Front-Loaded Versus Low-Intermittent Phenobarbital Dosing for Benzodiazepine-Resistant Severe Alcohol Withdrawal Syndrome

Evaluation of Clinical Outcomes Associated With Phenobarbital With Taper Compared to No Taper for the Management of Alcohol Withdrawal Syndrome

BACKGROUND

Phenobarbital (PHB) has been shown to be an effective treatment of alcohol withdrawal syndrome (AWS), with multiple dosing strategies used (e.g., single-dose and symptom-triggered). Studies have often used tapered doses, typically following a front-loaded dose, despite PHB's long half-life which should lead to an ability to auto-taper.

OBJECTIVE

The purpose of this study was to compare clinical outcomes associated with two PHB dosing strategies (taper [T], no taper [NT]) for AWS.

METHODS

This retrospective cohort study compared adult patients admitted to the ICU from October 2017 to May 2019 who received an initial loading dose of PHB for AWS. The use of PHB was at the discretion of the clinician per our institutional guidelines. Prior to November 2018, patients were prescribed a PHB taper, while after this period, the taper was no longer recommended. The primary outcome was the proportion of patients requiring rescue PHB or adjunctive medications for AWS. Secondary outcomes included number of adjunctive agents used, prevalence of severe manifestations of AWS, ICU and hospital lengths of stay, and incidence of potentially significant drug interactions.

RESULTS

A total of 172 patients were included (T: n = 81, NT: n = 91). Baseline characteristics were similar between groups, including history of severe AWS and cumulative benzodiazepine dose pre-PHB. There was no difference in the primary outcome between groups (T: 70.4% vs NT: 59.3%, P = 0.152). The median number of adjunctive agents per patient, severe manifestations, and ICU and hospital length of stay did not differ between groups. Twenty-five patients (14.5%) had potentially significant drug interactions.

CONCLUSION AND RELEVANCE

The use of a PHB loading dose without a taper may be comparable to a taper strategy on clinical outcomes. Prospective studies are needed to further delineate the optimal dose of PHB for AWS.

Antibiotic prophylaxis reduced broad-spectrum antibiotics and length of stay in ICU patients with alcohol withdrawal induced refractory delirium tremens

Background

Pneumonia is a well-known complication in patients with severe alcohol withdrawal syndrome (SAWS). Antibiotic prophylaxis in ICU treated SAWS patients may be beneficial but data is lacking. The aims of this study were to investigate the effect of introduction of trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis, on use of broad-spectrum antibiotics and ICU length of stay (LOS) in SAWS patients with refractory delirium tremens (rDT).

Methods

Retrospective observational cohort study comparing before (control group) and after the introduction of TMP-SMX prophylaxis in patients admitted to a single center ICU because of alcohol withdrawal induced rDT.

Results

A total of 108 patients were included, 53 patients in the control group and 55 patients in the TMP-SMX group. Baseline characteristics did not differ between the groups (89% male, median age 52 years). The use of broad-spectrum antibiotics was significantly lower in the TMP-SMX group than in the control group (11 vs 70%, p < 0.001). The only variable associated with decreased use of broad-spectrum antibiotics in multiple logistic regression analysis was receiving TMP-SMX (0.06, 95% CI 0.02, 0.19, p-value: <0.001). Median LOS was shorter in the TMP-SMX group than in the control group (61 vs 72 h, p = 0.004). In multiple linear regression analysis receiving TMP-SMX SMX was associated with shorter LOS (-22.7, 95% CI: -41.3, -4.1, p-value: 0.02) and having one or more comorbidities with longer LOS (37.4, 95% CI: 10.4, 64.5, p-value: <0.01).

Conclusion

Prophylaxis with TMP-SMX in ICU-treated rDT patients was associated with reduced use of broad-spectrum antibiotics and reduced ICU LOS.

Effect of Phenobarbital-Based Alcohol Withdrawal Protocol on Provider Practice and Patient Outcomes-A Quality Improvement Study

Introduction: Alcohol is the most common substance use disorder in the United States. Despite this prevalence, there remains significant heterogeneity in medical management of alcohol withdrawal syndrome (AWS). While the 2020 American Society of Addition Medicine continues to recommend the use of benzodiazepines as first-line therapy for AWS, there is increasing use of phenobarbital in patients at high risk of severe AWS. Despite phenobarbital's favorable pharmacologic profile, historically, clinical utilization on general medicine services has been low and often restricted. In this project, we have examined practice patterns and associated clinical outcomes in adult patients experiencing AWS on the general medicine service pre and post implementation of a phenobarbital-based protocol for the treatment of severe AWS at our institution. Methods: This quality improvement study evaluated changes in management of AWS on general medicine units associated with implementation of a phenobarbital-based protocol and order set in the electronic medical record (EMR). Our primary outcome measures were receipt of a phenobarbital loading dose, concomitant benzodiazepine administration, and total benzodiazepine dose. Safety outcomes were also explored to assess clinical impacts of this protocol implementation. The project was determined "not research" by our Institutional Review Board. Results: Phenobarbital-protocol implementation was associated with increased frequency of receiving a phenobarbital loading dose (49.5% vs 9.4%; P < .001), decreased use of concomitant benzodiazepine/phenobarbital (4.3% vs 28.9%; P < .001), and decreased total benzodiazepine dose (7.8 vs 15.5 mg; P < .001). Regarding safety, there was no significant pre/post difference in the rate of ICU transfer, but among those transferred there was a trend toward decreased mechanical ventilation rate (100% vs 28.6%; P = .051), and a significantly reduced ICU length of stay (median 11 vs 3 days; P = .04). There were no pre/post differences in seizures, delirium or use of adjunct medications. Conclusions: This quality improvement study demonstrates a marked change in provider prescribing practices for treating AWS after implementation of an institutional phenobarbital-based protocol. We observed no difference in overall clinical outcomes after protocol implementation, although a larger follow-up study is needed to confirm this and to further explore the shorter ICU length of stay for patients with AWS postimplementation.

Phenobarbital Dosing for the Treatment of Alcohol Withdrawal Syndrome: A Review of the Literature

Objective: To determine the most appropriate phenobarbital dosing regimen by evaluating the safety and efficacy of the drug when specifically used in alcohol withdrawal syndrome (AWS). Data sources: A comprehensive literary search was conducted using PubMed and bibliographic mining in October 2023. Study selection and data extraction: An established monotherapy phenobarbital regimen needed to be established within the article to be included in analysis. Location of implementation was not a deterrent to evaluation, nor was the route of phenobarbital administration. Data synthesis: Six publications were evaluated in this review, and two main phenobarbital dosing regimens emerged. While fix-based dosing strategies and weight-based dosing strategies resulted, the dosing within the regimens resulted in the same or relatively similar doses employed, respectively. Each of the studies had a statistically significant decrease in their primary outcome being studied, and the use of phenobarbital as monotherapy was proven to improve AWS symptoms, significantly decrease intensive care unit and hospital length of stay, decrease the use of adjunctive medications, decrease the use of a ventilator, and prevent seizures. Conclusions: Despite benzodiazepines having been the clinical first-line therapy for AWS, research shows that the pharmacokinetic stability and clinical benefits of phenobarbital are in support creation of phenobarbital protocols, as monotherapy, in hospitals or institutions for patients with AWS.

Evaluation of phenobarbital dosing strategies for hospitalized patients with alcohol withdrawal syndrome

OBJECTIVE

Alcohol remains the fourth‑leading preventable cause of death in the U.S. The objective of this study was to compare the incidence of phenobarbital (PHB)-resistant withdrawal and determine risk factors for PHB-resistant alcohol withdrawal syndrome (AWS).

METHODS

This retrospective cohort study included adults admitted to an academic center with AWS who received PHB as part of an institution-specific treatment protocol. The primary outcome was incidence of AWS resistant to initial protocolized PHB load across two cohorts (standard-dose, 10 mg/kg vs. low-dose, 6 mg/kg).

RESULTS

Among 176 included patients, there was no difference in the incidence of PHB-resistant AWS based on initial PHB load [low-dose load, 21 (18.3%) vs. standard-dose load, 12 (19.7%), p = 0.82]. There were also no differences in observed PHB-related ADEs between the groups. Total benzodiazepine dose received (mg) in the 24 h prior to initial PHB load was the only risk factor significantly associated with AWS resistant to initial protocolized PHB load [adjusted OR 1.79 (95% CI 1.24, 2.60)]. PHB-resistant withdrawal occurred in 33 (18.8%) patients with a median cumulative PHB dose of approximately 20 mg/kg during hospitalization.

CONCLUSION(S)

There were no differences in the incidence of PHB-resistant AWS or PHB-related ADEs based on initial PHB loading dose.

Phenobarbital and Alcohol Withdrawal Syndrome: A Systematic Review and Meta-Analysis

Alcohol withdrawal syndrome (AWS) is a complication frequently encountered among patients who are chronic alcohol abusers. It is considered to have a significant impact on the United States healthcare system. It not only has a toll on the healthcare spending but also contributes to significant morbidity and mortality. Benzodiazepines are considered first line in the treatment of AWS. Since patients with alcohol use disorder have downregulated gamma aminobutyric acid (GABA) receptors, this often leads to benzodiazepine resistance. Phenobarbital is also used in the management of alcohol withdrawal syndrome. Here we present a systematic review and meta-analysis of the efficacy and safety of the drug. We conducted an electronic database search for relevant studies published between the inception of the project and November 20, 2022, in three databases, including Medline/PubMed, Embase, and Cochrane Library. Our study included all original studies with prime focus on the baseline characteristics of patients admitted to the intensive care unit (ICU) for alcohol withdrawal syndrome and management/monitoring protocol implemented for its treatment. The primary outcomes that were the focus of our study consisted of changes in the length of hospital stay, length of ICU stay, and changes in scoring systems (for alcohol withdrawal assessment and monitoring) following the implementation of phenobarbital. The secondary outcomes included complications such as intubation and mortality. Based on our analysis, the mean difference in hospital stay was statistically significant at -2.6 (95% CI, -4.48, -0.72, P=0.007) for phenobarbital compared to the benzodiazepine group. We were unable to comment on the heterogeneity in our meta-analysis due to the standard deviation not being reported in one study. There was no statistically significant difference regarding the length of stay in the intensive care unit compared to the control/comparative arm, with a mean difference of -1.17 (95% CI, -1.17, 0.09, P=0.07), with considerable heterogeneity (I2=77%, P=0.002). Our meta-analysis also investigated the risk of intubation between the phenobarbital and the control/comparative group. There was statistically significant difference in the incidence of intubation, relative risk (RR) 0.52 (95% CI, 0.25, 1.08, P=0.08), with considerable heterogeneity (I2=80%, P=0.0001). Our study concludes that phenobarbital is an effective tool in the management of AWS in an ICU setting. However, various studies have reported contradictory results, and vital information appears to be lacking. Moreover, there is a lack of uniformity in terms of phenobarbital dosing. Drug administration should be adapted according to the severity of the symptoms. Further studies need to be conducted discussing the safety profile and adverse effects of the drug when it comes to the management of alcohol withdrawal syndrome.