGROUND

Front-loaded diazepam is used to rapidly control agitation in patients with severe alcohol withdrawal syndrome (AWS). Our institution began using front-loaded lorazepam in August 2017 secondary to a nation-wide shortage of intravenous (IV) diazepam. Currently, there are no studies comparing lorazepam to diazepam for frontloading in severe AWS.

METHOD

Retrospective cohort study of all adults presenting to the emergency department with a diagnosis of AWS and prescribed the institution's alcohol withdrawal agitated delirium protocol 8 months pre and post shortage of IV diazepam were eligible inclusion for the study. Of these, 106 patients were front-loaded with diazepam and 70 patients were front-loaded with lorazepam.

RESULTS

There was no difference in the mean change in Clinical Institute Withdrawal Assessment of Alcohol Scale, Revised scores 24 h pre and post front-loading in the two groups (-13.9 ± -8.08 vs. -13.1 ± -8.91, p = 0.534). Patients who received front-loaded lorazepam had an increased incidence of ICU-delirium (positive for the Confusion Assessment Method in the ICU: 75% with lorazepam vs. 52.6% with diazepam, p = 0.009) and a higher risk of over-sedation, but this did not reach statistical significance (Richmond Agitation-Sedation Scale score < -1: 32.1% with lorazepam vs. 18.2% with diazepam, p = 0.063).

CONCLUSION

Front-loaded lorazepam was similar to front-loaded diazepam in controlling AWS symptoms. Lorazepam's delayed onset of action should be considered when determining how quickly repeat doses are administered to avoid the potential for adverse drug events.

Pharmacotherapeutic management of acute alcohol withdrawal syndrome in critically Ill patients

INTRODUCTION

Alcohol withdrawal syndrome is a common and life-threatening condition in patients suffering from alcohol use disorder. Treatment of this syndrome is challenging, especially in patients that are critically ill, either because of withdrawal symptoms or underlying conditions. For the treatment, several pharmacological agents exist, such as benzodiazepines, barbiturates, or dexmedetomidine. Nonetheless, as alcohol withdrawal syndromes can occur in every clinical setting, it is necessary to provide a guideline for clinicians confronted with this syndrome in varying clinical contexts.

AREAS COVERED

The authors provide a systematic review of the literature found in PubMed and Embase following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

EXPERT OPINION

For the treatment of alcohol withdrawal syndrome, medications targeting the GABA system are preferred. Benzodiazepines are regarded as the gold standard. However, as many adjunct therapeutic options exist, it is essential to find symptom-triggered approaches and treatment protocols for the variety of clinical contexts. Apart from that, it is necessary to compare protocols toward clinical variables rather than investigating medications that are in use for the treatment of alcohol withdrawal syndrome.

Management of Alcohol Withdrawal in the Emergency Department: Current Perspectives

Alcohol withdrawal syndrome (AWS) is a common, heterogenous, and life-threatening complication of alcohol use disorder (AUD). AUD is a leading cause of worldwide mortality, and many patients with AUD will develop AWS during their ED course. This review summarizes the epidemiology, pathology, and management of AWS and AUD in the emergency setting. The time course of AWS and its impact on ED treatment is emphasized. Once AWS is diagnosed, symptom-triggered benzodiazepine administration remains the most commonly provided treatment but may not be appropriate for patients with significant medical or psychiatric comorbidity or pending discharge. In these cases, ED clinicians may consider short courses of barbiturates or alternative regimens based on novel anticonvulsants. Specific treatment protocols are enumerated for clinical practice. Finally, emergency providers must not only manage acute patients' AWS but also lay the foundation for successful treatment of AUD. An approach to the disposition of the patient with AUD is presented. The authors examine shortcomings in the extant literature and suggest opportunities for further study.

Repurposing Potential of Ketamine: Opportunities and Challenges

Ketamine is a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor which also interacts with various other receptors that account for its myriad actions. Originally approved as a general anesthetic, it is being explored to be repurposed for numerous other indications such as depressive disorders, suicidal ideation, substance-use disorders, anxiety disorders, chronic pain, refractory status epilepticus, and bronchial asthma exacerbations. Numerous trials are ongoing for the same. The nasal spray of esketamine, a more potent S (+) enantiomer of ketamine, has been approved by the United States Food and Drug Administration (USFDA) for treatment-resistant depression along with the oral antidepressants. However, there are concerns about its safety on long term use, given its psychedelic effects and potential abuse. In this review, we discuss repurposing ketamine for potential therapeutic use and about the safety concerns related to ketamine and esketamine.

Adjunct Ketamine Use in the Management of Severe Ethanol Withdrawal

OBJECTIVES

Ketamine offers a plausible mechanism with favorable kinetics in treatment of severe ethanol withdrawal. The purpose of this study is to determine if a treatment guideline using an adjunctive ketamine infusion improves outcomes in patients suffering from severe ethanol withdrawal.

DESIGN

Retrospective observational cohort study.

SETTING

Academic tertiary care hospital.

PATIENTS

Patients admitted to the ICU and diagnosed with delirium tremens by Diagnostic and Statistical Manual of Mental Disorders V criteria.

INTERVENTIONS

Pre and post guideline, all patients were treated in a symptom-triggered fashion with benzodiazepines and/or phenobarbital. Postguideline, standard symptom-triggered dosing continued as preguideline, plus, the patient was initiated on an IV ketamine infusion at 0.15-0.3 mg/kg/hr continuously until delirium resolved. Based upon withdrawal severity and degree of agitation, a ketamine bolus (0.3 mg/kg) was provided prior to continuous infusion in some patients.

MEASUREMENTS AND MAIN RESULTS

A total of 63 patients were included (29 preguideline; 34 postguideline). Patients treated with ketamine were less likely to be intubated (odds ratio, 0.14; p < 0.01; 95% CI, 0.04-0.49) and had a decreased ICU stay by 2.83 days (95% CI, -5.58 to -0.089; p = 0.043). For ICU days outcome, correlation coefficients were significant for alcohol level and total benzodiazepine dosing. For hospital days outcome, correlation coefficients were significant for patient age, aspartate aminotransferase, and alanine aminotransferase level. Regression revealed the use of ketamine was associated with a nonsignificant decrease in hospital stay by 3.66 days (95% CI, -8.40 to 1.08; p = 0.13).

CONCLUSIONS

Mechanistically, adjunctive therapy with ketamine may attenuate the demonstrated neuroexcitatory contribution of N-methyl-D-aspartate receptor stimulation in severe ethanol withdrawal, reduce the need for excessive gamma-aminobutyric acid agonist mediated-sedation, and limit associated morbidity. A ketamine infusion in patients with delirium tremens was associated with reduced gamma-aminobutyric acid agonist requirements, shorter ICU length of stay, lower likelihood of intubation, and a trend toward a shorter hospitalization.

Ketamine applications beyond anesthesia - A literature review

Ketamine's clinical use began in the 1970s. Physicians benefited from its safety and ability to induce short-term anesthesia and analgesia. The psychodysleptic effects caused by the drug called its further clinical use into question. Despite these unpleasant effects, ketamine is still applied in veterinary medicine, field medicine, and specialist anesthesia. Recent intensive research brought into light new possible applications of this drug. It began to be used in acute, chronic and cancer pain management. Most interesting reports come from research on the antidepressive and antisuicidal properties of ketamine giving hope for the creation of an effective treatment for major depressive disorder. Other reports highlight the possible use of ketamine in treating addiction, asthma and preventing cancer growth. Besides clinical use, the drug is also applied to in animal model of schizophrenia. It seems that nowadays, with numerous possible applications, the use of ketamine has returned; to its former glory. Nevertheless, the drug must be used with caution because still the mechanisms by which it executes its functions and long-term effects of its use are not fully known. This review aims to discuss the well-known and new promising applications of ketamine.

Delirium Tremens: Assessment and Management

Delirium Tremens (DT) falls in the most severe spectrum of alcohol withdrawal, which could potentially result in death, unless managed promptly and adequately. The prevalence of DT in general population is <1% and nearly 2% in patients with alcohol dependence. DT presents with a combination of severe alcohol withdrawal symptoms and symptoms of delirium with agitation and sometimes hallucination. Clinical and laboratory parameters which predict DT have been discussed. Assessment of DT includes assessment of severity of alcohol withdrawal, evaluation of delirium, and screening for underlying medical co-morbidities. Liver disease as a co-morbidity is very common in patients with DT and that could complicate the clinical presentation, determine the treatment choice, and influence the outcome. Benzodiazepines are the mainstay of treatment for DT. Diazepam and lorazepam are preferred benzodiazepine, depending upon the treatment regime and clinical context. In benzodiazepine refractory cases, Phenobarbital, propofol, and dexmedetomidine could be used.

Predictors of resistant alcohol withdrawal (RAW): A retrospective case-control study

BACKGROUND

Benzodiazepine-resistant alcohol withdrawal (RAW), defined by a requirement of ≥ 40 mg of diazepam in 1 h, represents a severe form of withdrawal without predictive parameters. This study was designed to identify risk factors associated with RAW versus withdrawal without benzodiazepine resistance (nRAW).

METHODS

A retrospective cohort of adults with severe alcohol withdrawal were screened. Demographic and clinical variables, collected through chart review, underwent logistic regression to select the subset that predicst RAW.

RESULTS

736 patients (515 nRAW, 221 RAW) were analyzed. RAW patients were younger (P < 0.001), male (P = 0.008) Caucasians (P = 0.037) with histories of psychiatric illness (P < 0.001), higher serum ethanol concentrations (P < 0.007), and abnormal liver enzymes (P = 0.01). RAW patients had significantly lower platelets (P < 0.001), chloride (P = 0.02), and potassium (P = 0.01) levels; severity of illness (SAPSII) (P < 0.001) and comorbidity scores (P < 0.001). Caucasian race and male gender were found to be 3.6 and 2.6 times more likely to be RAW. For every 1-unit increase in comorbidity and severity of illness scores, patients were 22% [OR(95% CI) 0.78 (0.66-0.90)] and 4% [0.96 (0.93-0.98)] less likely to be RAW. Patients with a psychiatric history or thrombocytopenia were 2 times more likely [2.02 (1.24-3.30); 2.13 (1.31-3.50), respectively] to be RAW.

CONCLUSION

These data demonstrate the predictive ability of a history of psychiatric illness, thrombocytopenia, gender, race, baseline severity of illness and comorbidity scores for developing RAW. Considering these characteristics in early withdrawal management may prevent progression to RAW outcomes.

Adjunctive Use of Ketamine for Benzodiazepine-Resistant Severe Alcohol Withdrawal: a Retrospective Evaluation

INTRODUCTION

Benzodiazepine (BZD)-resistant alcohol withdrawal remains a challenge for most institutions due to limited evidence with available agents. One published study currently exists utilizing the N-methyl-D-aspartate antagonist, ketamine, for alcohol withdrawal.

OBJECTIVE

The purpose of our study was to evaluate the effect of adjunctive ketamine continuous infusion on symptom control and lorazepam infusion requirements for BZD-resistant alcohol withdrawal patients in the intensive care unit.

METHODS

A retrospective review was conducted of patients receiving ketamine adjunctively with a lorazepam infusion for severe alcohol withdrawal between August 2012 and August 2014. Outcomes included time to symptom control, lorazepam infusion requirements, ketamine initial and maximum daily infusion rates, and adverse effects of ketamine.

RESULTS

Thirty patients were included in the analysis. Mean time to initiation of ketamine after the initiation of a lorazepam infusion was 41.4 h. All patients achieved initial symptom control within 1 h of ketamine initiation. Median initial ketamine infusion rate was 0.75 mg/kg/h and the average maximum daily rate was 1.6 mg/kg/h. Significant decreases in lorazepam infusion rates from baseline were observed at 24 h (- 4 mg/h; p = 0.01) after ketamine initiation. No patients experienced documented CNS adverse effects. Two patients experienced hypertension and no patients experienced tachycardia related to ketamine.

CONCLUSION

Adjunctive ketamine could provide symptom control for BZD-refractory patients and may potentially reduce lorazepam infusion requirements. Future studies to determine optimal dosing, timing of initiation, and place in therapy for BZD-resistant alcohol withdrawal are needed. The mechanism of action via the NMDA receptor with ketamine may provide benefit for BZD-resistant alcohol withdrawal.

The Assessment and Management Practices of Acute Alcohol Withdrawal: Results of a Nationwide Survey of Critical Care Pharmacists

Background: Alcohol withdrawal occurs commonly but diagnosis and therapies have not been described. Objective: To characterize practices regarding the assessment and treatment of acute severe alcohol withdrawal and describe perceived barriers to therapies. Methods: A random sample of 500 US-based critical care pharmacists received the pretested, electronically distributed questionnaire. Results: 94 (20%) of 471 eligible recipients responded with diverse representation. Manifestations of alcohol withdrawal that were commonly rated as severe were seizures (91.3%), not oriented to person/place/date (84.1%), delusions (73.8%), diastolic blood pressure >110 mmHg (51.7%), inconsolable agitation (50.7%), and tachycardia (50.7%). Scoring tools were considered highly effective for assessing severity by 43 respondents (45.8%). Management protocols existed in 86 (90.5%) institutions. Sixty-eight (72.3%) respondents indicated protocols were used often/routinely for initial management but only 23 (24.5%) for adjunctive therapies (p<0.0001). Agents employed for initial and adjunctive management were benzodiazepines (92.6% and 61.7%, respectively, p<0.0001), clonidine (29.8% and 34%, respectively), haloperidol (26.6% and 33%, respectively), and barbiturates (20.2% and 24.5%, respectively). Adjunctive agents were most commonly added to reduce dosages of benzodiazepines (antipsychotics, barbiturates, alpha-2 agonists), prevent respiratory depression (alpha-2 agonists), prevent or treat autonomic symptoms (alpha-2 agonists), and prevent or treat agitation/delusions (antipsychotics, barbiturates, alpha-2 agonists). Agents with common barriers to use were dexmedetomidine (bradycardia, hypotension, cost), propofol (hypotension, tracheal intubation required), and ketamine (lack of supportive data). Conclusion: Assessment and management strategies of acute severe alcohol withdrawal vary considerably. Benzodiazepines are the mainstay of treatment. Other agents are commonly used to prevent complications from benzodiazepines or treat agitation/delusions.

Efficacy of Ketamine in the Treatment of Substance Use Disorders: A Systematic Review

Background: Despite advances in behavioral and pharmacotherapy interventions, substance use disorders (SUDs) are frequently refractory to treatment. Glutamatergic dysregulation has received increasing attention as one common neuropathology across multiple substances of abuse. Ketamine is a potent N-methyl-D-aspartate (NMDA) glutamatergic receptor antagonist which has been found to be effective in the treatment of severe depression. Here we review the literature on the efficacy of ketamine in the treatment of SUDs. Methods: A systematic review of the PubMed, Scopus, and ClinicalTrials.gov databases was undertaken to identify completed and ongoing human studies of the effectiveness of ketamine in the treatment of SUDs between January 1997 and January 2018. Results and conclusion: Seven completed studies were identified. Two studies focused on alcohol use disorder, two focused on cocaine use disorder, and three focused on opioid use disorder. Both cocaine studies found improvements in craving, motivation, and decreased cocaine use rates, although studies were limited by small sample sizes, a homogeneous population and short follow-up. Studies of alcohol and opioid use disorders found improvement in abstinence rates in the ketamine group, with significant between-group effects noted for up to two years following a single infusion, although these were not placebo-controlled trials. These results suggest that ketamine may facilitate abstinence across multiple substances of abuse and warrants broader investigation in addiction treatment. We conclude with an overview of the six ongoing studies of ketamine in the treatment of alcohol, cocaine, cannabis, and opioid use disorders and discuss future directions in this emerging area of research.

Treatment of Severe Alcohol Withdrawal: A Focus on Adjunctive Agents

Objective:To review adjunctive treatment options for severe alcohol withdrawal. Data Sources: The search strategy included a search of Ovid MEDLINE using keywords alcohol withdrawal, severe alcohol withdrawal, AWS, delirium tremens, delirium, dexmedetomidine, propofol, anticonvulsants, clonidine, and phenobarbital and included articles dated from January 1990 to March 2017. Study Selection and Data Extraction: All English-language clinical trials and case reports assessing the efficacy of adjunctive agents in severe alcohol withdrawal were evaluated. Data Synthesis: Although first-line pharmacotherapy for alcohol withdrawal continues to be benzodiazepines, literature does not clearly define adjunctive treatment options for severe alcohol withdrawal. During severe alcohol withdrawal patients may become unable to tolerate or may become unresponsive to high-dose benzodiazepines. Large doses of benzodiazepines may also result in oversedation, respiratory insufficiency, and worsening delirium. Conclusions: Phenobarbital and dexmedetomidine are both viable adjunctive treatment options for severe alcohol withdrawal. Current evidence has shown these agents decrease the dose requirements of benzodiazepines with limited incidence of adverse reactions. Propofol may also be a viable option in mechanically ventilated patients, but its lack of clear safety and efficacy advantages over current treatment options may limit its use in practice. Clonidine, oral anticonvulsants, and ketamine require further controlled clinical trials to clearly define their role in the treatment of severe alcohol withdrawal.

The emergency medicine management of severe alcohol withdrawal

INTRODUCTION

Alcohol use is widespread, and withdrawal symptoms are common after decreased alcohol intake. Severe alcohol withdrawal may manifest with delirium tremens, and new therapies may assist in management of this life-threatening condition.

OBJECTIVE

To provide an evidence-based review of the emergency medicine management of alcohol withdrawal and delirium tremens.

DISCUSSION

The underlying pathophysiology of alcohol withdrawal syndrome (AWS) is central nervous system hyperexcitation. Stages of withdrawal include initial withdrawal symptoms, hallucinations, seizures, and delirium tremens. Management focuses on early diagnosis, resuscitation, and providing medications with gamma-aminobutyric acid (GABA) receptor activity. Benzodiazepines with symptom-triggered therapy have been the predominant medication class utilized and should remain the first treatment option with rapid escalation of dosing. Treatment resistant withdrawal warrants the use of phenobarbital or propofol, both demonstrating efficacy in management. Propofol can be used as an induction agent to decrease the effects of withdrawal. Dexmedetomidine does not address the underlying pathophysiology but may reduce the need for intubation. Ketamine requires further study. Overall, benzodiazepines remain the cornerstone of treatment. Outpatient management of patients with minimal symptoms is possible.

CONCLUSIONS

Alcohol withdrawal syndrome can result in significant morbidity and mortality. Physicians must rapidly diagnose these conditions while evaluating for other diseases. Benzodiazepines are the predominant medication class utilized, with adjunctive treatments including propofol or phenobarbital in patients with withdrawal resistant to benzodiazepines. Dexmedetomidine and ketamine require further study.

Acute Ethanol Inhibition of γ Oscillations Is Mediated by Akt and GSK3β

Hippocampal network oscillations at gamma band frequency (γ, 30-80 Hz) are closely associated with higher brain functions such as learning and memory. Acute ethanol exposure at intoxicating concentrations (≥50 mM) impairs cognitive function. This study aimed to determine the effects and the mechanisms of acute ethanol exposure on γ oscillations in an in vitro model. Ethanol (25-100 mM) suppressed kainate-induced γ oscillations in CA3 area of the rat hippocampal slices, in a concentration-dependent, reversible manner. The ethanol-induced suppression was reduced by the D1R antagonist SCH23390 or the PKA inhibitor H89, was prevented by the Akt inhibitor triciribine or the GSk3β inhibitor SB415286, was enhanced by the NMDA receptor antagonist D-AP5, but was not affected by the MAPK inhibitor U0126 or PI3K inhibitor wortmanin. Our results indicate that the intracellular kinases Akt and GSk3β play a critical role in the ethanol-induced suppression of γ oscillations and reveal new cellular pathways involved in the ethanol-induced cognitive impairment.

Unhealthy Alcohol Use

Unhealthy alcohol use is common and routine screening is essential to identify patients and initiate appropriate treatment. At-risk or hazardous drinking is best managed with brief interventions, which can be performed by any provider and are designed to enhance patients' motivations and promote behavioral change. Alcohol withdrawal can be managed, preferably with benzodiazepines, using a symptom-triggered approach. Twelve-step programs and provider-driven behavioral therapies have robust data supporting their effectiveness and patients with alcohol use disorder should be referred for these services. Research now support the use of several FDA-approved medications that aid in promoting abstinence and reducing heavy drinking.

Case Presentations from the Addiction Academy

In this article, a case-based format is used to address complex clinical issues in addiction medicine. The cases were developed from the authors' practice experience, and were presented at the American College of Medical Toxicology Addiction Academy in 2015. Section I: Drug and Alcohol Dependence and Pain explores cases of patients with co-occurring pain and substance use disorders. Section II: Legal and Policy Issues in Substance Use Disorders highlights difficult legal and policy questions in addiction medicine. Section III: Special Populations and Addictive Disorders delves into the complexity of addiction in special populations (pregnant, pediatric, and geriatric patients).

Treatment of Severe Alcohol Withdrawal

OBJECTIVE

Approximately 50% of patients with alcohol dependence experience alcohol withdrawal. Severe alcohol withdrawal is characterized by seizures and/or delirium tremens, often refractory to standard doses of benzodiazepines, and requires aggressive treatment. This review aims to summarize the literature pertaining to the pharmacotherapy of severe alcohol withdrawal.

DATA SOURCES

PubMed (January 1960 to October 2015) was searched using the search termsalcohol withdrawal, delirium tremens, intensive care, andrefractory Supplemental references were generated through review of identified literature citations.

STUDY SELECTION AND DATA EXTRACTION

Available English language articles assessing pharmacotherapy options for adult patients with severe alcohol withdrawal were included.

DATA SYNTHESIS

A PubMed search yielded 739 articles for evaluation, of which 27 were included. The number of randomized controlled trials was limited, so many of these are retrospective analyses and case reports. Benzodiazepines remain the treatment of choice, with diazepam having the most favorable pharmacokinetic profile. Protocolized escalation of benzodiazepines as an alternative to a symptom-triggered approach may decrease the need for mechanical ventilation and intensive care unit (ICU) length of stay. Propofol is appropriate for patients refractory to benzodiazepines; however, the roles of phenobarbital, dexmedetomidine, and ketamine remain unclear.

CONCLUSIONS

Severe alcohol withdrawal is not clearly defined, and limited data regarding management are available. Protocolized administration of benzodiazepines, in combination with phenobarbital, may reduce the need for mechanical ventilation and lead to shorter ICU stays. Propofol is a viable alternative for patients refractory to benzodiazepines; however, the role of other agents remains unclear. Randomized, prospective studies are needed to clearly define effective treatment strategies.

Alcohol Withdrawal Syndrome: Benzodiazepines and Beyond

Alcohol dependence is an increasing and pervasive problem. Alcohol withdrawal symptoms are a part of alcohol dependence syndrome and are commonly encountered in general hospital settings, in most of the departments. Alcohol withdrawal syndrome ranges from mild to severe. The severe complicated alcohol withdrawal may present with hallucinations, seizures or delirium tremens. Benzodiazepines have the largest and the best evidence base in the treatment of alcohol withdrawal, and are considered the gold standard. Others, such as anticonvulsants, barbiturates, adrenergic drugs, and GABA agonists have been tried and have evidence. Supportive care and use of vitamins is essential in the management. Symptom triggered regime is favoured over fixed tapering dose regime, although monitoring through scales is cumbersome. This article aims to review the evidence base for appropriate clinical management of the alcohol withdrawal syndrome. We searched Pubmed for articles published in English on 'Alcohol withdrawal syndrome' in humans during the last 10 years. A total of 1182 articles came up. Articles not relevant to clinical utility and management were excluded based on the titles and abstract available. Full text articles, meta-analyses, systematic reviews and randomized controlled trials were obtained from this list and were considered for review.

Management of benzodiazepine-resistant alcohol withdrawal across a healthcare system: Benzodiazepine dose-escalation with or without propofol

BACKGROUND

Severe cases of alcohol withdrawal syndrome (AWS) may not resolve despite escalating doses of benzodiazepines (BZDs). Benzodiazepine-resistant alcohol withdrawal (RAW) is a subset of severe alcohol withdrawal defined by the requirement of ≥40mg of diazepam administered within one hour. Use of adjunct agents, such as propofol, may be beneficial to minimize BZD adverse effects and improve symptom control. While limited evidence suggests propofol as an effective adjunct in AWS through improved sedation, evidence is currently lacking for the addition of only propofol to BZDs for management of RAW.

METHODS

Retrospective review of adult patients from January, 2009 to March, 2012 with RAW. Patients were categorized into BZD dose-escalation only or BZD plus propofol. The primary endpoint was time to resolution of AWS. Secondary endpoints included safety outcomes associated with medication use.

RESULTS

Of 1083 patients with severe AWS, 66 RAW patients (n=33 BZD only, n=33 BZD plus propofol) met inclusion. Median time to AWS resolution was 5.0 and 7.0 days for BZD only vs. BZD plus propofol (p=0.025). Duration of mechanical ventilation, ICU and hospital length of stay were significantly higher with propofol (p=0.017, <0.001 and <0.001, respectively). Ten patients required intervention for management of propofol-induced adverse reactions.

CONCLUSIONS

The addition of propofol for RAW treatment is associated with significant increases in clinical care. While randomized, prospective evaluations are necessary to determine the cause of this association, our data suggests use of adjunctive propofol therapy in RAW is associated with longer and more complicated hospital admissions.