Alcohol withdrawal syndrome: mechanisms, manifestations, and management

The Safety and Utility of Phenobarbital Use for the Treatment of Severe Alcohol Withdrawal Syndrome in the Medical Intensive Care Unit

BACKGROUND

Alcohol withdrawal syndrome (AWS) is a common reason for admission to a medical intensive care unit (MICU) and requires significant hospital resource utilization. Benzodiazepines are first-line therapy for AWS in many intensive care units. We propose the use of symptom-triggered phenobarbital for the treatment of AWS as a safe alternative to benzodiazepines.

METHODS

This was a retrospective observational study of a 4-year period, 2011 to 2015, of all patients with AWS admitted to the MICU of 1 tertiary care hospital and treated with phenobarbital. A symptom-triggered protocol was used. Resolution of AWS was assessed with the Richmond Agitation Sedation Scale to goal score of 0 to -1. The Charlson Comorbidity Index was used as an index of patient illness severity. Complications associated with phenobarbital use and/or the AWS admission were analyzed.

RESULTS

Data of 86 AWS patient encounters were analyzed. The mean Clinical Institute Withdrawal Assessment for Alcohol-Revised score of patients admitted to the MICU with AWS was 19 ± 9. The mean phenobarbital dose administered during the MICU stay was 1977.5 ± 1531.5 mg. There were a total of 17 (20%) intubations. The most frequent cause of mechanical ventilation in patients with AWS was loss of airway clearance, followed by hemodynamic instability secondary to upper gastrointestinal bleeding and the corresponding need for endoscopy.

CONCLUSIONS

Sole use of phenobarbital use for control of AWS may be a safe alternative to benzodiazepines. Further study is needed to correlate phenobarbital serum levels with clinical control of AWS.

Individual differences in response to alcohol exposure in zebrafish (Danio rerio)

Personality traits are related to many aspects of one's life, including risk taking, sociability, and behavioral changes caused by psychoactive substances. This study aimed to investigate individual differences and behavioral changes due to alcohol exposure in zebrafish (Danio rerio). To that end, adult animals were separated into two behavioral profiles: bold and shy, according to their risk taking behavior in an emergence test. Bold and shy fish were allowed to explore a 5-chamber tank and were tested for exploration and sociability (shoaling behavior) following alcohol exposure. The acute drug exposure treatments were 0.0%, 0.1% and 0.5% (v/v%) alcohol. The behavioral parameters evaluated were average and maximum swimming speed, total distance traveled, total time spent immobile, and time spent near a shoal or exploring the tank. For the groups that received no alcohol (0.0% alcohol), shy individuals spent more time near the shoal than bold fish. However, 0.5% alcohol increased bold fish responsiveness to the shoal, while both 0.1% and 0.5% alcohol diminished shoaling in shy fish. Our results show that the behavioral profiles of zebrafish are affected differently by alcohol, with shy animals seemingly more sensitive to behavioral change due to drug exposure. Moreover, we confirm zebrafish as a model for alcohol induced functional (exploration and social behavior) changes that could be useful in high throughput drug screens.

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.

DNA damage and oxidative stress induced by seizures are decreased by anticonvulsant and neuroprotective effects of lobeline, a candidate to treat alcoholism

The alkaloid lobeline (Lob) has been studied due to its potential use in treatment of drug abuse. This study evaluates the possible anticonvulsant and neuroprotective activities of Lob to obtain new information on its properties that could confirm it as a candidate in the treatment of alcohol addiction. The anticonvulsant effect of Lob was evaluated using a pilocarpine-induced seizure model. In addition, possible neuroprotective effects were investigated measuring DNA damage using the comet assay, assessing free radical levels by dichlorofluorescein diacetate (DCF) oxidation, and measuring the antioxidant potential using the α, α-diphenyl-β-picrylhydrazyl (DPPH) scavenging assay, besides measuring superoxide dismutase (SOD) and catalase (CAT) enzyme activities in brain tissues. Lobeline increased the latency to the first seizure and decreased the percentage of seizures in a similar way as diazepam, used as control. DNA damage induced by Pil and hydrogen peroxide were decreased in hippocampus and cerebral cortex from mice treated with Lob. The levels of free radicals and CAT activity increased in cortex and hippocampus, respectively, in mice treated with Pil. Lobeline decreased CAT in hippocampus, leading to similar values as in the saline negative control. In conclusion, Lob has anticonvulsant and neuroprotective actions that may be mediated by antioxidant-like mechanisms, indicating its potential as candidate drug in alcoholism therapy.

Short-Term Alcohol Abstinence Improves Antibacterial Defenses of Chronic Alcohol-Consuming Mice against Gut Bacteria-Associated Sepsis Caused by Enterococcus faecalis Oral Infection

The effects of short-term alcohol abstinence on host antibacterial resistance against Enterococcus faecalis oral infection was investigated in chronic alcohol-consuming mice [mice with 0.1 g/day of 20% ethanol consumption for 12 or 16 weeks (CAC-mice)]. These mice were highly susceptible to the infection; however, after 7 days of alcohol abstinence (aaCAC-mice), their antibacterial resistances were completely restored to the normal mouse level. Normal mice inoculated with CAC-mouse hepatic macrophages were shown to be susceptible to the infection, whereas the same macrophage preparation from aaCAC-mice did not impair the antibacterial resistance of normal mice. aaCAC-mouse liver macrophages protected nonobese diabetic-severe combined immunodeficiency IL-2Rγ^null mice exposed to E. faecalis, whereas those from CAC-mice did not. Monocyte-derived (MD) M2b macrophages were predominantly isolated from CAC-mouse livers, but these cells were not significantly isolated from aaCAC-mouse livers. Hepatic MD macrophages from aaCAC-mice switched to M1 macrophages in response to bacterial antigen, whereas the same macrophage preparation from CAC-mice did not. M1 Kupffer cells, M2a Kupffer cells, and MD M2b macrophages were shown to be not bactericidal, whereas E. faecalis was killed effectively by M1 macrophages derived from aaCAC-mouse hepatic MD macrophages. These results indicate that MD M2b macrophages predominantly distributed in the liver are responsible for the impaired resistance of CAC-mice to E. faecalis oral infection, and aaCAC-mice without MD M2b macrophages in the livers are resistant to the infection.

Preserved Affective Sharing But Impaired Decoding of Contextual Complex Emotions in Alcohol Dependence

BACKGROUND

Prior research has repeatedly shown that alcohol dependence is associated with a large range of impairments in psychological processes, which could lead to interpersonal deficits. Specifically, it has been suggested that these interpersonal difficulties are underpinned by reduced recognition and sharing of others' emotional states. However, this pattern of deficits remains to be clarified. This study thus aimed to investigate whether alcohol dependence is associated with impaired abilities in decoding contextual complex emotions and with altered sharing of others' emotions.

METHODS

Forty-one alcohol-dependent individuals (ADI) and 37 matched healthy individuals completed the Multifaceted Empathy Test, in which they were instructed to identify complex emotional states expressed by individuals in contextual scenes and to state to what extent they shared them.

RESULTS

Compared to healthy individuals, ADI were impaired in identifying negative (Cohen's d = 0.75) and positive (Cohen's d = 0.46) emotional states but, conversely, presented preserved abilities in sharing others' emotional states.

CONCLUSIONS

This study shows that alcohol dependence is characterized by an impaired ability to decode complex emotional states (both positive and negative), despite the presence of complementary contextual cues, but by preserved emotion-sharing. Therefore, these results extend earlier data describing an impaired ability to decode noncontextualized emotions toward contextualized and ecologically valid emotional states. They also indicate that some essential emotional competences such as emotion-sharing are preserved in alcohol dependence, thereby offering potential therapeutic levers.

Alcohol withdrawal syndrome: mechanisms, manifestations, and management

The alcohol withdrawal syndrome is a well‐known condition occurring after intentional or unintentional abrupt cessation of heavy/constant drinking in patients suffering from alcohol use disorders (AUDs). AUDs are common in neurological departments with patients admitted for coma, epileptic seizures, dementia, polyneuropathy, and gait disturbances. Nonetheless, diagnosis and treatment are often delayed until dramatic symptoms occur. The purpose of this review is to increase the awareness of the early clinical manifestations of AWS and the appropriate identification and management of this important condition in a neurological setting.